A novel, efficient route for the crosslinking and creep improvement of high modulus and high strength polyethylene fibres

Abstract

A new route is presented for the chemical crosslinking of solution-spun, ultra-drawn Ultra-High-Molecular-Weight Polyethylene (UHMW-PE) fibres. UHMW-PE fibres with a range of draw ratio's, Young's moduli and tensile strengths were impregnated with a radical initiator using supercritical carbon dioxide as a carrier. After impregnation, the drawn fibres were crosslinked with ultra-violet light and fibres with a high gel content (> 90%) were obtained. It was found that the chemical crosslinking strongly reduces the plateau creep rate of the fibres and that the threshold stress for irreversible creep is enhanced. Simultaneously, the high Young's modulus and the high tensile strength of the drawn fibres are preserved which illustrates that the long term properties of the fibres (i. e. creep) are improved without a large sacrifice short term mechanical properties such as Young's modulus.