A Highly Transparent, Self-Healing, and Durable Anti-Fogging Coating for Extreme Environments

Condensation of water vapor into discrete droplets on the surface of transparent optical devices-commonly known as fogging-severely degrades their optical performance. To address this issue, a highly transparent, self-healing, and durable polymer-based anti-fogging coating was developed via a facile one-pot copolymerization of 2-acrylamido-2-methylpropanesulfonic acid (AMPS), acrylic acid (AA), and vinyltrimethoxysilane (VTMOS). The chemical structure and composition were thoroughly characterized. The introduction of VTMOS constructs a hydrophilic-hydrophobic microphase structure through in situ formation of a Si–O–Si network, which significantly enhances the mechanical stability and water resistance. The polymer coating can maintain high transparency (>90%) under extreme conditions (85 °C steam and −40 °C freezing), exhibits long-term anti-frosting performance for 180 days, and demonstrates rapid water-assisted self-healing within 30 s. Differential scanning calorimetry (DSC) analysis reveals that each polymer unit binds approximately seven water molecules, elucidating the mechanism behind its exceptional anti-frosting capability. This work presents a practical strategy for designing high-performance, long-lasting anti-fogging coatings suitable for extreme environment applications.