A tetrahydrofuran (THF) solution of the living random copolymer of methyl methacrylate (MMA) and glycidyl methacrylate (GMA) was prepared by the living anionic copolymerization of the two monomers, using 1,1-diphenylhexyllithium (DPHLi) as initiator, in the presence of LiCl ([LiCl]/[DPHLi](o) = 3), at -50 degrees C. The copolymer thus obtained has a controlled composition and molecular weight and a narrow molecular weight distribution. By introduction of an anionic living polystyrene (poly(St)) or anionic living polyisoprene (poly(Is)) solution into the above system at -30 degrees C, a coupling reaction took place and a graft copolymer with a polar backbone and nonpolar side chains was produced. The solvent used in the preparation of the living poly(St) or poly(Is) affects the coupling reaction. When benzene was the solvent, a graft copolymer of high purity, controlled graft number and molecular weight, and narrow molecular weight distribution (M-w/M-n = 1.11-1.21) was obtained. In the coupling reaction, the living poly(St) reacted only with the epoxy groups and not with the carbonyls of the backbone polymer.