Thermal control coating is an important functional coating material in space shuttle thermal controlling system. In this work, the temperature resistance, decomposition characteristics, electrical properties (dielectric constant, loss tangent) and degradation of electrical properties of the thermal control white paint ACR-1 under strong vacuum electromagnetic field conditions were studied. Results showed that when thermal control coatings entered the stage of thermal decomposition, the apparent color of thermal control coatings became darker, the compact structure of coating turned into porous structure, the loss tangent value increased with the increase of the degradation degree, and the loss of energy in the electromagnetic field in the thermal control coatings increased accordingly, which increased the thermal equilibrium temperature of thermal control coatings. When the coating material was completely decomposed and carbonized, the loss tangent increased rapidly, and the loss of electromagnetic wave increased rapidly, and the electrical performance index of equipment decreased significantly, which caused the coatings to be deviated from the design requirements.
