Fibers and oriented films of polypropylene higher .alpha.-olefin copolymers
AssigneeExxon Chemical Patents Inc.
InventorsJames J. McAlpin, Glenn A. Stahl
Life of this patent
Estimating the term…
Abstract
A propylene, .alpha.-olefin copolymer, where the .alpha.-olefin has 5 or more carbon atoms made with a metallocene catalyst system provides substantially higher cold flow resistance from when the propylene copolymer is made with an .alpha.-olefin having 4 or less carbon atoms. Other properties such as ultimate tensile strength and impact strength are substantially higher as well. Such polymers can be used to advantage in fibers, fabrics, and oriented films.
Claims17
An article comprising a copolymer of propylene and at least one alpha-olefin, said alpha olefin having 5 or more carbon atoms;
- said .alpha.-olefin being present in the range of from about 0.2 to about 6 mole percent based on the total moles of monomer in said copolymer, said copolymer having a M.sub.w /M.sub.n .ltoreq.5, said copolymer having a melting point in the range of from about 100.degree. C. to about 145.degree. C.;
- wherein said article has an R.sub.ms exceeding about 1.1.
An article comprising at least a first propylene .alpha.-olefin copolymer, said .alpha.-olefin being selected from the group consisting of 1-hexene, 4-methyl-pentene-1, and 1-octene;
- said copolymer being made utilizing a metallocene-alumoxane catalyst system, said alumoxane being a methyl alumoxane;
- wherein said .alpha.-olefin is present in the range of from about 1 to about 3 mole percent based on the total moles of monomer in said copolymer;
- wherein said copolymer having a M.sub.w /M.sub.n .ltoreq.2;
- said copolymer having a melting point in the range of from about 110.degree. C. to about 135.degree. C.;
- and
- said article having an R.sub.ms exceeding about 1.1.
Dependencies are inferred from the claim text.