Silicone rubber polymer is a chain structure linked by Si-O bond, and its main component is linear polysiloxane. Silicon-O-Si bond is the main chain of silicon-oxygen bond, which is helical to offset the polarity of silicon-oxygen bond, and the side chains are generally low polar or non-polar groups, so the polarity of the whole macromolecule is very low, which makes silicone rubber show hydrophobicity, oxidation resistance and aging resistance. In addition, the polarity of the Si-O bond in the main chain and the Si-C bond in the side chain are similar to that of the ion bond, and there are no cracking and oxidation reactions at normal operating temperature (below 250 C). Therefore, they have excellent heat resistance and can be used as medical devices, artificial organs and drug delivery systems with good biocompatibility to human body. Because of the small intermolecular force of silicone rubber, its film has better air permeability than ordinary rubber and plastic wax film, and has strong selectivity for different air permeability, such as gas exchange membrane medical products, artificial organs in vivo and so on.
The design, production and sales of medical silicone rubber products are basically the same as those of ordinary silicone rubber products, but the requirements for materials, manufacturing process, processing equipment, production environment and product packaging are much higher than those of ordinary products. Because silicone rubber products in vivo are used in vivo, the formulation should be simple, and auxiliary materials should not be added as far as possible. All kinds of matching materials should be pure, and toxic substances should not be added. The main reinforcing agent commonly used is white carbon black. The vulcanizing agent generally uses peroxide, such as 2,4-dichlorobenzoyl peroxide (DCBP) and 2,5-dimethyl-2,5-di-tert-butyl peroxide hexane (DBPMH), in order to facilitate operation and prevent structural tendency, a small amount of hydroxyl siloxane and alkoxysilane are often added in the process. Operating aids such as.  For example, the formulation of moulded vulcanized silicone rubber: methyl vinyl silicone rubber 100; silica A-245-50 for silica gel; DBPMH 0.5-1;; hydroxyl silicone oil 2-3. Formula of high tear resistance silicone rubber for hot air vulcanized extruded products: methyl vinyl silicone rubber 100; fumed silica W909 50; paste DCBP (40%) 1.5.