Reactively Processed, High Heat Resistant Composition of Polypropylene and an Olefinic Interpolymer

Abstract

A propylene polymer is coupled with an olefinic interpolymer by a process comprising contacting under reactive processing conditions at least: A. 10 wt % of at least one propylene polymer; B. 10 wt % of at least one olefinic interpolymer; C. 35 wt % of at least one metal hydrate; and D. A coupling amount of a coupling agent, each weight percent based on the combined weight of the propylene polymer, olefinic interpolymer and metal hydrate. Wire and cable insulation sheaths made from compositions comprising the coupled polymer exhibit desirable heat resistance.

1 . A process for coupling a propylene polymer with an olefinic interpolymer, the process comprising contacting under reactive processing conditions which includes a temperature of 180-250° C.:
 A. At least 10 wt % of at least one propylene polymer; 
 B. At least 10 wt % of at least one olefinic interpolymer other than the propylene polymer of (A); 
 C. At least 35 wt % of at least one of aluminum hydroxide and magnesium hydroxide; 
 D. 0.1 to 6 weight percent of a vinyl silane; and 
 E. Optionally, one or more additives. 
 
     
     
         2 - 4 . (canceled) 
     
     
         5 . The process of  claim 1  in which the olefinic interpolymer is at least one of very low density polyethylene; homogeneously branched, linear ethylene/α-olefin copolymer; homogeneously branched, substantially linear ethylene/α-olefin polymer; linear medium density polyethylene, linear low density polyethylene, ultra low density polyethylene and an olefinic multi-block copolymer. 
     
     
         6 . The process of  claim 1  in which the olefinic interpolymer is a homogeneously branched, substantially linear ethylene/α-olefin polymer with a content of units derived from ethylene content of at least 80 wt % and a density of at least 0.870 g/cm 3 . 
     
     
         7 . (canceled) 
     
     
         8 . The process of  claim 1  in which an antioxidant is present in an amount of 0.05 to 5 wt % based on the combined weight of the propylene polymer, olefinic interpolymer and metal hydrate. 
     
     
         9 . A composition made by the process of  claim 1 . 
     
     
         10 . The composition of  claim 9  in the form of a wire or cable insulation sheath.