The branching copolymerization of 2-hydroxypropyl methacrylate (HPMA) with either ethylene glycol dimethacrylate (EGDMA) or bisphenol A dimethacrylate (BPDMA) as the branching agent has been carried out using atom transfer radical polymerization (ATRP) in methanol at 20° C. With EGDMA, soluble branched copolymers were obtained provided that less than one branching agent was incorporated per primary chain: higher levels of ...