Toward Reprocessable High-Performance Elastomer: Self-Assembly, Dynamic Covalent Chemistry, and Tailorable Properties

The development of elastomers that combine high performance with reprocessability is essential to meet extreme operational demands while addressing sustainability challenges. Polyurethane elastomers, as a representative class of high-performance elastomers, derive their exceptional toughness, flexibility, and durability from precisely engineered microphase-separated structures formed by self-assembly. Advances in characterization methodologies and molecular design strategies have enabled the optimization of static, dynamic, and stimuli-responsive properties, broadening their application in emerging fields. At the same time, reprocessability is achieved through dynamic covalent chemistry, which allows topological rearrangement of crosslinked networks without loss of integrity. Covalent adaptable networks provide a theoretical framework to link molecular exchange mechanisms with macroscopic viscoelasticity, self-healing, and processing behavior. Recent studies demonstrate that incorporating dynamic covalent chemistry into polyurethane elastomers and related elastomer systems enables closed-loop recycling and sustainable nanocomposite design while retaining mechanical robustness. This review highlights integrated strategies that bridge microphase engineering and dynamic network chemistry, and discusses opportunities and challenges in advancing high-performance, recyclable elastomers toward practical deployment.