High Phenyl Silicone Rubber

High phenyl silicone rubber
High molecular weight linear polysiloxanes containing phenyl siloxane or methyl phenyl siloxane links in the backbone
Introduction: When the content of phenyl is above 30%, it is commonly known as high phenyl silicone rubber, which has excellent radiation resistance. High molecular weight linear polysiloxanes containing phenyl siloxane or methyl phenyl siloxane links in the backbone. After mixing with fillers, organic peroxide vulcanizing agents and processing AIDS, the elastomer can be vulcanized by heating
Classification: According to the content of phenyl, it can be divided into low phenyl, medium phenyl and high phenyl
Characteristics: Phenyl silicone rubber in addition to methyl vinyl silicone rubber compressed water deformation, wide temperature range, aging resistance, shock resistance, moisture resistance and excellent electrical insulation properties, but also has excellent low temperature resistance, ablative resistance and radiation resistance. Due to the introduction of phenyl in the molecular structure, the regularity of the molecular structure of siloxane is destroyed, the crystallinity of the polymer is reduced, and the cold resistance is improved.
For example: medium phenyl silicone rubber has excellent cold resistance, once it catches fire, it can self-extinguish, and high phenyl silicone rubber has excellent radiation resistance. With the increase of phenyl content, the molecular rigidity increases, the radiation resistance and the fire resistance improve, but the cold resistance decreases. The methyl phenyl mixed tetracyclic body and tetramethylvinylcyclotetrasiloxane are copolymerized under the catalysis of alkali catalyst, and the raw rubber is prepared after destroying the catalyst and removing the low boiling matter by vacuum. The rubber is mixed with the white carbon black and the organic peroxide structure control agent on the rubber mixer.
Uses: It is molded and extruded into all kinds of products. It is used as sealing ring, pad, pipe and bar for low temperature resistance, radiation resistance and ablative resistance in aviation and aerospace departments.
Features: Phenyl silicone rubber is used in occasions requiring low temperature resistance and heat insulation. Medium and high phenyl silicone rubber are difficult to process. The physical and mechanical properties are poor, and the production and application are limited to some extent. It is made by introducing diphenyl siloxane link (or methyl phenyl siloxane link) into the molecular chain of vinyl silicone rubber. This is done by introducing a large volume of phenyl group to destroy the regularity of the dimethylsiloxane structure and reduce the crystallization temperature and glass transition temperature of the polymer. At this time, the rubber hardening temperature is reduced to the lowest value (-115 ° C), so that it has the best low temperature resistance, and still has flexible elasticity at -100 ° C.