Resilient, high strinkage propylene polymer yarn and articles made therefrom

Claim 1

Propylene polymer yarn of increased resiliency and shrinkage, compared to crystalline polypropylene homopolymer yarn, comprising a continuous strand of multiple monofilament fibers, the composition of matter of said fibers consisting essentially of a member of the group consisting of, amounts being expressed as weight %: I. a blend of crystalline polypropylene homopolymer at a concentration of about 10-70% of the blend, and (a) a random crystalline terpolymer consisting essentially of about 96.0-85.0% of propylene, about 1.5-15.0% of ethylene, and about 2.5-10% of a C 4 -C 8 alpha-olefin or (b) a random, crystalline, propylene polymer consisting essentially of propylene and about 1.5-20.0% of an olefin selected from the group consisting of ethylene and C 4 -C 8 alpha-olefins; and II. propylene polymer material optionally in a blend with crystalline, polypropylene homopolymer, said homopolymer being at a concentration up to about 70% of the blend, said propylene polymer material being selected from the group consisting of: (a) a composition of random, crystalline, propylene polymers consisting essentially of: (1) about 30-65% of a copolymer of about 80-98% propylene, and a C 4 -C 8 alpha-olefin, and (2) about 35-70% of a copolymer of propylene and ethylene and optionally about 2-10% of a C 4 -C 8 alpha-olefin, said copolymer containing about 2-10% ethylene when said C 4 -C 8 alpha-olefin is not present, and about 0.5-5% ethylene when said C 4 -C 8 alpha-olefin is present; (b) a composition of random, crystalline, propylene polymers and a predominantly ethylene copolymer, which composition consists essentially of: (1) about 15-35% of a terpolymer of about 90-93% propylene, about 2-3.5% ethylene, and about 5-6% C 4 -C 8 alpha-olefin, (2) about 30-75% of a copolymer of about 80-90% propylene, and a C 4 -C 8 alpha-olefin, and (3) about 20-60% of a copolymer of about 91-95% ethylene, and a C 4 -C 8 alpha-olefin; (c) a heterophasic, polyolefin composition consisting essentially of: (1) 90-55% of polymeric material selected from the group consisting of a polypropylene homopolymer having an isotactic index greater than 90, and a crystalline copolymer of propylene and an alpha-olefin of the formula CH 2 ═CHR, where R is H or C 2 -C 6 alkyl, said olefinic material being less than 10% of the copolymer, and (2) 10-45% of an elastomeric polymer of propylene and olefinic material selected from the group consisting of alpha-olefins of the formula CH 2 ═CHR, where R is H or C 2 -C 6 alkyl, said olefinic material being 50-70% of said elastomeric copolymer, and 10-40% of said elastomeric copolymer being insoluble in xylene at ambient temperature.