Radiation crosslinking and performance of ultra-high molecular weight polyethylene microporous membrane under different temperatures

Abstract

An ultra-high molecular weight polyethylene (UHMWPE) microporous membrane was affixed to a plate and heated to 126~127 °C, and its absorbed dose was controlled at 0 kGy, 25 kGy, 50 kGy, and 75 kGy irradiated by a high-energy electron beam. The effects of different absorbed doses on the cross-linking degree, tensile strength, puncture force, crystallinity, and temperature resistance of the UHMWPE microporous membranes under heated conditions were investigated. The crosslinking degree of the UHMWPE microporous membrane with an absorbed dose of 75 kGy was 97%, and the membrane integrity was maintained up to 12 h after boiling in xylene. The mechanical properties of the membrane degraded, and the tensile strength decreased from 151.8 to 75.3 MPa. The puncture force reduced from 4.31 to 2.74 N, exhibiting a 36% decrease. The crystallinity and thermal shrinkage ratio also decreased from 30.7% to 23.4% and from 95.8% to 1.8%, respectively. The scanning electron microscopy images demonstrated that the greater the absorbed dose, more significant was the pore closure of the UHMWPE microporous membrane.

Keywords

• high temperature radiation crosslinking
• ultra-high molecular weight polyethylene (uhmwpe) microporous membrane
• temperature resistance