Effect of different crystals of nano-TiO_2 on performances of finished cotton fabric

Aqueous dispersion of rutile and anatase TiO2 and corresponding poly(butyl acrylate) composite latexes thereof were used to finish cotton fabrics.The aging resistance,ultraviolet resistance and sterilization properties of the finished cotton fabrics under UV-irradiation were measured in order to investigate the response mechanisms of different crystal TiO2 particles to UV-irradiation and their effects on the performances of finished cotton fabrics.It was found that both of the crystals have good ultraviolet resistance,however,rutile TiO2 finished cotton fabric exhibits outstanding aging resistance but weak sterilization properties because of its absorption and diffuse scattering of UV light,while anatase TiO2 finished cotton fabric offers excellent sterilization but accelerates the aging process due to its strong photocatalytic effect which induces many strong oxidizing free radicals under UV-irradiation,that effectively inactivate bacteria and simultaneously accelerate the breakdown of the molecular chain of fibers.Thus,it is required to select the proper crystal of TiO2 for functional finish of fabrics,taking necessary measures to suppress the side effects.