Neoprene Selguide
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Technical Information A Guide to Grades, Compounding and Processing of Neoprene Rubber Inherent Properties of Neoprene Neoprene, the world’s first fully commercial synthetic elastomer, was introduced by DuPont in 1931. Since then it has established an enviable reputation for reliable service in many demanding applications. Based upon polychloroprene, alone or modified with sulphur and/or 2,3 dichloro 1,3-butadiene, Neoprene is a true multipurpose elastomer thanks to its balance of inher- ent properties, which include: • Outstanding physical toughness • Wider short- and long-term operating temperature range than general-purpose hydrocarbon elastomers • Resistance to hydrocarbon oils and heat (ASTM D2000/SAE J200 categories BC/BE) • Resistance to ozone, sun and weather • Better flame retardant/self extinguishing characteris- tics than exclusively hydrocarbon-based elastomers As with all elastomers, properties inherent in the base polymer can be enhanced or degraded by the com- pounding adopted. This concise guide will assist in the development of compounds with optimum service life which will process smoothly and economically. More detailed information on the available grades of Neoprene, processing and compounding for specific end-uses and specifications is available in a wide range of literature. Handling Precautions DuPont Dow Elastomers is unaware of any unusual health hazards associated with any Neoprene solid polymer. For all the solid polymers, routine industrial hygiene practices are recommended during handling and processing to avoid such conditions as dust buildup or static charges. For detailed information, read “Guide for Safety in Handling and FDA Status of Neoprene Solid Polymers,” and observe the precautions noted therein. Review current Material Safety Data Sheet (MSDS) for polymers and ingredients prior to first use and upon revisions. Before proceeding with any compounding work, consult and follow label directions and handling precautions from suppliers of all ingredients. Specify dust-free dispersions of all potentially hazard- ous ingredients. Ensure that local environmental and workplace handling requirements are met. Refer also to comments on specific compounding ingredients in the safe handling guide. Selection of Neoprene Type and Grade The various grades of Neoprene fall within three types, e.g., G, W and T. Within each type lies a series of grades that differ primarily in resistance to crystalli- zation and Mooney viscosity. Selection of type and grade is usually based upon a combination of four factors: Product performance Defined by the most important physical properties for optimum service life, e.g., tear and flex resis- tance (belts), compression set and stress relaxation resistance (seals, bearing pads), high and low temperature resistance (CVJ boots). Crystallization resistance As dictated by product operating temperatures and/ or processing needs. Mooney viscosity Suitable for the intended processing operations with the necessary form of compound. All DuPont Dow Elastomers grades of Neoprene have a viscosity measured using the ten pass method (N200.5700) and are measured ML 1+4 at 100°C. Building tack Ease of lamination in processing, where necessary. Basic characteristics of the three types are summa- rized in Table 1, with details following. Additional information may be found in individual product bulletins. Rev. 3, Jan. 2004
description
neoprene
Transcript of Neoprene Selguide
Technical Information○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○
A Guide to Grades, Compounding andProcessing of Neoprene Rubber
Inherent Properties of NeopreneNeoprene, the world’s first fully commercial syntheticelastomer, was introduced by DuPont in 1931. Sincethen it has established an enviable reputation forreliable service in many demanding applications. Basedupon polychloroprene, alone or modified with sulphurand/or 2,3 dichloro 1,3-butadiene, Neoprene is a truemultipurpose elastomer thanks to its balance of inher-ent properties, which include:• Outstanding physical toughness• Wider short- and long-term operating temperature
range than general-purpose hydrocarbon elastomers• Resistance to hydrocarbon oils and heat (ASTM
D2000/SAE J200 categories BC/BE)• Resistance to ozone, sun and weather• Better flame retardant/self extinguishing characteris-
tics than exclusively hydrocarbon-based elastomers
As with all elastomers, properties inherent in the basepolymer can be enhanced or degraded by the com-pounding adopted. This concise guide will assist in thedevelopment of compounds with optimum servicelife which will process smoothly and economically.More detailed information on the available grades ofNeoprene, processing and compounding for specificend-uses and specifications is available in a wide rangeof literature.
Handling PrecautionsDuPont Dow Elastomers is unaware of any unusualhealth hazards associated with any Neoprene solidpolymer. For all the solid polymers, routine industrialhygiene practices are recommended during handlingand processing to avoid such conditions as dust buildupor static charges. For detailed information, read “Guidefor Safety in Handling and FDA Status of NeopreneSolid Polymers,” and observe the precautions notedtherein.
Review current Material Safety Data Sheet (MSDS) forpolymers and ingredients prior to first use and uponrevisions.
Before proceeding with any compounding work,consult and follow label directions and handlingprecautions from suppliers of all ingredients.Specify dust-free dispersions of all potentially hazard-ous ingredients. Ensure that local environmental andworkplace handling requirements are met. Refer alsoto comments on specific compounding ingredients inthe safe handling guide.
Selection of Neoprene
Type and GradeThe various grades of Neoprene fall within threetypes, e.g., G, W and T. Within each type lies a seriesof grades that differ primarily in resistance to crystalli-zation and Mooney viscosity. Selection of type andgrade is usually based upon a combination of fourfactors:
Product performanceDefined by the most important physical propertiesfor optimum service life, e.g., tear and flex resis-tance (belts), compression set and stress relaxationresistance (seals, bearing pads), high and lowtemperature resistance (CVJ boots).Crystallization resistanceAs dictated by product operating temperatures and/or processing needs.Mooney viscositySuitable for the intended processing operations withthe necessary form of compound.All DuPont Dow Elastomers grades of Neoprenehave a viscosity measured using the ten passmethod (N200.5700) and are measured ML 1+4at 100°C.Building tackEase of lamination in processing, where necessary.
Basic characteristics of the three types are summa-rized in Table 1, with details following. Additionalinformation may be found in individual productbulletins.
Rev. 3, Jan. 2004
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Types of Neoprene
G-TypesCharacteristics that differentiate G-types derive fromtheir manufacture by the copolymerization of chloro-prene with sulphur, stabilized or modified with thiuramdisulfide. They have wider molecular weight distribu-tions than W- or T-types.
As compared with W-types, Neoprene G-grades:• Can be mechanically or chemically peptized to a
lower viscosity, hence can provide workable morehighly loaded stocks with minimum plasticizerlevels. Neoprene GW is essentially non-peptizable,which is the one notable exception.
• Are more tacky and less nervy, with the exceptionof gel-containing polymers. These properties lendthemselves to extrusion, frictioning, calendering andbuilding operations, as in hose and belt manufacture,and minimize knitting and backgrinding problems inmolding
• Have more limited raw polymer storage stability• Fully compounded, are more susceptible to total heat
history in processing and storage time (i.e., are moreprone to viscosity increase and reduction of scorchtime)
• Do not normally require organic accelerators.• Have highest tear strength, especially GRT and GW• Impart highest flex fatigue resistance, higher
elongation and resilience and a “snappier” feel tovulcanizates
Characteristics of Individual Grades
Medium crystallization speedNeoprene GNA-M1A moderate viscosity and crystallization resistantpolymer, thiuram disulphide stabilized and containing astaining secondary amine for improved polymerstability.
Slow crystallizingNeoprene GWAn optimized sulphur-modified polychloroprene withimproved storage and mill breakdown resistancesimilar to W-types but without the need for organicaccelerators. Tear strength, resilience and flex crackresistance are those of G-types. Heat resistanceapproaches thiourea cured W-grades. Compressionset resistance lies between that of traditional G and Wvariants.
Neoprene GRTA sulphur copolymer with good crystallization resis-tance. Has the best green tack of any Neoprene andis used extensively for frictioning, or where goodbuilding tack is required.
W-TypesAs compared with Neoprene G-types, W-grades:• Are more stable in the raw state• Mix faster but cannot be mechanically or chemically
peptized• Require organic accelerators. By selection of type
and level, they offer greater latitude in processingsafety and cure rate
• Are less prone to mill sticking and collapse onextrusion
• Offer superior vulcanizate heat and compression setresistance
• Accept higher levels of filler for a given level ofcompression set or tensile strength, hence can yieldmore economical compounds
• Can yield non-staining, non-tarnishing vulcanizates• Show improved color stability
Table 1Characteristics of Neoprene
Types G W T
Raw Polymer Limited storage stability Excellent storage stability Excellent storage stability
Polymer and compounds Non-peptizable Least nerve, non-peptizablepeptizable to varying degree Need acceleration
Fast curing but safe processing Best extrusion, calendering performance
Accelerators usually not necesary Need acceleration
Highest tack
Vulcanizates Best tear strength Best compression set resistance Properties similar to W-types
Best flex Best heat aging
Best resilience
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Characteristics of Individual Grades
Fast crystallizingNeoprene WA stabilized, rapid crystallizing chloroprene polymerwith good raw stability. Accelerated with ethylenethiourea (ETU), provides excellent heat and compres-sion set resistance.
Neoprene WM-1Lower viscosity Neoprene W for improved processingin highly loaded compounds and lower processingtemperatures.
Neoprene WHVHigh viscosity Neoprene W for low cost, highlyextended compounds or to raise the viscosity andgreen strength of lightly loaded or highly plasticizedcompounds.
Neoprene WHV-100Slightly lower in viscosity than WHV.
Medium crystallization speedNeoprene WBPolychloroprene containing a high proportion of gel forexceptionally smooth processing and very low nerve.Used in blends, typically to 25%, Neoprene WB giveshigh quality calendered sheet and smooth, collapse-resistant extrusions with low die swell.
Vulcanizates based upon WB resemble those fromother W-types for heat, ozone, oil and compression setresistance but give lower tensile and tear strengthsand flex crack/cut growth resistance with preferredW-type cure systems.
Very slow crystallizingNeoprene WRTA copolymer offering the maximum crystallizationresistance. It can require up to 50% more acceleratorto achieve the cure rate of Neoprene W. Vulcanizateshave rather lower tensile and tear strengths as com-pared with W.
Neoprene WDA high viscosity, crystallization resistant analogue ofWRT used where high levels of plasticizer wouldcause excessively soft compounds with that polymer.
T-TypesNeoprene T-types effectively combine the smoothprocessing of WB with the tensile properties ofNeoprene W. The three grades are:
Fast crystallizingNeoprene TWGenerally analogous to W but providing faster mixing,
smoother extrusion and calendering with slightly bettercrystallization resistance.
Neoprene TW-100Higher viscosity TW for greater extension without lossof processing advantages.
Very slow crystallizingNeoprene TRTAn analogue of WRT but with improved processingand crystallization resistance.
At a Glance Polymer Selection GuideTables 2, 3, 4 and 5 summarize basic details of theNeoprene types and grades. As previously indicated,there is a wide range of bulletins and data sheetscovering the products themselves, compounding,processing and end-use performance. These shouldalways be consulted prior to commencing work withNeoprene.
Basic PrinciplesBalanced compound based upon Neoprene G-, W-, orT-types will normally contain most of the classes ofingredients indicated in Table 5.
Acid Acceptors
High-Activity Magnesium Oxide (Magnesia)The primary function of the metal oxide is to neutralizetrace hydrogen chloride that may be liberated byNeoprene during processing, vulcanization and heataging or service. By removing the hydrogen chloride,it prevents auto catalytic decomposition hence greaterstability. Magnesium oxide also takes part in thevulcanization (cross-linking) process. Use of 4 partsmagnesium oxide and 5 parts zinc oxide generallyresults in a good balance of processing safety andcure rate and is typically used. Higher levels ofmagnesia may be desirable for high temperaturemolding, by injection. Lower levels of magnesia(2 pphr) may be used in some continuous vulcanizationcure systems. Suitable grades of magnesium oxide arefine particle precipitated calcined types with a highsurface activities measured by iodine number prefer-ably above 130.
Surface activity indicates the ability of the oxide toabsorb or react with hydrogen chloride, hence thehigher the value, the greater the processing safety andvulcanizate properties, especially with G-types.Neoprene G-type Mooney Scorch times ranging from54 down to 16 min for 10 pt rise at 121°C have beenrecorded, directly related to the activity of the magne-sium oxide incorporated.
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Table 3Neoprene W-Types
Raw polymer Non-PeptizableCompounds Excellent storage stability
Need acceleratorsVulcanizates Excellent heat resistance
Best compression set resistanceLower modulus
Grades ML4 — 100°C FeaturesW 40–49 General purpose (F)WM-1 34–41 Low viscosity W (F)WHV 106–125 Highest viscosity W (F)WHV-100 90–110 Lower viscosity WHV (F)WB 43–52 Gel-containing, smooth processing (M)WRT 41–51 Maximum crystallization resistance (VS)WD 100–120 High viscosity WRT (VS)(F) = Fast crystallizing (M) = Medium crystallization speed (S) = Slow crystallizing (VS) = Very slow crystallizing
Table 4Neoprene T-Types
Polymer, Compounds and Vulcanizates Basic properties of W-Types with the smooth processingLeast nerveNon-peptizable
Grades ML4 — 100°C FeaturesTW 42–52 Smoother processing than W (F)TW-100 82–99 Higher viscosity TW (F)TRT 42–52 Smoother processing than WRT (VS)
(F) = Fast crystallizing (VS) = Very slow crystallizing
Table 2Neoprene G-Types
Raw polymer Peptizable (except GW)Compounds Best tack
Fast curing without acceleratorsLimited storage stability
Vulcanizates High tear strengthBest flex crack/cut growth resistanceModerate heat resistanceModerate set resistance
Grades ML 1+4 at 100°C FeaturesGNA-M1 42–54 Better raw polymer stability (M)GNA-MZ 47–59GW* 28–49 Balanced blend of G & W properties, non-peptizable (S)GW-M1 28–38GW-MZ 37–49GRT* 30–52 High crystallization resistance/tack (S)GRT-M0 30–42GRT-M1 34–46GRT-M2 40–52(M) = Medium crystallization speed (S) = Slow crystallization*These ranges are maximum for the type. Subgrades with narrower viscosity ranges are available.
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Table 5Compounding Ingredients for Neoprene
Class TypicalAcid Acceptor Metal oxides
(1) High-activity magnesium oxide, MgO(2) Red lead, Pb3 O4
Vulcanizing Agent Zinc oxideVulcanization Accelerator (1) Thioureas for W and T-types, sometimes G
(2) Sulphur-based for W-typesVulcanization Retarder MBTS in G-Types, CBS, TMTD or MBTS in W-typesAntioxidant Octylated diphenylamineAntiozonant Mixed diaryl-p-phenylene diamines with selected waxes, to 3 phrFillers Carbon black; precipitated silica; calcium silicate; hydrated alumina; china clayPlasticizers Aromatic or naphthenic process oils; mono esters; polyester; chlorinated waxesProcessing Aids Stearic acid; waxes; low molecular weight polyethylene; high-cis polybutadiene; special factices
To prevent loss of surface activity in storage due topick up of atmospheric moisture or carbon dioxide,purchase in hermetically sealed sachets is recom-mended, as offered by most suppliers of high activityrubber grade of magnesium oxide (Mooney scorchtime at 121°C has been halved by exposure ofmagnesia to 50% relative humidity for 24 hr).
Alternatively, there are a number of commercialdispersions, typically 75% active powder, that exhibitgood storage stability. However, these may containmagnesia with a lower surface activity, hence careshould be taken in demanding conditions. Theymay also contain surfactants that can impair waterresistance.
Red LeadFor improved water resistance, a lead oxide,usually 20 parts of red lead Pb3O4, may replace themagnesia/zinc oxide combination. For healthreasons, it should always be added as a dispersion,90% in EPDM. Owing to more limited reactivitywith hydrogen chloride, stabilization is less efficienthence use is confined to Neoprene W- or T-types withsafe curing systems.
Calcium StearateThis substance has a limited use as an acid acceptor.Replacement of 4 parts magnesium oxide by anequimolar quantity (5.4 parts) of calcium stearate canretard hardening on heat aging and may be usefulwhere specifications call for hardness increase of 5 ptor less after 7 days at 100°C.
Vulcanizing AgentA good rubber grade of zinc oxide should be specifiedto minimize differences in curing activity.
Vulcanization AcceleratorsAs previously indicated, Neoprene G-types do notnormally require an organic accelerator to develop agood state of cure at acceptable rates. For faster cure,0.5 parts active ethylene thiourea (ETU) added as adispersion is suggested. Predictably, increased rateand state of cure, and reduced scorch resistance, areproportional to the amount added.
All Neoprene W- and T-types require an organicaccelerator.
Table 6 lists the common systems in order of increas-ing cure rate and decreasing processing safety.
The best balance of vulcanizate modulus, resilience,compression set and heat aging is normally given byETU. Processing safety can be improved by addingCBS or TMTD in carbon black stocks, or MBTS withmineral fillers such as china clay.
Where ETU is unacceptable even in dispersed form,use of Neoprene GW without accelerator may beconsidered where ultimate compression set resistanceis not required. At 170–180°C cure is usually suffi-ciently fast even for injection molding. Alternativeproprietary accelerators include dimethyl ammoniumhydrogen isophthalate, Vanax CPA. This may requirehigher amounts for equivalent cure rate. Informationon ETU-free alternatives are available on request.
