Method of producing polypropylene tapes

摘要

The present invention relates to a process for making polymer tapes utilizing metallocene catalysts. An isotactic propylene polymer is prepared by polymerizing propylene in the presence of an isospecific metallocene catalyst. The resulting polypropylene is heated, extruded and withdrawn as a sheet. The sheet is then slit longitudinally into tape segments and drawn in the longitudinal direction to a draw ratio of at least about 4.5:1 to produce an oriented tape. It has been found that these polypropylene tapes have different characteristics than those polypropylene tapes produced using Ziegler-Natta catalyst drawn at the same draw ratios.