Synthesis of block copolymers via redox polymerization

Polymerization and copolymerization of vinyl monomers such as acrylamide, a crylonitrile, vinyl acetate, and acrylic acid with a redox system of Ce(IV) and organic reducing agents containing hydroxy groups were studied. The re ducing compounds were poly(ethylene glycol)s, halogen-containing polyols, a nd 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, p oly(ethylene glycol)s-b-poly(acrylamide-co-vinyl acetate), poly(1-chloromet hyl ethylene glycol)-b poly (acrylonitrile-co-vinyl acetate), and bis [poly (ethylene glycol terephthalate)]-b-poly(acrylonitrile-co-vinyl acetate) wer e produced. The yield of acrylamide polymerization and the molecular weight of the copolymer increased considerably if about 4% vinyl acetate was adde d into the acrylamide monomer. However, the molecular weight of the copolym er was decreased when 4% vinyl acetate was added into the acrylonitrile mon omer. Physical properties such as solubility, water absorption, resistance to UV light, and viscosities of the copolymers were studied and their possi ble uses are discussed. (C) 1999 John Wiley & Sons, Inc.