A Tough Silicone Coating with Self‐Healing, Reversible Adhesion and Recyclability Based on Reversible Anthracene Photodimerization

Silicone coatings suffer from critical limitations, including insufficient toughness, poor substrate adhesion, lack of self-healing capability, and non-recyclability. Herein, a novel photoresponsive silicone coating synergizing poly(dimethylsiloxane) (PDMS) flexibility with anthracene photodimerization chemistry is reported. By incorporating anthracene-functionalized diol monomers into a PDMS backbone, the resultant polyurethane network achieves dynamic covalent crosslinking via UV-triggered [4+4] cycloaddition and cleavage. Systematic investigations reveal that the optimized formulation exhibits exceptional mechanical toughness (elongation at break: 2540%), autonomous self-healing at 30 °C, and UV-switchable adhesion (>95% reversibility). The material's dual dynamic network-comprising hydrogen bonds and anthracene π-π interactions-enables solvent- or thermal-assisted reprocessing with >83% retention of initial mechanical/adhesive performance after 30 cycles. This work provides a paradigm for designing multifunctional coatings that integrate robustness, adaptability, and circularity, addressing sustainability challenges in aerospace, electronics, and medical devices.