GRAFT COPOLYMERIZATION OF ACRYLAMIDE ON VARIOUS CELLULOSIC MATERIALS USING CERIC ION AND METAPERIODATE AS INITIATORS

Abstract

Graft copolymerization of acryiamide onto various cellulosic materials in an aqueous medium was carried out by using ceric salt and metaperiodate as initiators, and the grafting site was studied.The per cent grafting increased with increasing content of carbonyl groups or with decreasing content of carboxyl groups in the samples by using ceric salt as an initiator. Apparent activation energy calculated from the initial rate of graft copolymerization onto dialdehyde cellulose was approximately 10.1kcal/mol. These results indicate the possibility that the graft copolymerization is initiated by the redox reaction between cericion and hydroxyl groups.The per cent grafting and the apparent number of grafted chains on acid hydrolyzed samples are larger than those on methanolyzed one. By the addition of butyl aldehyde to polymerizing medium the polymerization of acryl amide was initiated in the absence of ceric salt, but the grafting did not occur. In the presence of periodate initiator, the polymerization of acrylamide increased with the increasing pH of the system, but the grafting was not remarkable. This indicates that the grafting starts more easily from the end than the carbonyl or hydroxyl group of cellulose molecule.Graft copolymerization onto cellulose derivatives V.