A study on fluoroelastomer/MWCNTs-COOH dielectric composite with high temperature and acid resistance

A novel dielectric material of fluoroelastomer/MWCNTs-COOH (acidified MWCNTs) composite that can be applied in the harsh conditions was prepared by a simple solution blending method. Thermogravimetic analysis was applied to evaluate the thermal stability of the fluoroelastomer/MWCNTs-COOH composite. It shows that the thermal decomposition temperature is greater than 400 °C. Besides, the thermal decomposition mechanism and service life of the composites were determined by various thermal decomposition kinetics methods. The results show that the thermal decomposition mechanism of the composite belongs to the first-order reaction, and the limit temperature of 2 years of use is 227.8 °C. Due to the excellent electrical properties of MWCNTs, the dielectric constant of the composite increases by 28.2% with only 1.5 wt% fillers loading. Most importantly, the composite shows excellent corrosion resistance. There are few changes in dielectric properties of the composite after soaked in acid for 9 days. The dielectric constant does not change more than 1.5, and the dielectric loss is basically unchanged. Therefore, such composite is a good candidate for high performance dielectric material used at elevated temperature or acid environment.