Diblock-copolymer-coated water- and oil-repellent cotton fabrics

A diblock copolymer consisting of a sol-gel-forming block and a fluorinated block was used to coat cotton fabrics, yielding textiles that were highly oil- and water-repellent. The coating procedure was simple. At grafted polymer amounts of as low as 1.0 wt %, water, diodomethane, hexadecane, cooking oil, and pump oil all had contact angles surpassing 150° on the coated cotton fabrics and were readily rolled. The liquids were not drawn into the interfiber space by the coated fabrics. Rather, droplets of the nonvolatile liquids such as cooking oil retained their beaded shapes for months with minimal contact angle changes. When forced into water, the coated fabrics trapped an air or plastron layer and this plastron layer was stable for months. In addition, the coating had high stability against simulated washing, and the mechanical properties were essentially identical to those of uncoated cotton fabrics.