Rational design of cotton substrates with enhanced UV-blocking, high antibacterial efficiency and prominent hydrophobicity

In this study, cotton fabrics with improved antibacterial efficiency and hydrophobic properties were prepared with the coatings of N-halamine siloxanes, ZnO, and silane precursors by the ultrasonic-assisted dipping-padding assembly technique. The coated cotton fabrics were characterized by FT-IR, SEM, XRD and XPS. The chlorinated cotton fabrics showed good hydrophobicity with water contact angle of 139(o)2(o). With the addition of ZnO in the N-halamine coatings, the chlorinated samples showed good antibacterial efficacy and could inactivate both all inoculated Escherichia coli O157:H7 (ATCC 43895) and Staphylococcus aureus (ATCC 6538) within 10min. The chlorinated samples also showed good viability to mammalian cells. The stabilities of the coated cotton towards UV light and washing cycles and mechanical properties were investigated. Over 69% of the chlorine was retained after the equivalent of 25 machine washes. The N-halamine siloxanes coating of cotton with ZnO nanoparticles significantly enhanced the UV stability. In addition, the coated cotton fabrics maintained high tensile strength and fair air permeability. [GRAPHICS]