High modulus, low creep strain polyalkene polymer materials

Claim 1

An oriented polymer material having a weight average molecular weight greater than 300,000; a ratio of weight average molecular weight to number average molecular weight greater than 5; and a creep strain at room temperature of less than 3% after 15 hours under a stress which produces an initial strain of 1% after 10 seconds, said polymer material being selected from the group consisting of ethylene/propylene block copolymers, ethylene/hexene-1-copolymers, polypropylene or a substantially linear polymer of ethylene containing at least 95% by weight of ethylene and having a density from 0.91 to 1.0 gm/cm 3 as measured by the method of British Standard Specification No. 2782 (1970) method 590B on a sample prepared according to British Standard Specification No. 3412 (1966) Appendix A and annealed according to British Standard Specification No. 3412 (1966) Appendix B(1).