PLA Processing Guide for Bicomponent Staple...
Transcript of PLA Processing Guide for Bicomponent Staple...
PLA Processing Guide for Bicomponent Staple Fibers
This information is intended for use only as a guide for the manufacture of PLA fibers. Because melt spinning and downstream processing of PLA fibers is complex, an experimental approach may be required to achieve desired results. 1.0 Safety and Handling Precautions All safety precautions normally followed in the handling and processing of melted thermoplastics should be followed for NatureWorks® PLA resins. As with most thermoplastics, melt processing and the variability of those conditions may result in minor decomposition. Lactide, a non-hazardous gaseous irritant, is a minor by-product of PLA melt processing. Appropriate air testing should be completed to ensure an acceptable Threshold Limit Value (TLV) of less than 5 mg/m3 is maintained. The use of process area point source remediation measures such as monomer fume hoods or exhausts near the spinneret are typically recommended. PLA is considered non-hazardous according to DOT shipping regulations. Care should be taken to avoid direct skin/eye contact along with conditions that promote dust formation. Product may cause eye/skin irritation. Product dust may be irritating to eyes, skin and respiratory system. Caused mild to moderate conjuctival irritation in eye irritation studies using rabbits. Caused very mild redness in dermal irritation studies using rabbits (slightly irritating). Ingestion may cause gastrointestinal irritation, nausea, vomiting and diarrhea. For further information, consult the appropriate MSDS for the PLA grade being processed. 2.0 Pellet Storage and Blending Recommendation PLA resins should be stored in an environment designed to minimize moisture uptake. Product should also be stored in a cool place at temperatures below 50°C (122oF). Product that is delivered in cartons or super sacks should be kept sealed until ready for loading into the blending and/or drying system. Bulk resin stored in silos, hoppers etc for extended periods (more than 6 hrs) should be kept purged with dry air or nitrogen to minimize moisture gain. In the case of outside storage, if the product is supplied in Boxes or other non-bulk containers, the unopened container should be brought into the fiber production area and allowed to equilibrate for a minimum of 24 hours before opening. 3.0 Resin Properties Different grades of PLA have been designed for different types of bicomponent fibers
Resin Grade Resin Use 6201D High melt temperature, mid viscosity, low-
shrink component used for cores in S/C, 1 side in S/S or segment in Pie/Wedge or as a
component in Islands in the Sea Fibers 6251D High Melt temperature, low viscosity, low
shrink component used for cores in S/C, 1 side in S/S or segment in Pie/Wedge or as a
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component in Islands in the Sea Fibers 6301D Low Melt temperature, mid viscosity,
higher shrink component for sheaths in S/C, 1 side in S/S or segment in Pie/Wedge
or as a component in Islands in the Sea 6350D Low Melt temperature, low viscosity,
higher shrink component for sheaths in S/C, 1 side in S/S or segment in Pie/Wedge
or as a component in Islands in the Sea 6400D High melt temperature, high viscosity, low
shrink component for cores in S/C, 1 side in S/S or segment in Pie/Wedge or as a
component in Islands in the Sea 6800D High melt temperature, high viscosity, low
shrink component for cores in S/C, 1 side in S/S or segment in Pie/Wedge or as a
component in Islands in the Sea Other grades Grades normally intended for packaging
have been evaluated in all applications mentioned above-S/C, S/S, P/W, IITS
Table of Resin Grades
Peak Fiber Crystalline MT vs. %D
MT = -4.366%D + 174.78R2 = 0.9758
0.0
20.0
40.0
60.0
80.0
100.0
120.0
140.0
160.0
180.0
0 2 4 6 8 10
%D
Peak
Cry
stal
line
Mel
t Tem
p (o
C)
12
Relationship of Melt Tempature to %D
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Typical PLA Resin Properties The graph on the following page shows the melt density of PLA over a wide temperature range.
PLA M elt Density Curve
1.050
1.060
1.070
1.080
1.090
1.100
1.110
1.120
1.130
1.140
1.150
1.160
140 150 160 170 180 190 200 210 220 230 240 250
Tem p (oC)
Mel
t Den
sity
(g/c
c)
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The rheology curves for several of these grades are shown in the following graph.
Fiber Grades Rheology Example, 230 oC
10
100
1000
10 100 1000 10000 100000
Shear Rate, /sec.
ShearViscosity,Pa.s
6251D, 2.4 RV6201D, 3.1 RV6201D, 3.1 RV6201D, 3.1 RV6350D, 2.6 RV
Capillary Rheology, performed at 230oC 4.0 Materials of Construction All metal parts in the extrusion process should be constructed of stainless steel to minimize corrosion. Furthermore, PLA should not be left in the extruder, polymer filter, polymer transfer lines, spin beam, spinnerets or any other part of the extrusion system at PLA melt temperatures or higher for extended periods. Below is a guideline for the recommended types of steel that should be used in the extrusion system.
Part Steel Type Melt pumps and bearings SUS440B Pump blocks SUS631 Transfer lines and spin beam SUS440C
5.0 Drying PLA resin can be successfully dried using most standard drying systems. Recommended conditions are provided for standard desiccant based column dryers. For other drying system designs, additional information can be provided upon request. To prevent equipment corrosion, it is not recommended to dry or store hot PLA resin in carbon steel vessels (see Section 2.0).
In-line drying is essential for PLA resins. A moisture content of less than (50 PPM) is recommended to prevent viscosity degradation. Material is supplied in foil-lined containers dried to less than 400 PPM as
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measured by NatureWorks LLC internal method. The resin should not be exposed to atmospheric conditions after drying. Keep the package sealed until ready to use and promptly dry and reseal any unused material. The drying table below can be used to estimate the drying time needed for PLA. Air or nitrogen based desiccant drying systems can be used at the recommended temperatures. Typical PLA drying conditions are shown in the table below.
Typical Settings Drying Parameter Amorphous
(6301D, 6350D-Pellets that are clear)
Crystalline (6201D, 6251D, 6400D-Pellets
that are opaque) Residence Time (hours) 4 2
Air Temperature (oC) 50 100 Air Dew Point (oC) - 40 - 40
Air Flow Rate (m3/min/kg resin) > 0.031 > 0.031
Typical PLA Raw Material Drying Conditions Typical desiccant dryer regeneration temperatures exceed the melt point of PLA resins. To prevent issues with pellet bridging, sticking or melting, the drying system should be verified to ensure temperature control is adequate during operation as well as during regeneration cycles since valve leakage is common in many systems. 6.0 Melt Spinning
Prior to introducing PLA into any melt spinning system, the system should be properly purged to prevent any polymer contamination and spinnability problems from occurring. The purging procedures below are recommended for optimal removal of other polymers.
6.1 PLA Purging Procedure Following PP in your systems (not degraded by cooling and re-heating system)1. At normal PLA operating temperatures, run a high melt index PP (15- 40 MI) without spinneret in place.
Purge for at least 3x average residence time. Let system empty as much as possible. 2. Transition to purge PLA and purge following the same guidelines as step 1. 3. Insert pre-heated spinneret and allow temperature to equilibrate.
Purge with PLA grade to be used in extruder and evaluate flow from capillaries. As long as flow is even from each capillary and there is no evidence of contamination, begin spinning.
4. Purge all PLA from the extrusion system, using a high melt index PP, immediately after completion of the production run
Following PET, Nylon, or HDPE in your systems1. Purge with low MI (<1) PP at normal PET operating temperatures. Purge for at least 3x average residence
time (~30 minutes). Let system empty as much as possible. 2. Change to normal PLA operating temperatures and run a high melt index PP (15- 40 MI).
Purge for at least 3x average residence time. Let system empty as much as possible. 3. Transition to purge PLA and purge following the same guidelines as steps 1 and 2. 4. Insert pre-heated spinneret and allow temperature to equilibrate. 5. Purge with PLA grade to be used in extruder and evaluate flow from capillaries. As long as flow is even
from each capillary and there is no evidence of contamination, begin spinning. 6. Purge all PLA from the extrusion system, using a high melt index PP, immediately after completion of the
production run Important Notes: 1. It is critical that all drying and conveying/receiving systems be free of all PET or PP and is vacuumed to
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ensure that there is no remaining polymer dust, before adding PLA. PET will not melt at PLA operating temperatures and will block screens, if it is present in the system.
2. Brand of PP used for purging is unimportant, as long as it does not thermally cross-link. 3. It is important to purge all extruders being used shortly before running, preferably at the same time, just
prior to spinning. Extruders that are left at temperature with any PLA can lead to degraded polymer that will cause problems in filtration/spinning.
4. When handling PLA pellets, the generation of small particles or fines is possible. Conveying pellets slower, such as at a velocity of 25 m/s, will generate fewer fines than at 30 m/s when conveying in dilute phase. Please note that with dilute phase conveying, enough velocity must be maintained to prevent the pellets from plugging the line. Internal and external testing did not show plugging problems at 25 m/s.
6.2 Extrusion
A general-purpose single-screw extruder, 24 to 36:1 L/D with feed-throat cooling is acceptable for processing PLA. Effective feed-throat cooling is important to prevent the formation of a melt-block with amorphous gradess. A mixing tip is generally recommended along with static mixers in the product line to ensure temperature uniformity as well as optimum additive dispersion and melt polymer homogeneity. The following table shows a typical melt profile for PLA.
Extrusion Area Melt Temperature Setting
(oC) High Melting PLA Components
Melt Temperature Setting (oC) Low Melting PLA
Components Feed throat 25 25
Zone 1 200 200 Zone 2 220 200 Zone 3 230 170
Melt pump 240 240 Spin head 240 240
Typical PLA Extrusion Conditions
Note 1: Temperatures are only starting points and may need to be altered. Target PLA melt temperatures (after melt pump) should be in the range of 225-245°C (437-473oF). Note 2: PLA resins should not be processed at temperatures above 250°C (482°F) due to excessive thermal degradation. 6.3 Additives Delusterants such as TiO2 are best added as a masterbatch at 15-30 wt% in PLA resins and controlled dosing the required amount of dried masterbatch into the feed throat of the running extruder. 6.4 Filtration PLA resin will be provided pre-filtered to a level of 20 microns. The following pack makeup is recommended: Loose media (optional - depending upon pack configuration) 200-350 micron shattered metal is recommended for an uncompressed pack cavity fill. Screens – cascade configuration with appropriate support screens is recommended with finest filtration level of 325 mesh.
