Dual light and temperature responsive cotton fabric functionalized with a surface-grafted spiropyran-NIPAAm-hydrogel

A dual-responsive cotton fabric functionalized with a spiropyran-NIPAAm hydrogel, capable of dimensional changes upon irradiation with visible light or upon a temperature stimulus is reported. These volume changes are due to absorption and release of water, from and into the air, by increasing temperature above the LCST in the dark, and/or by irradiation with sunlight or white light from artificial sources. The material was obtained via grafting photo- and temperature-responsive monomers directly from the cotton fibers, using a facile controlled polymerization method, ARGET ATRP.