| abstract |
A graft copolymer (I), blendable with polyolefins to improve their tensile modulus and sag-resistance, is claimed comprising: (a) non-polar polyolefin trunk comprising units of (mixt.) ethylene, propylene, butylene or 4-methylpentene and opt. minor amt. units of (mixt.) 1-alkanes, vinyl esters/chloride or (meth)acrylic acids/esters; and (b) poly(meth)acrylate chain(s) covalently grafted to (a) in wt. ratio (b):(a) 1:9-4:1, comprising 80-100 wt.% methacrylic ester units, formula CH2=C(CH3)COOR (R = (substd.) alkyl/aryl or substd. alkaryl) and 0-20 wt.% units of other monomer comprising styrenic/other copolymerisable acrylic/monoethylencally-unsatd. monomer, or 0-5 wt.% maleic and/or itaconic acid/anhydride. Also claimed are: polymer blends; prepn. of (I) and blends; and process for improving mutual compatibility of polymers. |