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6.5 Heating Systems
To allow for the required temperatures to be obtained in spinning, typically vapor heat transfer system medium changes are required. Dowtherm® J / Therminol® LT or a comparable vapor HTM which has an atmospheric boiling point of 200°C or less while remaining within specific system pressure design limits is generally recommended. Operation of the HTM system at a temperature as close as possible to the actual melt temperature (235±5°C) is recommended to provide an adiabatic spinning system. For vacuum assisted systems, typically heat transfer medium changes are not required as long as the system vacuum can be operated at a level to provide vaporization and uniform heating at the suggested temperatures (230-240°C). Prior to being placed into service, spin packs should be heated to 250oC to allow for some temperature loss during spin pack installation. 6.6 Spinnerets Recommended capillary dimensions for a fiber with a solid round cross section range from 0.2-0.35 mm diameter, typically with a 2 to 3:1 L/D ratio. Larger capillaries may be necessary for fiber’s greater than 6 dpf. The following guide can be used to estimate spinneret requirements based on spun product dpf:
Spinneret Capillary Sizing
0.15
0.2
0.25
0.3
0.35
0.4
0 2 4 6 8 10
spun dpf
diam
eter
mm
2 L/D3 L/D
Capillary dimensions for modified cross sections will deviate greatly from solid round fibers. They should be designed to meet the desired fiber shape, while providing adequate pressure drop to ensure good denier uniformity and adequate draw down or stretch ratio to facilitate good spinning performance. Pack designs for production of bicomponent fibers vary greatly with type of fiber, equipment manufacturer and polymers intended to be process. Spinneret or extrusion system manufacturer should be consulted to ensure appropriate configuration is used. Improper pack set-up can lead to high pressure and pack leaks and should be avoided. 6.7 Quenching Filaments should be quenched with air at controlled temperatures and velocities to ensure good denier and orientation uniformity. Typical quenching conditions are shown below, but quenching conditions need to be optimized by product depending upon the denier, spinneret design, and cross section. In some cases, special quenching conditions need to be used to avoid fibers sticking when condensing them, or to create some special effects in the fibers.
Quench parameter Typical Target Quench Air velocity (m/s) 0.26 – 1.5
Quench Air Temperature (oC) 10 – 20 Monomer Exhaust Velocity (m/s) .26 – 2.0
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Spacer or Shroud Length (mm) 50 –100
Typical PLA Quenching Conditions A monomer exhaust system is preferred to prevent the buildup of residual lactide around the spinneret face and quench screen. 6.8 Take Up PLA can be spun over a wide range of take up speeds, but typically runs between 1100 and 1850 m/min. Low or high viscosity components in bicomponent fibers can further limit the maximum take-up speed.
7.0 Drawing
A modern polyester type draw line equipped with accurate speed, temperature and tension controls is recommended for drawing PLA. Two-stage drawing is preferred to maximize tensile properties without stress whitening PLA. Fleissner and Neumag manufacture suitable draw lines for PLA. An illustration of a typical line is shown below: When running on older lines, draw ratios that can be achieved will depend on the degree of control over temperatures, both water and steam, the type of draw roll heating employed, the length of water baths and steam chests and the line speed. In short, uniform drawing depends on heat transfer rates from the equipment to the fibre and the degree of control over drawing temperatures and conditions. Several factors impact the heat transfer rate, including:
Tow mass Initial tow temperature. Line speed Contact area of the rolls (diameter) and layout Number of rolls Method of heat application (immersion bath, sparge systems)
Note, with bicomponent fibers, draw temperatures applied, especially by draw rolls, is limited by any low-melting components. This can lead to limited draw ratios and limited ability to heat set fibers. Also, draw ratios can be limited by higher viscosity components in the bicomponent fiber. Draw ratios should be maximized to optimize tensile properties, without severe crazing (stress-whitening). Temperatures applied in drawing should be as high as possible to allow drawing without sticking on rolls and equipment. 7.1 Creeling and pre-tensioning 7.1.1 Creel Size Creel size is largely dependent upon the crimper size and the tension rating of the drawstands. PLA can be run at similar tow densities in crimping as PET, with typical densities ranging from 65 to 72 thousand dtex per cm of crimper width. Through experimentation, this can be optimised, along with crimp properties 7.1.2 Creel Tensioning Creels should be designed to provide a minimal tension level on each subtow in the creel. If the tension is too great, typically greater than 0.2 g/den, the tow could begin drawing before or during immersion in the pre draw bath, causing excessive denier variation along with the possibility of broken fibers and high wrap rates. In addition, the tension level between individual subtows in the creel should be uniform. An
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adjustable pre tension stand is preferred prior to the pre draw bath to assist in equalising the tension between subtows. 7.2 Pre Draw Bath Pre-draw baths should be sufficiently long to enable saturation of the tow with moisture and finish and to initially raise the tow temperature to 25-50oC. The tow should not be heated above PLA’s Tg (58oC), other wise the tow could begin drawing, which would lead to the same types of problems described in the preceding section. Also nip rolls are recommended on the pre draw rolls to minimize tension on the towband before drawing. 7.3 Drawing 7.3.1 Temperatures The drawing occurs in the one draw stage, where the tow temperature should be maintained between 45 and 70oC. Roll cooling is recommended on the post draw stand to prevent the tow band from sticking to the rolls. To achieve the recommended tow temperatures, heating systems between the draw roll stands are required. Poor distribution of heat will lead to poor tow temperature uniformity, resulting in non uniform drawing and potentially broken fiber and/or undrawns. Immersion baths also provide good tension and drawing uniformity, provided that they have good temperature control and adequate circulation capabilities. 7.3.2 Draw Ratios PLA can be drawn over a wide range of draw ratios. The optimal draw ratio is dependent upon the type of polymer used, the type of bicomponent configuration used, the as spun orientation level, and the desired tensile properties for the product. PLA staple fiber is typically drawn in the 3:1 – 4:1 range. As mentioned earlier, two-stage drawing is recommended due to potential stress whitening concerns with single stage drawing. If stage 1 draw ratio is too high, the fiber will stress whiten, or craze. The % of the total draw ratio is typically split 70/30 between stage 1 and 2, but will require optimization by process and manufacturing line. 7.4 Finish application Finish should be applied before entering the dryer or heat setter. Applying finish after the dryer will de-stabilize the tensile properties of the fiber with time. Finish should be selected based on planned downstream processing. Goulston Technologies, Inc or Takemoto Oil and Fat Company LTD can recommend and provide finishes for PLA that have been proven for a variety of applications. Depending on subsequent processing and finish types, application levels range from 0.35% up to 0.8% finish on fiber. 7.5 Crimping 7.5.1 Lamination, and Presentation Tow density, lamination and presentation upon entry into the crimper are critical to providing uniform crimp across the width of the tow band. Tow stackers and/or ply bars are recommended for achieving uniform tow density across the tow band. Dancer rolls are also recommended to maintain a constant tension on the tow entering the crimper. 7.5.2 Heating systems
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Heating capabilities, preferably steam, are recommended prior to and during the crimper process. Pre heating the tow before entering the crimper allows the fiber to bend easily with minimal mechanical pressure. Heating the fiber during crimping provides greater crimp permanency. Typical tow temperatures before and during crimping are shown in the table below. These temperatures may need to be optimized for each process.
Typical Temperatures Process location oF oC
Entering Crimper 70-90 21 - 32 In the Crimper 70-90 21 - 32
Typical Tow Temperatures in crimping
7.5.3 Crimping Minimal mechanical pressure should be used to crimp PLA to decrease the potential of fiber damage. The primary process variable for increasing crimp level should be the tow temperature entering the crimper. The flapper pressure should be used as a secondary control parameter to increase crimp level. Typical flapper and roll pressures for a bicomponent containing a low melting PLA component along with processes are shown below. Flapper and roll pressures will need to be adjusted for each process to achieve desired crimp levels.
Product denier Typical flapper pressure (bar) Typical roll pressure (bar) 4 (PLA/PET bico) 1.0 – 2.0 1.5 – 2.5
Typical mechanical pressures in crimping
7.6 Heatsetting Hot through air dryers are recommended for drying and heatsetting. The dryers should have multiple zones with a cooling zone at the dryer exit. Temperature control is critical, as the objective is to expose the fiber to temperatures as close to the melt point as possible without actually melting the fiber. Recommended drying temperatures for PLA range from 120 to 140oC for high melting fibers only. If bicomponent low-melting components are included, care must be taken at any temperature above the Tg of 55oC-57oC, to avoid blocking or melting of the low melting component. Depending on %D level of the PLA used, the temperature at which the fiber will melt and flow will vary from about 100oC to about 150oC. An experimental approach to determine the optimum heat setting dryer should be taken, to determine the maximum temperature that can be used without causing the fiber to block in processing or bale storage. 7.7 Cutting The temperature of the tow should be maintained below 50oC to ensure that the crimp does not get pulled out due to the tension at cutting. Tension stands are recommended prior to cutting. Conventional rotary cutters are acceptable. 7.8 Baling Conventional polyester balers are acceptable for baling PLA. The bale density required to produce stable bales will vary with denier and finish type. Bale densities range from 0.27 – 0.40 g/cm3 (17 – 25 lb/ft3). Typical pressures applied in baling range from 50 to 100 psi. Low melt point binder fibers require lower ram pressure to minimize the potential of fiber sticking together in the bale. For low-melt fibers, pressures of 50 psi or less are recommended.