Other possibilities include the TMTM, DPG or DOTG/sulphur systems where maximum resistance to heat orcompression set above 70°C is not required.
The best property balance is obtained using sulphur at0.5–0.75 parts with accelerator levels at 0.75–1.0 partof each. Scorch resistance and bin storage stability aregood. Addition of 0.3–0.5 parts ETU gives a fast cure
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rate with processing safety.
For continuous vulcanization up to 200°C or acceptablecure cycles at below-normal temperatures, up to 2parts DETU or DPTU may be specified. Such stocksare impractically scorchy for normal processing. Heathistory must be kept to a minimum and refrigeratedstorage is advised.
Water resistant Neoprene compounds containing redlead normally employ 0.5–1.0 part each of TMTM andsulphur as cure system. Acidic filers promote poorscorch and bin storage stability. Preferred ingredientsare furnace blacks or non-acidic clays.
Although they give very low compression set andgood processing safety, peroxide cures promote poorheat aging with Neoprene, even when high levelsof efficient antioxidants are incorporated. They arerarely used.
Table 6Acceleration Systems for Neoprene W- and T-Types
Ingredients Parts per 100 Neoprene Primary useA. Stocks containing 4 parts MgO, 5 parts ZnO
TMTM 0.5–1.0DOTG 0.5–1.0 Maximum processing safetySulphur 1.0–1.5
ETU* 0.55–0.75 Mineral filler loadingMBTS 0.5–1.0
ETU* 0.4–0.75 Carbon black loadingTMTD or CBS 0.5–1.0
TMTM 0.5DOTG 0.5 Medium to fast cure with moderate processing safetySulphur 1.0ETU* 0.2–0.4
ETU* 0.4–0.75 Maximum economyOptimum heat/compression set resistance
Methylthiazolidinthion 0.4–1.5 Substitute for ETU(CRV or MTT) Sometimes inconsistent cure, use higher level for high
carbon black loading.
Tributyl thiourea* 3.0 Excellent set and ozone resistance, non-stain
Trimethyl thiourea* 0.75–1.5 Excellent compression set resistanceEpoxy resin 1.0–2.0
Salicylic acid 1.0–2.0 High elongation/tear strengthLow discoloration under lead
Diethylthiourea* 1.0–2.0 Fast high temperature cures (LCM)(DETU) Practical cures at lower temperatures
DPTU* 1.0–2.0 As DETU(Thiocarbanilide)
Dicumyl peroxide (40%)* 1.5–2.0 Excellent set resistance and processing safetyN,N'-m-phenylenedimaleimide 1.5 (Poor heat aging with 4.0 magnesium oxide and 5 pphr
zinc oxide)
B. Stocks containing 20 parts red lead, Pb3O4*, no MgO or ZnOTMTM 0.5–1.0 Best water resistanceSulphur 0.5–1.0 Bin storage stability with alkaline fillers
*Active ingredient level. To be used as a dispersion.
Vulcanization RetardersIn Neoprene G-types, up to 1 part MBTS is aneffective retarder. It may also be added to allowprocessing of overaged polymer. MBTS, CBS orTMTD are effective retarders in Neoprene W- andT-types. Examples are given in Table 6.
Antioxidants and AntiozonantsUnlike unsaturated general purpose elastomers,Neoprene has inherent resistance to attack by oxygen,ozone, heat and light. However, long term optimumservice performance requires the addition of an effec-tive antioxidant and antiozonant.
Among possible antioxidants, octylated diphenylamine,2–4 parts, is preferred as it imparts the best heatstability, has no effect upon scorch or bin storage andis relatively nonstaining. Ketone amine and quinoline
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based types seriously affect scorch and bin storage andmust be avoided.
Effective antiozonants tend to adversely affect process-ing safety and to promote staining. Among para-phenylene diamine derivatives, mixed diaryl para-phenylene diamine has only a slight effect upon scorchand bin storage and gives the best balance of longterm protection, being non-extractable in water and oflow volatility. However, all PPD derivatives maycause migratory and contact staining of paintedsurfaces. Given the limited options for effectivenonstaining antiozonants, it is suggested that a DuPontDow Elastomers technical representative be consultedif one appears to be required.
Reinforcing and Extending Fillers
Carbon Blacks
As with all elastomers, Neoprene requires the additionof appropriate reinforcing fillers to achieve the re-quired balance of processability, hardness and tensileor tear properties. The most widely used is carbonblack.
Although the most highly reinforcing blacks N110(SAF) or N242, N220, N231, N219 (ISAF) can, underoptimized mixing conditions, give the best tensile andtear strength values, dispersion difficulties in practicelead to N330 (HAF) or N326 (HAF-LS) being thefinest particle carbons generally used. For mostapplications, N550 (FEF), N683 (APF), N660 (GPF),N772 or 774 (SRF) or N990 (MT) blacks, or blends,enable specification and service requirements to bemet. N550, N683 or N660, alone or blended withN772 or N774 are preferred for extrusion or calender-ing stocks. Where requirements permit, economicalcompounds may be prepared using high loadings ofN772 or N774 or N660 blacks, with significant levelsof plasticizer. Alternatively, blends of N772 or N774with mineral fillers such as china clay or whiting can beconsidered where compression set and physicalproperty requirements are modest.
Mineral Fillers
The most commonly used mineral fillers in Neopreneare precipitated silica, calcium silicate, china clay andwhiting. Hydrated alumina may be incorporated toraise ignition temperatures and limiting oxygen indexvalues.
Precipitated silica, preferably with up to 3 partstriethanolamine or other dispersing aid if used at highlevels, gives the highest levels of tensile strength,elongation and tear resistance. China clays may be hardor soft depending on the degree of reinforcement andloading required. Calcined clays are used for bestcompression set and electrical properties.
Whiting finds limited use as a cheap non-reinforcingfiller but it adversely affects weather resistance. Ifused, a stearate coated precipitated grade is prefer-able. Platy talc may be incorporated for good extru-sion and electrical properties.
PlasticizersAs with all elastomers, softeners, plasticizers andextenders are frequently added to Neoprene tofacilitate processing, enhance specific properties orreduce cost. Levels may be from 5 to more than 50parts. Care must be taken both in type selection andquantity to ensure that the attractive property balanceinherent in Neoprene is maintained.
Highly aromatic oils are compatible with Neoprene atall levels and are relatively low in cost. They increaseuncured tack at high dosage levels and can causevulcanizates to slightly stain paint films. Naphthenicoils do not have these effects and give better long-term heat resistance but their compatibility is limited toapproximately 15 parts maximum, depending upon thesource.
Ester plasticizers are required to maintain and increaseflexibility of Neoprene vulcanizates at temperatures to–40°C but tend to increase the crystallization rate ofsusceptible grades. Most commercial types such asthe sebacates, adipates, phthalates, phosphates andoleates may be used depending upon the necessarybalance of low temperature flexibility, volatility andcost. Di-2-ethyl-hexyl (di-octyl) sebacate (DOS) isoften used for its favorable combination of thesefactors. Butyl oleate is effective at low temperaturesbut relatively volatile at 100°C. Phthalates may be aneconomical choice where low temperature require-ments permit their use.
Polymeric plasticizers and hydrocarbon or coumarone-indene resins can retard crystallization but do notimprove low temperature flexibility. Phosphates tendto be used where self-extinguishing characteristics arecritical but low temperature flexibility less so.
Chlorinated hydrocarbons and waxes are availableboth in solid and liquid forms with chlorine contentbetween 40 and 70%. Liquid forms tend to cause moldsticking hence solid grades or blends tend to bepreferred. Their use is confined to Neoprene com-pounds with optimum ignition resistance or self-extinguishing characteristics.
Processing AidsSpecial low oil swell factices may be used in Neoprenecompounding, especially in low hardness compounds,for soft rollers. Such factices decrease compound nerve
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and may permit higher liquid plasticizer levels. Someloss of physical properties, especially compression set,is likely.
General purpose process aids include stearic acid,petrolatum (petroleum jelly), paraffin or microcrystal-line waxes and low molecular weight polyethylene.Stearic acid is particularly effective in minimizing milland calender roll sticking. To prevent significantretardation of cure rate, levels should be limited to1 part in W-type compounds, 2 parts in G-types.Typically, 1 part petrolatum, 1–3 parts wax or up to5 parts low molecular weight polyethylene may beincorporated. Note, however, that enhanced rollrelease with the latter requires temperatures abovethe softening point of the PE, 75–80°C. It is effectiveas an internal mold release agent, as are waxes.
High cis-1,4-polybutadiene at 3–5 parts providesmaximum roll release properties in very sticky stocks.Slight activation of cure will be observed.
For ease of mixing, reduction of structure and nerveand optimum physical properties in silica loadedNeoprene compounds, 3% of the silica content oftriethanolamine or calcium stearate should be included.Both should be added with a small amount of fillerearly in the mixing cycle. A typical application isextruded yellow mining cable.
Compounding for SpecificRequirements
Abrasion ResistanceIncorporate a fine particle size carbon black such asN330 or N326, typically up to 40 parts. N326, HAF-LS, is particularly useful where abrasion resistance isrequired with high resistance to tear and chipping.Plasticizers should be naphthenic and kept to a mini-mum hence G-type polymers such as Neoprene GWare preferable.
Adhesion to Substrates
MetalsWherever the required property balance permits,combinations of reinforcing blacks such as N330,N326 (HAF) etc. with 10 parts precipitated silica willenhance bond strengths. Plasticizer levels, preferablyaromatic oil or di-2-ethyl hexyl sebacate for lowtemperature flexibility, should be kept to a minimum.An excess of any plasticizer or process aid may impairbond strength.
All major suppliers of bonding agents offer oneor two-part primer systems for bonding Neopreneto ferrous or other metals. Table 9 gives a
non-exhaustive list of potential metal bondingprimers. The latter includes practical advice onmetal bonding in production.
A molding compound for bonding should have opti-mum acid acceptance derived from the correctselection of magnesia, its package and storage. Ifservice conditions involve extended high temperatures,6 parts magnesia and 10 parts zinc oxide should bespecified.
For nonferrous metals such as brass and zinc, directbonding without primer using 1.5 parts sulphur ispractical. In this case, ETU and derivatives should beavoided. With these substrates, inclusion of 5 parts ofa cobalt complex, Manobond C, is useful for higher,more consistent bond strengths.
Textile FibersAdhesion to fibers depends upon their nature. Nofabric treatment is normally required for cotton and alow viscosity Neoprene GRT will give maximumpenetration and wetting of a fabric or fiber. ForNylon or polyester, a primer coat of 30% Neoprenecompound solution in toluene containing 4–6% organicisocyanate is applied as a dip or spread coat.
The isocyanate treated fabric must be protectedfrom atmospheric moisture between dipping orspreading and final coating to ensure maximum bondstrength. For polyester tension members, as used inraw-edge V-belts, the cord supplier will normallypretreat with an isocyanate primer followed by aresorcinol-formaldehyde/vinyl pyridine/polychloroprenelatex dip.
Blending Neoprene With OtherElastomersBlends of Neoprene are sometimes used commer-cially, with natural rubber (NR) for hot tear strengthand building tack, styrene butadiene rubber (SBR) forcompound cost reduction and NBR for enhanced oiland fuel resistance. Careful compounding is necessaryto minimize modification of the overall unique blend ofproperties offered by Neoprene. It is important toremember that it is a relatively slow curing elastomerrequiring acceleration systems which are ultra fast forother diene elastomers. Selection of curing systemsfor the co-vulcanization of blends based upon Neo-prene must take into account the need for adequateprocessing safety and storage stability of the final fullcompound.
For consistent properties and performance, intimatemixing of the polymers is essential.
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Both polymers should be as close in viscosity aspossible. If flex fatigue and outdoor weatheringresistance are important factors, the split masterbatchmixing technique should be specified for intimateblending. This involves preparation of separatemasterbatches based on each blending polymer, withfiller and plasticizer adjusted to obtain a similarviscosity in each. The masterbatches are then blendedtogether thoroughly when the curatives are added.
NR, SBR and NBR in blends all adversely affect theozone resistance of Neoprene. It is essential to includeat least 2 parts of antiozonant, preferably of the mixeddiaryl type. For any blend with diene rubbers, Neo-prene W-types are preferred to G-grades sinceresidual thiuram disulphide in the latter causes poorprocessing safety. For blends with NR a combinationof 0.7 MBTS, 0.3 DPG, 2.0 sulphur is suggested. ForSBR blends cure systems based upon 0.5–1.0 TMTM,0.5–1.0 DPG, 1.0–1.5 sulphur are normal. An EVsystem based upon 1.0 DPG, 2.5 Tetrone® A will giveimproved heat resistance.
Blends with NBR are normally limited to 25 parts witha G-type of Neoprene using TETD 0.25–0.5as curative.
For polarity (compatibility) reasons, EPDM isnormally limited to 15–30 parts in blends withNeoprene to improve nonstaining static ozone resis-tance. Because of the incompatible nature of thepolymers, the split masterbatch mixing technique isconsidered essential. Curing systems for each polymerare added after blending and the following may beused: 0.5 TMTD, 1.0 MBTS, 0.3 TMTM, 1.0 sulphur.
The addition of up to 10 parts Neoprene W to resincured heat resistant IIR (butyl) compounds, e.g., fortyre curing bags, greatly reduces the tendency tosoften and lose mechanical strength during use.
Building TackLow viscosity Neoprene GRT gives the highestlevels of building tack. Where a W-type must beused, WRT or TRT are preferred. Aromatic plasticiz-ers give more tack than naphthenicor ester types. Other tack promoters are coumarone-indene resins, especially liquid types, wood rosinand phenolic resins such as Koresin. Aromatic oilsare more prone to cause troublesome roll stickingthan other types. As noted under Processing Aids,3–5 parts high-cis 1,4-polybutadiene can alleviateproblems of excessive roll sticking.
To maintain building tack no dusting agents shouldbe applied to sheeted stocks. Batch-off liners should benonstick.
Compression Set Resistance, Stress
Relaxation, Compression RecoveryTight cure of a crystallization resistant Neoprenegrade is fundamental to optimization of these proper-ties. Use Neoprene WRT or blends with WD formoldings, TRT if extrusion is involved. For the mostdemanding specifications, 3–4 parts TBTU are likelyto be preferred or 1.5 parts TMTU with 0.5–1.0 partepoxy resin to extend shelf life. TBTU also confersnonstaining ozone resistance used together with 2.0parts octylated diphenylamine. Most requirements canbe met using 1.0 part ETU, with DETU or DBTU forvery fast cures.
As in other areas, selection of the correct grade ofmagnesia is important. Among blacks, N990 mediumthermal usually gives the lowest set/stress relaxationvalues for a given level of addition but reinforcingblacks as previously listed, or blends, may be requiredto meet tensile or tear properties. Mineral fillers shouldbe avoided except where necessary at low levels, e.g.,to 15 parts precipitated silica when added for tearstrength or bonding.
For recovery from compression at low temperatures(–30 to –40°C) the minimum level of ester plasticizer,such as 10 parts DOS, should be used, with anyadditional plasticizer as aromatic oil. This is to balancethe crystallization-accelerating effect of the ester withthe retarding characteristic of the aromatic oil.
Creep ResistanceFor optimum creep resistance, compounding consider-ations apply except that plasticizers should be confinedto minimum levels of esters such as DOS. Extendedcures at moderate temperatures, 30 min or more at148–153°C, will ensure maximum cross-link densityfrom the vulcanization system selected.
Chemical ResistanceTo enhance resistance to swelling and degradation inaqueous aggressive chemicals and hot water or steam,use up to 20 parts active red lead as a dispersion, 90%in EPDM.
To avoid potential scorch problems, a W- or T-typepolymer should be selected, typically cured withTMTM 1.0 part and sulphur 1.0 part. To maintainprocessing safety, acidic fillers should be avoided. Forbest acid resistance, use 100 parts or more of barytesor blanc fixe. High plasticizer levels should be avoidedparticularly against oxidizing agents.
See also Water Resistance.
Crystallization Resistance
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For the best possible crystallization resistance, base thecompound upon Neoprene TRT, WRT or WD. Shoulda G-type be necessary for other reasons, GRT ispreferred but is not quite as resistant.
Preferred plasticizers are aromatic oils, or hydrocarbonresins such as Kenflex® A-1. Those are more effectiveas crystallization inhibitors in the uncured state. Esterplasticizers should be avoided but, if necessary forflexibility near the second order transition point (–30 to–40°C), use the minimum amount of DOS. Inclusionof up to 1 part sulphur will also retard vulcanizatecrystallization at the known expense of heat aging andcompression set resistance. Blends of Neoprene withup to 30% high cis-1,4-polybutadiene also showimproved crystallization resistance, with predictablediminution of tensile strength, oil, ozone and flameresistance.
