Hexaphenylcyclotrisilazane is one of the most important cyclosiloxanes. It has good hydrolysis stability because its phenyl groups have high steric hindrance. It can effectively improve the heat resistance of silicone rubber if it is applied to heat resistance agents to prevent oxidative crosslinking and main chain degradation of silicone rubber side chains. And when it is heated at a temperature of 400℃ for a long time, it can be formed into a polymer for a good heat resistant coating. less