Study On Graft Copolymerization Of Natural Macromolecules Initiated By Cu(Ⅲ)

This paper is mainly about the study on the graft copolymerization of natural macromolecules redox-initiated with super valence trans-metal Cu(III) and will be discussed in two sections. Chapter I: The present research situation of Cu(III) and development as well as the present study on graft copolymerization of natural macromolecules such as chitosan, sodium alginate and gelatin were reviewed systematically. In addition, the theoretical and practical significance of Cu(III)'s application in graft copolymerization of vinyl monomers onto natural macromolecules were pointed out. Chapter II: Cu(III), paired with characteristic groups with reducibility on the macromolecules'backbones was used to initiate the graft copolymerization of acrylate monomers onto chitosan, sodium alginate and gelatin. High grafting parameters were obtained. The dependence of grafting parameters on such reaction conditions as temperature, reaction time, initiator concentration and the amount of monomer were also investigated. The resultant graft copolymers were characterized through FTIR, SEM, X-ray diffraction, and TGA. Furthermore, a tentative mechanism involving a single-electron-transfer process in reduction of Cu(III)→Cu(II) is proposed to explain the generation of radicals and the initiation. The copolymers of chitosan-g-PMMA were used as compatibilizer in blends of chitosan and terpolyamide. The SEM photographs illustrate that the addition of graft copolymer efficiently improved the miscibility of the blends.