摘要 |
A process for producing polyolefin materials is disclosed which comprises the steps of (a) preparing a molded article of an ultra-high-molecular-weight polyolefin having a viscosity-average molecular weight of more than 500,000; (b) stretching said article by more than thirty-fold; (c) contracting the thus stretched article to an extent ranging from 0.3 to 80% in the direction of stretch; and (d) re-stretching the thus contracted article. The resulting polyolefin materials are improved in mechanical strength and elasticity modulus. |