Blends of co-precipitated hydrogenated ethylene-dicyclopentadiene and elastomeric polymers to provide impact modified structural polyolefins

A process for preparing polymeric compositions suitable for molding into structural polyolefin products, which process comprises:

• A) dissolving in a liquid reaction medium from 60 to 95 parts by weight of ethylene-dicyclopentadiene copolymer component having:
• i) a dicyclopentadiene-derived comonomer content of from 30 mole % to 55 mole % with at least 10mol% of said dicyclopentadiene-derived comonomers having residual double bond moieties therein;
• ii) a weight average molecular weight, Mw, of from 100,000 to 800,000 g/mole;
• and
• iii) a glass transition temperature, Tg, of from 105° C. to 170° C.;
• B) co-dissolving with said ethylene-dicyclopentadiene copolymer component in said liquid reaction medium from 5 to 40 an elastomeric polymer component having a glass transition temperature, Tg, which ranges from −70° C. to −5° C.;
• C) subjecting said liquid reaction medium containing said ethylene-dicyclopentadiene copolymer component and said elastomeric polymer component to hydrogenation conditions in-situ, effective to completely hydrogenate the residual double bond moieties within said ethylene-dicyclopentadiene copolymer component and the elastomeric polymer component;
• and
• D) co-precipitating the resulting completely partially hydrogenated ethylene-dicyclopentadiene copolymer component and completely hydrogenated elastomeric polymer component from said liquid reaction medium as a co-precipitated polymeric composition With a precipitation-inducing agent which renders the polymer components insoluble in said liquid reaction medium.