PREPARATION OF ULTRA HIGH MOLECULAR MASS POLYETHYLENE AND ULTRA HIGH MOLECULAR MASS POLYETHYLENE HAVING IMPROVED CROSSLINK ABILITY PREPARED THEREBY

摘要

The invention pertains to a method for the preparation of ultra high molecular mass polyethylene by polymerization in suspension or in gas phase in the presence of a chromium catalyst sitting on an alumosilicate support material. The chromium catalyst has been subjected to a fluorinating treatment and the polymerization is performed under low temperature conditions within a temperature range of from 50 to 100 °C. The invention pertains also to ultra heigh molecular mass polyethylene prepared by that method and having a density in the range of from 0.930 to 0.950 g/cm3.