Transparent Grafted Zwitterionic Copolymer Coatings That Exhibit Both Antifogging and Self-Cleaning Properties

In this work, we have investigated a zwitterionic copolymer that demonstrates outstanding antifogging and self-cleaning properties. These polymer coatings are photochemically grafted to substrates containing C-H bonds with rapid kinetics and form a robust polymer networks on plastic and alkyl-modified glass surfaces. The copolymers consist of a zwitterionic monomer, which provides high hydrophilicity, and a benzophenone moiety that produces a densely cross-linked network. The optical clarity of the substrates is not impacted by the polymer coating and even slightly improved due to the lower refractive index of the polymer relative to glass. The antifogging and self-cleaning capabilities were determined by a series of experiments, where the optical transmittance of substrates modified with copolymer coatings was excellent under both hot and cold fogging conditions. Additionally, surfaces contaminated with oil are easily cleaned by simply submerging the coatings in water. Moreover, the coatings exhibit excellent chemical and mechanical resistance and maintain antifogging properties after abrasion testing in the presence of either chemical detergents or common household cleaners.