A Strong, Tough, and Self-Healing Strengthening Thioctic Acid-based Elastomer for Highly Reliable Flexible Strain Sensor

Abstract

Elastomers with high strength and toughness, excellent self-healing properties, and biocompatibility have broad application prospects in wearable electronics and other fields, but preparing it remains a challenge. In this work, we propose a highly adaptable strategy by introducing the small molecule crosslinking agent of triethanolamine (TEA) to the poly thioctic acid (PTA) chains and preparing the PA_xE_y elastomers using a simple synthesis step. This strategy stabilizes the PTA chains by constructing multiple non-covalent cross-linked dynamic networks, endowing materials with excellent strength and toughness (tensile strength of 288 kPa, toughness of 278.2 kJ/m³), admirable self-healing properties (self-healing efficiency of 121.6% within 7 h at 70 °C), and good biocompatibility. The PA_xE_y elastomers can also be combined with MWNTs to become flexible strain sensors, which can be used to monitor human joint movements with high sensitivity, repeatable responses, and stability.