Sea-cucumber-inspired bio-based polyurethane with desirable stretchability, recyclability, and self-healing capabilities

The widespread adoption of polyurethane (PU) materials in adhesives and ultraviolet (UV)-resistant applications is limited by the challenge of balancing stretchability, recyclability, and self-healing capabilities, which requires an advanced molecular structural design. Here, we synthesize a castor-oil-based PU (COPUSD) that integrates disulfide bonds and multiple hydrogen bonds, drawing inspiration from the remarkable self-healing capabilities and stretchability of sea cucumbers. This biomimetic approach facilitates the development of a multifunctional PU material with excellent self-healing properties, tunable stretchability, and recyclable processing characteristics. The resulting PUs are employed as adhesion and anti-UV radiation materials and exhibit excellent adhesion properties. The transmittance of the PU is close to 0% in the range of 200–400 nm, indicating a strong blocking ability against UV. This study presents a pioneering approach for developing versatile and scalable PU materials that combine adjustable self-healing capabilities and efficient recyclability for adhesive and UV-resistant applications.