Electrical PropertiesOwing to higher polarity versus totally hydrocarbonbased elastomers, Neoprene is not normally consid-ered a primary insulating material. To optimize itscapabilities, mineral fillers should be specified for theirhigher insulation resistance and dielectric strength ascompared with carbon blacks. Platy talcs such asMistron® Vapor are recommended for dielectricstrength. Ester plasticizers should be avoided. Up to15 parts naphthenic oil may be incorporated but ahydrocarbon resin, such as Kenflex® A-1, will optimizeinsulation resistance.
Where antistatic properties are essential, incorporationof conductive furnace blacks such as N283 (CF) orN472 (XCF) will achieve this, as in other elastomers.Care must be taken to select a safe processing curesystem in a Neoprene grade of sufficiently lowviscosity to minimize heat generation duringprocessing.
Flex Cracking ResistanceNeoprene G-types, especially GW or GRT, have thebest inherent flex fatigue resistance properties. GWmay be preferred where cut growth resistance is theprimary requirement. Wherever possible, compoundsshould contain N772 or N774 (SRF) carbon blacks, orblends with N990 (MT), for low modulus and highelongation. Up to 20 parts precipitated silica with adispersing aid will also assist. Acceleration of anypolymer grade with thioureas should be avoided.
Compounds should contain a good antioxidant/antiozo-nant system such as 2 parts octylated diphenylamine,1 part mixed diaryl p-phenylene diamine. All grades,G- or W-type benefit from inclusion of up to 2 partszinc 5-methylmercaptobenzimidazole (ZMMBI).This also acts as a heat stabilizer but may decreasecompound bin storage stability. Plasticizer should be
the minimum level of aromatic oil.
Excellent dispersion is essential if optimum flex fatigueproperties are to be achieved.
Flame ResistanceThe inherent self-extinguishing characteristics of allNeoprene grades may be enhanced or diminished bycompounding. Chlorinated paraffins varying between40 and 70% combined chlorine contents, solid or liquid,may be used both to plasticize and to increase theavailable chlorine level. To minimize the mill stickinessthese induce, polymers are normally higher viscosityW-types such as WD. Blends of solid and liquidchlorinated paraffins also reduce sticking tendencies.
Hydrated alumina enhances self-extinguishing charac-teristics and raises auto-ignition temperatures. It maybe used in combination with carbon blacks to achievetensile requirements. China clays and calcium silicateare also used but do not have the specific effects ofhydrated alumina.
Other additives to enhance self-extinguishing includeantimony trioxide, alone or preferably as a synergistic3:1 combination with decabromo biphenyl ether.Unacceptable afterglow promoted by antimonytrioxide can be prevented by inclusion of an intumes-cent crust forming agent such as zinc borate toexclude oxygen. Magnesium hydroxide finds use as asmoke suppressant. Hydrocarbon-based plasticizersand process aids should be avoided or severelyrestricted since they support combustion.
Food Contact
For actual list of rubber grades of Neoprene suitablefor use in compounds to meet the requirements ofU.S. FDA Regulation 21.CFR.177.2600 (rubberarticles intended for repeated use)—see “Guide forSafe Handling and FDA Status of Neoprene SolidPolymers."
Attention is drawn to limitations on compoundingingredients imposed in both FDA and BGA regulationsand to permissible extraction limits. ETU is not anacceptable accelerator. Information on alternatives toETU are available on request. Neoprene GWoffers a potential route to accelerator-free practicalcompounds, where the required balance of propertiespermits.
Heat Resistance
W- or T-type polymers are essential as they do notcontain free or combined sulphur. Use of 4–6 partshigh-activity magnesia (with up to 10 parts zinc oxide)is essential to achieve the highest level of acid accep-tance, especially where the Neoprene vulcanizate is incontact with natural or most synthetic fibers.
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The preferred antioxidant is 4–6 parts octylateddiphenylamine, with 1.5 parts mixed diaryl-p-phenylene diamine if high-ozone resistance isalso required. A tight cure is often essential to meetend-user specifications, and achieved with thioureaaccelerators.
Fillers are typically carbon blacks such as N550 (FEF)or N772 (SRF) or similar, alone or as blends or inconjunction with precipitated silica or reinforcingclays. Fine particle size calcium carbonate confersgood heat resistance but impairs physical properties,weathering and water resistance.
Selection of plasticizer type is important. Rapeseedoil or polyesters are recommended for permanence.Among monoesters, DOS is a preferred type for itsbalance of high and low temperature performance.Plasticizers to be avoided include butyl oleate andnaphthenic oils for their volatility, and aromatic oils.Use of 5 parts IIR rubber in a Neoprene compoundhelps counter the natural hardening of the polymeron long term exposure to high temperatures, as does5.4 parts calcium stearate substituted for the standard4 parts of high activity magnesia. Neither approach iscommonly adopted.
High ResilienceSpecify a G-type polymer, tightly cured. NeopreneGW is a good candidate and may meet requirementswithout additional acceleration. Among carbon blacks,N990 (MT) gives the highest resilience. Wherereinforcing types are essential, low structure variantsshould be specified.
Naphthenic oils or monoester plasticizers up to15 parts are preferred. Polyesters, resins of all typesand factices should be avoided.
If the overall required property balance permits itsinclusion, up to 20% of the polymer base as highcis-1,4-polybutadiene will enhance resilience. Thesplit masterbatch mixing technique is likely to benecessary and the possibility of problems due toscorch considered.
See also Vibration Damping.
High Strength at ElevatedTemperaturesPrecipitated silica up to 40 parts, preferably with upto 3 parts triethanolamine or other surface-activedispersing aid, is particularly effective in retainingvulcanizate physical properties at temperatures to200°C short term. Where extended exposure toelevated temperatures is also likely, the recommenda-tions for optimum heat resistance need to be followed.
Low-Gas PermeabilityPermeability constants for atmospheric gases suchas methane and hydrogen are lower for Neoprenethan NR or SBR at both 25 and 50°C. In practice,rate of permeation of a given gas may be significantlyaffected by compounding. Tight cure is a prerequisite,hence a Neoprene W-type with thiourea accelerationis preferred. Platy fillers such as mica or MistronVapor talc reduce permeability anisotropically. Withsignificant loadings of mica a lower viscosity polymergrade is likely to be required. Plasticizer levels shouldbe kept low and preferably avoided altogether.
Low-Temperature ResistanceBoth immediate stiffening as temperature is reducedand the slower effects of crystallization need to beconsidered. As temperatures decline, immediatestiffening occurs reaching a second order transitionat approximately –45°C when a phase change occursfrom the rubbery to the glassy state. When thisoccurs, Neoprene vulcanizates become brittle.Crystallization is slower and occurs most rapidly atapproximately –10°C. A rapid drop in temperaturecan prevent crystallization altogether, even in a fastcrystallizing grade, due to molecular immobilization.Both effects are reversible on warming but atdifferent rates.
During processing, crystallization may impair buildingtack after cool storage and give ply adhesion prob-lems. A typical in-service deficiency caused bycrystallization would be a conveyor belt that fails totrack adequately due to the resulting stiffening,thereby reducing its load carrying capacity. A degreeof crystallization can be beneficial for wire braidedhigh pressure hoses since the stiffer unvulcanizedextrudate better resists cutting in by the wire.
The principle factor in controlling the crystallizationrate in Neoprene is polymer selection, with W- orT-type copolymers as described under Types ofNeoprene, and Tables 3 and 4 being mandatory forthe very best resistance. As previously indicated,aromatic oils, polymeric or resinous plasticizers helpretard crystallization. Monoester plasticizers, essentialfor limiting short term stiffening and lowering thebrittle point, accelerate crystallization hence should berestricted to the minimum level necessary. Di 2-ethyl-hexyl (dioctyl) sebacate is very effective at lowtemperatures and nonvolatile up to 120°C.
In a 50 I.R.H.D. compound, approximately 15 partsare necessary for full flexibility at –40°C, 25 parts at 70+ I.R.H.D. Phthalate and phosphate based plasticizersare less effective but cheaper. Butyl carbitol formol(e.g., Thiokol TP90B) and butyl oleate are veryeffective but more volatile. The latter also tends toretard cure.
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Given the wide range of plasticizer types and variantsavailable, these notes can only be an outline guide. Ifalternatives to those mentioned are desired, suppliers’technical information should be reviewed.
Ozone ResistanceThe inherent ozone resistance of Neoprene maybe optimized by incorporation of antiozonants incombination with selected waxes, e.g., for externalapplications such as cable sheathing, structural gasketsand bridge bearing pads. Antiozonants should benonvolatile and non-extractable by water and haveminimum effect upon compound bin storage stability.
For moderate ozone test requirements, e.g., to 70 hrat 50 pphm, 38°C, 20% elongation, 2 parts octylateddiphenylamine with 3–5 parts of selected wax isusually adequate. For more demanding tests, e.g., to100 hr at 100 or 300 pphm, a mixed diaryl-PPDantiozonant should be specified, with the same level ofwax to maintain a protective surface film. Both typesof the chemical antiozonant confer slight paint staining.
Suppliers of specialized waxes for use as antiozonantsusually offer various grades depending upon test andservice temperatures. It is advisable to ensure that themost suitable grade has been selected.
Most monoester plasticizers adversely affect theozone resistance of Neoprene vulcanizates, with theexception of butyl oleate. This is beneficial, as is rawlinseed oil as a non-staining antiozonant which may,however, promote fungus growth. As noted inBlending, 15–30% EPDM may be substituted for partof the Neoprene polymer for nonstaining static ozoneresistance where other considerations allow.
Minimum Staining and DiscolorationAll colored Neoprene vulcanizates, especially lightpastel shades, discolor rapidly particularly whenexposed to strong sunlight. This may be acceptablewith solid colors obtained using 10–15 parts or more ofinorganic pigments such as red or yellow iron oxidesor chromium oxide green. Rutile titanium dioxide is themost effective UV screening pigment, used up to 50parts to mask discoloration in pastels. Eventually,some will occur.
For minimum discoloration, use W-types of Neoprenewith a phenolic nonstaining antioxidant. The G-typesshould be avoided.
Resistance to Lead PressDiscolorationThe primary cause of discoloration in lead curedcolored cable jacket compounds is interaction betweenthe metal and any available sulphur in the compound togive black lead sulphide. Hence a W-type polymer is
mandatory and any compounding ingredient containingor liberating sulphur during cure, e.g., TMTD-curedfactice, must be avoided. ETU/MBTS is the preferredaccelerator system. If discoloration still occurs,consider using 3.0 salicylic acid, 0.5 DOTG, 3.0 epoxyresin as the curing system or add 1.5 parts calciumstearate.
Tear ResistanceNeoprene G-types are inherently better than W-types,with GW being outstanding. They possess excellentflex fatigue resistance with usually adequate compres-sion set resistance. Among fillers, precipitated silicawith a dispersing aid is the best but other mineralssuch as silicates and hard clays may also give bettertear values than most carbon blacks, at the expense ofpoorer compression set resistance.
N326 (HAF-LS) carbon black can give a goodbalance of tear and set properties provided that gooddispersion is achieved. To assist this, oil additionshould be avoided during incorporation of the black.Resinous plasticizers such as coumarones or alkylaromatic, at 5 parts also help achieve optimumtear strength. Natural rubber, 10–20 parts, may alsoassist but inevitably diminishes oil and ozoneresistance.
Vibration DampingHigh-mechanical damping is diametrically oppositeto the requirements for high resilience. A typicalapplication is machinery mountings in a hot and/or oilyenvironment. Appropriate compounds are usuallyhighly filled with soft black, china clay and aromatic oilhence high Mooney Neoprene WHV or WHV-100are indicated. ETU acceleration is required forpractical cure times and minimum creep in service.
Water ResistanceAcid acceptance systems based upon 4 parts activemagnesia are often satisfactory for long term perfor-mance at or near ambient temperatures, especially insalt-containing sea water or similar. As previouslyemphasized, magnesia should be purchased as powderin sealed sachets, not as dispersed pastes unlesscarefully checked for possible effects upon swell.
Precipitated silica to 25 parts is useful for long termwater resistance being most effective with magnesia/zinc oxide cure systems. Up to 20 days at 70°C,water absorption with silica is fairly high followedby desorption to an equilibrium. Its use is not recom-mended in composites such as cable jackets.
For optimum swell and degradation resistance in hotwater up to 20 parts red lead Pb3O4 should replace themagnesia and zinc oxide, as described in ChemicalResistance.
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While red lead offers the best water resistance, using20–30 parts of hydrotalcite in place of red lead alsoyields improved water resistance.
Weather ResistanceThe main atmospheric factors are UV light andozone with temperature and humidity as contributors.UV light promotes surface crazing but a minimum15 parts furnace black such as N772 or 774 (SRF)provides complete protection. For colored Neoprenevulcanizates, the most effective screening pigments inorder are rutile titanium dioxide (30 parts) and red oryellow iron oxides (15 parts) but they are far lessefficient than carbon black. It is better to avoid longterm direct sunlight exposure of colored Neoprene orto use a veneer based upon Hypalon®.
Provision against ozone attack should follow recom-mendations. Attention is again drawn to the risk offungal growth on black or colored compounds contain-ing raw linseed oil as antiozonant, which can lead tosurface crazing.
Processing
GeneralCareful control of all mixing and processing operationswith Neoprene is essential if trouble-free, reproducibleproduction is to be achieved. The effects of heatexposure or history upon scorch times and flow fromall operations, including raw polymer storage, espe-cially with G-types, is cumulative. Mixing tempera-tures for fully compounded stocks should neverexceed 110°C. Thorough cooling of sheeted stocks tothe center is an important factor. Another is theselection of the correct viscosity grade of Neoprene atthe outset as this affects all subsequent processingoperations.
Open Mill MixingSalient points are:• Use correct batch weight, eg., at S.G. 1.4, 28 kg for
1.06 m rolls, 56 kg for 1.52 m, 95 kg for 2.13 m• Ensure a good supply of cooling water to the rolls
preferably temperature controlled or refrigerated inhot weather
• Where chilled water can cause surface condensa-tion on rolls before or between mixes, dry off withscrap or a nonaccelerated mix based on a hydrocar-bon elastomer
• Band the Neoprene on cool rolls (35–50°C) thenthe magnesia followed by antioxidants, retarders,stearic acid, silica, dispersion aids and color pig-ments. Unless the polymer is a G-type being sepa-rately peptized, no mastication period is required
• Add reinforcing fillers such as carbon blacks andsilica as soon as possible after this to ensure maxi-mum shear for good dispersion. Follow by soft fillerssuch as thermal blacks and minerals
• Depending on the amount of liquids to be incorpo-rated, either mix with the soft fillers or add sepa-rately after powders have dispersed
• Add release agents such as waxes, petrolatum orlow-molecular-weight polyethylene slowly to avoidbreaking the band
• Finally, add zinc oxide and accelerator preferably asdispersions. After incorporation, cut and blend sideto side a minimum of ten times. After slabbing off,cool thoroughly in forced air, a water spray ordipping in an antitack solution. Do not allow thestock to soak
• Store cooled stock at 30°C or less, totally dry; watermilled into compounds may cause serious lamina-tion problems in subsequent extruding, calenderingor molding operations
Two potential difficulties with open mill mixing are rollsticking and poor dispersion. Roll sticking may becaused by poor cooling, insufficient roll release agent,caking of powdered magnesia especially on rolls madedamp by condensation, use of certain types of hardclay, excessively soft and/or tacky stocks and pittedroll surfaces. Neoprene G-types are more prone to rollsticking than W- or T-grades. Where sticking ispersistent, addition of 3–5 parts high-cis 1,4-polybutadiene usually resolves it with some loss ofprocessing safety. Sticking may also be countered bydusting the back roll with zinc stearate. Note, how-ever, that zinc stearate should not be used for dustingNeoprene compounds after slabbing off. It is not assoluble in Neoprene as in hydrocarbon rubbers, hencecan cause poor knitting in molding or plying up.
Poor dispersion may result from addition of plasticizerswith fine particle blacks or silica, or cutting back whilstloose fillers remain in the nip. Magnesia or fillers thathave caked on the rolls are also difficult to dispersesubsequently.
