high performance polyethylene fiber
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Transcript of high performance polyethylene fiber
High-performance Polyethylene Fibres
1. Introduction Polyethene, polyethylene, polythene A flexible waxy translucent polyalkene thermoplastic made in a variety of ways producing a polymer of varying characteristics.
LDPE: molecular weight 50,000 - 300,000 softening temperature 110 oC relative density 0.92
HDPE: molecular weight up to 3,000,000 softening temperature 130 oC relative density 0.945- 0.96
UHMW-PE: molecular weight up to 6,000,000
low moisture absorption
low coefficient of friction
highly resistant to abrasion
self lubricating
fibre commercialized in late 1970s by DSM
2. Spinning of Polymers
Spinning: A specialized form of extrusion that uses a spinneret to manufacture multiple continuous multi filaments of polymer
Types of Spinning:
Wet Spinning
Dry Spinning
Melt Spinning
Gel Spinning
Wet Spinning:
Polymers is dissolved in solvent
Precipitation of polymer
Solidification of polymers at emergence from the spinneret
Acrylic, spandex, modacrylic,
Dry Spinning:
Polymers is dissolved in solvent
Solidification of polymer through evaporating the solvent
Acetate, triacetate, acrylic, modacrylic, spandex
Melt Spinning:Polymer is melted
Solidification of cooling after extrusion
Nylon, polyester, olefins
Gel Spinning:
Preparation of gel
At extrusion fibres are first dried and than cooled in a liquid bath
Dyneema, spectra
High-performance Polyethylene Fibres
3. Production
Polymer Preparation– UHMW-PE is synthesized based on metallocene
catalysts from monomers of ethylene (C2h4)
– HDPE molecules have 700- 1,800 monomers
– UHMW-PE molecules have 100,000-250,000 monomers
Product Types
– Powder
– Rods Sheets
– Fibres
3. Production
Gel Spinning
– HPPE are produced as Dyneema by DSM in Netherlands and Toyobo/DSM in Japan and Spectra by Honeywell in USA
– Feedstock Polymer
– Spinning Solution
– Gelation and crystallization
– Drawing
3. Production
4. Structure and Properties
Fibre Form- Produced as Multifilament Yarn (0.32-10 dpf, 5 N/tex, 120 N/tex, circular cross-section, smooth skin)
Structure and Morphology (highly crystalline > 80%, non-crystalline is an interphase form characterized by high density, orientation and restricted mobility of molecular chains.
Structure and Properties• Density 0.97-0.98 gm/cm3
Commercially Available FibresDensity(kg/m3)
Den/fil(dpf)
Tenacity(N/tex)
Modules (N/tex)
ElongationTo break (%)
DSM HPF
Dyneema SK 60 970 1 2.8 91 3.5Dyneema SK 65 970 1 3.1 97 3.6Dyneema SK 75 970 2 3.5 110 3.8
Dyneema SK 76Toyobo
970 2 3.7 120 3.8
Dyneema SK 60 970 1 2.8 91 3.5
Dyneema SK 71Honeywell
970 1 3.5 122 3.7
Spectra 900 970 10 2.6 75 3.6Spectra 1000 970 5 3.2 110 3.3Spectra 2000 970 3.5 3.4 120 2.9