UHMWPE Fibre Manufacturing Process
topic
Gel spinning process: (1) UHMWPE (MW 3-6 million g/mol, 10-20× conventional PE) dissolved in solvent (decalin, paraffin oil) at 1-5% concentration and 150-200°C, (2) extrusion through spinneret and rapid cooling forming gel fibre, (3) solvent extraction with volatile solvent, (4) multi-stage ultra-drawing at 120-150°C with total draw ratio 100-300× (vs. 3-5× for conventional fibres), (5) heat setting under tension at 145-150°C. Achieves 95-98% chain orientation vs. 60-70% for conventional fibres.
Role
Gel spinning enables drawing of ultra-high MW polymer (impossible via melt spinning due to viscosity) to extreme orientation, creating extended-chain crystals (crystallinity 80-85%) with tensile strength approaching theoretical C-C bond strength (20-30% of theoretical vs. 5-10% for conventional polymers).