Polyethylene (PE) and polyethylene-block-poly(ethylene glycol) (PE-PEG) grafted with N,N,N',N'-tetraethyldiethylenetriamine (TEDETA) were used as soluble and recoverable supports for copper bromide mediated atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA). The PE chain length and poly(ethylene glycol) (PEG) spacer strongly affected the catalytic activity and control of the polymerization. With PE as a catalyst support, the catalytic activity and control of the polymerization were low and decreased as the PE support's chain length increased. The adverse effects of the PE support were minimized by using PEG as spacer to graft the catalyst onto the PE support. The PE25-PEG(4)-TEDETA-CuBr and PE16-PEG(10)-TEDETA-CuBr were found effectively mediated ATRP of MMA. The recycled PE-supported catalysts had low activity because of catalyst side reactions and/or catalyst loss, but the PE25-PEG(4)-TEDETA-CuBr retained 90% activity upon recycling and had good control over the polymerization.