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Silicone rubber is hot vulcanized and room temperature vulcanized. Hot vulcanization type is divided into methyl silicone rubber (MQ), methyl vinyl silicone rubber (VMQ, the amount and product brand more), methyl vinyl phenyl silicone rubber PVMQ (low temperature resistance, radiation resistance), other eyes silicone rubber, fluorine silicone rubber, etc. MQ is a colorless transparent high viscosity plastic straight chain polymer compound. The main chain is composed of silicon and oxygen atoms. The side group connected with silicon is methyl, and the molecular weight is between 500,000 and 800,000. VMQ is a colorless transparent high viscosity plastic straight chain polymer compound. The main chain is composed of silicon and oxygen atoms. The side groups connected to silicon are methyl and vinyl, and the molecular weight is between 500,000 and 800,000. PVMQ is obtained by introducing diphenyl siloxy chain or methyl phenyl siloxy chain into the molecular chain of vinyl silicone rubber.
Temperature range: -60℃ (special to -115℃) ~ 204℃ (special to 260℃)

Advantages:
· Excellent heat and cold resistance
· Good electrical insulation
· Excellent ozone resistance
· Excellent weather resistance
Disadvantages:
· Low tensile strength
· Poor tear resistance and wear resistance
· Poor oil and solvent resistance

Applicable media:
· Animal and vegetable oils and fats
· High molecular weight chlorinated aromatic hydrocarbons
· Medium water resistance
· Low concentration salt solution
· Ozone resistance, aging resistance and weather resistance
Not suitable for media:
· Superheated water vapor above 121℃
· Acid and base
· Small molecular weight chlorinated hydrocarbons (trichloroethane)
· Hydrocarbon based fuel oil