Compared with general general rubber, the coordination components of all three categories of silicone rubber are relatively simple, and the hot vulcanization type is the same. In addition to raw rubber, coordination agent mainly includes reinforcing agent, vulcanizing agent and some special additives, generally only need 5~6 components can be composed of practical formula. The formulation design of silicone rubber should take into account the following points.

(1) Silicone rubber is a raw rubber with high saturation. It can not be vulcanized with sulfur, but by hot vulcanization. Hot vulcanization is organic peroxide as vulcanizing agent, so the rubber shall not contain active substances that can react with peroxide decomposition products, otherwise it will affect vulcanization.

(2) Silicone rubber products are generally used at high temperature, and their coordination agent should be stable at high temperature. Therefore, inorganic oxide is usually selected as reinforcement agent.

(3) Silicone rubber is easy to cause the cracking and rearrangement of siloxane bonds under the action of trace acid or alkali and other polar chemical reagents, resulting in the reduction of the heat resistance of silicone rubber. So in the selection of coordination agent must take into account their acid alkaline, but also should take into account the acid of peroxide decomposition products, so as not to affect the performance of vulcanizate.

(4) Selection of raw rubber When designing the formula, raw rubber with different characteristics should be selected according to the performance and use conditions of the product. For general silicone rubber products, the temperature is required to be in the range of -70℃~250℃, and vinyl silicone rubber can be used; When the temperature of the product is higher (-90~300℃), low phenyl silicone rubber can be used; When products require high and low temperature resistance and resistance to fuel or solvent, fluorosilicone rubber should be used.