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7.9 Fiber Storage Baled fiber should be stored in cool, clean, dry location to prevent hydrolysis and contamination. Environmental conditions of 25oC, 55% RH are recommended. 8.0 Fiber Properties The table below shows some typical PLA fiber properties.
Fiber Property 4 dpf bicomponent PLA low Melt Sheath, PET Core
Denier 3.75-4.5 CPI 5-7 Tenacity (g/den) >2.5 Elongation to break (%) 70-110 Finish on Fiber (%) 0.25-0.35 Hot air shrinkage (130oC, 10 mins) < 15%*
* Note: Air temperature of 110C for 10 minutes 9.0 Attachments 9.1 Investigation of Bondability through bicomponent fibers with various D levels 9.2 Investigation of Shrinkage vs. Composition in Air Drawn Fibers 9.3 Fiber Properties in Crimping Experiment 9.4 Investigation of Spinning Speeds of Various Bicomponent Fibers 9.5 BCF and Bicomponent Trials 9.6 BCF and Bicomponent Follow-Up Trials 9.7 Comparison of Bicomponent Properties 9.8 Typical Staple Fiber Spinning System6
9.9 Typical PET Drawline Recommended for PLA Bicomponent Processing5
1 NatureWorks is a registered trademark of NatureWorks LLC
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9.1 Investigation of Bondability through bicomponent fibers with various D levels NB96004 Date: January 24, 1996 From: Nancy Buehler Subject: Results from Fiber Experiment EXPERIMENT: FIX60100 OBJECTIVE:
The aim of this experiment was to determine the crystalline melting temperature and thermal bondability ("tack") temperature of oriented PLA fibers at different D levels. BACKGROUND:
It is useful to understand how D level influences the crystalline melting temperature and thermal bondability characteristics of PLA fibers. As stated in the experimental outline, the desirable attributes of bicomponent fibers is to (1.) have high heat resistance and (2.) low thermal bonding temperatures. The data generated from this experiment will be used to select grades of PLA to be screened in bicomponent fibers. MEASURES OF SUCCESS AGAINST STATED OBJECTIVES:
Crystalline melt temperatures vs D level of as spun fibers Crystalline melting temperatures vs D level oriented 3:1 at 70C Crystalline melting temperatures vs D level after annealing at 100C, 120C and 140C, for 48 hours A plot of the Peak Melting Temperature vs Annealing Temperature to give equilibrium Tm vs D
level MATERIALS: LOT # MN MW PDI LACTIDE TOTAL % D389-2 95,500 218,000 2.28 1.62 3 386-1 98,900 226,000 2.28 0.77 6.3 372-3 95,400 203,000 2.13 0.31 8.5 416-2 99,000 230,000 2.30 1.32 11.8 418-2 90,800 210,000 2.30 0.86 15.3 423-3 92,000 234,000 2.55 1.02 17.8 STEREOCHEMISTRY IDENTIFICATION LOT# L-MER D-MER L-LACTIDE D-LACTIDE MESO LACTIDE389-2 97.0 3.0 96.80 2.80 0.40 386-1 95.7 6.3 93.56 5.57 0.87 372-3 91.5 8.5 91.40 8.10 0.80 416-2 89.7 10.3 87.09 7.69 5.22 418-2 85.90 14.1 82.13 10.32 7.55 423-3 83.80 16.2 79.05 11.47 9.48 EXPLANATIONS OF DEVIATIONS FROM EXPERIMENTAL PLAN:
Currently, there is no ASTM or industry standard method for determining "tack" temperature. "Tack" temperatures will not be reported here.
DMA has a long lead time and samples are not long enough to fit in the grips of the fixtures
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Unable to get the "as spun" fibers down to 30 microns "As spun" fibers were oriented 3:1 at 70C, because fibers undergoing higher orientations at
these temperatures spanned KEY LEARNINGS:
Plotting the melting temperature by the Lot #, there is an apparent increase in melting temperature with decreasing meso and D content in the polymer.
There is no statistical difference in melting temperatures among quiescent samples annealed at 100C, 120C and 140C.
No evidence to support differences in the glass transition temperatures for quiescent samples annealed at 100C, 120C and 140C.
Statistically, this experiment has shown that the mean glass transition temperature for oriented fiber is almost 10C higher than the as spun fibers
Likewise, the onset of the glass transition is higher for the oriented fibers than for the as spun fibers
The onset of the crystallization exotherm is lower in oriented fiber samples The as spun fibers have a higher crystallization exotherm peak than oriented samples There appears to be no apparent difference in peak melting temperatures between as spun and
oriented fibers TABLE 1. As Spun Fibers from Rheometer Lot # Tg onset Tg midpt Tc onset Tc peak Tm onset Tm peak Cryst. (C) (C) (C) (C) (C) (C) (J/g)389-2 48.23 52.85 81.43 96.62 151.79 163.64 3.96 386-1 51.22 54.53 101.42 120.2 138.39 148.83 1.31 372-3 50.79 53.58 102.26 119.13 133.42 139.04 0 416-2 50.53 52.88 418-2 49.62 51.29 423-3 50.27 51.94 TABLE 2. Oriented Fibers: 3:1 at 70C Lot # Tg onset Tg midpt Tc onset Tc peak Tm onset Tm peak Cryst. (C) (C) (C) (C) (C) (C) (J/g) 389-2 62.9 66 71.37 77.76 147.61 161.05 27.77 62.90 65.90 70.96 76.93 144.88 160.40 27.05 386-1 62.73 65.95 76.36 89.44 137.10 148.55 16.4 61.15 64.28 75.47 89.32 132.59 147.38 10.3
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372-3 61 64.65 80.08 100.4 127.6 137.76 10.92 59.9 60.80 89.20 108.44 129.19 137.05 4.62 416-2 58.7 60.88 103.73 120.17 2.53 57.98 59.61 105.45 120.15 1.61 418-2 54.97 57.89 52.28 54.53 423-3 53.85 57.28 50.96 55.18 TABLE 3. Annealed pellets: 100C for 48 hours Lot # Tg onset Tg midpt Tc onset Tc peak Tm onset Tm peak Cryst. (C) (C) (C) (C) (C) (C) (J/g)389-2 57.6 62 149 164.57 40.68 386-1 51.19 54.87 138.62 150.27 38.75 372-3 56.92 60.74 127.99 143.7 27.03 416-2 53.76 56.88 109.14 124.5 13.29 418-2 56.42 58.22 423-3 56.32 57.92 TABLE 4. Annealed pellets: 120C for 48 hours Lot # Tg onset Tg midpt Tc onset Tc peak Tm onset Tm peak Cryst. (C) (C) (C) (C) (C) (C) (J/g)389-2 54.9 60.02 153.76 170.53 46.59 386-1 54.43 57.99 142.27 158.07 39.91 372-3 53.02 56.44 132.15 147.85 26.3 416-2 55.09 59.82 418-2 52.04 55.71 423-3 54.87 57.1
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TABLE 5. Annealed pellets: 140C for 48 hours Lot # Tg onset Tg midpt Tc onset Tc peak Tm onset Tm peak Cryst. (C) (C) (C) (C) (C) (C) (J/g)389-2 54.89 59.39 161.23 179.47 50.47 386-1* 51.72 55.8 97.17 115.05 132.63 144.97 20.1 159.17 169.92 372-3 57.75 60.6 416-2 56.69 59.05 418-2 52.62 56.14 423-3 53.93 57.19
A sample from Lot 3861 annealed at 140C for 48 hours displayed two melting endotherm peak. The onset temperature of the first endotherm is 132.63C with a peak temperature at 144.97C and a second endotherm onset at 159.17C and peak melting temperature at 169.92C. This trend is reproducible, see Lot 3861, annealed 140C duplicate. TABLE 6. Peak Width of Melting Endotherm As Spun Oriented Annealed Annealed Annealed Peak Width Peak Width 100C 120C 140C Lot # (C) (C) Peak Width Peak Width Peak Width389-2 12.14 14.29 16.09 15.41 16.96 386-1 11.51 11.83 12.75 15 11.34 372-3 7.97 11.91 15.35 15.39 0 416-2 0 15.6 16.74 0 0 418-2 0 0 0 0 0 423-3 0 0 0 0 0
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9.2 Investigation of Shrinkage vs. Composition in Air Drawn Fibers NB96005 NAF-649480 PART 1. The Relative Thermal Shrinkages of PET and PLA Filaments Location: Hills, Incorporated Key Contact: Jerry Taylor 7785 Ellis Road Arthur Tally West Melbourne, FL 32904 PH: (407) 724-2370 FAX: (407) 676-7635 Objective:
Compare the relative shrinkages of PET and PLA as spun filaments spun at 1.0 g/min/hole with varying draw force. Key Observations:
1. Higher filament velocities reduce boil shrinkage for PET and PLA filaments. (Figures 1. and Figure 2.)
2. At moderate throughputs,1.0 g/min/hole, the critical filament velocity is slightly higher for PET filaments, Figure 1. (Critical filament velocity defined as the velocity at which filament shrinkage is reduced to 10% or below).
3. There appears to be an increase in boil shrinkage for PET filaments spun at speeds above 5300 m/mint A similar trend has been observed in PLA filaments produced at Alex James and Associates. (Figure 1.)
4. Critical filament velocity for PLA filaments is calculated to be 4526 m/min for the processing conditions disclosed. (Figure 2.) 5. Critical filament velocity for PET is 5314 m/min at comparable processing conditions. (Figure 1.)
6. PLA yields lower birefringence values at all filament velocities suggesting lower degrees of crystal and amorphous orientation. (Table 1.)
Unexpected Occurrences:
1. Due to complications with the confidentiality agreement resulting in a one way nonanalysis agreement with Ason. Cargill, Inc. was not allowed to observe Ason technology or other filament processing using Hill's slot die.
