Facile fabrication, properties and application of novel thermo-responsive hydrogel

The authors report a novel thermo-responsive hydrogel design based on the thermally induced aggregation of two kinds of nonionic surfactants: triblock copolymer poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (EPE) and 4-octylphenol polyethoxylate (TX-100). In the preparation of the hydrogel, agarose is used to host the aqueous surfactant molecules, allowing them to move freely through its intrinsic network structure. To study it, EPE molecules are labeled with fluorescent Rhodamine B, and the aggregation phenomenon under various temperatures is imaged by fluorescence microscopy. In order to realize flexible control of the opaque/transparent transition temperature (OTTT), the surfactants' aggregation is modified by adding ionic surfactant or salts. The rate of the opaque/transparent transition and applications in the smart window and smart roof based on this kinds of hydrogel are also investigated.