Production of UV-protective cotton fabric by surface polymerization

Abstract

2-Hydroxy-4-acryloyloxybenzophenone (HAB) was synthesized and polymerized through admicellar polymerization on a cotton fabric in order to prepare the UV-protective fabric. Surfactant adsorption on cotton fabric and adsolubilization of the monomer in the admicelle were studied. The poly(HAB) formed on the fabric significantly reduced ultraviolet transmission through the fabric resulting in a modified fabric with excellent ultraviolet protection. For further improvement in ultraviolet protection with broad spectral coverage, another monomer with complimentary ultraviolet absorbing moieties, 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl methacrylate (BEM) was copolymerized with HAB through admicellar polymerization. Copolymer composition and monomer reactivity ratio were investigated. Moreover, two-functional cotton fabric was produced by double coating via admicellar polymerization. HAB was first coated to improve ultraviolet protection and then methacryloxymethyltrimethylsilane (MSi) was coated to create a hydrophobic surface. The treated fabric was found to have very good ultraviolet protection together with high water repellency. Besides admicellar polymerization method, vinyltriethoxysilane was used to modify cotton surface to provide polymerizable vinyl groups on the fiber surface, which was polymerized with BEM. With a suitable process and the use of silane coupling agent, poly(BEM) was successfully coated on the fabric with good uniformity and good resistance to washing resulting in a cotton fabric with excellent UV-protection property.