To distinguish between real and fake silicone oil, we must first recognize silicone oil and understand the characteristics of silicone oil.

Silicone oil is a kind of polyorganosiloxane with different polymerization degree chain structure, it is made by dimethyldichlorosilane with water hydrolysis to make the primary condensation ring body, ring body by cracking, distillation to make low ring body, then the ring body, capping agent, catalyst put together to adjust the polymerization can get a variety of different degrees of mixture, by reducing the pressure of distillation to remove the low boiling material can be made of silicone oil.

Silicone oil features: excellent heat resistance, electrical insulation, weather resistance, hydrophobicity, physiological inertia and small surface tension, in addition to low viscosity temperature coefficient, high compression resistance, some varieties also have radiation resistance, non-corrosive to metals, non-toxic, etc.

The role of silicone oil: commonly used as senior lubricant, anti-vibration oil, insulating oil, defoamer, demoulding agent, polishing agent and vacuum diffusion pump oil, etc. Among all kinds of silicone oil, methyl silicone oil is the most widely used and is the most important variety of silicone oil, followed by methyl phenyl silicone oil. In addition, there are also ethyl silicone oil, methyl phenyl silicone oil, silicone oil containing nitrile, etc. Various functional silicone oils and modified silicone oils are mainly used for special purposes.

Identification of genuine and fake silicone oil.

1. observation with the eyes: fake silicone oil will be more turbid, with a stronger odor and foul smell.

2. Test by fire: use a glass rod or iron rod with a small amount of silicone oil ignition, can ignite and black smoke is white mineral oil, pure silicone oil ignited by fire is not burning, and no smell, clear and transparent, non-toxic. The ignition point of silicone oil is 320 degrees.

3. Freezing point test method: silicone oil will not freeze at -50 degrees, while fake silicone oil will appear cloudy or frozen.

Advantages of silicone oil: 

1. Excellent shear stability, has the function of absorbing vibration and preventing vibration transmission, and can be used as vibration damping fluid.

2. Excellent thermal oxidation stability, such as thermal decomposition temperature >300℃, small evaporation loss (150℃, 30 days, evaporation loss is only 2%), oxidation test (200℃, 72h), small change in viscosity and acid value.

3. Excellent electrical insulation, volume resistance, etc. does not change in the range of room temperature ~ 130 ℃ (but the oil can not contain water).

4. It is a non-toxic and low foaming, anti-foaming oil, can be used as antifoaming agent, etc.

5. The viscosity and temperature performance is the best among liquid lubricants, and the viscosity changes little in a wide temperature range. Its freezing point is generally less than -50℃, some of them are as high as -70℃, and its appearance and viscosity do not change when stored for a long time at low temperature, so it is a base oil with high temperature, low temperature and wide temperature range.

Disadvantages of silicone oil:

1. Small surface tension (easy to leak from the machine).

2. Large gas solubility (difficult to design gas seal device).

3. Large coefficient of thermal expansion of silicone oil (may produce overpressure problem).

4. The lubricity of silicone oil is poor, especially for steel-steel friction vice.

5. Certain hygroscopicity (after the water content is higher than 100×10-6, the electrical performance decreases sharply)