Phenyl silicone oil and methyl silicone oil: chemical game of temperature resistance performance Phenyl silicone oil significantly improves its high temperature resistance by introducing phenyl groups into the polysiloxane chain. Low phenyl silicone oil (with a phenyl content of 5% -10%) remains stable within the range of -50 ℃ to 200 ℃ and is suitable for low-temperature lubrication of electronic components. The temperature resistance of medium phenyl silicone oil (with a phenyl content of 25%) is further enhanced, and it is commonly used in aviation hydraulic oil and high-temperature sealants. High phenyl silicone oil (phenyl content>45%) has significantly increased viscosity and decreased flowability due to its high phenyl content. However, it can be used for a long time above 300 ℃ and is an ideal choice for extreme high temperature environments. In contrast, although methyl silicone oil has a lower cost, its temperature resistance limit usually does not exceed 200 ℃, and it is prone to oxidative crosslinking at high temperatures. The disadvantage of phenyl silicone oil is its high cost, and excessive phenyl content may lead to decreased lubricity. When making a choice, it is necessary to weigh the temperature resistance requirements and cost-effectiveness.