Colorless or yellowish transparent oil. Flash point >300 ℃. The freezing point of 5mo1% phenyl silicone oil is as low as -70 ℃, and the surface tension is about 2.1 × 10-4～2.85 × 10-4n/cm, relative density 1.00-1.11, refractive index 1.425 ~ 1.533. Good thermal stability. The gel time in 250 ℃ hot air is 1750h. It also has good radiation resistance, high oxidation stability, heat resistance, flame resistance, UV resistance and chemical resistance. It can be prepared by telomerization reaction of hydrolysates of octamethylcyclotetrasiloxane, dimethyltetraphenyldisiloxane and methylphenyl diethyloxysilane in the presence of catalyst. It is used as a carrier for lubricating oil, heat exchange fluid, insulating oil, gas-liquid chromatography, etc. Used for insulation, lubrication, damping, shockproof, dustproof and high temperature heat carrier, it is an ideal liquid damping dielectric fluid for electronic instruments.