A durable and multifunctional antifog, antifrost, and self-cleaning/oil repellant UV curable coating based on poly(sorbitol-co-isophorone-co-ethyleneglycol)acrylate

Sorbitol is a naturally occurring sugar alcohol and this work focuses on sorbitol-based UV curable polyurethane coatings for antifog, antifrost, and self-cleaning applications. The resins were synthesized by reacting isophorone diisocyanate (IPDI) with varying proportions of sorbitol and polyethylene glycol (PEG200). The resins synthesized were characterized by FTIR, ¹H NMR, and analytical techniques such as hydroxyl, iodine, and acid values. Various formulations were prepared using the developed resin, reactive diluents, and photoinitiator. The coatings were applied on silane-treated glass substrates and then cured under UV light. The hydrophilicity of coatings was investigated by water contact angle measurement. The antifog, antifrost, and self-cleaning tests were carried out and it was observed that the coating shows antifog property for a contact angle below 33° but antifrost effect was shown by the coatings with a contact angle less than 7°. Owing to the excellent hydrophilicity, the black stains of oil were washed out with ease under a water flow, hence showing excellent oil repellent/self-cleaning property as well.