Carbon black/octadecane composites for room temperature electrical and thermal regulation

Electrical and thermal switchable materials are of interest in temperature regulation, circuit protection, sensors and other field. In this paper, functionalized carbon black (CB)/octadecane composites were synthesized for room temperature electrical and thermal switch. With these composites, large contrast ratios of electrical conductivity (EC) and thermal conductivity (TC) are achieved around the phase transition temperature (28-29 °C). The corresponding contrast ratios of EC and TC reach 4.3 × 105 and 3.3 times, respectively. The composites show remarkable stability and durability during the cycling experiments. The mechanisms of good stability and high EC contrast ratio are discussed as well.