Anti-pilling of Cashmere Knitted Fabric Based on Siloxane-Modified Chitosan

In this study, chitosan was modified by two kinds of different siloxanes, gamma-glycidoxypropyl-trimethoxysilane (GPTMS) and gamma-glycidoxypropyl-dimethoxy- methylsilane (GPDMS), respectively, then applied for anti-pilling of cashmere knitted fabrics. The structure of the modified chitosan, the apparent morphology and the mechanical properties of the modified film were analyzed by FTIR, SEM and DMA, respectively. The hydrophilicity and swelling properties of the modified film were compared. The results showed that epoxy groups of siloxane reacted with amino groups of chitosan, and the -OR (R represents alkyl) groups of siloxane hydrolyzed and polycondensation conducted during the film-forming process. After modification, the mechanical properties of the film were more flexible, the hydrophilicity and swelling of the film was decreased. Cashmere knitted fabric was treated with the modified chitosan and glutathione was chosen as the model compound to explore the reaction between modified chitosan and cashmere fibers. The apparent morphology and elements distribution of the fibers were observed by SEM and EDS, respectively. The directional friction effect of the fibers was tested by fiber friction coefficient tester. The pilling grade, handle, whiteness and launderability of fabric were investigated. The results showed that the epoxy groups remaining in siloxane were reacted with the amino groups of cashmere fiber, which enhance the binding of the fiber and siloxane-modified chitosan, the siloxane-modified chitosan film formed on fibers in situ. The directional friction effect of the fiber significantly reduced, the tendency of fuzzes to the surface of the fabric was weakened and the probability of tangling of exposed fuzzings was reduced, the pilling grade of the fabric treated by modified chitosan reached level 4 and the fabrics had good launderability, the soft and smooth handle was still preserved. There was no obvious color difference of cashmere fabrics treated with siloxane-modified chitosan.