The linear phenylmethylsilicone fluid can be regarded as a product of a partial methyl group in dimethyl silicone oil substituted by a phenyl group.
Methyl phenyl silicone oil has a higher viscosity temperature coefficient, lower freezing point and flash point than the same viscosity dimethyl silicone oil, and the compression resistance changes faster under pressure. Low phenyl silicone oil has remarkable low temperature resistance and fluidity at -70 °C. As the phenyl mole fraction increases, the silicone oil has improved high temperature resistance, radiation resistance, lubricity, and solubility in an organic solvent, but the low temperature resistance is lowered.


Silicone oil with a high phenyl mole fraction is oxidized when heated above 250 °C, and the viscosity is increased; especially for silicone oil with a phenyl mole fraction of 50%, the stabilizer may be used at 300-350 ° C for several hundred hours.