Fabrication and characterization of carbon nanotube/graphene/elastomer nanocomposites for stretchable conductor

Abstract

Stretchable conductor is the attractive material due to the conducting property under bending and stretching conditions. For these reasons stretchable conductor is able to operate on arbitrary curved shape. Thus, stretchable conductor can be applied to electronic artificial skin, skin patch sensor, wearable computer and stretchable display. Recently, numerous attempts such as mixing with nanofillers in stretchable matrix to improve the electrical properties of elastomers have been reported. CNTs and graphene are candidate materials as nanofillers because of good electrical properties, high aspect ratio and compatibility with stretchable elastomers. However, these conducting fillers are difficult to disperse in elastomer matrix, causing poor electrical properties and stretchability. To solve these problems, many researches have been conducted surface modification of conductive fillers to enhance the electrical properties of elastomers. Still, these methods have limitation to overcome degradation of quality of conductive fillers and remove residual functional group. In this work, we provide a method to enhance the dispersibility in PDMS elastomer by CNT-graphene hybrid system. This CNT-graphene hybrid system has advantages such as enhancement of electrical connection induced by CNT bridging between graphene sheets and improvement of dispersibility by spacing between conductive fillers CNT/graphene/PDMS stretchable conductors are prepared with various CNT-graphene ratios. Among the composites composed of other ratio, CNT/graphene (9:1)/PDMS nanocomposites show higher conductivity compared to other ratio of nanocomposites at 0.4 wt.% fillers. These results show probability to enhance performance of stretchable conductor by introducing CNT-graphene hybrid system.