Methyl phenyl vinyl silicone rubber is referred to as p […]
Methyl phenyl vinyl silicone rubber is referred to as phenyl silicone rubber. This kind of rubber is obtained by introducing diphenyl silicone chain links or methyl phenyl silicone chain links into the molecular chain of vinyl silicone rubber.
According to the phenyl content (phenyl: silicon atom) in silicone rubber, it can be divided into low phenyl, medium phenyl and high phenyl silicone rubber. When the rubber crystallizes or is close to the glass transition point, or the two conditions overlap, the rubber will appear rigid. The introduction of an appropriate amount of bulky groups can destroy the regularity of the polymer chain, which can reduce the crystallization temperature of the polymer. At the same time, because the introduction of bulky groups changes the force between polymer molecules, the glass can also be changed. temperature. Low phenyl silicone rubber (C6H5/Si=6~11%) has excellent low temperature resistance due to the above reasons, and has nothing to do with the type of phenyl monomer used. The brittle temperature of vulcanized rubber is -120℃, which is the best rubber with low temperature performance today. Low phenyl silicone rubber has the advantages of vinyl silicone rubber, and the cost is not very high, so it has a tendency to replace vinyl silicone rubber. When the phenyl content is greatly increased, the rigidity of the molecular chain will increase, resulting in a decrease in cold resistance and elasticity, but the ablation resistance and radiation resistance will be improved, and the phenyl content will reach C6H5/Si=20~34 % Is middle phenyl silicone rubber with ablation resistance, high phenyl silicone rubber (C6H5/Si=35~50%) has excellent radiation resistance.