Recyclable, freeze -resistant, harsh-environment capable self-healing bio-based polyurethane elastomers for self-powering intelligent transport systems

Abstract

Triboelectric nanogenerator-based self-powered transportation systems have the potential to be key components of future smart cities, contributing significantly to sustainable urban development and intelligent management. However, their durability and stability in challenging environments, such as low temperatures, remain unresolved. In this work, a bio-based monomer with a bis-alkane side-chain structure was introduced to develop a transparent, freeze-resistant, and reprocessable bio-based polyurethane elastomer (PLBEM). Notably, the elastomer demonstrated excellent self-healing properties under low temperatures (−30 °C), supercooled saline (−30 °C, 30 % NaCl), as well as strong acid and alkali conditions, with healing efficiency of 83 %, 80 %, 85 %, and 80 %, respectively. Experiments and molecular simulations showed that the excellent low-temperature self-healing properties of the elastomers were attributed to the bis-alkane side-chain structure that provided abundant van der Waals forces and self-plasticization for the materials. Additionally, the flexible triboelectric nanogenerator (LB-TENG), using PLBEM as the friction layer, achieved a 95 % voltage recovery rate after self-healing at −30 °C. The LB-TENG-based intelligent transportation system can not only power traffic signals but also alert drivers to prevent accidents from fatigue driving. Therefore, the all-weather, self-powered traffic monitoring system is expected to enhance safety and security for transportation.