Cotton and polyester surface modification by methacrylic silane and fluorinated alkoxysilane via sol-gel and UV-curing coupled process

The aim of the present work was the surface modification of cotton and polyester fibers to confer hydro and oil repellency to the fabrics. Sol-gel, previously investigated by the same authors as textile finishing, was here chosen as surface treatment not involving the bulk of the fibers, so fabrics can keep unvaried comfort characteristics. Moreover, it was coupled to post-UV-curing to enhance the finishing adhesion to fibers, improving treatment fastness. Process optimization was in fact focused on an economical and ecofriendly process to obtain an effective finishing with good fastness to washing. 3-(Trimethoxysilyl)propyl methacrylate (MEMO) was used as sol-gel precursor both alone and with Fluorolink® S10, a commercial product from Solvay Solexis (Italy), to obtain an UV-curable modified nanosol to be applied to fabrics with add-ons ranging from 5% to 30% o.w.f. (on weight of fibers). Treated samples were tested by means of contact angle measurements with water and oil while fastness to washing was tested according to ISO standard (till 5 washing cycles). Moreover the modifications that occurred on fiber surface were investigated by FTIR-ATR and XPS while the influence on thermal properties was revealed by DSC measurements. Promising results were obtained in terms of conferred water and oil repellency and treatment fastness, enhanced in particular on UV post-cured samples, as expected.