Internal MixingThis is preferred to open mill mixing since less heathistory is normally involved. Salient points are:
• Ensure the mixer is clean by running a clean-outbatch of unaccelerated W-type Neoprene or nitrilerubber before starting
• Start with a load factor of 0.6 in calculating theapproximate correct batch weight, ie., watercapacity of the mixer x compound S.G. x 0.6. Asexamples, this gives batch weights of approximately60 kg for a 3A Banbury, 145 kg for a No. 9 mixer, at
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S.G. 1.4. Depending upon the extent of chamber androtor wear, and the nature of the mix, theoreticalloadings may need adjustment (usually upwards) toensure that the ram bottoms towards the end of themixing cycle with normal air pressure
• Use moderate rotor speeds and full flow of tempera-ture controlled water to minimize temperature rise.Start with a mixer temperature of approximately50°C
• Adopt the same order of ingredient addition as withopen mill mixing. Where blends are used, allow1 min extra polymer blending time. It is especiallyimportant to add magnesia and antioxidant early inthe mixing cycle after the polymer chips havemassed or, in the case of G-types after peptization,if practiced as a separate step
• Provided indicated stock temperatures do notexceed 100°C and the cure system is not too active,zinc oxide and accelerator may be added to themixer, preferably as dispersions, 1 minute beforedumping. If in doubt, they should be added on thedump mill or in a second pass
• Where machine wear is moderate, upside-downmixing may be considered, particularly for NeopreneW compounds with moderate filler and oil loadings.Properly used, this procedure can reduce mix timesby 50%
• Regardless of loading method, dump the batch at amaximum 110°C
• Dump mills fitted with stock blenders are recom-mended to complete dispersion mixing
In internal mixing, dispersion of soft fillers may not beaffected by simultaneous addition of oils. Thisachieves shorter cycles with less risk of the batchbreaking up. Highly extended Neoprene WHVcompounds may require a full upside-downprocedure, a 2-stage method and/or a loading factorof 0.65 to obtain sufficient initial volume in thechamber. A dump temperature above 105°C for clayloaded compounds helps minimize the content of cure-retarding moisture.
Potential problems in internal mixing of Neopreneinclude incipient scorch, failure to mass and contami-nation. Adherence to the established principles for theefficient internal mixing of any elastomer will usuallyavoid them.
Incipient scorch may result from incorrect batchweight, insufficient cooling water flow or too highwater temperature. Where a degree of wear is knownto exist, zinc oxide and accelerator dispersions shouldbe added on the mill.
Failure to mass or breakup during the cycle may resultfrom the machine being too cold, inadequate initialloading, the addition of lubricants too early in the cycleor excessive rotor to chamber clearance.
Cured pieces in the stock may result by contaminationfrom debris caught in the chute or a worn gate or dustseal. Apart from use prior to mixing Neoprene, aclean-out batch run between compound changes isgood practice. Good maintenance of the mixer and itscooling and temperature indicating systems is animportant factor.
Calendering
Sheeting
For preparation of calendered sheet or skim coatingfabric, compounds based upon Neoprene T-types,or blends containing WB, are preferred since thepresence of particulate gel reduces nerve and givessmoother sheets. Compound should be uniformlywarmed up on an open mill and ideally fed to thecalender nip by oscillating conveyor to ensure continu-ous, even distribution across the full roll width, with asmall rolling bank.
Salient points are:• Accurate roll temperature control is essential.
Typical temperature ranges for Neoprene G- andW- or T-type compounds for a 3-roll calender areshown in Table 7
• To ensure release from the center roll, 1-4 parts lowmolecular weight polyethylene should be incorpo-rated as the release agent
• Specify a scorch-resistant cure system• Re-rolling of calendered sheet is good practice as it
reduces any tendency of soft stocks to stick to theliner cloth and reduces heat history
• Embossed polyethylene film is not recommended asa liner as the pattern can print onto the calenderedsheet and cause air trapping. This can result in poorply adhesion in subsequent building operations.Cotton process liners are preferred
• Where the desired sheet thickness is too great toachieve in one pass without air trapping, plyingup on the bottom bowl with an auxiliary squeeze rollmay be adopted. With tough, tack-free stocks,a bottom bowl temperature of 90–100°C improvestack and ply adhesion and reduces shrinkage
Potential problems in sheet calendering include rollsticking, crows feet surface marking, variable gauge,shrinkage, surface blisters, ply blisters and ply separa-tion. Sticking is generally due to incorrect roll tempera-ture, insufficient release agent or inappropriate choice
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Table 7Typical Neoprene
Sheet Calendering Temperatures
Neoprene Type G W or T
Top Roll, °C 70–80 90–100
Center Roll, °C 50–60 70–90
Bottom Roll, °C 30–40 30–40
of base polymer, fillers and plasticizers. Owing to theirsurface smoothness, Neoprene T-types may be moreprone to roll sticking. 3–5 parts high-cis, 1,4-polybutadiene will prevent this.
Crows feet, variable gauge and high or erratic shrink-age can result from variable rate and/or temperatureof feed, excessive amounts of stock in the nip causingvariations in feed stock temperature, a nervy or highviscosity mix, incipient scorch or a combination ofthese.
Surface blisters can be caused by attempting tocalender too thick a gauge in one ply, by excessive rolltemperature and/or low viscosity compound. Plyblisters are usually the result of insufficient squeezeroll pressure or chilling of the plied sheet by too cold abottom roll. Tight wrapping in cloth liners for 24 hr willeliminate many small surface blisters.
Ply separation suggests too low a temperature on thecalender rolls, too high compound viscosity, incipientscorch, inadequate building tack or squeeze rollpressure, the use of embossed polyethylene liners or acombination of these factors.
FrictioningGuidelines for the successful frictioning of Neoprenecompounds include:• Use a G-type base polymer (low viscosity GRT)• Moderate load, with up to 60 parts carbon black,
35 parts aromatic oil• Maintain roll temperatures to ± 2°C. Typical
settings are: top roll 80–90°C, middle 60–70°C,bottom 80–90°C. Unlike NR, Neoprene usuallyadheres to the cooler roll. Where necessary, milkcoating can be used to ensure adhesion to thecenter roll
• As with all elastomers, dry and iron the fabricbefore introducing to the nip
Potential problems include picking of stock by thefabric, plucking, variable strike through and fabriccrushing. Picking usually indicates too hot a center roll.If the top roll tends to pluck stock from the center roll,
the top roll may be too cool. In second pass frictioning,plucking of the first side by the bottom roll suggeststhat this roll is too cold.
Variable strike through may be due to non uniformfabric or feed temperature or variable rate of feed.Ironing of the fabric will overcome the first factor.
Crushed fabric is primarily due to insufficient thick-ness of stock on the middle roll. This should beapproximately twice as thick as the fabric. Highviscosity or nervy stocks may cause crushing, espe-cially with lightweight fabrics.
Extrusion
Compounding
Gel-containing polymers such as Neoprene WB, TW,TRT and TW100, or blends, compounded ideally withN550 (FEF) black, give collapse resistant, low nerve,low die swell, smooth extruding compounds, with goodvulcanized properties. Where high levels of liquidplasticizer are specified, higher viscosity polymerssuch as TW-100, WHV and WD can maintaincollapse resistance. Blends of N550 (FEF) with N772(SRF) or other softer blacks may be considered forlower cost.
Although popular in Neoprene non-black stocks, chinaclay can promote die drag necessitating use of internalrelease agents and/or a higher green strength basepolymer. When precipitated silica is used for highvulcanizate tear strength, rough extrusion due tostructure formation may be prevented by incorporationof 3% on the silica level of triethanolamine, calciumstearate or other surface-active dispersing aids, addedto the mixer with some oil before addition of the silica.
Machine Characteristics and Operation
• Cold feed extruders, typically with L/D ratios of12:1 to 16:1, are preferred since they avoid labor-intensive variable heat history remilling and deliverstock to the die at uniform temperature and viscos-ity. This improves consistency of gauge control andfinish
• Cold feed vacuum extrusion is essential with fastcuring stocks for continuous vulcanization ofprofiles, e.g., by microwave, LCM or fluidized bedtechniques
• Screws should be constant diameter decreasingpitch, with compression ratios to 4:1, preferablycooled with temperature controlled water
• A typical temperature profile would be: feed20°C, barrel graduated to 60°C, head 70–80°C,die 90–100°C, screw 40–60°C
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• If a hot feed extruder must be used, compoundshould only be milled long enough for uniformplasticization. Avoid running on the rolls duringinterruptions in extrusion. Mechanical strip feed ispreferred to avoid screw starvation or overfeeding
• Dies should have tapered leads to improve flow andprofile definition
Potential extrusion problems and possible causesinclude:
Rough Extrusions
Typically caused by poor dispersion, contaminationduring prior processing, partial scorch, excessivenerve, cold stock, poor die geometry.
Excessive Die Swell
Typically due to high nerve (possibly from partialscorch), cold stock, lightly loaded compound, poordie geometry. Where the need for a gel-containingpolymer is concerned, Neoprene WB has the highestcontent. Gel contents of T-types are intermediate.
Porosity
May be the result of soft compound, a hot extruderbarrel and/or screw or insufficient back pressurebehind the die. Possible solutions include use of ahigher viscosity polymer, a screen pack behind thedie, a die with a longer land or a cooler screw.
Surging
Indicates variable back pressure on the die plate.Causes may include excessive clearance betweenscrew and barrel or too much lubricant in the com-pound. A screen pack and/or lower temperature onthe screw may assist.
Collapse
Caused by low viscosity compound or too hot anextrudate. A higher viscosity gel polymer such asNeoprene TW-100 or a blend may assist with orwithout a cold water quench immediately afterthe die.
Continuous Vulcanization of Extrusions
Neoprene W-types with active acceleration systemsshow a characteristic very rapid rise of modulus oncevulcanization commences, more so than with mostother high-volume elastomers. Coupled with thepossibilities to vary green strength and collapseresistance by blending of grades, it is possible toprepare compounds with high resistance to distortionon extrusion and on entering the heating medium andto porosity from internally-generated vapor pressure.
Four essentially atmospheric pressure profile CVsystems exist, i.e., microwave, hot air tunnels, LCMin an eutectic salt mixture and fluidized beds. Forbest results all require cold feed vacuum extrusion to
remove occluded air and addition of 6–10 partsdispersed calcium oxide to the compound asdesiccant.
Using microwave or LCM systems, a cure cycle of1 min at 200°C is not untypical necessitating use ofactive thiourea-based accelerators. DETU, DPTUor ETU at 1.0 part or more are commonly used. Themagnesia may be reduced from 4–2 parts to furtherenhance cure rate. Obviously, the processing safetyof such compounds is very limited necessitatingcareful control of storage times, temperatures and allprocessing steps to minimize heat history. Accelera-tors should be added immediately prior to extrusionand refrigerated storage used for full compounds.
Molding
General
Neoprene is amenable to molding by all three pro-cesses of the rubber industry, e.g., compression,transfer or injection. Problems tend to be those ofelastomer molding in general and yield to the samesolutions.
In accordance with best modern practice, moldsshould ideally be fitted with vacuum extraction, eitherinternally or by external chamber. In general extrudedblanks are preferred for compression molding as theypermit variation of shape and cross section with goodgauge and weight control and are relatively air free.
Where high hot tear strength is required for demolding,a G-type of Neoprene (i.e., GW) will often be pre-ferred. As discussed under Compounding, incorpora-tion of precipitated silica, up to 10 parts NR or syn-thetic polyisoprene or 5 parts of a hydrocarbon resinwill optimize demolding tear strength with any Neo-prene grade.
Ease of stripping may be enhanced by inclusion of2–3 parts low molecular weight polyethylene in thecompound and/or by light spray or aerosol applicationof proprietary external mold release agents. Excessiveuse of these may promote mold deposits hence thedesirability of spray application.
Compression Molding Troubleshooting
Some of the problems that can occur in the compres-sion molding of Neoprene and other elastomers, andpotential solutions, follow. These notes may also beapplicable to similar problems in transfer or injectionmolding.
Air or Pock Marking
May be caused by undercure, very low hot viscosity oroccluded air trapped on the surface. Depending on thecause, bumping the press, use of vacuum, faster cureand/or higher polymer viscosity may assist. The tool
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may need modification to improve venting if vacuumcannot be applied or is ineffective.
Air Blisters Below the Surface
May result from low viscosity stocks or plied-upblanks. Adjustment of the bump program or the blankshape factor to enhance flow may resolve with a givencompound.
Backgrinding
This is the phenomenon of tears or distortion at themold parting line often caused by localized expansionon pressure release. Large articles are more prone toit than small. Accurate blank weights, preheating,lower mold temperatures or a slower curing compoundmay all be beneficial, as may venting the tool to allowfor stock bleed during cure.
Distortion
Generally caused by undercure, partially set up stockor too high a mold temperature.
Excessive Shrinkage
Caused by incorrect allowance in the mold design,precure during flow or incipient scorch in the com-pound prior to molding. Reduction of moldingtemperature will assist, as may use of hard china clayas a principle filler.
Flow Cracks (poor knitting)
May be due to nerve, precure during flow, or very softcompound giving excessive flow before full clampingpressure is reached preventing achievement ofsufficient molding pressure. Presence in the compoundof excess internal process aids or limited compatibilityplasticizers can also impair knitting, as can externalmold release agents such as silicones, and too muchdusting agent on uncured blanks.
Pebbling or Orange Peel
This surface effect occurs mainly in gum or lightlyloaded stocks and is typically due to poor acceleratordispersion. If accelerators are added as dispersionsthe problem is unlikely to occur.
Porosity
Usually due to insufficient blank weight, porosityin the blank, undercure or compound incapable ofgiving a sufficiently high state of cure (hot modulus)at the molding temperature to resist the internal gaspressure.
Injection Molding
Regardless of polymer base, injection molding canoften offer improved productivity. Economics toproduce a given part may need careful consideration astool costs are higher, equipment more expensive
making nonoperating and down time more critical andoverall flexibility versus well-engineered compressionmolding is less.
Referring to potential problems described underCompression Molding preceding, two of these may bemore acute with injection, namely:
Air Trapping
Promoted by typically rapid mold filling. Correctmold venting usually with vacuum is a basic require-ment. Use of a higher viscosity Neoprene grade orblend is also recommended, sometimes with lowerbarrel temperatures.
Mold Fouling
Leading to sticking, ejection difficulties andvulcanizate surface marking.
Causes of fouling can be complex but it may beminimized by observing these guidelines:
1. Specify nickel-chrome tool steels.
2. Include at least 4 parts high activity magnesia,selected and stored as advised. If fouling occurs,increase to 6 or 8 parts.
3. Include an effective non-reactive internal moldrelease agent such as low molecular weightpolyethylene.
4. Insure plasticizers do not contain free acid, e.g.,phosphoric acid in tricresyl phosphate.
5. Set the highest barrel temperature consistent withsafe processing and freedom from precure in thebarrel so that the compound injects into the cavityat as high a temperature as possible. Once thecavity is filled, cure as rapidly as possible. Onecandidate curing system is 1.0 part ETU as adispersion with 0.75 CBS. The latter retards atbarrel temperatures (80–90°C) and activates atcuring temperatures.
6. Do not specify higher mold temperatures thanare necessary for efficient production. Typically,180–185°C is usually adequate, with an absoluteupper limit of 200°C.
Bonding During Molding
With the noted exception of nonferrous metals towhich compounds containing 1.5 parts free sulphur(where otherwise acceptable) will directly bond, aproprietary one or two-part primer system is normallyrequired. A selection from various sources is listed inTable 8 but this is not exhaustive either in terms ofsources or the systems on offer.
18
Table 8Primers for Neoprene/Metal Bonding
During Molding
Supplier Trade name One Coat Two Coat
Lord Corp. Chemlok® 250, 252, 205/220253, 254 205/236A
205/252
Rohm & Haas Thixon® OSN2 P11/511EF
C.I.L. Ltd. Cibond® 21T 11 to 12/50 or 5822
Chemetall GmbH Megum® 100 3270/10010576 3270/50011658 3270/1455014550
Some general principles include:
1. Ensure the metal surface is degreased and chemi-cally clean. Preparation for primer application maybe completed by grit or alumina blasting (ferrousand nonferrous metals) or proprietary phosphateetching/coating processes (ferrous metals).
2. Where indicated use any proprietary metal treat-ment recommended by the primer supplier.
3. Apply primer(s) as recommended by the supplierto the preferred film thicknesses where this isknown to be critical.
4. Store prepared or primed metals under non-humidconditions and use promptly.
5. After introducing primed metals to the mold,quickly load the compound blanks and close thepress.
6. With standard (non-positive) compression molds,ensure compound viscosity is sufficiently high tomaintain adequate cavity pressure for optimumbonding (this is not necessarily the same as rampressure).
7. Avoid unnecessarily high molding temperatures.
Note: Bonding primers are solvent-based systems.Suppliers’ safe handling information should beconsulted prior to use. Ensure also that use ofdegreasing solvents is in accord with local andnational requirements.
Open Steam Curing
As with all elastomers, profiles based upon Neoprenemay exhibit water spotting in open steam cure due topoorly located steam entry points, ineffective traps ora cold autoclave. Faster curing compounds are leastaffected. Curing in a dry preheated talc bed is
beneficial. Calendered sheet may be cured on drumswrapped in Nylon or cotton fabric in the conventionalway. High pressure CV cure of cable sheathing pre-sents no unusual problems.
Distortion or collapse of extruded profiles, especiallythin-walled sections, is minimized by use of gel-containing polymers such as WB or T-types, or blends,preferably compounded with carbon blacks such asN550 (FEF) or N683 (APF).
