| The thesis consists of two parts: 1. Degenerative transfer polymerization of vinyl acetate in the presence of iodine using AIBN as an initiator; 2.Synthesis of PVAc-b-PMMA block copolymersControlled/"Living" radical polymerization of vinyl acetate was achieved by a DT process with I2 using AIBN as an initiator. After an induced period, the polymerization went smoothly. The conversion increases with the time and molecular weights of the polymers increase linearly with the conversions. The molecular weight distributions keep low (Mw/Mn<1.5). 1H NMR spectrum for the reaction solution of I2 with AIBN, I2 with VAc and the polymerization system of VAc/AIBN/ I2 was measured respectively. The results indicated that I2 reacted with AIBN to give the corresponding iodide (CH3)2(CN)C-I and I2 reacted with VAc to give α - iodoethylacetate, which were both supposed to act as transfer agents. End-groups of the polyvinyl acetate were analyzed by 1H NMR indicating that the iodo-terminated chain ends were unstable and decomposed to aldehyde groups.The copolymer of PVAc-b-MMA was synthesized with two methods. The first one employed PVAc bearing iodo-end groups as micro-transfer agent, in the presence of AIBN, methyl methacrylate was polymerized; In the second method, the polymerizationof MMA was conducted with PVAc -I as a macroinitiator catalyzed by CuCl/PMDETA, CuCl/MA5-EDTA and FeCl2·4H2O/PPh3.The polydispersities of the block copolymers were narrow. Also the molecular weights and structures of synthesized PVAc-b-MMA were characterized by GPC and 1H NMR and shown that the block copolymers were novel.
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