Grafting vinyl monomers onto wool fibers. III. Graft copolymerization of methyl methacrylate onto wool using hexavalent chromium ion

The use of hexavalent chromium to initiate graft copolymerization of methyl methacrylate onto wool fibers has been investigated. The rate of grafting was determined by varying monomer, chromium(VI), temperature, acidity of the medium, nature of wool, reaction medium, and redox system. The graft yield increases with increasing monomer concentration up to 0.65M, and, with further increase of monomer the graft yield decreases. The graft yield increases with increasing chromium(VI) concentration. The grafting is considerably influenced by chemical modification of wool prior to grafting. The effect of certain inorganic salt and anionic surfactant on the rate of grafting has been investigated. The graft yield is influenced by thiourea concentration; it decreases with increasing thiourea concentration.