Silicone foam is a synthetic rubber product used in gasketing, sheets and firestops. It is available in solid, cured form as well as in individual liquid components for field installations.[1]
When the constituent components of silicone foam are mixed together, they evolve hydrogen gas, which causes bubbles to form within the rubber, as it changes from liquid to solid. This results in an outward pressure. Temperature and humidity can influence the rate of expansion.