Enhanced tensile properties of ultra‐high molecular weight polyethylene fibers by solubility improvement with mixed solvents

Abstract

AbstractThe tensile properties of ultra‐high molecular weight polyethylene (UHMWPE) fibers obtained from mixed solvents are addressed by virtue of improved solubility. In this work, olive oil (OO) was introduced as a poor solvent for the pre‐swelling of UHMWPE in decalin, and its mass percentage was intended to be 10, 20, 30, and 40 wt% of UHMWPE. Then UHMWPE fibers with high molecular weight retention and low entanglement were prepared with paraffin oil as spinning solvent by gel‐spinning and hot‐drawing. Unlike other samples, there is a more significant molecular chain disentanglement and higher molecular weight retention for UHMWPE fibers as OO addition is 20 wt%. Surprisingly, obtained UHMWPE fibers exhibit tensile strength up to 33.85 cN/dtex and tensile modulus of 1673.27 cN/dtex, with an increase of 24.0% and 32.3%, respectively, compared with that of UHMWPE fibers without decalin/OO pre‐swelling. Furthermore, the obtained UHMWPE fibers are accompanied by a marked improvement in melting temperature, crystallization and orientation.