A Transparent, Abrasion-Resistant Anti-Fog Coating on Glass Substrates

Abstract

The formation of fog on the surface of transparent glass severely reduces its transmittance, which limits its application in medical devices, optical instruments, and other industries that require high transmittance. A new transparent, water-resistant, and abrasion-resistant PVA anti-fog coating based on polyvinyl alcohol (PVA), 5-sulfosalicylic acid (SAD), and ammonium persulfate (APS) was developed in this study. The hydroxyl, carboxyl, and sulfonic acid groups in the SAD molecule can form dense hydrogen bonds with the hydroxyl groups on the PVA side chain, which increases the water resistance of the coating. APS, as a free radical initiator, can produce sulfate radicals during the thermal curing of the coating and eventually form a cross-linked structure of the PVA main carbon chain, thereby further improving the water resistance, friction resistance, and thermal stability of the coating. The experimental results show that the transparent glass surface modified by the coating not only has excellent light transmittance and anti-fog performance but also has good abrasion resistance and thermal stability. In addition, the preparation method of the transparent hydrophilic anti-fog coating is simple and convenient, and nontoxic and environmentally friendly water is used as the solvent, which is expected to be used in large-scale industrial production.