Procedure:
1. Air attenuated slot die located approximately 34 " from spinneret 2. 2 extruders, melt pumps and 144 hole pack purged with PP-35 MFR and then purged with PLA Lot 515-710. 3 Polymer was packaged in 10 lb bags and put into hoppers with nitrogen sparge. 4. Melt temperature set at 230C for both extruders. 5. Spinnability performance evaluated by Ason representatives; rating system: qualitative good or poor
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Equipment:1. Pilot spinline utilizing (2) 1.25" single screw extruders 2. Slot die with air quench (designed and manufactured by Hill, Inc.) 3. Melt pumps (2): 6 cc/rev 4. Pack: 1 X 144 capillary with 0.35 mm diameter, 4:1 I/d 5. Air quench used
Trial Outline: Throughputs: 1.0 g/min/hol Air Draw Pressures: 10-60 psi PLA with 10 psi increments 10-80 psi PET with 10 psi increments Distance from Spinneret: 20" for PLA (Location of Draw Unit)34" for PET Process Data: Collected and recorded by Hills, Inc. Refer to Development Log Sheets 1 & 2 Fiber Data: GPC DSC Filament boil shrinkage Birefringence Fiber diameter Calculated Filament Velocities Polymer Evaluated: Lot/Box Mn Mw PDI % R % Lactide % Olig.515-710 69,400 146,000 2.1 1.2 0.4 0.1 Discussion:
The objectives outlined for the scheduled December 913 trial at Hills, Incorporated were to (1) prepare a low shrinkage web using Ason technology and (2) make bicomponent (PP/PLA) filaments to characterize crimp and loft properties. There were some modifications made to the run plan because of complications with the confidentiality agreement with Ason/Hills. It was negotiated that a one way nonanalysis agreement be put into place. Filament Velocity and its Impact on Shrinkage:
It appears, from process information shared by Ason, that the critical filament velocity for PET is slightly higher than for PLA filaments run under similar conditions, (refer to Table 1). Both cases ran comparable throughputs of 1.0 g/min/hol. Spin ratings were not measured using the S.Gessner 18 system. Birefringence values were indicative of low spinline stress during spinning (refer to Table 1). And higher filament velocities were required to increase spinline stress to achieve low shrinkage filaments, those with less than 15%.
Polymer variables as well as processing parameters may be responsible for this trend. Molecular weight of Lot 515-710 was slightly lower than previously run at Alex James, Inc. GPC analyses performed on these filaments ranged from number average molecular weights of 63,000 to 66,000 and weight averages between 133,000 and 136,000. The lowest weight average run prior to this trial was approximately 155,000. Lower molecular weights may be partially responsible for reduced spinline stress compounded
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with melt temperature effects. Residual lactide and oligomer values were both less than 0.5%; low enough not to influence melt flow character of the resin.
As far as processing parameters are concerned, melt temperature was set at 230C, about 10 degrees
cooler than previously run at other trials. Cooler melt temperatures would imply highly spinline stress. Throughputs were about 20% higher than normally run and more likely the reason for the shift to higher filament velocities.
In addition to higher throughputs, the distance between the drawing unit and spinneret may also be
responsible for low spinline stress. Generally, the stick point is a good indicator of how cool/hot filaments are before they are drawn. A stick point closer to the slot die will draw the filaments while they are still molten generating a lower degree of spinline stress affecting the overall degree of orientation and stressinduced crystallization.
Although, utilizing Ason's technology with its adjustable draw unit may provide a process to control the amount and degree of orientation intoduced to the system, whether controlling spinline stress is advantageous or not is still in question. PLA filaments with low degrees of shrinkage have been made on conventional lines reducing the need for Ason technology to make bonded fabric with superior performance properties.
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9.3 Fiber Properties in Crimping Experiment
Table 1: Fiber Properties (Lot 440-719)
Sample Tenacity % Break Fiber Modulus Crystallinityg/denier Elongation g/denier jg-1
320 dpf input multifil 1.54 72 24.6medium crimp 2 28 16.4 37air entangled 1.74 29 18.7self crimped 2.07 25 19 30
Figure 1: TechniService Texturizing (crimping) Process
Stuffer boxCrimper
Creel with 8bobbins
Winders
Heated Draw 90CRolls 75C
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9.4 Investigation of Spinning Speeds of Various Bicomponent Fibers Trial Number: NWB12097BC Trial Description: Relative Spinning Speeds of Sheath-Core and Side-by-Side Bicomponents Containing PP/PP, PET/PP and PLA/PP. Trial Reference Number: TR-510D Location: Key Contact:Hills, Incorporated Jerry Taylor 7785 Ellis Road Phone: (407) 724-2370 West Melbourne, FL 32904 Fax: (407) 676-7635 Overview: The objectives of this trial were to compare the relative spinning behavior among PP/PP, PET/PP and PLA/PP sheath-core and side-by-side bicomponents and determine whether PLA/PP bicomponents offer any commercially valuable processing or property advantages to conventionally used materials. Trial results do in fact suggest that there are both processing and property advantages to using PLA with PP configured side-by-side, 50/50. The configuration mentioned above had the fastest calculated filament velocities over a large range of air draw forces and later these filaments proved to have more induced crimp behavior than PET/PP configured the same way. Objective(s): 1. Define the quench limitations of PP/PP, PLA/PP and PET/PP sheath-core bicomponents 2. Measure the relative speeds of spinning for sheath-core and side-by-side PP/PP, PET/PP and PLA/PP bicomponents. 3. Determine the relative crimp behavior of PET/PP and PLA/PP side-by-sides. Results: It appears that there is an inverse relationship among: Measured filament diameter, calculated filament velocity and applied air draw force variables for the side-by-side bicomponents. PLA/PP in a 50/50 weight ratio showed the most pronounced response to increasing air draw force. The results of this effect are illustrated in Graphs 1. and 2.
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Graph 2. For sheath-core configurations, fiber diameter did decrease with increasing air draw force as expected, however, it was without the same level of resolution as observed with the samples configured side-by side. PP/PP, PET/PP and PLA/PP in sheath-core configurations had similar filament velocities for a given air gun pressure. It is speculated that for sheath-core configurations, the PP core controls the quench rate of the filaments, ultimately controlling the final filament velocity. The rate at which different materials quench in the spin-line determines their relative spinning behavior. Under similar spinning conditions, relative spinning behavior may be represented by the
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stick point. Stick point is the measured distance in the spin-line, in inches, from the spinneret to where filaments stick to a stainless steel rod. These measurements demonstrate that the spinning behavior of polypropylene can be dramatically improved under critical quench conditions by adding a sheath of PLA. PET on the sheath offers the same processing advantages as PLA under moderate spinning conditions. However, PET/PP is limited at low throughputs, and/or at high air draw forces due to filament breaks. It is thought that the fast quenching behavior of PET cools the filaments close to the spinneret decreasing the elasticity of the spin-line. Table 1. below displays the stick points for PP/PP, PLA/PP and PET/PP at three different quench conditions. From the table, it appears that sticking is the critical issue for monocomponent PP. Sticking can occur at higher throughputs or at insufficient air draw forces. PET/PP, on the other hand is ultra sensitive to quenching conditions and frequently breaks are experienced at lower throughputs or high air gun pressures. PLA/PP seems to be less sensitive to either of these extremes. Less sensitivity to quenching conditions may provide processing advantages to conventional materials used today. Less sensitivity may mean faster speeds of spinning which may lead to higher production rates overall. Table 1. Spinning Behavior Measured as Stick Point for 50/50 Sheath-Core Bicomponents
Throughput (g/min/hole)
High Quench Medium Quench Low Quench
PP/PP PLA/PP
PET/PP
PP/PP PLA/PP
PET/PP
PP/PP PLA/PP PET/PP
0.1 breaks breaks breaks breaks breaks breaks breaks 2 breaks0.2 breaks 3 breaks 7 4 breaks 21 4 breaks
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0.3 5 3 breaks 11 5 breaks sticking 5 breaks0.4 7 6 breaks 13 6 breaks sticking 7 breaks0.5 9 6 breaks 13 7 breaks sticking 8 breaks0.6 11 7 breaks 20 7 7 sticking 10 6 0.7 12 8 3 sticking 6 7 sticking 10 7 0.8 13 9 5 sticking 10 8 sticking 12 8 0.9 14 9 6 sticking 13 8 sticking 13 8 1 17 9 6 sticking 13 9 sticking 17 9
1.1 17 10 7 sticking 15 9 sticking 17 11 1.2 17 12 7 sticking 18 10 sticking 20 11
Self-crimp is a behavior that is often observed with natural fibers, like cotton. However, this property can also be achieved with thermoplastics when there is a viscosity differential between the two polymers being used. Traditionally, PET has been used in combination with PP to achieve this type of behavior. Because PLA has greater shrinkage potential and shrinkage tension at lower temperatures, replacing PET with PLA would require less polymer to achieve the same crimping behavior. Or if an equivalent quantity of PLA were used, improved crimp would be possible. Shrinkage tension measurements are not complete yet, but Tables 2. and 3. below report crimp frequency for PLA/PP and PET/PP S/S at 50/50 and 30/70 weight basis ratios. Table 2. Crimp Frequency (# crimps/inch) for PLA/PP and PET/PP Side-by-Side Bicomponents at 50/50
23C
50C
100C Temperature: Polymer PET/PP PLA/PP PET/PP PLA/PP PET/PP PLA/PPThroughput(g/min/capillary)
(crimp/in.) (crimp/in.) (crimp/in.) (crimp/in.) (crimp/in.) (crimp/in.)
0.3 2.7 9.6 6.3 20.7 108.7 105.8 0.4 3.8 7 7.2 14.1 35.3 52.2 0.5 4.8 7.8 9.5 9.3 38.8 56.4 0.6 4.9 5 5.4 18.5 42.3 43.7 0.7 5.3 6.4 4.9 12 38.8 55
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0.8 4.4 2.2 5.8 11.8 49.4 46.6 0.9 4.7 6.1 6.2 4.3 63.5 40.1 1 2.1 5.8 3.6 10.6 49.4 44.5
1.1 4.2 4.7 5.7 9 39.5 26.1 1.2 3.2 5.2 9.3 45.2 57.2
Table 3. Crimp Frequency (# crimps/inch) for PLA/PP and PET/PP Side-by-Side Bicomponents at 30/70
23C
50C
100C Temperature: Polymer PET/PP PLA/PP PET/PP PLA/PP PET/PP PLA/PPThroughput(g/min/capillary)
(crimp/in.) (crimp/in.) (crimp/in.) (crimp/in.) (crimp/in.) (crimp/in.)
