The preparation of methyl vinyl rubber is mainly achieved through ring opening polymerization reaction. Using octamethylcyclotetrasiloxane as the main monomer, anionic or cationic ring opening polymerization is carried out under the action of a catalyst, and ethylene containing ring monomers are added as comonomers to evenly distribute ethylene groups in the polymer chain. During the reaction process, it is necessary to strictly control the temperature, pressure, and catalyst concentration to ensure a narrow molecular weight distribution and a regular structure. After polymerization is completed, the catalyst is deactivated through high-temperature treatment, and pure raw rubber products are obtained through processes such as removing low molecular weight volatiles.

During the processing, methyl vinyl rubber exhibits excellent mixing performance. Due to the flexible molecular chain, raw rubber is easy to plasticize in open or internal mixers, and can evenly disperse various fillers and additives. The commonly used reinforcing filler is gas-phase white carbon black, which can significantly improve the tensile strength and tear resistance of vulcanized rubber. The vulcanization system often uses peroxide initiators, which generate free radicals under heating conditions, triggering cross-linking reactions between vinyl groups and forming a three-dimensional network structure. The vulcanization temperature is usually controlled between 160 and 180 degrees Celsius, and the time is adjusted according to the thickness of the product.

This material exhibits good adaptability in processes such as extrusion, compression molding, and injection molding. Smooth surface and good dimensional stability during extrusion; The compression molding has a low shrinkage rate and high product accuracy. Due to the moderate viscosity of the raw rubber itself, it is not easy to stick to the rollers or molds during the processing, which is conducive to continuous production. In addition, it has fewer by-products from the vulcanization reaction, fewer internal defects in the product, and high density. By adjusting the vinyl content and molecular weight, the matching between processing flowability and vulcanization speed can be further optimized to meet the forming requirements of complex shaped products.

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