Opaque polymeric films cavitated with syndiotactic polystyrene

摘要

A method for producing an opaque polymeric film comprises:(a) extruding a base layer comprising a polymeric matrix and at least one cavitating agent;(b) coextruding at least one additional layer on at least one side of the base layer;(c) cooling the coextruded multi-layer film; and then(d) orienting the film in at least the machine direction (MD);wherein at least said base layer contains a syndiotactic polystyrene polymer, and wherein said syndiotactic polystyrene polymer is in the form of solid, non-hollow particles during the orienting step (d).