Verfahren zur Herstellung einer porösen Polypropylenfolie mit hoher Zugfestigkeit

摘要

A high strength porous film of polypropylene which comprises predominantly a polypropylene resin and possesses the following physical properties: (1) a tensile strength of at least 35 MPa in two orthogonal directions; (2) a porosity of not more than 80%; and (3) a moisture permeability of at least 20 g/m<2> day.