Platinum-cured silicone rubber, also known as addition cure silicone rubber, is a liquid silicone rubber compound vulcanized at room temperature using platinum catalysts. This ultra-clean, high-purity, translucent silicone elastomer requires the mixing of silicone polymer and catalyst to initiate the curing process. With a simple 1A:1B weight or volume mixing ratio, this low-viscosity liquid silicone is easily mixed and poured. The curing process can be greatly accelerated through heat curing.
Platinum-cured liquid silicone offers fast cure, a range of hardness options (0-50 Shore A), and can achieve an infinite number of color effects by adding silicone pigments. These products exhibit extremely low shrinkage and high physical properties. They have been tested to meet the requirements of federal regulations FDA extraction test CFR 177.2600 and can be safely used in contact with food.
Curing Principle: Platinum-catalyzed addition curing, also known as hydrosilylation, is a reaction between cross-linkers rich in Si-H and vinyl-functionalized polysiloxanes. Unlike tin-cured silicone, the cure is initiated by the platinum catalyst and not moisture, so there are no issues with section thickness. Two-part systems do not release reaction by-products, allowing them to cure in closed environments.
Composition: The primary constituents of addition-cure silicone include 107# base rubber (room temperature vulcanized methyl silicone rubber), hydrogen silicone fluid (Polymethylhydrosiloxane), vinyl silicone fluid, platinum catalyst, inhibitor, and cross-linking agent. Part A contains the catalyst in the form of a platinum complex, while part B contains the cross-linker (H-siloxane).