0.3 7.9 12.7 19.1 26.5 35.3 44.5 0.4 1.9 8.6 12.1 24 35.3 45.2 0.5 5.8 9.1 13.5 29.8 38.8 35.3 0.6 4.4 6.8 9.9 24 38.8 36.8 0.7 9.7 6.3 10.4 25.4 22.6 52.2 0.8 5.3 6.4 8.5 14.4 45.9 48.7 0.9 5.4 7.4 8.4 19.4 30.3 36.8
Materials:
PLALot/Box Mn Mw PDI % lactide % R 515-710 69,000 146,000 2.1 0.4 1.2
PP
Montell polypropylene 35 MFI
Discussion: Fiber structure development and property characteristics are strongly influenced by the thermal stress histories experienced by the polymer in the spin-line. Although two polymers are extruded at the exact melt temperature, as is the case when making bicomponent fibers, these materials can have substantially different thermal stress histories. Depending on these thermal histories and mutual interactions, the possibility of improving or controlling the structure and properties of high-speed spun bicomponents exists. High-speed spinning really addresses the rate at which the filaments can be drawn. Breaks or sticking during spinning are considered processing limitations. In the sheath-core configuration, PET/PP filaments are extrememly sensitive to low throughputs and
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high air pressures. PP/PP on the other hand, does not quench as quickly and therefore sticks and ropes at higher throughputs and/or low air gun pressures. It seems that PLA/PP filaments do not quench nearly as fast as PET/PP and therefore do not break at lower throughputs and high air draw forces. However, PLA/PP sheath-core bicomponents quench relatively fast when compared to PP. PLA/PP sheath-core bicomponents can be spun at a wider range of processing conditions where PET/PP and PP/PP have limitations. High-speed spinning for side-by-side bicomponents have a complexity of issues different from sheath-core filaments. The spinning behavior of the side-by-sides filaments cannot be captured by stick point as was done for the sheath-core filaments. Two polymer extruded at one melt temperature experience different quench rates. Both surfaces are exposed which make it difficult to determine a "true" stick point. Holding air pressure constant, and increasing the throughput, PET/PP and PP/PP both displayed roping behavior. At 100 psi gun pressure and a throughput of 1.2 g/min/capillary, evidence of roping was observed for the PET/PP bicomponents. At the same throughput and 50 psi, serious sticking was observed. On the otherhand, PLA/PP was not nearly as sensitive to roping or sticking. It is believed that roping and sticking exists in the PET/PP side-by-sides because PP is being extruded at 295C. Typically, it is extruded at 230C or so. Because it is more than a 100 degrees above its true melting point, about 170 degrees or so, it increases the time required to quench the material. Between the PLA/PP and PP/PP bicomponents, it was difficult to determine a big difference in spinning behavior for side-by-sides. This was not the case in the sheath-core configurations. Filament diameters for PLA/PP side-by-sides revealed substantially higher calculated filament velocities. Not only did the 50/50 PLA/PP side-by-sides spin faster than any of the other combinations used, they also achieved more crimp than their as spun PET/PP counterparts. This trend was not observed in the 30/70 PLA/PP side-by-sides. It is postulated that as PP becomes more of the continuous phase spinning behavior and properties will most likely be representative of PP. Trial Outline: Part 1. Samples were collect for S/C bicomponents at increasing throughputs and constant pressure, 80 psi, for three different quench conditions. Stick point was the measured response variable for each of the combinations listed below. 50/50 30/70 PP/PP PP/PP PLA/PP PLA/PP PET/PP PET/PP
Throughput
(g/min/capillary) High Quench (4" at 44F)
Medium Quench (2" at 44F)
Low Quench (1" at 44F)
0.1 0.2
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0.3 0.4 0.5 0.6 0.7 0.8 0.9*
1 1.1 1.2
*Due to meter pump limitations, maximum throughput for the 30/70 bicomponents was 0.9 g/min/capillary
Part 2. for the S/S bicomponents, samples were collected at each of the conditions listed below. Filament diameter and crimp tests were performed on these. 50/50 30/70 PP/PP PP/PP PLA/PP PLA/PP PET/PP PET/PP
Throughput
(g/min/capillary) High Quench (4" at 44F)
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9*
1 1.1 1.2
Part 3. Throughput was held constant at 0.8 g/min/capillary, while air pressure varied from 20-110 psi. Samples were collected in 10 psi increments. Composition and configurations are listed below. Fiber diameter were collected on these samples.
Composition sheath-core side-by-side 50/50 30/70 50/50 30/70
PP/PP PLA/PP PET/PP
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Equipment/Processing: Extruders: 2 X 1 1/4" diameter screws with L/D 30:1 4 Zones, no screw cooling Drying capacity on extruder(s): Conair 110 lb capacity and Novatec with 250 lb capacity Meter pumps: 2 1X6 cc/rev Quench: One-sided with cross-flow air set up to deliver approximately 500-1000 fpm
Pack BuildPack Top: Standard Screen Sup Plate: Standard Meter V. Plate: 7696 Dist. Plate: 12605 Dist Plate: 11226 Dist Plate: 12229 Dist Plate: 12230 Spinneret: 288 Round, 0.35 mm
Polymer Sheath Core PLA
Lot 515-710 PP
Montell 35 MFR Extrusion
Temperatures (C)
zone1 187 187 zone 2 209 209 zone 3 219 219 zone 4 229 229 Melt
Pressures Extruder 750 750
Pack see above see above
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Speeds adjusted as a variable from
0.1 g/min/cap to 1.2 g/min/cap
adjusted as a variable from 0.1
g/min/cap to 1.2 g/min/cap
Meter Pump size/rpm
624.6
624.6
Extruder Amps/ (%) 660
660
9.5 BCF and Bicomponent Trials
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TRIAL: BCF trial Trial #BCF84320 By: Donavon Kirschbaum
Dates: October 19,20.21, 1998
Location: Hills Inc 7785 Ellis Road W. Melbourne, Fla
Key Contact: Donavon Kirschbaum (NatureWorks LLC)
Objective: Measure of success against stated Produce trilobal BCF 18-20 dpf at 1300 denier to be used for carpet fiber.
Approximately 200 lb of 1270/67 BCF trilobal fiber was produced.
Produce bicomponent side by side fibers consisting of the following: PLA/PLA 1.4%D/1.4%D different mw’s PLA/PLA 1.4%D/3.2%D PLA/PET 1.4%D/PET
Bicomponent samples were produced. The samples will be tested and characterized for self-crimping properties.
1) Equipment
Hills spin/draw line: bicomponent with 2-1.25 in. extruders. Spin pack: trilobal 67 holes for BCF Spin pack: 144 hole .35 mm (see figure below)
2) Materials:
PLA lot
# MF0628P104 MN 88.6k, Mw 179.4k, 1.4%D, MFI 8.1, color 29, %res. .17 GMID 112679
#M12328P103 MN 67.9 MW 137 3.2%D, MFI 30.9, %roes .14, GMID 111184
3) Explanation for deviations from the plan: none
4) Unexpected occurrences: • Drawing between draw roll 1 and 2 and drawing between draw roll 3 and 4 had a significant effect
on the max draw ratio. The only difference between the two is the distance between the draw rolls. The closer the draw rolls the higher the maximum draw ratio.
5) Key learning’s: BCF • PLA has improved drawability when drawing in water • Trilobal fibers process easily • 1% TIO2 masterbatch has a positive delustering effect. Bicomponent. • PLA of the same D level with two different molecular weights worked well for self-crimping fiber. • PLA/PET side by side had good adhesion under the microscope • PLA/Pet side by side worked for a self-crimping fiber.
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6) Overall assessment:
The drawing process needs further optimization to achieve the optimum fiber performance. However, until the fiber has been evaluated in a carper sample optimization will be put on hold.
Process conditions: Polymer 1.4% D 3.2% D PET Extrusion cond.
Zone 1 200 200 280Zone 2 210 210 290Zone 3 220 220 290Zone 4 230 230 290Spin Head 230 230 280melt temp 230 228 274pressure extruder 750 750 750pack 1250 1150 1420pump size cc/rev 6 6 6
Samples:
BCF • All BCF samples were drawn at 4.2 draw ratio. • Polymer was low %D 1.4% Reference # 15-36-2 15-36-5 15-36-9 15-36-13 15-36-17 15-36-21 15-36-25 15-36-30 15-36-33 Bicomponent • To be used for self crimp fibers
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Sample reference table Reference #
type polymer comments
15-45-2 s/s 1.4%D pla/1.4%D PLA
side by side, 1.4%DPLA high mw/1.4%D PLA low mw
15-45-5 s/s 1.4%D pla/1.4%D PLA
side by side, 1.4%DPLA high mw/1.4%D PLA low mw
15-45-9 s/s 1.4%D pla/1.4%D PLA
side by side, 1.4%DPLA high mw/1.4%D PLA low mw
15-47-2 s/s 1.4%D PLA/3.2%D
PLA
15-48-1 s/s 1.4%D/PET 4.6 draw ratio 15-48-2 s/s 1.4%D/PET 4 draw ratio 15-48-3 s/s 1.4%D/PET 3.5 draw ratio
BCF Process conditions BCF samples 15-36-2 15-36-5 15-36-9 15-36-13 15-36-17 15-36-21 15-36-25 15-36-30 15-36-33
As spun dpf 75.2 75 80 79.8 80.4 80.6 81 79 79.8
total denier 1200 1190 1278 1272 1283 1286 1293 1260 1273
denier /filament 17.9 17.8 19 19 19.1 19.2 19.3 18.8 19
No. orifices 67 67 67 67 67 67 67 67 67
Draw ratio 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2
spin finish 756A 756A 756A 756A 756A 756A 756A 756A 756A
Denier roll speed 156 156 156 156 156 156 156 156 156
denier roll temp amb. amb. amb. amb. amb. amb. amb. amb. amb.