Porosity may be caused by moisture or entrained air inthe compound or too slow modulus rise. Inclusion ofcalcium oxide desiccant will scavenge the water. Airmay be eliminated by increased polymer viscosity, useof a screen pack behind the die to increase backpressure or by vacuum extrusion.
Information on European UnionDangerous Preparations Directive1999/45/EC related to Colophony SkinSensitizationColophony is classified as a skin contact sensitizerunder European Union Dangerous PreparationsDirective 1999/45/EC effective July 30, 2002. ThisDirective requires labeling of products that containcolophony at levels equal to or greater than 0.1% (referto the Directives for specific details). Solid (dry type)Neoprene adhesive grade products manufactured byDuPont Dow Elastomers L.L.C. contain about 4%colophony (CAS No. 8050-09-7). Toxicological testshave demonstrated that dry Neoprene is not a skinsensitizer. Because of this testing, dry Neoprenepolymer is not subject to mandatory labeling under theabove Directive despite the presence of the colophony.However, when these Neoprene adhesive gradeproducts are dissolved in organic solvents, thecolophony may still be present at concentrations up to0.8% depending on the solids content of the solutions.In the absence of data showing the adhesive is not askin sensitizer, the adhesive could be subject to theabove EU regulation.
We recommend that manufacturers and marketers ofadhesive solutions based on DuPont Dow’s Neoprene(dry type) adhesive grade products determine whetherthe colophony level is above 0.1%. If the manufacturedpreparation has a colophony content of less than 0.1%it will not be subject to mandatory labeling (providedno other constituents necessitate mandatory labeling).Manufactured preparations that contain highercolophony contents will require the labeling and/orcontainer notices described in the Directive.
19
Representative Formulations
Automotive Applications
Constant Velocity Joint Boot 50° Shore A
Neoprene WHV 35Neoprene WRT 65High-Activity Magnesia 4Octylated Diphenylamine 45-Methyl Mercaptobenzimidazole 1Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 2Stearic Acid 0.5SRF N772 Carbon Black 20MT N990 Carbon Black 50Dioctyl Sebacate 15Rapeseed Oil 10Zinc Oxide 5ETU Dispersion [75%] 1TMTD 1Cure: 15 min at 153°CTensile Strength, MPa 13.4Elongation, % 585Hardness, Shore A 50
Constant Velocity Joint Boot (VW 639)60° Shore A
Neoprene WHV 35Neoprene WRT 65High-Activity Magnesia 4Octylated Diphenylamine 45-Methyl Mercaptobenzimidazole 1Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 2Stearic Acid 0.5SRF N772 Carbon Black 50MT N990 Carbon Black 20Dioctyl Sebacate 20Rapeseed Oil 5Zinc Oxide 5ETU Dispersion [75%] 1TMTD 1Cure: 15 min at 153°CTensile Strength, MPa 14.5Elongation, % 500Hardness, Shore A 60
Constant Velocity Joint Boot 70° Shore A
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 45-Methyl Mercaptobenzimidazole 1Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 2Stearic Acid 0.5Low Structure Furnace Carbon Black 70Dioctyl Sebacate 25Zinc Oxide 5ETU Dispersion [75%] 0.63TMTD 0.5Cure: 15 min at 153°CTensile Strength, MPa 16.7Elongation, % 380Hardness, Shore A 70
Brake Boots (Girling Specification TD 1472)
Neoprene WRT 50Neoprene W 50High-Activity Magnesia 4Octylated Diphenylamine 4Microcrystalline Wax 2Stearic Acid 0.5SRF N772 Carbon Black 35Precipitated Silica 10Dioctyl Sebacate 7Zinc Oxide 5ETU Dispersion [75%] 0.5TMTD 0.5Cure: 15 min at 153°CTensile Strength, MPa 17Elongation, % 470Hardness, Shore A 60
Ball Joint Seals (Ehrenreich 1394 Specification)
Neoprene WD 50Neoprene GW 50High-Activity Magnesia 4Octylated Diphenylamine 3Mixed Diaryl Para Phenylene Diamine 1.5Microcrystalline Wax 2Stearic Acid 0.5SRF N772 Carbon Black 15MT N990 Carbon Black 40Dioctyl Sebacate 15Butyl Carbitol Formol 5Zinc Oxide 5ETU Dispersion [75%] 0.63TMTD 0.5Cure: 2 min at 180°CTensile Strength, MPa 15.6Elongation, % 770Hardness, Shore A 51
20
Brake Diaphragm
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 1.5Microcrystalline Wax 3Stearic Acid 0.5HAF N330 Carbon Black 30Dioctyl Sebacate 8Zinc Oxide 5MBTS 0.5Cure: 15 min at 153°CTensile Strength, MPa 20Elongation, % 700Hardness, Shore A 65
Spark Plug Boot (Vauxhall Spec. RS 221)
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 4Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 3Low M.W. Polyethylene 5Platy Talc 25SRF N772 Carbon Black 5Resinous Plasticizer 10Zinc Oxide 5ETU Dispersion [75%] 0.5Cure: 15 min at 153°CTensile Strength, MPa 18Elongation, % 700Hardness, Shore A 55
Rack and Pinion Steering Bellows(VW 520 66 Specification)
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 3Stearic Acid 0.5MT N990 Carbon Black 125Dioctyl Sebacate 15Aromatic Process Oil 15Zinc Oxide 5ETU Dispersion [75%] 0.5CBS 0.75Cure: 15 min at 153°CTensile Strength, MPa 10.2Elongation, % 600Hardness, Shore A 58
Flocked Channel Profile Continuous Cure(VW TL 52071)
Neoprene TW 70Neoprene TRT 30High-Activity Magnesia 2Octylated Diphenylamine 2Non-Staining Antiozonant 1Stearic Acid 0.5FEF N550 Carbon Black 45Calcium Silicate 30Non-Staining Factice 5Process Oil 15Calcium Oxide Dispersion 8Zinc Oxide 5DETU 1.25Cure: 15 min at 153°CTensile Strength, MPa 14.5Elongation, % 500Hardness, Shore A 60
Extruded Windscreen Wiper Blade
Neoprene TRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 1SRF N772 Carbon Black 50Dioctyl Sebacate 8Zinc Oxide 5ETU Dispersion [75%] 1Cure: 15 min at 153°CTensile Strength, MPa 17Elongation, % 400Hardness, Shore A 65
Molded Windscreen Wiper Blade
Neoprene WRT M1 100High-Activity Magnesia 4Octylated Diphenylamine 2Non-Staining Antiozonant 1.5Microcrystalline Wax 1.0Stearic Acid 0.5SRF N772 Carbon Black 60Zinc Oxide 53-Methyl Thiazolidine-Thion-2 1.5
Automotive Applications (continued)
21
Engine Mounting 60° Shore A
Neoprene WRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 0.5FEF N550 Carbon Black 20Precipitated Silica 10Coumarone Resin (liquid) 8Zinc Oxide 5ETU Dispersion [75%] 0.75CBS 0.75Cure: 15 min at 153°CTensile Strength, MPa 18Elongation, % 500Hardness, Shore A 60
Air Suspension Cell (inner liner and cover)
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 2Stearic Acid 2GPF N660 Carbon Black 50Dioctyl Phthalate 10Zinc Oxide 5Cure: 15 min at 153°CTensile Strength, MPa 17Elongation, % 550Hardness, Shore A 60
50° Shore ABridge Bearing Pad
Neoprene WRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 1Stearic Acid 0.5ISAF N220 Carbon Black 15Dioctyl Sebacate 10Zinc Oxide 5ETU Dispersion [75%] 0.7CBS 1.0Cure: 15 min at 153°CTensile Strength, MPa 20.0Elongation, % 570Hardness, Shore A 50
60° Shore ABridge Bearing Pad
Neoprene WRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 1Stearic Acid 0.5ISAF N220 Carbon Black 20Precipitated Silica 15Dioctyl Sebacate 10Zinc Oxide 5ETU Dispersion [75%] 0.7CBS 1.0Cure: 15 min at 153°CTensile Strength, MPa 20.9Elongation, % 580Hardness, Shore A 60
70° Shore ABridge Bearing Pad
Neoprene WRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 1Stearic Acid 0.5ISAF N220 Carbon Black 30Precipitated Silica 15Dioctyl Sebacate 10Zinc Oxide 5ETU Dispersion [75%] 0.7CBS 1.0Cure: 15 min at 153°CTensile Strength, MPa 20.6Elongation, % 460Hardness, Shore A 70
Highway Seal Joint (continuous cure)
Neoprene TRT 50Neoprene WD 50High-Activity Magnesia 2Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 1Stearic Acid 0.5Petrolatum 2Low M.W. Polyethylene 3HAF N330 Carbon Black 10FEF N550 Carbon Black 20SRF N772 Carbon Black 15Dioctyl Sebacate 5Aromatic Process Oil 18Calcium Oxide Dispersion 6Zinc Oxide 5DETU 1Cure: 1 min at 230°CTensile Strength, MPa 15.6Elongation, % 335Hardness, Shore A 60
Bridge Bearing Pads and Highway Seal Joint
Automotive Applications (continued)
22
High Physical Strength Cable Jacket
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 3Mixed Diaryl Para Phenylene Diamine 2Stearic Acid 1.5Low M.W. Polyethylene 2GPF N660 Carbon Black 5Hard Clay 45Naphthenic Process Oil 5Zinc Oxide 5Cure: 20 min at 153°CTensile Strength, MPa 23.9Elongation, % 955Hardness, Shore A 60Tear, Die C, N/mm 50
Insulation Compound for Extrusion or Molding
Neoprene WRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Microcrystalline Wax 4FEF N550 Carbon Black 20Hard Clay 80Whiting 30Aromatic Hydrocarbon Resin 20Petrolatum 3Naphthenic Process Oil 10Zinc Oxide 5ETU Dispersion [75%] 1MBTS 0.5Cure: 40 sec at 1.6 MPa [16 Bar] SteamTensile Strength, MPa 11.2Elongation, % 460Equivalent Vol. Resistivity, ohm·cms 1.25 x 1012
Grey-Colored Cable Jacket to VDE 0207:5GM3
Neoprene TW 100High-Activity Magnesia 4Octylated Diphenylamine 2Paraffin Wax 5Stearic Acid 0.5FEF N550 Carbon Black 0.5Rutile Titanium Dioxide 10Platy Talc 90Polyester Plasticizer 12Petrolatum 3Zinc Oxide 5ETU Dispersion [75%] 1.30MBTS 1Cure: 1 min at 1.58 MPa [15.8 Bar] SteamTensile Strength, MPa 14.0Elongation, % 660
Low-Emission Cable Jacket
Neoprene W 100High-Activity Magnesia 4Octylated Diphenylamine 2Non-Staining Antioxidant 1Paraffin Wax 1.5Stearic Acid 0.5Precipitated Fine Whiting 65Aluminum Hydroxide 65Antimony Trioxide (90%) 5Tricresyl Phosphate 20Zinc Oxide 5ETU Dispersion (75%) 1.5MBTS 1Cure: 3 min in 1.55 MPa (15.5 Bar) SteamTensile Strength, MPa 10.3Elongation, % 760Tear, N/mm 8.8Oxygen Index, BS 2782/1,% O 33.0Temperature Index, BS 2782/1,°C 310.0Smoke Emission, BS 6401Dm, flaming 360.0Dm, non-flaming 320.0Acid Gas Emission (HCl),IEC 754-1, HCl, mg/g (%) 35.9 [3.6]Corrosivity, VDE 0472 part 813, pH 3.4Conductivity, micro Siemens 240.0
Yellow Cable Jacket to VDE 0207 5GM5
Neoprene W-M1 100High-Activity Magnesia 4Octylated Diphenylamine 22-Mercaptobenzimidazole 0.5Paraffin Wax 3.25Reinforcing Silica 45Triethanolamine 0.540% Active Vinyl Silane A172 1.25Rutile Titanium Dioxide 5Tricresyl Phosphate 12Organic Yellow Pigment 1Zinc Oxide 5ETU Dispersion [75%] 1.3MBTS 0.5Cure: 8 min at 180°CTensile Strength, MPa 17.8Elongation, % 890Tear, DIN 53507, N/mm 22.6Tear, VDE 0472, N/mm 47.4
Cable Jackets
23
Heavy-Duty Cable Jacket to British Coal Specs188 & 504
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 2Paraffin Wax 4Stearic Acid 1.5GPF N660 Carbon Black 40Hard Clay 40Refined Bitumen 10Antimony Trioxide [90%] 3Naphthenic Process Oil 5Zinc Oxide 5MBTS 1.5Cure: 25 min at 153°CTensile Strength, MPa 13.2Elongation, % 840Hardness, Shore A 77Tear, ASTM D-470, N/mm 14.4
Low-Temperature Service Jacket –55°C(MIL-1-3930D)
Neoprene TRT 50Neoprene WHV-100 50High-Activity Magnesia 4Octylated Diphenylamine 4Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 4Stearic Acid 0.5RCF Carbon Black 25SRF N772 Carbon Black 30Dioctyl Sebacate 25Butyl Carbitol Formal 10Zinc Oxide 5ETU Dispersion [75%] 2MBTS 0.5Cure: 40 sec at 1.55 MPa [15.5 Bar] SteamTensile Strength, MPa 13.0Elongation, % 410Hardness, Shore A 55Tear, ASTM D470, kN/m 4.5
Flexible Cable Jacket Compound to HarmonizedSpec HD 22.1.S2:1992 Type EM2
Neoprene TW-100 100High-Activity Magnesia 4Octylated Diphenylamine 2Paraffin Wax 6Stearic Acid 0.5GPF N660 Carbon Black 20Hard Clay 40Coated Whiting 50Aromatic Process Oil 35Zinc Oxide 5ETU Dispersion [75%] 1.25TMTD 0.75Steam Cured in Flash Vulcanizer90 sec at 1.58 MPa [15.8 Bar]Tensile Strength, MPa 11.1Elongation, % 639Tear, BS 6899, N/mm 4.7
Heavy-Duty Cable Jacket toIPCEA-S-19-81 4.13.3 & 7.6.20.1.2
Neoprene TRT 40Neoprene WHV-100 60High-Activity Magnesia 4Octylated Diphenylamine 4Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 4Stearic Acid 0.5Low M.W. Polyethylene 1RCF Carbon Black 30SRF N772 Carbon Black 30Aluminum Hydroxide 30Dioctyl Sebacate 10Tricresyl Phosphate 30Zinc Oxide 5ETU Dispersion [75%] 2MBTS 0.5Tensile Strength, MPa 14.0Elongation, % 325Hardness, Shore A 60Brittle Point, °C –55
Cable Jackets (continued)
24
Welding Cable Jacket Harmonized StandardHD22.1.S2:1992 Type EM5
Neoprene TW-100 100High-Activity Magnesia 4Octylated Diphenylamine 4Microcrystalline Wax 5Stearic Acid 0.5FEF N550 Carbon Black 40Hard Clay 70Aromatic Process Oil 40Zinc Oxide 5ETU Dispersion [75%] 2MBTS 1Cure: 90 sec at 1.55 MPa [15.5 Bar] SteamTensile Strength, MPa 11.2Elongation, % 440
Cable Jackets (continued)
Cellular Products
Low-Density LCM Cellular Profile
Neoprene TW-100 65Neoprene TRT 35High-Activity Magnesia 2Octylated Diphenylamine 2Microcrystalline Wax 4Petrolatum 2SRF N772 Carbon Black 20MT N990 Carbon Black 50Factice 5Naphthenic Process Oil 20Calcium Oxide Dispersion 8Zinc Oxide 5DETU 1.5Azodicarbonamide Blowing Agent 4Cure: 20 m/min at 250°CDensity, g/cm3 0.55Compression Set, %, 22 hr at 70°C[40% Deflection] 29Water Absorption, % (Ford Method) 0.9
Chemically Blown, Non IntercellularSponge Sheeting
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 2Paraffin Wax 5Stearic Acid 0.5SRF N772 Carbon Black 60Naphthenic Process Oil 10Aromatic Process Oil 20Zinc Oxide 5Azodicarbonamide Blowing Agent 6P,P’-Oxy-bis Benzenesulphonyl Hydrazide 2Cure: 1st Stage: 10 min at 140°C
2nd Stage: 25 min at 170°C
Wet Suit Compound
Neoprene GW 100High-Activity Magnesia 2Octylated Diphenylamine 2Stearic Acid 0.5SRF N772 Carbon Black 15Calcium Carbonate 25Brown Factice 25Naphthenic Process Oil 15Zinc Oxide 5ETU Dispersion [75%] 0.5CBS 0.5Azodicarbonamide Blowing Agent 10Cure: 1st Stage: 8 min at 160°C
2nd Stage: 15 min at 170°CDensity, g/cm3 0.25
Low-Density, Open-Cell Sponge
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 2Paraffin Wax 5Stearic Acid 1Low M.W. Polyethylene (AC 617 A) 3MT N990 Carbon Black 40Sodium Bicarbonate (extra fine) 10Naphthenic Process Oil 10Aromatic Process Oil 20Zinc Oxide 5Cure: 20 min at 160°CMinimum Density, g/cm3 0.3
25
Airspring Compound
Neoprene GRT 100High-Activity Magnesia 5Octylated Diphenylamine 4Microcrystalline Wax 3Stearic Acid 2FEF N550 Carbon Black 40Coumarone Indene Resin 3Dioctyl Phthalate 5Naphthenic Process Oil 5Zinc Oxide 5MBTS 0.5Tensile Strength, MPa 18.7Elongation, % 620Hardness, Shore A 65
Military Tarpaulins or Life Rafts
Neoprene TRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Microcrystalline Wax 2Stearic Acid 0.5SRF N772 Carbon Black 30MT N990 Carbon Black 70Dioctyl Sebacate 15Zinc Oxide 5ETU Dispersion [75%] 0.6Tensile Strength, MPa 14Elongation, % 350Hardness, Shore A 60
Coating Compound
Neoprene WRT 100High-Activity Magnesia 4Non-Staining Antioxidant 2Microcrystalline Wax 1Stearic Acid 0.5Low M.W. Polyethylene 2SRF N772 Carbon Black 1Precipitated Silica 15Reinforcing Clay 60Rutile Titanium Dioxide 10Dioctyl Sebacate 20Zinc Oxide 5ETU Dispersion [75%] 1MBTS 0.75Tensile Strength, MPa 13.0Elongation, % 600Hardness, Shore A 57
Coated Fabrics
Neoprene Cement or Bonding Primerfor Nylon or Polyester
Mill Mix
Neoprene W 100High-Activity Magnesia 4Non-Staining Antioxidant 2Zinc Oxide 5
111
Churn Mix
Mill Mixed Batch 111Toluene 400Organic Isocyanate* 40
* add just before use
Seam Adhesive
Component A Mill Mix
Neoprene GNA-M1 100High-Activity Magnesia 4Non-Staining Antioxidant 2Calcium Silicate 10Zinc Oxide 5
121
Churn Mix
Mill Mixed Batch 121Toluene 359
480
Component B Parts per Hundred of Component A
Organic Isocaynate 8(shelf life 6 to 8 hr)
Solution Coating Compound
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 1Stearic Acid 1.5SRF N772 Carbon Black 55Graphite 20Coumarone Indene Resin (liquid) 10Aromatic Process Oil 10Zinc Oxide 5
26
Flame Retardant Impregnating Solutionto NCB 158/1960
For Nylon, Polyester or Blends with CottonNeoprene WRT 50Neoprene W 50High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 0.5SRF N772 Carbon Black 20Whiting 20Antimony Trioxide [90%] 25Calcium Metaborate 10Chlorinated Paraffin (liquid) 60Zinc Oxide 5ETU Dispersion [75%] 0.95Organic Isocyanate 7
Mill mix without chlorinated wax and isocyanate.Dissolve compound in toluene, add chlorinated waxand organic isocyanate. Adjust total solids to 20%(by weight).
