Biomass-Driven Composites with Integrated Hydrophobicity, mechanical Resilience, and enhanced conductivity for underwater sensing and adhesion

Abstract

Biomass-based conductive elastomers hold great promise for flexible electronics, yet simultaneously achieving superior mechanical performance, electrical conductivity, and water resistance remains a critical challenge, hindering their practical implementation. Herein, we present a simple and scalable method for fabricating biomass-derived conductive elastomers using α-lipoic acid as the primary structural building block, coupled with mild heating and UV irradiation. This dual-step process facilitates molecular reorganization and network optimization, yielding an elastomer with excellent mechanical resilience, sensing performance, and hydrophobic properties. The engineered elastomer exhibits a remarkable elongation at break of up to 700 % and maintains an elasticity recovery of 87 % under repeated large-strain cycles. Even in the presence of notches, it retains 72 % of its original elongation at break, demonstrating outstanding durability. Its unique molecular structure and hydrophobic properties afford strong adhesion to various solid substrates, with underwater adhesion strengths reaching up to 3.0 MPa, alongside remarkable stability in extreme pH and saline environments. Moreover, the elastomer exhibits excellent conductivity and dual-environment sensing capabilities, enabling precise and real-time detection of deformations, body motion, and temperature changes in both air and underwater conditions. This work opens new avenues for flexible electronics, soft robotics, and sensing technologies, particularly in underwater environments where durability, adaptability, and precision are critical.