A brief introduction to phenyl silicone oil, a colorless or yellowish transparent oily substance. The flash point is less than 300 ° C. The freezing point of the silicone oil containing 5mo1% phenyl is as low as -70 ° C, the surface tension is about 2.1.10-4-2.85 × 10-4N/cm, the relative density is 1.00-1.11, and the refractive index is 1.425-1.533. It has good thermal stability, the gelation time in 250 ° C hot air is 1750 h, and it also has good irradiation resistance, high oxidation stability, heat resistance, fire resistance, UV resistance and chemical resistance. The hydrolysates of octadecylcyclotetrasiloxane, dimethyltetraphenyldisiloxane and methylphenyldiethoxysilane can be prepared by adjusting polymerization in the presence of catalyst. Used as the carrier of lubricating oil, heat exchange fluid, insulating oil, gas-liquid chromatography, etc. . Used for insulation, lubrication, damping, shock, dust and high temperature heat carrier, is the ideal liquid damping dielectric liquid for electronic instruments.