# wraps 3 3 3 3 3 3 3 3 3
steam between denier and draw 1 yes yes yes yes yes yes yes yes yes
Draw roll 1 m/min 202 202 202 202 202 202 202 202 202
draw roll 1 temp 70 70 70 70 70 70 70 70 70
# wraps 5 5 5 5 5 5 5 5 5
steam between draw 1 and 2 yes yes yes yes yes yes yes yes yes
BCF
Draw roll 2 m/min 660 660 660 660 660 660 660 660 660
draw roll 2 temp 130 130 130 130 130 130 130 130 130
# wraps 17 17 17 17 17 17 17 17 17
Draw roll 3 m/min 670 670 670 670 670 670 670 670 670
draw roll 3 temp 80 80 80 80 80 80 80 80 80
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# wraps 10 10 10 10 10 10 10 10 10
texture jet temp 80 80 80 80 80 80 80 80 80
texture jet pressure 50 50 50 50 50 50 50 50 50
interlacer pressure 35 35 35 35 35 35 35 35 35
transvector pressure 50 50 50 50 50 50 50 50 50
testing at Hills
tenacity 2.13 2.5 2.2 2.4 2.3 2.3 2.5 2.6 2.5
elongation 40 45 42 43 44 45 42 45 46
shrink (boiling water) 10 5 6 10 8 8 6
Bicomponent sample process conditions
BICOMPONENT 1.4%D PLA/1.4%D PLA 1.4%/3.
2% 1.4%D
PLA/PET 15-45-
2 15-45-
5 15-45-
9 15-47-2 15-48-1 15-48-2 15-
48-3 As spun dpf 18 18 19.3 19.2 18.55 total denier 829 829 750 600 697 760 denier /filament 5.7 5.7 5.2 4.16 4.8 5.3 No. orifices 144 144 144 144 144 144 144 Draw ratio 3.3 3.3 2.6 3.5 4.66 4 3.5 spin finish 756A 756A 756A 756A 756A 756A 756A Denier roll speed 296 296 296 296 296 296 296 denier roll temp amb. amb. amb amb amb amb amb # wraps 3 3 3 3 3 3 3 Draw roll 1 (tension roll)
298 298 298 298 298 298 298
tension roll temp amb. amb. 70 amb amb amb amb # wraps 4 4 4 4 5 5 5
Draw roll 2 300 300 790 300 300 300 300
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m/min draw roll 2 temp 80 80 120 78 77 77 77 # wraps 7 7 7 7 7 7 7
Draw roll 3 m/min
1000 1000 790 1050 1400 1200 1058
draw roll 3 temp 100-125
114 34 119 100 100 100
# wraps 9 9 9 9 9 9 9
Draw roll 4 m/min (relax)
950 950 890 1018 1335 1170 1040
draw roll 4 temp amb amb amb amb amb amb amb # wraps 7 7 7 7 7 7 7
testing at Hills tenacity 3.3 3 2.9 elongation 16 34 52 shrink (boiling water)
20 8 16 8 8
increased roll 3
Spin/draw line
Spin pac
Cooling wheel
Winder
Drawing
Draw roll 2
Draw roll 3
Steam
Texturiz
Stea
Denier
Draw roll 1
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ANALYTICAL--PLA values 48-(1-3) DSC--PLA values SHRINKAGE SINGLE FILAMENT TENACITY
Sample Mn
Mw
MP
PDI
Mz
Mz/
Mw
Mz+
1
Tg Tm % C
ryst
allin
ity
% H
2O S
hrin
k 10
0C
Std
Dev
Peak
Loa
d (g
)
Std
Dev
Elon
gati
on a
t Pe
ak
Load
(cm
)
Std
Dev
Ult
imat
e El
onga
tion
%
015-45-02 75100 147979 133874 1.97 230219 1.56 317535 62.96 166.47 48 60.31 4.71 18.56 1.68 4.64 0.64 45.9015-45-05 69057 143332 128980 2.08 227271 1.59 317596 61.63 167.41 47.91 24.79 4.92 17.18 0.76 5.08 0.53 50.5015-45-09 69616 142598 121392 2.05 228991 1.61 325843 60.24 168.2 50.15 33.23 2.59 17.28 1.18 4.42 1.12 43.9015-47-02 70445 135140 117250 1.92 211530 1.57 296285 61.27 157.85 41.37 28.02 2.67 17.93 2.23 4.23 0.4 42.2015-48-01 77604 145622 126558 1.88 228177 1.57 318147 170 23.67 24.90 0.93 17.3 2.21 2.5 0.33 25.2015-48-02 67880 145108 130550 2.14 233700 1.61 332552 168.61 23.59 15.73 0.68 16.21 0.61 3.16 0.34 31.4015-48-03 71620 147076 132653 2.05 234408 1.59 332993 167.82 23.56 11.32 1.30 18.02 0.51 5.45 0.76 54.2
Boiling Water Shrinkage
Sam
ple#
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Avg
Shr
ink
Std
Dev
015-45-02 4.6875 60.9375 4 66.66667 5.5625 53.64583 4.9375 58.85417 4.625 61.45833 60.3125 4.707711015-45-05 9.875 17.70833 8.5 29.16667 9.25 22.91667 9.0625 24.47917 8.4375 29.6875 24.79167 4.921806015-45-09 7.875 34.375 8.375 30.20833 8.3125 30.72917 7.6875 35.9375 7.8125 34.89583 33.22917 2.588495015-47-02 9 25 8.125 32.29167 8.625 28.125 8.75 27.08333 8.6875 27.60417 28.02083 2.665934015-48-01 9 25 9 25 8.875 26.04167 9.1875 23.4375 9 25 24.89583 0.931695015-48-02 10.125 15.625 10.0625 16.14583 10.0625 16.14583 10.0625 16.14583 10.25 14.58333 15.72917 0.679084015-48-03 10.83333 9.722222 10.5625 11.97917 10.625 11.45833 10.75 10.41667 10.4375 13.02083 11.31944 1.295702
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Material 1.4% D 3.2% D PETextrusion cond.Zone 1 200 200 280Zone 2 210 210 290Zone 3 220 220 290Zone 4 230 230 290Spin Head 230 230 280melt temp 230 228 274pressure extruder 750 750 750pack 1250 1150 1420pumpsize cc/rev 6 6 6 Hills trial Oct. 1998 for BCF and bicomponent
BCF samples15-36-2 15-36-5 15-36-9 15-36-13 15-36-17 15-36-21 15-36-25 15-36-30 15-36-33
As spun dpf 75.2 75 80 79.8 80.4 80.6 81 79 79.8total denier 1200 1190 1278 1272 1283 1286 1293 1260 1273denier /filament 17.9 17.8 19 19 19.1 19.2 19.3 18.8 19No. orifices 67 67 67 67 67 67 67 67 67Draw ratio 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2 4.2spin finish 756A 756A 756A 756A 756A 756A 756A 756A 756ADenier roll speed 156 156 156 156 156 156 156 156 156denier roll temp amb. amb. amb. amb. amb. amb. amb. amb. amb.# wraps 3 3 3 3 3 3 3 3 3steam between denier and draw 1 yes yes yes yes yes yes yes yes yesDraw roll 1 m/min 202 202 202 202 202 202 202 202 202draw roll 1 temp 70 70 70 70 70 70 70 70 70# wraps 5 5 5 5 5 5 5 5 5steam between draw 1 and 2 yes yes yes yes yes yes yes yes yesBCFDraw roll 2 m/min 660 660 660 660 660 660 660 660 660draw roll 2 temp 130 130 130 130 130 130 130 130 130# wraps 17 17 17 17 17 17 17 17 17
Draw roll 3 m/min 670 670 670 670 670 670 670 670 670draw roll 3 temp 80 80 80 80 80 80 80 80 80# wraps 10 10 10 10 10 10 10 10 10texture jet temp 80 80 80 80 80 80 80 80 80texture jet pressure 50 50 50 50 50 50 50 50 50interlacer pressure 35 35 35 35 35 35 35 35 35transvector pressure 50 50 50 50 50 50 50 50 50
testing at Hillstenacity 2.13 2.5 2.2 2.4 2.3 2.3 2.5 2.6 2.5elongation 40 45 42 43 44 45 42 45 4shrink (boiling water) 10 5 6 10 8 8 6
114 bobbins at 350 filiments each were used for the staple production
6
9.6 BCF and Bicomponent Follow-Up Trials
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TRIAL: BCF Fiber Trial #BCF91220 By: Donavon Kirschbaum
Dates: March 22-24, 1999
Location: Hills Inc 7785 Ellis Road W. Melbourne, Fla
Key Contact: Donavon Kirschbaum (NatureWorks LLC) Arthur Talley (Hills)
Objective: Measure of success against stated Produce trilobal BCF 18-20 dpf at 1300 denier with 3.4%D PLA to be used for carpet fiber.
Samples were produced having the same characteristics as the 1.5%D used in the past. Heat setting and draw conditions needed to be optimized.
Evaluate four spin finishes supplied by Goulston
Samples were spun with the different finishes. Two looked ok two were poor. Testing underway
Pilot test to produce POY bicomponent trilobal fiber 72/36 self-bulking with 1.5%D/3.4%D PLA.
Two samples were produced. One at 2000 m/min. and one at 3200 m/min. Tenacity was low (1g/denier) however, bulking looks good.
