The raw rubbers of one-component and two-component condensation RTV silicone rubbers are all α,ω-dihydroxy polysiloxanes; addition-type RTV silicone rubbers contain alkenyl groups and hydrogen side groups (or end groups) Polysiloxane, because it can get a good curing effect at a temperature slightly higher than room temperature (50～150℃) when it is cured, it is also called low temperature vulcanized silicone rubber (LTV).