Structure of copolymers from polymerization of ethylene of polyvinyl acetate

Abstract

AbstractThe formation of “grafted” vinyl copolymers by polymerizing one monomer in the presence of a preformed vinyl polymer has been extended to a new monomer‐polymer combination and one point of attachment of the lateral (grafted) polymer chain has been shown precisely. When ethylene was polymerized in the presence of polyvinyl acetate under a variety of conditions, modified polyvinyl acetates having lateral polyethylene chains were formed. Alkaline methanolysis of such modified polymers yielded mixtures of long‐chain fatty acids and ethylene‐modified polyvinyl alcohols (which were inseparable from any unmodified polyvinyl alcohol that may have been present). The hydrolysis to long‐chain acids shows that polyvinyl acetate acts as a chain transfer agent and that one point of lateral growth of polyethylene chains is the CH3 in the acetoxy group of polyvinyl acetate. The second hydrolysis product, the ethylene‐modified polyvinyl alcohol, shows that chain transfer, and subsequent growth of polyethylene chains, can also occur on the chain carbons of polyvinyl acetate. Oxidation of the ethylene‐modified polyvinyl alcohols yielded a mixture of oxalic acid and long‐chain fatty acids. At the low ethylene pressures studied (300 to 1200 p.s.i.) only traces to small amounts of low molecular weight polyethylene waxes were formed.