Flame Retardant Inter Ply Skim Compoundto NCB 158/1960
Neoprene WRT 50Neoprene W 50High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 0.5SRF N772 Carbon Black 25Reinforcing Clay 40Whiting 20Antimony Trioxide [90%] 25Calcium Metaborate 1070% Chlorinated Paraffin (liquid) 3570% Chlorinated Paraffin (solid) 10Zinc Oxide 5ETU Dispersion [75%] 0.75
Candidate Anti-Static Cover Colored
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 2Chlorosiloxane 1Low M.W. Polyethylene 2Precipitated Silica 4056% Chlorinated Paraffin (liquid) 10Zinc Oxide 52-Mercaptobenzimidazole 0.5MBTS 0.5Polyethylene glycol 8Tensile Strength, MPa 19,0Elongation, % 995Hardness, Shore A 58Limiting Oxygen Index, % 31.0Volume Resitivity, µm·cm 3.6 x 103
Surface Resistance, ohm 8.4 x 1010
Candidate Anti-Static Cover Black
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 2Chlorosiloxane 1Low M.W. Polyethylene 2Precipitated Silica 4056% Chlorinated Paraffin (liquid) 10Zinc Oxide 52-Mercaptobenzimidazole 0.5MBTS 0.5Extra Conductive Carbon Black 5Tensile Strength, MPa 18.6Elongation, % 790Hardness, Shore A 75Limiting Oxygen Index 33.7Volume Resitivity, µm·cm 4.6 x 103
Surface Resistance, ohm 9 x 106
High-Limiting Oxygen Index Flame-Retardant CoverCompound
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 2Paraffin Wax 1Stearic Acid 0.5High cis Polybutadiene 4Fatty Alcohols Blend 3ISAF N220 Carbon Black 40Aluminium Hydroxide 30Antimony Trioxide [90%] 10Brominated Aromatic Oxide 1056% Chlorinated Paraffin (liquid) 1070% Chlorinated Paraffin (solid) 25Zinc Oxide 5MBTS 1Cure: 25 min at 153°C
Tensile Strength, MPa 18.5Elongation, % 590Hardness, Shore A 66Limiting Oxygen Index, % 47
Conveyor Belts
27
Lower Cost Cover Compound
Neoprene GW 60SBR 1500 40High-Activity Magnesia 3Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 3Microcrystalline Wax 1.5ISAF N220 Carbon Black 45Aluminum Hydroxide 25Antimony Trioxide [90%] 1.5Brominated Aromatic Oxide 556% Chlorinated Paraffin (liquid) 1070% Chlorinated Paraffin (solid) 25Zinc Oxide 5Sulphur 0.75MBTS 1Cure: 20 min at 153°CTensile Strength, MPa 19.7Elongation, % 560Hardness, IRHD 67Limiting Oxygen Index, % 33
Cover Compound to Meet NCB 158 Requirements
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 2Paraffin Wax 1Stearic Acid 0.5High cis Polybutadiene 4Fatty Alcohols Blend 3ISAF N220 Carbon Black 50Antimony Trioxide [90%] 156% Chlorinated Paraffin (liquid) 2570% Chlorinated Paraffin (solid) 10Zinc Oxide 5MBTS 1Cure: 25 min at 153°CTensile Strength, MPa 20.7Elongation, % 540Hardness, Shore A 65Limiting Oxygen Index, % 28
Candidate Adhesive Layer for Steel-Reinforced Belts
Neoprene WM-1 100High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 0.5High cis Polybutadiene 5ISAF N220 Carbon Black 25Precipitated Silica 20Aluminum Hydroxide 30Antimony Trioxide (90%) 10Decabromo Biphenyl Ether 1056% Chlorinated Paraffin (liquid) 1070% Chlorinated Paraffin (solid) 25Zinc Oxide 5TMTM 0.4DOTG 0.4Sulphur 2MBTS 1Steel-to-Rubber Bonding Agent 5Tensile Strength, MPa 17.8Elongation, % 590Hardness, Shore A 66Tear Strength, Die C, N/mm 54Limiting Oxygen Index, % 47
Conveyor Belts (continued)
28
Neoprene Non-Marking Sole
Neoprene W-M1 100High-Styrene Copolymer (85/15) 20High-Activity Magnesia 4Octylated Diphenylamine 1High cis Polybutadiene 3SRF N772 Carbon Black 1Precipitated Silica 25Reinforcing Clay 60Rutile Titanium Dioxide 5Naphthenic Process Oil 5Zinc Oxide 5ETU Dispersion [75%] 0.75TMTM 0.5DOTG 0.5Sulphur 1Cure: 10 min at 153°CTensile Strength, MPa 16Elongation, % 670Hardness, Shore A 85
Low-Cost Wellington Boot Sole
Neoprene W 50Natural Rubber 50High-Activity Magnesia 2Octylated Diphenylamine 2Stearic Acid 1.5Polyethylene Glycol 2SRF N772 Carbon Black 50MT N990 Carbon Black 50Aromatic Process Oil 15Zinc Oxide 5ETU Dispersion [75%] 1Sulphur 1.5TMTD 0.75Cure: 10 min at 153°CTensile Strength, MPa 13Elongation, % 250Hardness, Shore A 72
Neoprene Non-Marking Heel
Neoprene W-M1 100High-Activity Magnesia 4Octylated Diphenylamine 1High cis Polybutadiene 5SRF N772 Carbon Black 1Precipitated Silica 50Rutile Titanium Dioxide 5Naphthenic Process Oil 10Zinc Oxide 5ETU Dispersion [75%] 0.75TMTM 0.5Sulphur 1Cure: 10 min at 153°CTensile Strength, MPa 20Elongation, % 800Hardness, Shore A 71
Low-Cost Wellington Boot Upper
Neoprene W 50Natural Rubber 50High-Activity Magnesia 2Octylated Diphenylamine 2Stearic Acid 1.5Polyethylene Glycol 2MT N990 Carbon Black 50Dark Factice 20Aromatic Process Oil 15Zinc Oxide 5ETU Dispersion [75%] 1Sulphur 1.5TMTD 0.75Cure: 10 min at 153°CTensile Strength, MPa 11Elongation, % 570Hardness, Shore A 49
Footwear
29
Fuel Hose Cover Compound
Neoprene W 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 2Stearic Acid 1Petrolatum 2GPF N660 Carbon Black 60Hard Clay 90Dioctyl Sebacate 10Aromatic Process Oil 15Zinc Oxide 5ETU Dispersion [75%] 0.9TMTD 0.5Tensile Strength, MPa 11Elongation, % 400Hardness, Shore A 67
Fuel Hose Cover
3827Neoprene TW100 100Stearic Acid 1High Activity Magnesia 4Zinc Oxide 5Octylated Diphenylamine 2Zinc-2-Methyl meroaprobenzimidazale 1N762 80Ground Whiting 20Paraffin 2Low M.W. polyethylene 2Vanwax® H 2Tetraethylene Glycodi-2 ethylhexdate 15ETU dispersion (75%) 1
Total 235.5
30R7Spec.
Cured 25' at 160°CTb (MPa) 17 >7M-100 (MPa) 0.1Elongation, % 245 >200Hardness, Shore A 73
Tie Gum Compound
Neoprene W-M1 100High-Activity Magnesia 4Octylated Diphenylamine 2Calcium Stearate 4Low M.W. Polyethylene 4Precipitated Silica 40Epoxidized Soybean Oil 5Calcium Oxide 10Zinc Oxide 5TMTU 2
Brake Hose Cover Compound
Neoprene GW 70Neoprene WD 30High-Activity Magnesia 4Octylated Diphenylamine 4Mixed Diaryl Para Phenylene Diamine 2Stearic Acid 1FEF N550 Carbon Black 65Fine Particle Silica 8Dioctyl Sebacate 15Rapeseed Oil 8Zinc Oxide 5ETU Dispersion [75%] 0.66MBTS 1Tensile Strength, MPa 16.5Elongation, % 380Hardness, IRHD 70
Air Brake Hose Cover
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 1.5Paraffin Wax 1.5Stearic Acid 0.5MT N990 Carbon Black 170Butyl Oleate 5Aromatic Process Oil 20Zinc Oxide 5TMTM 1DOTG 1Sulphur 1Tensile Strength, MPa 12.5Elongation, % 325Hardness, Shore A 67
Hose Cover (DBL 5561/26)
Neoprene WHV 50Neoprene WRT 50High-Activity Magnesia 4Octylated Diphenylamine 4Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 2Stearic Acid 0.5FEF N550 Carbon Black 75Aromatic Process Oil 20Zinc Oxide 5ETU Dispersion [75%] 0.6MBTS 0.5Cure: 25 min at 160°CTensile Strength, MPa 15.7Elongation, % 275Hardness, Shore A 77
Hoses—Automotive Applications
30
Hose Cover to BMW 602 00.0/18/29Heat Resistant
Neoprene WD 100High-Activity Magnesia 5Octylated Diphenylamine 45-Methyl Mercaptobenzimidazole 2Mixed Diaryl Para Phenylene Diamine 2HAF N326 Carbon Black 55Butylenglycol Adipate 10Rapeseed Oil 10Zinc Oxide 5ETU Dispersion [75%] 1.5Cure: 15 min at 170°CTensile Strength, MPa 19.5Elongation, % 320Hardness, Shore A 67
Heater Hose to Ford SpecificationESA-M2D-157A
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 4Mixed Diaryl Para Phenylene Diamine 1Microcrystalline Wax 2Stearic Acid 1SRF N772 Carbon Black 30MT N990 Carbon Black 120Aromatic Process Oil 40Zinc Oxide 10ETU Dispersion [75%] 1.0TMTD 0.25Cure: 20 min at 153°CTensile Strength, MPa 12Elongation, % 340Hardness, Shore A 60
Radiator Hose to Ford SpecificationESE-M2D-116A
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 4Mixed Diaryl Para Phenylene Diamine 1Microcrystalline Wax 2Stearic Acid 1SRF N772 Carbon Black 40MT N990 Carbon Black 120Aromatic Process Oil 45Zinc Oxide 10ETU Dispersion [75%] 1.0TMTD 0.25Cure: 20 min at 153°CTensile Strength, MPa 11.7Elongation, % 280Hardness, Shore A 61
Audi Coupling Hose to VW 522-08
Neoprene WHV 80Polybutadiene 20High-Activity Magnesia 4Octylated Diphenylamine 1Mixed Diaryl Para Phenylene Diamine 2Stearic Acid 0.5FEF N550 Carbon Black 20SRF N772 Carbon Black 40MT N990 Carbon Black 30Dioctyl Sebacate 20Zinc Oxide 5TMTM 1DOTG 1Sulphur 1.5Tensile Strength, MPa 16.8Elongation, % 200Hardness, Shore A 72
Hose Cover (Heat Resistant) to DBL 6260Specification
Neoprene WD 100High-Activity Magnesia 4Octylated Diphenylamine 4Stearic Acid 0.5Low M.W. Polyethylene 2HAF N326 Carbon Black 25SRF N772 Carbon Black 40Precipitated Silica 10Coumarone Indene Resin 5Polyester Plasticizer 10Zinc Oxide 5ETU Dispersion [75%] 0.75CBS 1Cure: 15 min at 153°CTensile Strength, MPa 16.8Elongation, % 375Hardness, Shore A 65
Oil Suction and Discharge Hose Tube and Cover(Heavy Duty)
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 1.5Stearic Acid 1Low M.W. Polyethylene 2.5High cis Polybutadiene 3HAF N339 Carbon Black 50Coumarone Resin (liquid) 5Aromatic Process Oil 20Zinc Oxide 5MBTS 1Cure: 20 min at 153°CTensile Strength, MPa 20Elongation, % 500Hardness, Shore A 70
Hoses—Automotive Applications (continued)
31
Mining Hose Cover
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 2Low M.W. Polyethylene 3FEF N550 Carbon Black 50MT N990 Carbon Black 40Precipitated Silica 2042% Chlorinated Paraffin (liquid) 1070% Chlorinated Paraffin (solid) 5Tricresyl Phosphate 10Aromatic Process Oil 10Zinc Oxide 5TMTM 0.6DOTG 0.6Sulphur 1Tensile Strength, MPa 17Elongation, % 360Hardness, Shore A 70
Hydraulic Hose Cover Compound
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 1Stearic Acid 1SRF N772 Carbon Black 30MT N990 Carbon Black 170Aromatic Process Oil 15Rapeseed Oil 25Zinc Oxide 5ETU Dispersion [75%] 0.3TMTM 1DOTG 1.5Sulphur 0.3Tensile Strength, MPa 12.8Elongation, % 260Hardness, Shore A 70
Steam Hose Lining
Neoprene W 100High-Activity Magnesia 4Octylated Diphenylamine 2FEF N550 Carbon Black 15Precipitated Silica 25Aromatic Process Oil 5Zinc Oxide 5TMTM 1.5DOTG 0.5Sulphur 1Tensile Strength, MPa 24Elongation, % 650Hardness, Shore A 60
Fire Hose Liner Containing R/F Bonding Promotor
Neoprene TW-100 100High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 1Low M.W. Polyethylene 3MT N990 Carbon Black 20Precipitated Silica 30Brown Factice 10Butyl Oleate 7.5Aromatic Process Oil 7.5Zinc Oxide 5TMTM 0.5DPG 0.5Sulphur 1.5Adhesion Promotor 5Cure: 20 min at 153°CTensile Strength, MPa 16Elongation, % 800Hardness, Shore A 58
Railway Brake Hose
Neoprene WD 40Neoprene WRT 40Polybutadiene 20High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 2GPF N660 Carbon Black 80Dioctyl Sebacate 20Epoxidized Soybean Oil 0,5Zinc Oxide 5TMTM 1DOTG 0.75Sulphur 0.75Tensile Strength, MPa 14Elongation, % 280Hardness, Shore A 63
Vacuum Tubing (LCM Cure)
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 0.5FEF N550 Carbon Black 30SRF N772 Carbon Black 50Clay 30Dioctyl Sebacate 10Aromatic Process Oil 35Calcium Oxide Dispersion 8Zinc Oxide 15ETU Dispersion [75%] 1Cure: 15 min at 153°CTensile Strength, MPa 13Elongation, % 280Hardness, Shore A 70
Hoses—Non Automotive Applications
32
Welding Hose Tube and Cover
Tube CoverNeoprene TW-100 100 100Stearic Acid 1 2High Activity Magnesia 4 4Paraffin Wax 5Ground Whiting 60Microcrystalline Wax 2 2Octylated Diphenylamine 2 2N990 Black 140 —Hard Clay 60 11440% Chlorinated Paraffin (liq) 10 13Process Oil 10 5Zinc Oxide 5 5TMTM — 1DOTG 0.7 1.25Sulfur 0.4 0.25MBTS 1.2 —
396.3 254.5
Original Properties—30' at 320Tb (MPa) 8.4 9.7Elongation, % 211 810M100 (MPa) 6 1.2Durometer 89 55
Hose—Non Automotive Applications (continued)
Adhesion to Nylon Barrier
Neoprene WRT 100SBR 1502 3High Activity Magnesia 8Diphenylamine Derivative 1Low M.W. Polyethylene 3Fine Particle Silica 10N762 55Ppt. Hydrated Amorphous Silica 10Epoxy Resin, 72% 7Zinc Oxide 2Calcium Oxide Dispersion 3ETU Dispersion, 75% 1Hexamethoxymethylmelamine 5
263
Physical Properties (RT)Press Cured: 40 min at 160°CM100 (MPa) 2.8Tensile Strength (MPa) 7.9Elongation at Break, % 398Hardness, Shore A, pts 76
Miscellaneous
Compounds to Meet BS 2752
HardnessRange 41–50 51–60 61–70 71–80 81–88
Neoprene TRT 40 50 50 50 50Neoprene WD 35 50 50 50 50Neoprene WB 25 — — — —High-Activity
Magnesia 4 4 4 4 4OctylatedDiphenylamine 2 2 2 2 2
Paraffin Wax 1 1 1 1 1Stearic Acid 1 1 1 1 1FEF N550Carbon Black 10 25 50 55 75Brown Factice 5 5 10 10 10Dioctyl Sebacate 5 5 5 5 5Dioctyl Phthalate 10 10 10 5 5Zinc Oxide 5 5 5 5 5ETU Dispersion
[75%] 0.75 0.75 0.60 0.60 0.60TMTD 0.5 0.5 0.5 0.5 0.5
Cure: 20 min at 153°CTensile Strength,
MPa 13 17 19 18.9 19Elongation, % 660 480 340 310 230Hardness, IRHD 43 53 64 73 83
