Facile Fluorine-free Finishing for Excellent Water Repellency of Cotton Fabric and Optimization Using Response Surface Methodology

Cotton fabrics are popular for their excellent properties, but their wider application is always limited due to their disadvantages including lack of water repellency and easy pollution. In this paper, based on improving environmental protection and the durability of water repellent, an organic-inorganic nano-hybrid cross-linked polysiloxane was prepared by chemical compounding method and emulsified to get water repellent. The water repellent finishing of cotton fabrics was carried out using the pad-dry-cure process, and the effect of finishing conditions on the water contact angle (WCA) of fabrics was investigated. Furthermore, the finishing process was optimized by the central composite design (CCD)-response surface method (RSM). The results show that the significant order of factors affecting the WCA of cotton fabric finished is successively finishing agent concentration > curing temperature > curing time. The established model has high prediction accuracy and the best finishing conditions are finishing concentration 89 g/L, curing temperature 162°C, curing time 130 s, response prediction value Y = 149.5°, which is very close to the experimental value of 149.7 ± 0.5°.