| RAFT polymerization method combines the advantages of free radical polymerization and living polymerization, it can be carried out in bulk, solution, suspension and also emulsion. On the same time, polymers with targeted structures can be synthesized through this method. In addition, its polymerization conditions are similar to those of traditional free radical polymerization and a wide range of monomers can be used in RAFT polymerization. Therefore, RAFT has bright future for application and attracts the attention of many polymer researchers. As we know, RAFT polymerization technology has improved a lot since it is invented several years ago. However, there are still some key problems existing in RAFT technology, ie: the explanation of retardation in the polymerization process: how to make the RAFT emulsion polymerization more effective; the prerequisite of solving these problems is to find suitable RAFT agent, which is also the most important consolation to carry out effective RAFT polymerization. Usually, dithioester is a very effective chain transfer agent, and its behavior in RAFT polymerization is determined by the structure of its R group and Z group.The work in this thesis can be summarized as the following: (1). To change the structure of Z group in dithioester, and find effective RAFT agent. Also investigate the influence of the structure of RAFT agent on polymerization to give useful clues for finding more effective RAFT agent; (2). To find out certain RAFT agent which is easy to synthesize and purify, and investigate the controllability of free radical polymerization when using this RAFT agent in common monomers; (3). Introduce microwave irradiation (MI)technology into RAFT polymerization to reduce 'Retardation' in RAFT polymerization, to increase polymerization rate and providing possible way for the further industrialization of RAFT technology; (4). Use functionalized initiator to introduce functional group to the polymer chain end, and provide a method of polymer molecular design; (5). Investigate the RAFT polymerization of long side-chain acrylate, synthesize polymers with narrow PDI and provide a convenient way to synthesize additives for petrol products.In summery, following conclusions were made: (1) RAFT polymerization of ODA, using AIBN as an initiator and CPDB (2-cyanoprop-2-yl dithiobenzoate) as a RAFT agent has been investigated. Results show controlled free radical characters. DSC (Differential Scanning Calorimetry) results show that PODA obtained from RAFT polymerization has a greater crystallinity than that polymerized from conventional free radical polymerization. (2) A dithioester with large conjugation structure, 2-cyanoprop-2-yl dithionaphthalenoate (CPDN), was employed in the controlled radical polymerization of Styrene (St) and Methyl Methacrylate (MMA). Both of these two monomer's polymerizations show "living'Vcontrolled polymerization characters. Retardation has been found in both of these two monomer's polymerization. (3) Consist with common RAFT agent are unstable dithioesters, we synthesized bis(dithionaphthoyl) disulfide (BTNDS), a stable and easy to purify compound. RAFT polymerization of Styrene was carried out successfully by using BTNDS and AIBN to synthesis RAFT agent in situ. Results show the "living'Vcontrolled nature of this polymerization system. The polymerization mechanism is assumed. "Living'VControIled free radical polymerization of methylacrylate (MA), butyl mathacrylate (MBA), Octanylacrylate (OA) and methyl methacrylate (MMA) were also successfully carried out. (4)A dithioester 2-cyanoprop-2-yl dithio-9-phenathrenoate (CPDPA), which contains larger conjugation structure in Z group than the one in CPDN has been synthesized. Using CPDPA as a RAFT agent and AIBN as an initiator, RAFT polymerization of MMA was carried out in bulk. The polymerization shows well controllability with an inhibition period at all experiments. The polymerizations do not show obvious retardation in the reaction system. (5) MMA has been polymerized under'living'/controlled ma...
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