Synthesis of block copolymers via redox polymerization

Polymerization and copolymerization of vinyl monomers such as acrylamide, acrylonitrile, vinyl acetate, and acrylic acid with a redox system of Ce(IV) and organic reducing agents containing hydroxy groups were studied. The reducing compounds were poly(ethylene glycol)s, halogen-containing polyols, and depolymerization products of poly(ethylene terephthalate). Copolymers of poly(ethylene glycol)s-b-polyacrylonitrile, poly(ethylene glycol)s-b-poly(acrylonitrile-co-vinyl acetate), poly(ethylene glycol)s-b-polyacrylamide, poly(ethylene glycol)s-b-poly(acrylamide-co-vinyl acetate), poly(1-chloromethyl ethylene glycol)-b poly (acrylonitrile-co-vinyl acetate), and bis [poly(ethylene glycol terephthalate)]-b-poly(acrylonitrile-co-vinyl acetate) were produced. The yield of acrylamide polymerization and the molecular weight of the copolymer increased considerably if about 4% vinyl acetate was added into the acrylamide monomer. However, the molecular weight of the copolymer was decreased when 4% vinyl acetate was added into the acrylonitrile monomer. Physical properties such as solubility, water absorption, resistance to UV light, and viscosities of the copolymers were studied and their possible uses are discussed. (C) 1999 John Wiley & Sons, Inc.