Abstract
Recent developments in the synthesis of stimuli-responsive polymers are reviewed. The progress has been faciliated predominantly by the discovery of living radical polymerization systems. As a typical example, the synthesis of thermo-responsive poly (N-isopropylacrylamide) and its block copolymers by living radical polymerization is demonstrated. Fast living cationic polymerization of vinyl ethers using SnCl4 or FeCl3 in the presence of an added base has also been investigated. The polymerization rate increased by 3 to 5 orders of magnitude relative to that using an EtAlCl2 initiating system. Especially, the use of a weaker base permitted ultrafast polymerization within 1-3 sec to give a polymer with a very narrow MWD. A new series of stimuli-responsive polymers, including block copolymers, gradient copolymers, and star-shaped polymers, were prepared by the living cationic polymerization. The stimuli-induced self-association of various block copolymers was also demonstrated.
