Six-or four-functional methacrylate monomers were prepd. by addn. of (i) glycidyl methacrylate and an adduct of glycidyl methactylate with methacrylic acid to phthalic anhydride or (ii) glycidyl methacrylate to 1,5-di-o-phthaloyloxypenane, resp., and used for copolymerization with styrene (dibenzoyl peroxide initiator) for 2.5 h at 60 degrees C and for 24 h at 90 degrees C. Both uncured mixts. and the copolymers were studied for thermal, mech. and rheoL properties. Full conversion of double bonds was not achieved under conditions of the copolymerization.