Thermoresponsive copolymers: from fundamental studies to applications

Thermoresponsive copolymers have attracted considerable interest in both the polymer and biomaterial literature. They show interesting fundamental behaviour (thermally triggered contraction and aggregation) as well as potentially useful properties (reversible gelation). Biocompatible thermoresponsive copolymers are being developed for application in drug delivery and regenerative medicine. This review focuses on the fundamental aspects of thermally triggered conformational changes with an emphasis on copolymer design. Also, the ability to use these copolymers to produce thermoresponsive colloidal dispersions is discussed. Recent examples from within our group and elsewhere are considered in order to illustrate structure–property relationships. The review focuses on copolymers involving N-isopropylacrylamide. However, non-acrylamide thermoresponsive copolymers are also considered in detail. Emerging areas that appear likely to be actively pursued in the future are also discussed.

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