33
Cut Thread
Neoprene WRT 100Non-discoloring Antioxidant 2High Activity Magnesia 6Stearic Acid 0.5TiO2—Rutile 8Hard Clay 10Petroleum 2Low Mol. Wt. Polyethylene 3Zinc Oxide 3Salicylic Acid 2Cure: 30 min at 153°CVulcanizate Properties
500% Modulus, (MPa) 6.9Tensile Strength, (MPa) 20Elongation at Break, % 940Hardness, Durometer A 50
Gas-Mask, High Quality Formulation
Neoprene GW 100High-Activity Magnesia 4Octylated Diphenylamine 2Microcrystalline Wax 2Stearic Acid 2HAF N326 Carbon Black 15Naphthenic Process Oil 5
Zinc Oxide 5TMTD 1Cure: 15 min at 160°CTensile Strength, MPa 22Elongation, % 800Hardness, Shore A 60
General Purpose
Neoprene GW 100N330 Carbon Black 60Naphthenic Oil 5Petrolatum 2Stearic Acid 1Octylated Diphenylamine 1.5Mixed Diaryl Para Phenylene Diamine 1.5Zinc Oxide 5High Activity Magnesia 4
Total PHRs 180
Specific Gravity 1.4Original Physical PropertiesCure Time, min 20Cure Temperature, °C 160
Modulus at 100% Elongation, MPa 6.57Tensile Strength at Break, MPa 24.5Elongation at Break, % 270Shore A Hardness, pts 80(G1) Die “B” Tear Resistance, lb/in 313.6
Pump Impellor
Neoprene WRT 100Red Lead Dispersion [90%] 22Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 1.5Microcrystalline Wax 2SRF N772 Carbon Black 70Naphthenic Process Oil 5TMTM 1Sulphur 1Cure: 20 min at 153°CTensile Strength, MPa 16Elongation, % 400Hardness, IRHD 75
Heat-Resistant Compoundsto Meet DTD 5514 Specification
HardnessRange 45±4 55±4 65±4 75±4 85±4
Neoprene WRT 60 70 80 80 80Neoprene WB 40 30 20 20 20Calcium Stearate 5 5 5 5 5Octylated
Diphenylamine 4 4 4 4 4Petrolatum 1 1 1 1 1SAF N110Carbon Black — — — 35 50FEF N550Carbon Black 35 45 — — —SRF N772Carbon Black 25 — — — —Precipitated Silica — — — 15 25Dioctyl Sebacate 10 10 5 8 8Rapeseed Oil 15 10 7.5 — 8Peptizing Agent 2 — — — —Zinc Oxide 5 5 5 5 5ETU Dispersion
[75%] 0.75 0.63 0.75 0.75 0.75TMTD — — 0.70 0.70 0.70
Cure: 20 min at 153°CTensile Strength,
MPa 11.7 14.2 16 17.5 15.7Elongation, % 520 400 340 380 300Hardness, IRHD 41 54 65 73 83
Miscellaneous (continued)
34
Low Cost
5273Neoprene WHV 100Paraffin Wax 1Petrolatum 1Octylated D, phenylamine 2High Activity Magnesia 2N990 200N774 150Aromatic Process Oil 100Low M.W. polyethylene 3Zinc Oxide 5ETU Dispersion (75%) 1
Total Parts 565
Cured 26' at 160°CTb (MPa) 10.3M100 (MPa) 8.8Elongation at Break, % 115Hd (A) 81
ML (1+4) 100°C (µ) 74
Miscellaneous (continued)
Power Transmission Belts
Timing Belt Compound
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 3Mixed Diaryl Para Phenylene Diamine 1.5Stearic Acid 2Low M.W. Polyethylene (AC 617 A) 3SRF N772 Carbon Black 50Zinc Oxide 5TMTM 1Tensile Strength, MPa 20.5Elongation, % 350Hardness, Shore A 75
Adhesion Compound for V-Ribbed Belts
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 3Stearic Acid 1FEF N550 Carbon Black 20SRF N772 Carbon Black 20Precipitated Silica 20Process Oil 5Zinc Oxide 5ETU Dispersion [75%] 0.3Sulphur 0.5MBTS 0.75Resorcinol Bonding Promoter 5Formaldehyde Donor 2
Rib Compound for V-Ribbed Belts
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 3Mixed Diaryl Para Phenylene Diamine 2Microcrystalline Wax 1Stearic Acid 1FEF N550 Carbon Black 50Process Oil 5Zinc Oxide 5ETU Dispersion [75%] 0.3MBTS 0.75
Adhesion Compound for Raw Edge V-Belts
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 3Stearic Acid 1FEF N550 Carbon Black 20SRF N772 Carbon Black 20Precipitated Silica 20Process Oil 10Zinc Oxide 5ETU Dispersion [75%] 0.3Sulphur 0.5MBTS 0.75Resorcinol Bonding Promoter 5Formaldehyde Donor 2
35
Bottom Rubber Formulation for Raw Edge V-Belts
Neoprene GRT 90Neoprene WHV 10High-Activity Magnesia 4Octylated Diphenylamine 3Stearic Acid 1.5FEF N550 Carbon Black 20SRF N772 Carbon Black 20Polyester/Cotton Fibers (8 mm) 15Process Oil 5Zinc Oxide 5ETU Dispersion [75%] 0.3Sulphur 1.0MBTS 0.75
Adhesion Compound for Wrapped V-Belts
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 3Stearic Acid 1.5HAF N330 Carbon Black 20SRF N772 Carbon Black 25Fine Particles Silica 25Aromatic Process Oil 20Zinc Oxide 5Sulphur 1.5MBTS 0.5Tensile Strength, MPa 13.2Elongation, % 260Hardness, Shore A 79
Bottom Rubber Formulation for Wrapped V-Belts
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 0.5Stearic Acid 1.5Low M.W. Polyethylene (AC 1702) 2SRF N772 Carbon Black 30MT N990 Carbon Black 130Aromatic Process Oil 20Zinc Oxide 5Sulphur 1.5MBTS 0.5Tensile Strength, MPa 10.4Elongation, % 180Hardness, Shore A 84
Friction Compound for Wrapped V-Belts
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 1Stearic Acid 2MT N990 Carbon Black 60Coumarone Resin (liquid) 5Aromatic Process Oil 10Zinc Oxide 10Calendering Temperatures °CTop 125Middle 100Bottom 125
Pipe Gaskets (Not for Potable Water)
HardnessRange 45±4 55±4 65±4 75±4 85±4
Neoprene WRT 80 100 100 100 100Neoprene WHV 20 — — — —Red LeadDispersion [90%] 22 22 22 22 22Octylated
Diphenylamine 2 2 2 2 2Mixed Diaryl Para
Phenylene Diamine 1.5 1.5 1.5 1.5 1.5Microcrystalline Wax 2 2 2 2 2Stearic Acid 0.5 0.5 0.5 0.5 0.5Low M.W. Polyethylene 2 2 2 2 2Petrolatum 1 1 1 1 1SRF N772Carbon Black — 35 60 50 80MT N990Carbon Black 50 — — 40 30Aromatic Process Oil 30 12 15 12 12TMTM 0.75 0.75 0.75 0.75 0.5Sulphur 0.75 0.75 0.75 0.75 0.5Tensile Strength, MPa 12 17 16 15 15Elongation, % 680 640 420 320 200Hardness, Shore A 44 53 61 71 81
Power Transmission Belts (continued)
Profiles
Flame Retardant Profile
Neoprene TRT 50Neoprene TW-100 50High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 1Stearic Acid 0.5Low M.W. Polyethylene (AC 617 A) 3FEF N550 Carbon Black 30Platy Talc 6070% Chlorinated Paraffin (liquid) 25Tricresyl Phosphate 10Zinc Borate 5Calcium Oxide Dispersion 7.5Zinc Oxide 5DETU 1.25CBS 0.5Tensile Strength, MPa 13.4Elongation, % 410Hardness, IRHD 66
36
Continuously Cured Profiles
Neoprene TRT 50 35 50 35Neoprene TW-100 50 65 50 65High-Activity Magnesia 2 2 2 2Octylated Diphenylamine 2 2 2 2Microcrystalline Wax 2 2 2 2Stearic Acid 0.5 0.5 0.5 0.5Low M.W. Polyethylene
(AC 617 A) — 2 2 2FEF N550 Carbon Black — 20 50 70MT N990 Carbon Black 55 25 — —Aromatic Process Oil 50 25 15 20Calcium Oxide Dispersion 10 8 5 8Zinc Oxide 5 5 5 5DETU 1 1 1 1Tensile Strength, MPa 10.0 14.4 15.5 14.4Elongation, % 595 420 305 170Hardness, Shore A 35 55 67 76
Profiles (continued)
Roll Covers
Low-Hardness Printing Roll (15° Shore A)
Neoprene WHV 70SBR 1000 30High-Activity Magnesia 4Octylated Diphenylamine 2Paraffin Wax 1Petrolatum 1MT N990 Carbon Black 30Aromatic Process Oil 60Zinc Oxide 5ETU Dispersion [75%] 0.75Cure: 20 min at 153°CTensile Strength, MPa 7Elongation, % 760Hardness, Shore A 16
Low-Hardness Roll Non-Black (20° Shore A)
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 0.5Low M.W. Polyethylene 2Diatomite (surface treated) 20Triethylene Glycol Ester 50Zinc Oxide 5TMTU 1.5
Printing Machine Roll (25° Shore A)
Neoprene GRT 60Neoprene WHV 40High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 1.5Low M.W. Polyethylene 2MT N990 Carbon Black 20Factice 50Aromatic Process Oil 75Zinc Oxide 5Cure: 30 min at 160°CTensile Strength, MPa 6.8Elongation, % 600Hardness, Shore A 25
Paper Mill Roll (40° Shore A)
Neoprene GRT 70Neoprene WHV 30High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 1.5Low M.W. Polyethylene 2MT N990 Carbon Black 30Factice 20Aromatic Process Oil 40Zinc Oxide 5Cure: 30 min at 160°CTensile Strength, MPa 10.7Elongation, % 500Hardness, Shore A 40
37
Paper Mill Roll (60° Shore A)
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 1.5Low M.W. Polyethylene 2MT N990 Carbon Black 50Aromatic Process Oil 10Zinc Oxide 5Cure: 30 min at 160°CTensile Strength, MPa 14.3Elongation, % 450Hardness, Shore A 60
Water Repellent Rolls Non-Black (65° Shore A)
Neoprene TRT 50Neoprene WD 50Dibasic Lead Phosphate 20Non-Staining Antioxidant 2Microcrystalline Wax 2High cis Polybutadiene 3Rutile Titanium Dioxide 15Platy Talc 60Epoxy Resin 3Naphthenic Process Oil 10Zinc Oxide 10TMTU 0.75DOTG 0.5Cure: 20 min at 153°CTensile Strength, MPa 16Elongation, % 700Hardness, Shore A 65% Volume increase 14 days at 70°C 6
Water Repellent Rolls (65° Shore A)
Neoprene W-M1 100Red Lead Dispersion [90%] 20Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 1Microcrystalline Wax 3Petrolatum 2FEF N550 Carbon Black 20SRF N772 Carbon Black 20Reinforcing Clay 40Aromatic Process Oil 15TMTM 1Sulphur 0.75Cure: 20 min at 153°CTensile Strength, MPa 15Elongation, % 720Hardness, Shore A 65
Roll Covers (continued)
Abrasion Resistant Roll Cover (85° Shore A)
Neoprene GRT 100High Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 1.5Low M.W. Polyethylene 2HAF N330 Carbon Black 30MT N990 Carbon Black 20Precipitated Silica 20Coumarone Resin (liquid) 5Aromatic Process Oil 10Zinc Oxide 5TETD 1
Cure: 30 min at 160°CTensile Strength, MPa 17.8Elongation, % 400Hardness, Shore A 85
Roll Cover Non-Black (85-90° Shore A)
Neoprene GRT 100High Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 1Low M.W. Polyethylene 3Calcium Stearate 3Precipitated Silica 35Reinforcing Clay 55Coumarone Resin (liquid) 5Aromatic Process Oil 5Zinc Oxide 5ETU Dispersion [75%] 0.33
High Hardness Roll Cover (90° Shore A)
Neoprene WRT 100High Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 0.5SRF N772 Carbon Black 100MT N990 Carbon Black 40Naphthenic Process Oil 8Zinc Oxide 5TMTM 0.75DOTG 0.75Sulphur 1Cure: 20 min at 153°CTensile Strength, MPa 18Elongation, % 150Hardness, Shore A 93
38
Sheet Packing (50° Shore A)
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 2Paraffin Wax 1Petrolatum 1SRF N772 Carbon Black 50MT N990 Carbon Black 100Aromatic Process Oil 50Zinc Oxide 5ETU Dispersion [75%] 0.6Cure: 20 min at 153°CTensile Strength, MPa 12Elongation, % 300Hardness, Shore A 52
Sheet Packing (60° Shore A)
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 2Paraffin Wax 1Petrolatum 1SRF N772 Carbon Black 100MT N990 Carbon Black 100Aromatic Process Oil 75Zinc Oxide 5ETU Dispersion [75%] 0.6Cure: 20 min at 153°CTensile Strength, MPa 12Elongation, % 240Hardness, Shore A 60
Red Sheeting (60° Shore A)
Neoprene TW 75Neoprene TW100 25High-Activity Magnesia 4Non-Staining Antioxidant 2Microcrystalline Wax 2Stearic Acid 1Low M.W. Polyethylene 3Clay 60Platy Talc 25Naphthenic Process Oil 15Red Iron Oxide 5Zinc Oxide 5ETU Dispersion [75%] 1MBTS 0.5Cure: 20 min at 153°CTensile Strength, MPa 12Elongation, % 350Hardness, Shore A 60
Sheet Packing (70° Shore A)
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 2Paraffin Wax 1Petrolatum 1SRF N772 Carbon Black 150MT N990 Carbon Black 100Aromatic Process Oil 75Zinc Oxide 5ETU Dispersion [75%] 0.6Cure: 20 min at 153°CTensile Strength, MPa 10Elongation, % 150Hardness, Shore A 70
Sheet Packing (80° Shore A)
Neoprene WHV 100High-Activity Magnesia 4Octylated Diphenylamine 2Paraffin Wax 1Petrolatum 1SRF N772 Carbon Black 150MT N990 Carbon Black 200Aromatic Process Oil 100Zinc Oxide 5ETU Dispersion [75%] 0.6Cure: 20 min at 153°CTensile Strength, MPa 7Elongation, % 180Hardness, Shore A 80
Cork Sheet
Neoprene W-M1 100High-Activity Magnesia 4Octylated Diphenylamine 2Stearic Acid 0.5Clay 45Coumarone Resin 15Aromatic Process Oil 20Zinc Oxide 5ETU Dispersion [75%] 0.75TMTM 0.5DOTG 0.5Sulphur 0.75Ground Cork 100
Sheeting
39
Cork Sheet (Black)
Neoprene W-M1 100High-Activity Magnesia 4Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 1.5Stearic Acid 0.5MT N990 Carbon Black 35Coumarone Resin (liquid) 5Aromatic Process Oil 10Zinc Oxide 5ETU Dispersion [75%] 0.75TMTM 0.5DOTG 0.5Sulphur 0.75Ground Cork 100
Sheeting (continued)
Moisture Vapor Barrier Sheeting
Neoprene TW 100Red Lead Dispersion [90%] 22Octylated Diphenylamine 2Mixed Diaryl Para Phenylene Diamine 1.5Microcrystalline Wax 3Stearic Acid 0.5Petrolatum 1FEF N550 Carbon Black 60Aromatic Process Oil 12TMTM 1Sulphur 1Cure: 20 min at 153°CTensile Strength, MPa 12Elongation, % 400Hardness, Shore A 65
Tank Linings
Tie Gum
Neoprene WHV 100Neoprene W 100High-Activity Magnesia 4Octylated Diphenylamine 2Calcium Stearate 4Low M.W. Polyethylene 6Precipitated Silica 40Epoxy Resin 5Calcium Oxide 10Zinc Oxide 5TMTU 2Hardness, Shore A 75
Above is used as tie gum for Neoprene/Viton® laminatesalso for adhesion to brass and stainless steel wire reinforce-ment and for bonding Neoprene to Nylon and low-tempera-ture nitriles.
