BIAXIALLY ORIENTED POLYPROPYLENE FILM HAVING IMPROVED WATER VAPOR AND OXYGEN BARRIER PROPERTIES

摘要

A biaxially oriented polypropylene film is described. The base ply of the film essentially consists of a polypropylene prepared by means of a metallocene catalyst. This polypropylene is distinguished by a mean isotactic block length of greater than 40, an n-heptane soluble fraction of less than 1% and a ratio of the weight average molecular weight Mw to the number average molecular weight Mn of less than 4.