Advances in Electrically and Thermally Conductive Functional Nanocomposites Based on Carbon Nanotubes

Abstract

The paper presents a review of CNTs synthesis methods and their application as a functional filler to obtain polymer composites for various technical purposes for strain gauges, electrical heating, anti-static coatings, electrically conductive compounds, etc. Various synthesis methods allow CNTs with different morphology and structural properties to be created, which expands the possibilities of the application of such nanoscale structures. Polymers can provide such effects as ‘shape memory’ and self-repair of mechanical defects. Different combinations of polymers and dispersed fillers influence the change in electrical and thermal conductivity, as well as the positive temperature coefficient of resistance, which makes it possible to achieve the effect of temperature self-regulation during electrical heating. CNTs make it possible to form PTCR (positive temperature coefficient of resistance) in elastomers at lower concentrations, which makes it possible to preserve mechanical strength and use more efficient modes of heat generation. For strain gauges, CNTs improve sensitivity to mechanical effects and extend the measurement range. The use of thermoplastic elastomers provides the temperature of PTCR operation for electric heating at the level of 200 °C (voltage 240 V), which allows such heaters to operate at a power supply from a household electrical network. CNTs-based strain gauges can provide structural condition monitoring of composite materials.