High Quality Tank Lining
Neoprene WRT 80Neoprene WB 20Red Lead Dispersion [90%] 22Octylated Diphenylamine 2Stearic Acid 1SRF N772 Carbon Black 50Aromatic Process Oil 10TMTM 1Sulphur 0.75Cure: 20 min at 153°CTensile Strength, MPa 14Elongation, % 800Hardness, Shore A 60
General Purpose Tank Lining
Neoprene TW 35Neoprene TRT 65Red Lead Dispersion [90%] 22Octylated Diphenylamine 2Stearic Acid 1SRF N772 Carbon Black 30MT N990 Carbon Black 60Coumarone Resin (liquid) 5Aromatic Process Oil 15TMTM 1Sulphur 1Cure: 20 min at 153°CTensile Strength, MPa 12Elongation, % 350Hardness, Shore A 65
Tie Cement
Neoprene GRT 100High-Activity Magnesia 4Octylated Diphenylamine 2FEF N550 Carbon Black 10Precipitated Silica 10Naphthenic Process Oil 4Zinc Oxide 5MBTS 0.5
Dissolve above in equal volumes of Toluene/Hexane/EthylAcetate to 25% total solids content.
40
High Abrasion Resistance Tank Lining
Neoprene TRT 65Neoprene TW 35Red Lead Dispersion [90%] 20Octylated Diphenylamine 2Stearic Acid 0.5Low M.W. Polyethylene 2ISAF N220 Carbon Black 40Aromatic Process Oil 15TMTM 1Sulphur 1Cure: 20 min at 153°CTensile Strength, MPa 20Elongation, % 450Hardness, Shore A 60
Tank Linings (continued)
Self Curing Tank Lining
Neoprene TRT 100Red Lead Dispersion [90%] 20Octylated Diphenylamine 2Low M.W. Polyethylene 2MT N990 Carbon Black 50Clay 15Process Aid 3Cond. Product of Acroleineand Aromatic Bases 2DPTU 2ETU Dispersion [75%] 1
41
Commercial Names of Ingredients
Specific compounding ingredients mentioned in this guide are listed below in alphabetical order.This is not to infer that comparable ingredients from other sources might not be equally satisfactory.Two sources are given for most materials, the first is European and the second is N. American.
Compounding Ingredient Commerical Name Supplier
Aluminum Hydroxide Hydral® 710 Alcoa
Antimony Trioxide (90%) Garoflam® Sb 90 P Omya UKFireshield® H Harwick Chemical Co.
Aromatic Hydrocarbon Resin Kenflex® A-1 Kenrich
Aromatic Process Oil Sundex® 790 Shell OilSundex® 790 R.E. Carrol
Azodicarbonamide Blowing Agent Multisperse E-Azok-75P Omya UKCelogen AZ Uniroyal
Blanc Fixe Barytes Sachtleben ChemieBarytes Whitacre
Brominated Aromatic Oxide Saytex® 102 Ethyl CorporationSaytex® 102E Albemarle Corp.
Butyl Carbitol Formal Thiokol® TP 90B Thiokol Corporation
Butyl Oleate Estol® 1414 UnichemaPlastHall 503 C.P. Hall
Butylenglycol Adipate Nycoflex® ADB 30 Safic Alcan
Calcium Metaborate Busari® 11 Buckman
Calcium Oxide Dispersion Deosec® Deutsche OelfabrikDesical® P Harwick Chemical Corp.
Calcium Silicate Ultrasil® 880 Degussa
Calcium Stearate Unem® 4850 UnileverCalcium Stearate Harwick Chemical Co.
CBS Vulcafor® CBS ICIDurax® R.T. Vanderbilt
40% Chlorinated Paraffin (liquid) Cereclor® 42 ICIChloro-flo® 42 Dover Chemical
56% Chlorinated Paraffin (liquid) Cereclor® 56 L ICIParoil® 5510 Dover Chemical
70% Chlorinated Paraffin (liquid) Cereclor® 70 L ICIParoil® 170LV Dover Chemical
70% Chlorinated Paraffin (liquid) Cereclor® 70 ICIChlorez® 700 Dover Chemical
Chloropropyl-Triethoxi Silane Silane® Sl 230 Degussa
Clay Speswhite English China ClayDixie Clay R.T. Vanderbilt
Coated Whiting Omya BSH Omya
Cond. Prod. Of Acroleine and Aromatic Bases Vulkacit® 576 Bayer
Coumarone Indene Resin Anchor MP 65P Anchor
Coumarone Resin (liquid) PLCT Anchor
DBTU Thiate® U R.T. Vanderbilt
DETU Robat® DETU PM Robinson Bros.Thiate®H R.T. Vanderbilt
Decabromo Bipheny Ether Flammex® B 10 Berk
Diatomite (surface treated) Celite® PF Lehmann & Voss
Dicumyl Peroxide Perkadox® BC Akzo ChemicalsVarox® DCP-R R.T. Vanderbilt
42
Compounding Ingredient Commerical Name Supplier
Dimethyl Ammonium
Diphenylamine Derivative Wingstay® 29 Goodyear
Hydrogen Isohthalate Vanax® CPA Vanderbilt
DPG Vanax® DPG Vanderbilt
DPTU A-l Thiocarbanilide Flexys
Dibasic Lead Phosphate Naftovin® T90 Chemson
Dioctyl Phthalate Bisoflex® DOP BP ChemicalsPlastHall DOP C.P. Hall
Dioctyl Sebacate Reomol® DOS FMCPlastHall DOS C.P. Hall
DOTG Vanax DOTG R.T. Vanderbilt
Epoxidized Soybean Oil Reoplast® 39 Ciba GeigyParaplex G62 C.P. Hall
Epoxy Resin Epikote® 828 Shell Chemicals
ETU Dispersion (75%) Robac 22 PM Robinson Bros.Poly-Dispersion END-75 Rhein Chemie
Extra Conductive Carbon Black Ketjen Black EC Ketjen CarbonEnsaco® 350 R.T. Vanderbilt
Fatty Alcohols Blend Vanfre® IL-2 R.T. Vanderbilt
Fine Particles Silica Ultrasil® VN3 DegussaUltrasil® 7000GR Degussa
Formaldehyde Donor Cohedur® A Bayer
Graphite Asbury 4078 Asbury Graphite
Hard Clay Suprex Clay Marlow ChemicalDixie Clay R.T. Vanderbilt
Hexamethoxymethylmelamine Cyrez 963 Cytec Industries
High Activity Magnesia Maglite® D C.P. Hall
High Cis Polybutadiene Buna® CB 10 Hols A. G.Buna® H Huls America Inc.
High Styrene Copolymer Duranit 15 BayerPliolite S6B Goodyear
Low M.W. Polyethylene AC 617A or AC 1702 Allied Chemicals
Magnesium Hydroxide Marinco® H Merck Chemicals
MBTS Altax® R.T. Vanderbilt
5-Methyl Mercaptobenzimidazole Vanox® MTI R.T. Vanderbilt
3-Methyl Thiazoidine-Thion-2 Rhenocure CRV LG Rhein Chemie
2-Mercaptobenzimidazole Naugard® MB Uniroyal
Microcrystalline Wax Vanwax® H R.T. Vanderbilt
Mixed Diaryl Para Phenylene Diamine Wingstay® 100 Goodyear
Napthenic Oil Sunthene® 4240 Sun Oil
Napthenic Process Oil Circo® Light Process Oil Sun Oil
N,N-m-Phenylenedimaleimide HVA-2 DuPont Dow Elastomers
Non-Staining Antioxidant Antioxidant 2246 American CyanamidVanox® MBPC R.T. Vanderbilt
Non-Staining Antiozonant Vulkazon® AFS Bayer
Octylated Diphenylamine Octamine UniroyalAgerite® Stalite S R.T. Vanderbilt
Paraffin Wax Vanwax® H Special R.T. Vanderbilt
P,P-Oxy-bis Benzenesulphony Hydrazide Celogen® OT Uniroyal
43
Peptizing Agent Vanax® 552 Vanderbilt
Phenolic Resin Koresin BASF/ StrucktolKoresin Strucktol of America, Inc.
Platy Talc Mistron Vapor® Cyprus ChemicalsMistron Vapor® Luzenac America, Inc.
Polyethylene Glycol Fatty Ether Antistaticum RC 100 Rhein Chemie
Polyester Plasticizer Diolpate® 214 Briggs & Townsend
Polyethylene Glycol Carbowax® 3350 Union CarbideCarbowax® 3350 Harwick Chemical Corp.
Precipitated Fine Whiting Calofort® U SturgeMultifex MM Specialty Minerals Inc.
Precipitated Silica Perkasit® KS 300 Akzo Chemie
Ppt. Hydrated Amorphous Silica Silene 732D PPG
RCF Carbon Black Raven 1040 Columbian Carbon
Red Iron Oxide Stan-Tone® Harwick
Red Lead Dispersion (90%) Kenmix® Red Lead/P Kenrich-StillmakePoly-Dispersion TRD-90 Rhein Chemie
Refined Bituman Mineral Rubber Lehmann & VossMineral Rubber Sovereign Chemicals Co.
Reinforcing Clay M501 English China ClayDixie Clay R.T. Vanderbilt
Resorcinol Bonding Promoter Cohedur RS Bayer
Rutile Titanium Dioxide Ti-Pure® R-960 DuPont
Salicylic Acid Retarder TSA MonsantoRetarder SAX Akrochem
Sodium Bicarbonate (extra fine) Natrimbikarbonat Malmsten & Bergvall
Steel-to-Rubber Bonding Agent Manobond® C Manchem Inc. UK
TBTU Robac® TBTU Robinson Bros.
TETD Robac® TET Robinson Bros.Ethyl Tuads R.T. Vanderbilt
Tetraethylene Glycol 2-ethylhexoate TegMer® 804 C.P. Hall
TMTD Robac® TMT Robinson Bros.Methyl Tuads R.T. Vanderbilt
TMTM Robac TMS Robinson Bros.UNADS R.T. Vanderbilt
TMTU Thiate® EF-2 R.T. Vanderbilt
Tricresyl Phosphate Pliabrac TCP FMCKronitex® TCP C.P. Hall
Triethanolamine Triethanolamine Harwick
Triethylene Glycol Ester Bisflex® 102 BP ChemicalsTegmer® 903 C.P. Hall
Vinyl Silane Vinyl Silane A 172 Union CarbideVinyl Silane A 172 Harwick Chemical Co.
Zinc Borate Firebrake® ZB 2335 Harwick
Zinc 5-Methyl Mercaptobenzimidazole Vanox® ZMTI R.T. Vanderbilt
Zinc Stearate Unem 4840 UnileverZinc Stearate Synpro
Compounding Ingredient Commerical Name Supplier
(01/04) Printed in U.S.A.Reorder No.: NPE-H77650-00-D0104
The information set forth herein is furnished free of charge and is based on technical data that DuPont Dow Elastomers believes to be reliable. It is intended foruse by persons having technical skill, at their own discretion and risk. Handling precaution information is given with the understanding that those using it will satisfythemselves that their particular conditions of use present no health or safety hazards. Since conditions of product use and disposal are outside of our control, wemake no warranties, express or implied, and assume no liability in connection with any use of this information. As with any material, evaluation of any compoundunder end-use conditions prior to specification is essential. Nothing herein is to be taken as a license to operate or a recommendation to infringe on any patents.While the information presented here is accurate at the time of publication, specifications can change. Please check www.dupont-dow.com for the most up-to-dateinformation.
Caution: Do not use in medical applications involving permanent implantation in the human body. For other medical applications, discuss with your DuPont DowElastomers customer service representative and read Medical Caution Statement H-69237.
AquaStik® is a registered trademark of DuPont Dow Elastomers.
Copyright © 2000–2003 DuPont Dow Elastomers. All Rights Reserved.
For further information on Neoprene or other elastomers please contact one of the addresses below, orvisit us at our website at www.dupont-dow.com
Geneva – EuropeanHeadquartersDuPont Dow Elastomers S.A.2, chemin du PavillonCH-1218 Le Grand-Saconnex,Geneva, SwitzerlandTel. +41-22-717 4000Fax +41-22-717 4001
FinlandOy Algol ABNuutisarankatu 15FI-33900 TempereTel. +358-3-266 1948Fax +358-3-266 0212
FranceSafic-AlcanDépartementDuPont Dow Elastomers3, rue BelliniF-92806 Puteaux CedexTel. +33-1-46 92 64 32Fax +33-1-46 67 04 42
GermanyDuPont Dow Elastomers GmbHDuPont Strasse 1D-61343 Bad HomburgTel. +49-6172-87 13 55Fax +49-6172-87 13 51
ItalyDolder-MassaraVia Caduti Bollatesi 38/b20021 Bollate (MI) ItalyTel. +39-02-350081Fax +39-02-38300725
South & CentralAmerica HeadquartersDuPont Dow Elastomers Ltda.Alameda Itapecuru, 506 - Sala 12Alphaville - Barueri - SPCEP 06454-080BrasilTel. +55-11-4166-8978Fax +55-11-4166-8989
PortugalSafic-Alcan Portugal LdaRua D. Marcos da Cruz 1351P-4455-482 PerafitaTel. +351-22-999 82 90Fax +351-22-960 01 31
SpainSafic-Alcan Espana, S.A.Division IsisaRocafort, 241-243E-08029 BarcelonaTel. +34-93-322 04 53Fax +34-93-410 69 78
SwedenNordica Elastomers ABHamntorget 1P.O. Box 10104S-43422 KungsbackaTel. +46-300-73 250Fax +46-300-73 251
SwitzerlandDolder AGImmengasse 9CH-4004 BaselTel. +41-61-326 66 00Fax +41-61-322 47 81
Singapore – Asia PacificHeadquartersDuPont Dow Elastomers Pte Ltd.1 Maritime Square #10-54HarbourFront CentreSingapore 099253Tel. +65-6275 9383Fax +65-6275 9395
JapanDuPont Dow Elastomers, Ltd.Dempa Bldg. 3F, 11-15Higashi-gotanda, 1-chomeShinagawa-kuTokyo, Japan 141-0022Tel. +81-3-3444-5166Fax +81-3-3444-6095
Korea OfficeDuPont Dow Elastomers Ltd.5th Floor, Asia Tower#726, Yeoksam-dong, Kangnam-kuSeoul 135-082, KoreaTel. 82-2-2222-5440Fax 82-2-2222-5485
USA – GlobalHeadquartersDuPont Dow Elastomers L.L.C.300 Bellevue Parkway, Suite 300Wilmington, DE 19809Tel. +1-800-853-5515
+1-302-792-4000Fax +1-302-792-4450
AustriaDolder GmbHBrucknerstrasse 6/2/5AA-1040 WienTel. +43-1-504 21 80Fax +43-1-504 21 93
BeneluxN.V. Sepulchre S.A.19, av. des NénupharsB-1160 BruxellesBelgiumTel. +32-2-672 23 35Fax +32-2-673 67 82
DenmarkNordica A/SPilestraede 43Postbooks 2241DK-1019 Kobenhavn KTel. +45-3315 2855Fax +45-3315 2161
