Temperature-Sensitive Hydrogels

Synonyms

Thermosensitive hydrogels; Thermally-sensitive hydrogels; Intelligent gels

Definition

Temperature-sensitive hydrogels, which are part of  the family of stimulus-sensitive hydrogels, consist of water-filled polymer networks (i. e., gels) that display a temperature-dependent degree of swelling. Temperature-sensitive hydrogels are of interest to microactuation purposes for a number of reasons [1]: their volumetric size changes are large compared to other microactuation principles, hydrogels are soft and resilient, temperature-sensitive hydrogel actuators are operated at conveniently low temperatures and the hydrogel polymer networks can be microfabricated using standard photolithography.

Temperature-sensitive hydrogels can either display a positive temperature response, meaning that the gel material swells with increasing temperature, or a negative temperature response, meaning that the gel material shrinks with increasing temperature.

Chemical and Physical Principles

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