DEVELOPMENT OF HIGH MODULUS POLYMERS IN PLANAR DIRECTIONS.

Multiaxially oriented polymers with high tensile properties in planar directions have been prepared by fibrillar crystallization under curvilinear flow conditions. The approach was demonstrated with the preparation of multiaxially oriented films of high density polyethylene and the aromatic, copolyester of poly(ethylene terephthalate) and 80 mole % p-acetoxy-benzoic acid using torsional flow conditions in molding applications. The mechanical properties of the multiaxially oriented films are discussed in terms of the flow conditions.