Enhancing adaptive performance of thermoresponsive ionogel systems through redundancy-driven architecture

Abstract

Flexible material systems are vital in humanoid robots and advanced medical devices, where the failure of a single component can jeopardize the entire system. To ensure system safety, it is crucial to strengthen weak points while maintaining core functions. In this context, we introduce the concept of redundancy design into flexible material systems, using thermoresponsive ionogel systems as a proof of concept. Covalent organic frameworks (COFs) or other porous materials, such as SBA-15 and halloysite nanotubes (HNTs), are incorporated into upper critical solution temperature (UCST)-type PNIPAm-based ionogels through nanoconfined polymerization. This integration yields ionogels with significantly improved mechanical properties: fracture energy is elevated by 170 times at room temperature and 18.2 times at elevated temperatures; toughness is improved by 17 times and 17.5 times; fracture strain is increased by 5.8 times and 1.9 times and stress is enhanced by 1.9 times and 6.2 times, all while maintaining their essential thermoresponsive characteristics. Additionally, these materials exhibit superior shape retention, self-healing capabilities, and strong adhesion to various substrates, underscoring their potential for diverse applications. These results implicated redundancy design can enhance the adaptability of flexible intelligent material systems through molecular-scale design, offering key insights for their extensive application scenarios.