Reference: 15-62-67 Equipment
Hills spin/draw line: bicomponent with 2-1.25 in. extruders. Spin pack: trilobal 67 holes for BCF Spin pack: 144 hole .35 mm Barmag winder capable of high speed spinning (see figure below)
Materials:
PLA lot
# NB1528P106 MN 88.5, Mw 173, PDI 1.96, Color 48.4, res. lactide .09%, Percent D 3.4 GMID 112681
# MF0128P105 MN88.9k, Mw 193.8, 1.5%D, MFI 6.6, color 38, %res .21, GMID 112679
Unexpected occurrences:
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• POY samples had low tenacity (1 g/denier) the goal is 3. Process development is needed to increase the value.
Key learning’s: BCF using 3.4%D PLA • 3.4% D polymer behaved similar to the 1.5% D used in the past for BCF. The
1300/67 trilobal fiber had the following properties: • 2-2.5 g tenacity • 45-50% elongation • 10% shrink in boiling water
• Heat setting the 3.4% D polymer requires longer residence time on heat set rolls. 25 wraps at 700 m/min. were needed to get 10% shrink vs. 15 wraps for 1.5%D. This may be a problem on commercial lines?
• Draw ratio increased from 4.2 (1.5%D) to 4.6 (3.4%D) • TIO2 was not used to get the results. TIO2 improves fiber breakage thus with TIO2
the process should improve. Spin Finish • Four finishes from Goulston Technologies and a silicone were tested.
• Lurol 7275- used in the past and works fairly well • Lurol NF-6004- • Lurol PP-8102GL-20 • Lurol PP-3772-20 • Formisil 45 from OSI chemicals lot# 23555D041095
• Lurol 7275 and Lurol NF-6004 had the most favorable results. The other two inhibited fiber breakage and poor spinability.
• Goulston is doing a full evaluation of the spin finish along with a 756A (which translates into Lurol number PP5656)
POY reference 15-67 • Two samples were produced as a first step to evaluate the ability to produce
bicomponent POY trilobal fiber for self-bulking low denier yarn. A 1.5%D PLA and a 3.4%D PLA were used.
• The idea is if the fiber is spun at high enough speed (~ 3,000 m/min) the low % D will inhibit low boiling water shrink whereas the 3.4% D will have high shrink thus creating self bulk.
• A Barmag winder was placed directly under the spin head. • Samples were spun at 2,000 and 3,200 m/min. • Process temperatures: Temperature zone 1 zone2 Zone 3 Melt Pressure Amp East 3.4 180 220 230 225 1480 11 West 1.5 200 210 227 225 1970 8.5 • Tenacity was low at around 1 g/denier Next Step: • Send Goulston the finish samples to evaluate.
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• Evaluate samples of BCF produced with 3.4% D and determine the feasibility of the product being produced commercially.
• Evaluate bicomponent POY samples and determine the feasibility of producing. (longer term)
• Guilford is planning a trial to produce a mono-component POY PLA continuous fiber.
Process conditions: Polymer 3.4% D Extrusion cond.
Zone 1 200Zone 2 210Zone 3 220Zone 4 230Spin Head 230melt temp 228Screen pack 150pressure extruder 750pack 1028pump size cc/rev 6
DRAWING Notebook ref. 15-62-9
run # 9 Denier roll 156
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Draw roll 1 speed
162
temperature 70 wraps 15
Draw roll 2 speed
740
temperature 100 wraps 10
aw roll 3 speed 735 temperature 80 wraps 14 draw ratio 4.7 spin finish lurol
7275 spin finish setting
150
denier 1170 tenacity 2.3 elongation 47 shrinkage boiling H20
10.8
For comprehensive details click on spread sheets below Hills testingnotebook ref. 15-62-1 15-62-2 15-62-3 15-62-4 15-62-5 15-62-6
run # 1 2 3 4 5 6Denier roll 156 156 156 156 156 156
Draw roll 1 speed 162temperature 70wraps 15
Developing conditions for 3.4%D PLA
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A N A L Y T I C A L
S a m p le %D
% R
esid
ual L
acti
de
Mn
Mw
MP
PDI
Mz
Mz/
Mw
Mz+
1
0 1 5 -6 2 -0 1 3 .4 0 .0 5 8 6 7 7 4 1 6 8 2 9 0 1 4 8 8 4 2 1 .9 4 2 5 8 5 4 4 1 .5 4 3 5 5 5 3 40 1 5 -6 2 -0 2 0 .0 5 8 6 7 3 2 1 6 9 1 5 0 1 5 3 1 3 3 1 .9 5 2 6 1 4 9 5 1 .5 5 3 6 2 3 8 80 1 5 -6 2 -0 3 0 .0 5 8 5 7 8 3 1 6 6 9 7 0 1 5 2 1 9 7 1 .9 5 2 5 7 0 8 3 1 .5 4 3 5 3 3 5 20 1 5 -6 2 -0 4 0 .0 4 8 7 0 6 0 1 6 6 7 5 4 1 5 1 7 2 7 1 .9 2 2 5 6 0 2 6 1 .5 4 3 5 2 7 7 50 1 5 -6 2 -0 5 0 .0 4 8 5 0 5 0 1 6 5 1 9 4 1 4 4 0 8 6 1 .9 4 2 5 4 5 4 1 1 .5 4 3 5 1 6 0 1
Boiling Water Shrinkage
Sam
ple#
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
015-62-01 1.75 85.42 11.06 7.81 1.94 83.85 2.00 83.33 2.00015-62-02 5.81 51.56 4.31 64.06 4.19 65.10 4.31 64.06 4.69015-62-03 6.31 47.40 6.63 44.79 7.13 40.63 6.25 47.92 7.38015-62-04 8.13 32.29 6.56 45.31 7.88 34.38 7.44 38.02 7.88015-62-05 7.88 34.38 7.25 39.58 8.63 28.13 7.31 39.06 8.94015-62-06 10.69 10.94 10.75 10.42 10.75 10.42 10.56 11.98 10.38015-62-07 10.00 16.67 9.88 17.71 10.19 15.10 10.13 15.63 10.31015-62-08 10.88 9.38 10.88 9.38 10.81 9.90 11.06 7.81 10.63015-62-09 10.69 10.94 10.88 9.38 10.75 10.42 10.69 10.94 10.81015-65-10 11.19 6.77 11.13 7.29 11.25 6.25 10.94 8.85 11.25015-65-11 10.56 11.98 10.00 16.67 10.25 14.58 10.50 12.50 10.63
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Spin/draw line
Spin pac
Cooling wheel
Winder
Drawing
Draw roll 2
Draw roll 3
Texturiz
Stea
Denier
Steam
Draw roll 1
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Hills testingnotebook ref. 15-62-1 15-62-2 15-62-3 15-62-4 15-62-5 15-62-6 15-62-7 15-62-8 15-62-9 15-62-10 15-62-11 15-62-12 15-62-13 15-62-14 15-62-15
run # 1 2 3 4 5 6 7 8 9 10 11 12 13 14Denier roll 156 156 156 156 156 156 156 156 156 156 156 156 156 156 156
Draw roll 1 speed 162temperature 70wraps 15
Draw roll 2 speed 700 740 700 740temperature 100 110 130 135 145 135 130 135 130 127 135wraps 10 15 25Draw roll 3 speed 685 691 735 690 735temperature 80wraps 14draw ratio 4.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 4.7 0.0 0.0 0.0 0.0 4.5 4.7spin finish lurol 7275 Lurol NF
15
- Lurol PP- Lurol PP- silicone F no finish 7275spin finish setting 150denier 1420 1429 1415 1425 1440 1440 1250 1258 1170 1210 1187 1155 1175tenacity 2.3 1.8 2 2 1.8 2 2.25 1.95 2.3 2.26 2.4? 1.9 2.6elongation 29 31 45 49 47 50 49 46 47.5 50.6 33 54shrinkage boiling H2 80 70 40 35 17 8.7 12.5 11 10.8 8 14 27 9
New
day
similat to 7275
Problem
s with fiber breakage (poor)
High fiber breakage
Ran very poor no sam
ple taken
went back to original conditions
Developing conditions for 3.4%D PLA Evaluating spin finishes
ANALYTICAL
Sample %D
% R
esid
ual L
acti
de
Mn
Mw
MP
PDI
Mz
Mz/
Mw
Mz+
1
015-62-01 3.4 0.05 86774 168290 148842 1.94 258544 1.54 355534015-62-02 0.05 86732 169150 153133 1.95 261495 1.55 362388015-62-03 0.05 85783 166970 152197 1.95 257083 1.54 353352015-62-04 0.04 87060 166754 151727 1.92 256026 1.54 352775015-62-05 0.04 85050 165194 144086 1.94 254541 1.54 351601015-62-06 0.08 80591 165124 150033 2.05 255402 1.55 351054015-62-07 0.04 83715 166429 152024 1.99 259682 1.56 364709015-62-08 0.04 84661 166598 155098 1.97 258222 1.55 358334015-62-09 0.04 83696 165913 151320 1.98 257099 1.55 356307015-65-10 0.04 85461 166746 150041 1.95 258047 1.55 358750015-65-11 0.04 82387 164868 150594 2 258067 1.57 365810015-65-12 0.04 84154 165847 148149 1.97 256318 1.55 354552015-65-15 0.04 83518 165422 165422 1.98 255768 1.55 353850015-67-01 bico 0.08 77346 159246 159246 2.06 258118 1.62 385821015-67-02 bico 0.06 77098 158422 158422 2.05 253792 1.6 369522015-67-03 purge 0.05 83351 167526 167526 2.01 261358 1.56 366860015-67-04 purge 0.08 93754 192973 192973 2.06 315845 1.64 482782
