A robust and transparent hydrogel coating for sustainable antifogging with excellent self-cleaning and self-healing ability

Films with antifogging properties can be used in a wide range of fields, from manufacturing to agriculture, such as screens, camera lenses, and greenhouse films. In this study, a scraping technique was utilized to coat antifogging films on polyethylene substrate by using a solution containing polyvinyl alcohol, sodium alginate, and glycerin with suspended titanium dioxide nanoparticles. The resulting hydrophilic coating has outstanding antifogging, self-healing, and anti-fouling qualities due to the polymer’s great hydration capacity. The coating also held up well during prolonged heat and ultraviolet exposure (40 °C for 17 days and 192 h of 1.27 mW/cm2 UV radiation). Furthermore, when exposed to 30 g sands impact from a height of 10 to 40 cm, 18 days outdoors and 1 h soaking in polar and non-polar solvents (absolute ethanol, isopropanol, n-hexane and n-hexadecane), the hydrophilicity and antifogging performance were well sustained. Different flexible/rigid substrates, such as PET, PC, PVC, and others, can be successfully coated with antifogging film by using such simple construction approach.