Recyclable Conductive Composite Adhesives with Balanced Adhesion and Conductivity

Abstract

Natural materials with hierarchical architectures, such as spider silk, integrate strength, toughness, and environmental adaptability within a single framework. Inspired by this multifunctionality, we report a waterborne polyacrylate emulsion platform for constructing recyclable covalent adaptable networks (CANs) through dual dynamic covalent cross-linking. Methyl methacrylate (MMA) and butyl acrylate (BA) serve as hard and soft segments, while acetoacetoxyethyl methacrylate (AAEM) provides reactive sites for network formation. The network incorporates Schiff-base linkages and disulfide bonds and exhibits thermally activated stress relaxation and hot-press reprocessability. By tuning the MMA/BA ratio and AAEM content, the network structure and mechanical properties are programmable. The optimized SS-POM6.5B3.5-3 film exhibits a Young’s modulus of 116 MPa, an elongation at break of 365%, and a gel content of ≈94%. It also functions as an adhesive and a reprocessable matrix for conductive carbon nanotube (CNT) composites. This bioinspired waterborne acrylic platform integrates tunable mechanics, substrate-dependent adhesion, thermal reprocessability, and conductive functionality for multifunctional adhesive applications.