Silicone oil

Silicone oil, with English name of silicone oil, CAS No. 63148-62-9 and molecular formula of c6h18osi З, is a kind of polyorganosiloxane with chain structure with different degree of polymerization. It is prepared by hydrolysis of dimethyldichlorosilane with water to obtain the initial polycondensation ring body. The ring body is cracked and rectified to obtain the low ring body. Then the ring body, capping agent and catalyst are put together to adjust and polymerize to obtain various mixtures with different degrees of polymerization. The silicon oil can be prepared by removing the low boiling matter by vacuum distillation.

This information
Silicone oil Chinese Name: silicone oil
English Name: silicone oil
Chinese alias: organic silicone oil; Hard silicone oil; Defoamer; Polysiloxane; Methyl silicone oil; Dimethyl silicone oil; Dimethylpolysiloxane; Dimethylsilicone oil
English alias: hard foam silicon (an even vessel); Hard foam silicon;  Methyl silicone oil ,Polydimethylsiloxane
CAS No.: 63148-62-9
Molecular formula: C6H ₁ OSI ₈
Molecular weight: 162.37932

Physical property data
Density 0.963
Melting point - 50 ° C
Refractive index 1.403-1.406
Flash point 300 ° C
Water soluble practically soluble

Main characteristics
Silicone oil has excellent heat resistance, electrical insulation, weather resistance, hydrophobicity, physiological inertia and small surface tension. In addition, it also has low viscosity temperature coefficient and high compression resistance). Some varieties also have radiation resistance.
Silicone oil has many special properties, such as oxidation resistance, high flash point, low volatility, no corrosion to metals, non-toxic and so on.
Basic classification
According to the chemical structure, it can be divided into methyl silicone oil, ethyl silicone oil, phenyl silicone oil, methyl hydrogen containing silicone oil, methyl phenyl silicone oil, methyl chlorophenyl silicone oil, methyl ethoxy silicone oil, methyl trifluoropyl silicone oil, methyl vinyl silicone oil, methyl hydroxy silicone oil, ethyl hydrogen containing silicone oil, hydroxy hydrogen containing silicone oil, cyanogen containing silicone oil, etc;
According to the purpose, there are damping silicone oil, diffusion pump silicone oil, hydraulic oil, insulating oil, heat transfer oil, brake oil, etc.
Main purpose
It is commonly used as high-grade lubricating oil, shockproof oil, insulating oil, defoaming agent, release agent, polishing agent and vacuum diffusion pump oil. Among all kinds of silicone oil, methyl silicone oil is the most widely used and the most important variety in silicone oil, followed by methyl phenyl silicone oil. In addition, there are ethyl silicone oil, methyl phenyl silicone oil, nitrile containing silicone oil, etc. Various functional silicone oils and modified silicone oils are mainly used for special purposes.
Advantages and disadvantages
advantage
(1) Excellent shear stability, has the function of absorbing vibration and preventing vibration propagation, and can be used as damping fluid.
(2) The temperature change of evaporation and heat loss of oxidation (such as 722 ℃) are small, and the heat loss of evaporation is more than 300 ℃. In the test, the heat loss of oxidation is only good (for example, the temperature change of evaporation is more than 200 ℃).
(3) Excellent electrical insulation, volume resistance, etc. do not change in the range of normal temperature ~ 130 ℃ (but there is no water in the oil).
(4) It is a non-toxic, low foaming and strong anti foaming oil, which can be used as defoamer.
(5) The viscosity temperature performance is the best among liquid lubricants, and the viscosity change is small in a wide temperature range. Its freezing point is generally less than - 50 ℃, and some are as high as - 70 ℃. It is stored for a long time at low temperature. The appearance and viscosity of its oil have no change. It is a base oil with high temperature, low temperature and wide temperature range.
shortcoming
(1) Low surface tension (easy to leak from the machine).
(2) Gas solubility is large (it is difficult to design gas sealing device).
(3) The thermal expansion coefficient of silicone oil is large (overpressure may occur).
(4) The lubricity of silicone oil is poor, especially for steel friction pairs.
(5) Certain hygroscopicity (water content higher than 100%) × After 10-6, the electrical performance drops sharply)
System number
CAS No.: 63148-62-9
application area 
Silicone oil has a wide range of applications. It is not only used as special materials in aviation, cutting-edge technology and military technology departments, but also used in various departments of the national economy. Its application scope has been expanded to: construction, electronic and electrical, textile, automobile, machinery, leather and papermaking, chemical light industry, metal and paint, medicine and medical treatment, etc.
The main applications of silicone oil and its derivatives are: film remover, damping oil, dielectric oil, hydraulic oil, heat transfer oil, diffusion pump oil, defoamer, lubricant, hydrophobic agent, paint additive, polishing agent, additive for cosmetics and daily necessities, surfactant, particle and fiber treatment agent, silicone grease and flocculant.
Future development
Silicone oil as a new industry, antirust oil, steel grating belt conveyor, ultrasonic level gauge, art coating, oil and gas boiler has a great development prospect. Silicone oil has many uses and can be used as defoamer, lubricant, release agent, etc. Now the silicone oil market is gradually developing towards the trend of stabilization and expansion.
Harm to human body
Silicone oil was used as a prosthetic product for female breast enhancement. After being used for more than 40 years, silicone oil was found to cause decline in human immune function or cancer in the early 1990s, and was banned in Europe and the United States. At that time, the company that produced silicone gel prosthesis in the United States was prosecuted and lost a lot of money. In the past two years, it has been found that the causes of cancer in women undergoing breast augmentation are more complex. Silicone oil is open to use in Europe, but it is still banned in the United States.
Some products based on silicone oil will be slightly corrosive, so more attention should be paid in the process of transportation and production.
security information
Dangerous goods transportation Code: un1993
Hazard category code: 36 / 37 / 38
Safety instructions: 24 / 25