US 7,579,387 B2
Radiation-crosslinked polyolefin compositions
Peter Jackson, Toronto (Canada); Marcus P. Heydrich, Mississauga (Canada); and Karen Schnuelle, Cambridge (Canada)
Assigned to ShawCor Ltd., Toronto, Ontario (Canada)
Filed on Jun. 06, 2008, as Appl. No. 12/134,838.
Application 12/134838 is a continuation of application No. 11/048833, filed on Feb. 02, 2005, granted, now 7,456,231.
Prior Publication US 2008/0242758 A1, Oct. 02, 2008
Int. Cl. C08F 2/46 (2006.01); C08J 3/28 (2006.01)
U.S. Cl. 522—112  [522/109; 522/110; 522/111; 522/71; 522/74; 522/150; 522/157; 522/158; 522/161; 522/184; 522/186; 522/189; 522/906; 525/211; 525/221; 525/227; 525/222; 525/240; 525/70; 525/198; 525/195; 525/191; 525/197; 264/234; 264/232; 264/236; 264/17; 264/237; 264/18] 41 Claims
 
1. A radiation-crosslinked article comprised of a polymer composition, the polymer composition comprising:
(a) a polyethylene; and
(b) from about 5 to 40 percent by weight of a polypropylene selected from the group consisting of polypropylene homopolymer and polypropylene copolymers;
(c) from about 5 to about 25 percent by weight of a compatibilizer;
wherein the compatibilizer comprises a copolymer of ethylene with a higher alpha olefin and is different from said polyethylene;
wherein the amount of said compatibilizer present in the composition is such that the combined amount of said polyethylene and said compatibilizer is at least 60 percent by weight of the composition; and
wherein the article is crosslinked by exposure to radiation and possesses a sufficient degree of crosslinking such that when the article is heated to a temperature above the crystalline melting point of the polypropylene, it is softened but does not become liquid.