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.

Abstract: Compositions comprising, based on the weight of the composition: A. Less than 50 wt % of a propylene-ethylene copolymer comprising between 8 and 20 wt % of units derived from ethylene, based on the total weight of the copolymer; B. At least 50 wt % of a filler; and C. Between greater than zero and 1 wt % of a titanate compound. The propylene-ethylene copolymer typically has a low crystallinity of between greater than zero and 35%, and the filler is typically an inorganic material such as aluminum trihydrate and/or calcium carbonate. Mono-alkoxy-titanate is representative of the titanate compounds that can be used in this invention.