Living Radical Polymerization With Iodide Formed In Situ

The thesis consists of four parts: Degenerative transfer polymerization (DT) of MA with iodide in situ as a transfer agent and AIBN/I₂/MA in situ initiated atom transfer radical polymerization (ATRP); DT polymerization of MMA in the presence of iodine or its derivative using AIBN as an initiator; Degenerative transfer polymerization of VAc in the presence of elemental iodine .1. Degenerative transfer radical polymerization (DT) of MA was achieved using iodide in situ as a transfer agent 2,2' -azobis(isobutyonitrile) (AIBN) as initiator. After several hours' induction period the conversion increase with time and the molecular weights of the polymers increased with conversion and the MWD of obtained polymers were relatively narrow (M_w/M_n<1.9). The influence of the concentration of I₂ and concentration of monomer . ¹HNMR spectrum for the I₂ with MA and the polymerization system of MA/AIBN/I₂ in 30/0.6/1.0 molar ratio at 75℃. The results indicated that I₂ reacted with AIBN to give the corresponding iodide (CH₃)₂(CN)C-I, which was supposed to act as a transfer agent. The end group of -CH=CCOOCH₃ indicated iodo-terminated chain was unstable and sensitive to moisture and light. It was suggested that all the polymerization reaction should performed in dark.2. MA/AIBN/I₂ system was used as the initiator in the ATRP of St. With. CuBr/MA₅-DETA and CuBr/PMDETA as catalyst, after a short induction period the system appeared first-order kinetics and MWD were relatively narrow. Different with the PMDETA was that MA5-DETA as ligand resulted slower polymerization rate and broader MWD, higher molecular. The effect of temperature and concentration of initiator to this system were studied ,we draw a conclusion that (CH₃)₂(CN)C-I not only was the initiator of ATRP, but also was the transfer agent of DT.We studied the block polymerization and extension chain polymerization, also analysis their kinetics and the effect of temperature on block polymerization.3. Degenerative transfer radical polymerization of MMA with iodide in situ as...