Thermal degradation in silicone liquid/aramid paper insulation system

Abstract

We have studied the thermal degradation of silicone liquid and aramid paper insulation system. The flash point of degraded silicone liquid was lower than initial one. Thermal degradation products of silicone liquid were cyclic siloxane compounds and gases. The decrease in the flash point is due to generation of cyclic siloxane compounds. The major components of cyclic siloxane compounds are D3, D4, D5 and D5. By measuring the total amount of cyclic siloxane compounds by gas chromatography, the degree of the degradation of silicone liquid can be estimated. The main gaseous products are CH4 and H2, and those of aramid paper are CO2 and CO. When silicone liquid is heated together with aramid paper, major part of the produced gases are also these gases.