Radiation grafting of various water-soluble monomers on ultra-high molecular weight polyethylene powder: Part I. Grafting conditions and grafting yield

Monomers of some water-soluble polymers; acrylic acid, methacrylic acid, ac rylamide, N, N-dimethyl acrylamide and 1-vinyl-2 pyrrolidone, were grafted on ultra-high molecular weight polyethylene (UHMWPE) powders by a direct gr afting method in an aqueous medium in air. Inhibition of homopolymerisation was achieved by adding various concentrations of Fe2+ or Cu2+ ions. It was found that the degree of grafting increases linearly with dose till a gela tion state is reached, and varies between 40 and 12% depending on the monom er. Four million molecular weight UHMWPE gave a higher per cent grafting th an a 6 million counterpart for the monomers used, with the exception of acr ylic acid monomer grafting. (C) 2001 Elsevier Science Ltd. All rights reser ved.