Flexible and Durable Fluorine-Free Antifouling Coatings of PDMS-Modified Block Polyurethane

This study tackles the drawbacks of existing antifouling coatings, including insufficient durability, cumbersome preparation procedures, and poor environmental compatibility. A room-temperature curable, fluorine-free, and solvent-free antifouling coating (KSPU-5-X) was successfully fabricated by grafting polydimethylsiloxane (PDMS) onto the polyurethane molecular backbone via a block modification strategy. The PDMS content (mole fraction: 5%–20%) was systematically regulated, and a silane coupling agent was incorporated to enhance the interfacial compatibility of the coating. Performance test results indicated that the as-prepared coating achieved a grade 0 adhesion rating, combined with excellent mechanical properties. It exhibited a surface energy ranging from 24.86 to 28.34 mJ/m 2 and demonstrated remarkable antiadhesion performance against contaminants such as coffee and ink. After 1,000 wear cycles, the coating retained stable liquid-repellent properties, along with favorable chemical corrosion resistance and thermal stability. Featuring a simple preparation process and outstanding environmental compatibility, this coating provides a feasible technical route for the practical application of high-performance antifouling coatings.