Chemical and water protective surface on cotton fabric by pad-knife-pad coating of WPU-PDMS-TMS

Surface functionalization of textiles is crucial in developing protective clothing that protects wearers from potential hazards of liquid, chemical and biological contamination. This study aims to explore chemical and water protective surface on cotton fabric by pad-knife-pad coating of waterborne polyurethane (WPU), polydimethylsiloxane (PDMS) and trimethylated silica (TMS). The chemical structure of the coated cotton fabrics was characterized by attenuated total reflectance Fourier transform infrared spectroscopy. Surface wettability and liquid protective properties of the coated cotton fabrics were analyzed by water contact angle, water repellency, hydrostatic pressure, and oil and aqueous liquid repellency. It was revealed that WPU and PDMS-TMS formed copolymerization reactions, resulting in ultrahydrophobic, oil repellent and mechanically strong membrane on the surface of cotton fabric. It has been found that the coating of WPU-PDMS-TMS makes cotton fabric highly resistant to water, oil and aqueous liquids. This surface functionalization technology can be further applied in developing protective clothing with chemical and water resistant and self-cleaning properties.