Methyl phenyl vinyl silicone rubber
Methyl phenyl vinyl silicone rubber (MPVSIR) is a product of introducing methyl phenyl silica or diphenyl silica into the molecular chain of MPVSIR. The introduction of phenyl into the side group of polysiloxane greatly reduces the crystallization temperature of the polymer and enlarges the application range of the polymer at low temperature due to the destruction of the regularity of the structure of dimethylsiloxane. Therefore, besides all the compression permanent deformation, wide temperature range, oxidation resistance, weather resistance, shock resistance, moisture proof and good electrical insulation properties of methyl vinyl silicone rubber, methyl phenyl vinyl silicone rubber also has excellent low temperature resistance, ablation resistance and radiation resistance. These properties depend on phenyl in molecular chain. Generally speaking, phenyl content (the ratio of phenyl to silicon atom) is called low-phenyl silicone rubber when it is 5-10%. It has unique cold resistance. It can still keep elasticity of rubber at - 70-100 C. It is one of the best low-temperature properties of all rubber, and it also has methyl vinyl silicone rubber. Because of its advantages and low cost, there is a tendency to replace methyl vinyl silicone rubber. Medium phenyl silicone rubber is called medium phenyl silicone rubber when its phenyl content is 20-40%. It has excellent flame resistance and can extinguish itself once ignited. High phenyl silicone rubber is called high phenyl silicone rubber when the phenyl content is 40-50%. It has excellent radiation resistance and gamma-ray resistance is 1xI08 roentgen. Generally speaking, with the increase of phenyl content, the rigidity of silicone rubber molecular chain increases gradually, and the low temperature resistance of silicone rubber decreases gradually, but with the increase of phenyl content, the flame resistance and irradiation resistance of vulcanizates are improved. Methyl phenyl vinyl silicone rubber is one of the most important materials in aerospace industry, advanced technology and other sectors of national economy. It can be used to make various moulding and extrusion products for cold-resistant rubber in aerospace industry and sealing rings, gaskets, pipes and bars for ablation, heat aging or radiation resistant parts.