Cellulose nanocomposite modified conductive self-healing hydrogel with enhanced mechanical property

Abstract

Synthetic conductive materials capable of self-healing have attracted increasing attention and have been developing rapidly because of their potential applications. Despite great achievements, there is a need to advance mechanical properties and reduce the time for healing simultaneously since the branch functionalities are limited and the polymer mobilities are poor in current devices. In this work, we report an effective and simple free radical polymerization approach to synthesize hydrogel using multi-vinyl-modified reduced graphene oxide (rGO) and acrylate monomers containing abundant polar groups. After enhanced by polar groups modified Cellulose Nanocrystal (CNC), the hydrogel exhibits extremely fast electronic self-healing ability and excellent repeatable restoration performance at 25 °C. The stress of hydrogel reaches 2.5 MPa and 1600% of elongation. The hydrogel recovers to its original mechanical and conductive properties within 12 s after cutting and maintains efficiency of nearly 99.3% of its original mechanical and conductive properties after 5 times of cutting and self-healing processes. The design of this conductive, room-temperature self-healing hydrogel takes unique advantage of supramolecular chemistry and polymer nanoscience and shed light on promising applications for self-healing electronics, artificial skins, soft robotics, biomimetic prostheses, and energy storage.