Polyethylene-graft-poly(n-butyl acrylate) (PE-g-PBA) and polyethylene-graft-poly(methyl methacrylate) (PE-g-PMMA) were prepared through the combination of metallocene-catalyzed ethylene/ 10-undecen-1-ol copolymerization and conversion of the copolymer into a macroinitiator for atom transfer radical polymerization (ATRP). Well-defined acrylate and methacrylate graft copolymers were successfully prepared under dilute ATRP conditions. This was confirmed by analyses of the detached side chains. The molecular weights of both PBA and PMMA side chains agreed with predicted values, and molecular weight distributions were narrow. The PE-g-PMMA was evaluated as a compatibilizer for a blend of PE and PMMA and demonstrated the potential of such nonpolar/polar graft copolymers as a compatibilizing agent.