Fluoride‐Free Adhesives for Low Surface Energy Fluorinated Substrates

Abstract Designing high‐performance adhesives for fluorinated substrates, such as polytetrafluoroethylene (PTFE), remains a persistent challenge due to their ultra‐low surface energy and chemical inertness. Traditionally, strong adhesion to these surfaces has relied on fluorinated additives and per‐ and polyfluoroalkyl substances (PFAS), raising serious environmental and health concerns due to their persistence and toxicity. In response to increasing regulatory scrutiny and the rising demand for sustainable materials, a universal, fluoride‐free adhesive strategy based on copolymers featuring tertiary amine and amide functionalities is introduced. By leveraging strong dipole–dipole interactions afforded by carefully selected polar monomers, robust interfacial adhesion is achieved without the use of fluorinated components. The optimized copolymers, synthesized from 2‐(diisopropylamino)ethyl methacrylate and N,N‐dimethylacrylamide, demonstrate a record lap shear strength of 4.91 MPa on PTFE, significantly surpassing both commercial adhesives and previously reported systems. This work not only establishes a versatile and effective platform for fluoride‐free adhesion to challenging substrates but also advances the field toward next‐generation, environmentally responsible adhesive technologies.