Cationic Gelatin Graft Copolymers: Synthesis, Characterization and Application

A novel cationic gelatin graft copolymer was developed by the graft copolymerization reaction of gelatin with acrylamide (AM) and methacryloyloxyethyl trimethylammonium chloride (DMC) in this paper. The structure of graft copolymer was analyzed briefly by the analysis of infrared spectrum, and it was found that monomers (AM and DMC) actually were grafted onto the backbone of gelatin. The effect of reaction conditions such as the weight ratios of AM/gelatin or AM/DMC on grafting parameters and the application of the cationic graft copolymer as the dry strength agent in papermaking were investigated. Experiments showed that a graft copolymer with high the percent grafting and the grafting efficiency could be obtained by controlling the AM/gelatin weight ratio and AM/DMC weight ratio. The application test showed that the results obtained from the physical intensities of handsheets under the treatment of the grafted gelatin [gel-g-P(AM-co-DMC)] were great better than the control sample, which was due to the hydrogen bonds and ionic bonds among fibres in pulp and cationic graft copolymer.