| 초록 |
In recent years, the development of controlled/living radical polymerizations (ATRP, NMP, RAFT) has expanded the way for macromolecular engineering, and various well-defined polymers with diverse compositions and topologies have been successfully synthesized. In the case of ATRP, selection of initiator, ligand, solvent, temperature etc. is the key issue to get well-defined polymers. As for RAFT, careful selection of the RAFT agent is crucial. In this talk, I will discuss the possibility to synthesize new architectural polymers by controlling the kinetics of the polymerization process. (1) When AB* monomers with the same initiating reactivity of B* and the formed A* are polymerized under ATRP conditions, hyper-branched polymers are usually obtained. If an AB* inimer is copolymerized with large amount of another active monomer by ATRP at low temperature through the initiation by B*, and at this temperature, the formed A* is activated very slowly, it can be supposed that the formed polymer structure will be quite different. (2) MAn and St can be copolymerized by RAFT to get well-defined reactive copolymers with predominant alternating structure; the polymerization is much much faster than the homopolymerization of St under similar conditions. Therefore, facile synthesis of multiblock copolymers based on MAn and St through RAFT copolymerization is possible. This can be done very easily by using different feed ratio of St to MAn, followed by the addition of MAn during the polymerization process. |
