Rational design of sustainable diblock copolymers toward strong adhesives and stretchable ionic conductive materials

Sustainable diblock copolymers of poly (isobornyl acrylate)-block-poly (methyl acrylate) (PIBOA-b-PMA) were rationally designed and synthesized with terpenoid-derived monomer IBOA as the rigid segment. These PIBOA-b-PMA diblock copolymers show excellent mechanical performance comparable to traditional triblock copolymer elastomers. They can be successfully utilized as strong sustainable adhesives with good adhesion performance and high adhesive strength. Moreover, stretchable liquid-free ionic conductive materials can be successfully fabricated by incorporating lithium bis(trifluoromethane sulfonyl) imide (LiTFSI) into PIBOA-b-PMA diblock copolymers without leakage or evaporation risks. Intriguingly, these ionic conductive materials show decreased tensile strength compared to that of pristine PIBOA-b-PMA diblock copolymer due to the plasticizing effect while still maintaining excellent extensibility. The resultant stretchable ionic conductive materials show accurate and dramatic resistance change in response to intermittent stretching-retraction deformations, finger joint bending/straightening curvatures, and elbow joint bending/straightening movements, demonstrating exceptional performance. This convenient and facile strategy can offer new opportunities for the development of novel bio-based diblock copolymers toward strong adhesives and stretchable ionic conductive materials.