Synthesis of UV-curable acrylate polymer containing sulfonic groups for anti-fog coatings

• We propose a new anti-fog coating system containing sulfonic acid group.
• The optimum coating formula with great anti-fog properties was given.
• The UV-cured coatings exhibit good mechanical properties and optical transparency.

A series of UV curable hydrophilic acrylate polymers containing sulfonic acid group was prepared via free radical copolymerization using 2-acrylamido-2-methyl propane sulfonic acid (AMPS) as hydrophilic monomer, which were used as prepolymers for anti-fog coatings. The expected structures were confirmed by FT-IR, 1H NMR and gel permeation chromatography (GPC). These UV-curable acrylate polymers were then mixed with reactive diluents and photoinitiator to form coating formulas. Various substrates were coated with these formulas and cured under UV exposure to obtain transparent coatings with good adhesion and hardness. The anti-fog properties of UV-cured coating were measured by contact angle test and anti-fog test. The results showed that the AMPS content in prepolymer had a great influence on the anti-fog properties of UV-cured coating. The formula was optimized and the corresponding UV-curing anti-fog coating was manufactured. The test results indicated that the coatings showed good mechanical properties, great optical transparency and excellent anti-fog performance.