The heating of a mixture of ethyl 2-(1,1-dimethylethylperoxymethyl)propenoate and atactic polypropylene allowed the grafting of ester and epoxide functions onto the polyolefin. This is attributed to an induced decomposition of this acrylic peroxide, due to the addition of macroradicals, arising from polypropylene, to the unsaturation followed by an S(H)i onto the peroxidic bond. (C) 2004 Elsevier Ltd. All rights reserved.