PROCESS FOR MANUFACTURING POLYOLEFIN FILMS

摘要

A process for manufacturing a film of ultra-high molecular weight polyolefin includes (a) feeding an ultra-high molecular weight polyethylene with a weight average molecular weight of at least 500,000 gram/mole as a powder having a bulk density below 0.5 g/cm3 to a compaction zone of an isobaric double belt press; (b) subjecting the ultra-high molecular weight polyethylene powder in the compaction zone to an isobaric pressure to form a single layer sheet of compacted polyethylene at a temperature that is below the melting point of the polyethylene under process conditions and that is maintained within a temperature window of 2° C.; and (c) subjecting the sheet of compacted polyethylene to a rolling step and at least one stretching step at a temperature below the melting point of the polyethylene under process conditions.