Fabrication and performance of self-healing ONR composites via a CNFs/LA synergistic reinforcement strategy

Rubber-based functional materials frequently exhibit deficiencies in mechanical strength, tensile properties, self-healing efficiency, and sensing capabilities. This study employed oxidized natural rubber (ONR) as a matrix, integrating lipoic acid (LA) and cellulose nanofibers (CNFs) to establish a dynamic cross-linked network characterized by dynamic disulfide bonds and multiple hydrogen bonds. Coating the surface with ONR/LA/CNFs/CNT to create a conductive layer enables the detection of both minor and significant deformations. A flexible strain sensor was developed, demonstrating precise detection capabilities for various deformations, a high elongation at break of 419.58 %, moderate tensile strength of 1.72 MPa, and a gauge factor (GF) of 17.07.The sensor displays structural stability and responsiveness, along with a self-repair rate of 95.93 % within 0.5 h at 80 ℃, thereby ensuring durability and reliability. It effectively monitors human movement signals, presenting a promising solution for sustainable and repairable smart wearable devices.