Generally speaking, with the increase of phenyl content, the rigidity of silicone rubber molecular chain gradually increases, and the low temperature resistance of silicone rubber gradually decreases, but with the increase of phenyl content, the fire resistance and radiation resistance of vulcanized rubber are improved.
The properties of phenyl silicone rubber vary with the content of phenyl in the molecular chain, and are divided into three categories: low phenyl silicone rubber, medium phenyl silicone rubber and high phenyl silicone rubber.
① Low phenyl silicone rubber
The content of phenyl is 5-10%, and the hardening temperature of rubber is reduced to -115 ° C, which makes it have unique cold resistance, and can still maintain the elasticity of rubber at -70~-100 ° C, which is one of the best low temperature properties of all rubber.
② Medium phenyl silicone rubber
Phenyl content 15-25%, with ablative resistance and fire resistance characteristics, once on fire can self-extinguish.
③ High phenyl silicone rubber
When the content of phenyl is above 30%, it has excellent radiation resistance, γ-ray resistance 2.58×10⁴c/kg, used under radiation conditions, and still maintains good mechanical properties. ‍

Potting Silicone Rubber, plz check MY 1500