015-69-01 180.47 5.7 3.34 0.39 13.5 1.6 45.8 3.04 1.83
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DSC- 1st Upheat DSC- 2nd Upheat SHRINKAGE
Sample Tg Tm % C
ryst
allin
ity
Tg Tm % C
ryst
allin
ity
% H
2O S
hrin
k 10
0C
Std
Dev
015-62-01 161.64 35.9 58.62 159.83 0.98 68.75 34.08015-62-02 161.5 36.44 58.94 158.83 1.29 61.15 5.58015-62-03 160.19 38.95 58.59 158.77 1.3 43.85 4.14015-62-04 160.24 38.76 58.42 158.8 0.46 36.88 5.15015-62-05 160.12 38.81 58.39 159.08 0.58 33.33 6.35015-62-06 160.45 38.13 59.08 159.3 0.15 11.46 1.33015-62-07 160.8 36.98 58.94 159.19 1.63 15.83 1.41015-62-08 162.42 37.63 59.26 159.84 0 9.58 1.31015-62-09 160.9 39.73 60.26 159.68 0 10.31 0.68015-65-10 160.08 43.27 58.91 158.28 0.59 7.08 1.08015-65-11 160.37 40.89 59.77 158.37 0.56 13.44 2.16015-65-12 160.81 40.63 60.07 158.79 0.11 19.06 1.08015-65-15 160.98 38.98 58.27 159.37 0 8.85 0.37015-67-01 61.63 161.67 27.42 59.3 164.7 0 couldn't get off the roll015-67-02 61.76 162.55 17.15 357.49 805.9j/g 84.79 1.74015-67-03 62.1 157.3 3.73 61.11 155.78 1.73015-67-04 63.61 168.43 5.63 61.94 167.59 3.86
015-69-01 0.1 98.69
MULTIFILAMENT TENACITY
Sample Peak
Loa
d (g
)
Std
Dev
Elon
gati
on a
t Pe
ak
Load
(cm
)
Std
Dev
Ult
imat
e El
onga
tion
% St
dDev
Fibe
r M
odul
us
(g/d
en)
Std
Dev
Fibe
r Te
naci
ty
(g/d
en)
Std
Dev
015-62-01 2515.87 201.76 8.03 0.68 40.3 2.6 24.63 2.78 1.77 0.14015-62-02 2140.07 171.75 8.48 1.34 43.7 3.8 19.01 3.15 1.5 0.12015-62-03 2046.39 374.45 8.52 1.21 42.2 2.4 22.95 1.14 1.45 0.26015-62-04 1855.14 184.6 8.48 1.54 46.9 1.5 22.32 1.08 1.28 0.13015-62-05 1514.16 108.05 7.66 1.32 9.5 0.7 24.77 4.14 1.05 0.08015-62-06 1368.13 198.35 6.16 2.48 35.3 8.5 23.86 1.64 0.95 0.14015-62-07 2230 179.46 10.2 0.63 45.3 2.7 22.94 2.23 1.8 0.14015-62-08 2380.21 313.13 11.09 0.97 48.7 2 20.95 1.38 1.89 0.25015-62-09 1921.64 208.14 9.21 0.57 41.2 2.3 24.39 6.02 1.64 0.18015-65-10 2764.41 143.17 11.54 0.43 49 1.8 23.77 1.78 2.28 0.12015-65-11 2365.37 366.32 10.36 0.64 45.1 1.1 25.4 2.27 1.99 0.31015-65-12 1365.49 254.91 5.52 1.79 29.3 5.3 33.39 0.74 1.18 0.22015-65-15 2869.33 63.83 12.19 0.22 51.4 0.9 24.6 0.83 2.44 0.05015-67-01 55.73 0.27 3.28 0.21 13.1 0.9 44.16 0.94 1.39 0.01015-67-02 139.26 6.75 11.82 0.29 46.9 1.4 31.59 2.21 1.12 0.05015-67-03015-67-04
015-69-01
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SINGLE FILAMENT TENACITY FILAMENT PROP
Sample Peak
Loa
d (g
)
Std
Dev
Elon
gati
on a
t Pe
ak
Load
(cm
)
Std
Dev
Ult
imat
e El
onga
tion
% St
d D
ev
Fibe
r M
odul
us
(g/d
en)
Std
Dev
Fibe
r Te
naci
ty
(g/d
en)
Std
Dev
Den
ier
Comments
015-62-01 68.01 12.03 4.47 1.44 44 14.2 43.49 6.2 3.21 0.57015-62-02 58.5 5.11 3.37 0.31 33 3.1 33.5 18 2.74 0.24015-62-03 69.34 9.59 3.63 0.27 36 2.6 44.3 4 3.28 0.45015-62-04 59.48 10.9 4.09 0.53 40 5.2 41.2 8 2.75 0.5015-62-05 55.27 12.42 4.34 0.26 43 2.6 32.07 7.2 2.57 0.58015-62-06 61.1 10.04 4.47 0.65 44 6.4 34.09 5.3 2.84 0.47 getting low 015-62-07 55.57 11.81 4.56 0.64 45 6.2 38.83 6.1 3 0.64 25 wraps at015-62-08 53.56 4.02 4.47 0.31 44 3.1 35.64 4.3 2.85 0.21 25 wraps at015-62-09 50.9 7.82 4.13 0.42 41 4.2 47.51 9.9 2.92 0.45 lurol 7275015-65-10 54.21 3.87 4.65 0.26 46 2.5 41.13 8 3.1 0.22 lurol NF-60015-65-11 54.23 10.76 3.99 0.25 39 2.5 40.16 7.3 3 0.21 Lurol PP-81015-65-12 47.08 8.14 3.37 0.59 33 5.8 42.48 4 2.73 0.47 lurol PP-37015-65-15 50.56 2.81 4.58 0.24 45 2.4 37.22 5.2 2.88 0.16 lurol 7275015-67-01 unable to get one filament without breaking trilobal S/S 015-67-02 3.93 0.27 0.7 0.69 42 12.7 26.84 7.7 1.14 0.08 trilobal S/S 015-67-03 purge015-67-04 purge
015-69-01 180.47 5.7 3.34 0.39 14 1.6 45.8 3 1.83 0.1 # sample 15-67-2
Boiling Water Shrinkage
Sam
ple#
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Afte
r Len
gth
%S
hrin
k
Avg
Shr
ink
Std
Dev
015-62-01 1.75 85.42 1.69 85.92 1.94 83.85 2.00 83.33 2.00 83.33 84.37 1.21015-62-02 5.81 51.56 4.31 64.06 4.19 65.10 4.31 64.06 4.69 60.94 61.15 5.58015-62-03 6.31 47.40 6.63 44.79 7.13 40.63 6.25 47.92 7.38 38.54 43.85 4.14015-62-04 8.13 32.29 6.56 45.31 7.88 34.38 7.44 38.02 7.88 34.38 36.88 5.15015-62-05 7.88 34.38 7.25 39.58 8.63 28.13 7.31 39.06 8.94 25.52 33.33 6.35015-62-06 10.69 10.94 10.75 10.42 10.75 10.42 10.56 11.98 10.38 13.54 11.46 1.33 getting low shrink 25 wraps at 133C ro015-62-07 10.00 16.67 9.88 17.71 10.19 15.10 10.13 15.63 10.31 14.06 15.83 1.41 25 wraps at 130 C015-62-08 10.88 9.38 10.88 9.38 10.81 9.90 11.06 7.81 10.63 11.46 9.58 1.31 25 wraps at 135C015-62-09 10.69 10.94 10.88 9.38 10.75 10.42 10.69 10.94 10.81 9.90 10.31 0.68 lurol 7275015-65-10 11.19 6.77 11.13 7.29 11.25 6.25 10.94 8.85 11.25 6.25 7.08 1.08 lurol NF-6004015-65-11 10.56 11.98 10.00 16.67 10.25 14.58 10.50 12.50 10.63 11.46 13.44 2.16 Lurol PP-8102GL-20015-65-12 9.50 20.83 9.81 18.23 9.75 18.75 9.69 19.27 9.81 18.23 19.06 1.08 lurol PP-3772-20015-65-15 10.94 8.85 11.00 8.33 10.94 8.85 10.88 9.38 10.94 8.85 8.85 0.37 lurol 7275015-67-01 trilobal S/S 1.5/3.4 %D spun at 3200 m015-67-02 2.00 83.33 2.00 83.33 1.88 84.38 1.75 85.42 1.50 87.50 84.79 1.74 trilobal S/S 1.5/3.4 %D spun at 2000 m015-67-03 purge015-67-04 purge
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9.7 Comparison of Bicomponent Properties
BiComponent Fiber Property Comparison
Polymer Reference (for nonCoPET (Sheath/Core)
CoPET (Sheath/Core)
PLA / PLA (Sheath/Core)
PLA / PLA (Sheath/Core)
PLA / PET (Sheath/Core)
PLA / PET (Sheath/Core)
PLA / PET (Sheath/Core)
Properties PLA Properties) 110C / 260C 175C / 260C 5.2%D / 1.4% D 10.5% / 1.4% 1.4% D / PET 7.5% D / PET 5.2% D / PETstrength-tenacity (g/den) Wellman 4.3 4.75 3.92 3.98 5.24 5.51 5.75Elongation @ Break (%) Wellman 60% 60% 31.20% 26.00% 35.10% 36.40% 34.60%
Specific Gravity Wellmanmarginally lower than PET
marginally lower than PET 1.25-1.28 1.25-1.28
Tm - melting point (C) Wellman 110 175 151.6 / 167.58 133.19 / 167.55 173.13 / 254.73 151.43 / 256.29 153.58 / 257.26softening sticking point (C) Wellman 70Tg (C) Wellman 67 67 69.93 62.26 / 71.92
%Crystallinity (DSC) Wellman 0no greater than PET 34.69 30.68 PLA=25.8 PLA=14.63 PLA=15.61
Notes: Base Properties for sheath and core Bicomponent material, 50/50 A/B structure, 4-6 dpf.
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9.8 Typical Staple Fiber Spinning System6
9.9 Typical PET Drawline Recommended for PLA Bicomponent Processing5
Index for Drawing Equipment ID Description ID Description ID DescriptionI Can Creel R Cold draw stand W1 Tow distribution system L Tow reed S Finish applicator W2 Tow take off system M Tension stand S2 Dancer Rolls X Cutter N Pre dip bath T Ply bars Y Staple transport system O Heated draw stand U Steam chest Y2 Condenser P Hot air, steam or immersion bath V Crimper Z Baler Q Heatsetting calendar W Dryer
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