Rosin-Modified Polyurethane Elastomers with Room-Temperature Self-Healing Ability, High Strength, and Recyclability Based on Oxime Dynamic Bonds

Rosin, with a rigid hydrogenated phenanthrene ring, is a widely available biomass, but its high-value utilization needs to be enhanced. Inspired by sustainable development strategies, the design of polymer elastomers with a room-temperature self-healing capability has been a hot focus topic. However, designing elastomers that combine the conflicting properties of high mechanical performance and room-temperature self-healing is a significant challenge. The hydrogenated phenanthrene ring of rosin provides a superior solution to this problem. In this work, the polyurethane elastomer (BPU-X% AP) based on rosin-hydrogenated phenanthrene ring structure, dynamic oxime, and hydrogen bonding was reported. The BPU-X% AP exhibits high tensile strength (37.8 MPa), and good toughness (126.9 MJ m–3). Due to the rosin structure that promotes the movement of the elastomer chain segments, the elastomers have fast room-temperature self-healing and recyclability. Benefiting from their excellent mechanical strength and self-healing properties, BPU-X% AP as adhesives exhibits a strong lap shear strength of 5.5 MPa, and they can be used as hot melt binders. Corresponding to the cycling of the elastomer, the adhesive strength of BPU-10% AP remains almost the same after three cycles of adhesion to the iron and aluminum plates. This work provides a viable approach for the preparation of high-performance biomodified polyurethanes.