2014 Volume 14 Issue 2 Pages 73-80
This review highlights the newly developed thermosensitive polymers exhibiting a sharp thermosensitive phase transition in water, as the representative stimuli-responsive polymers. Especially, recent precision synthesis via living polymerization has created new possibilities to a variety of stimuli-responsive polymers. Poly(N-isopropylacrylamide) [poly(NIPAM)] and a wide range of other thermoresponsive polyamides with well-defined structures have been synthesized by mainly living radical polymerization. Furthermore, various block copolymers were extensively synthesized and their characteristic thermosensitive behaviors and their applications to the biomedical fields were demonstrated. On the other hand, polymers with oxyethylene groups exhibited also a sharp thermosensitive phase transition in water. For example, a variety of thermosensitive poly(vinyl ether)s with controlled sequences and/or shapes such as various block copolymers and star-shaped polymers were designed and synthesized by living cationic polymerization. In addition to the selective synthesis, the thermosensitive behavior of polymers with oxyethylene groups is briefly reviewed. The recent progress in the investigations on thermosensitive poly(vinyl ether)s such as thermosensitive star polymers, stimuli-responsive alternating copolymers with quantitative degradability, and thermosensitive liposomes for tumor-specific chemotherapy, is also described in the last part.
