Free Radical Polymerization Initiated By Initiator Containing Xanthone Structure

The first section of the thesis reported photo-initiated polymerization of acrylamide, XCA-K as water-soluble photo initiator. The results showed that the XCA-K and EDAB system can initiate the polymerization of acrylamide under UV light. The monomer conversion goes up with the increasing of reaction time and to as high as close to 100%. However the molecular weight decreases with the increasing of the reaction time. Temperature has little influence on the polymerization. The obtained PAM can be used as macroinitiator for the thermal polymerization of acrylamide in water solution.The second section of the thesis investigated the thermal polymerization of methyl methacrylate initiated by Bixan. The monomer conversion increases almost linearly with the reaction time with the polydispersitiy in the range of 1.5-2.0. The addition of a little amount of acrylic acid can promote the reaction significantly. Bixan fragments can be observed clearly from the ~1H NMR spectrum of obtained PMMA. Combinating the results of ~1H NMR,GPC and UV, it could be concluded that initiator fragments are bonded to the both end of the polymers. The obtained PMMA with initiator fragment could be used as macroinitiator to initiate a second monomer, styrene, to form block copolymer. It was observed that the monomer conversion and molecular weight increased with the reaction time. It seemed that the polymerization initiated by Bixan has some characters of "living" polymerization.