High sunlight resistant thermochromic smart textiles based on UV absorbing polymer

Abstract In this study, a new UV absorptive copolymer was prepared and further applied in thermochromic smart textiles in order to improve its application property. Firstly, UV absorptive copolymer was prepared by solution polymerization using a structural monomer (methyl methacrylate, MMA) and a UV absorptive functional monomer (2‐[3‐(2H‐benzotriazol‐2‐yl)‐4‐hydroxyphenyl] ethyl methacrylate, BHEM), which absorbs UV light effectively and has strong absorption at 230, 305, and 340 nm. And then, a light‐resistant thermochromic fabric with a three‐layer structure was prepared via coating technology. The influencing factors on light‐resistant thermochromic fabrics were systematically investigated by controlling polymerization components and copolymer dosage. The fading rate of the optimized light‐resistant thermochromic fabric after 10 h illumination is only 27.9%, which is 60.9% improvement than thermochromic fabric without a protective copolymer. Light‐resistant thermochromic fabrics with a 36 μm UV absorbing polymer coating shows excellent color fastness, including wash fastness (five grades), wet rubbing fastness (five grades), and light fastness (two grades). Moreover, light‐resistant thermochromic fabrics have good color reversibility and fatigue resistance (100 cycles) properties. And this approach provides a feasible optimization scheme for improving the light resistance of thermochromic textiles.