Brief description of dimethicone oil
Silicone oils, usually referred to as linear polysiloxane products that remain liquid at room temperature, have the structural formulas shown in Figure 1 and simulated in Figure 2.
Structural formula of linear polysiloxane
Analog formula of silicone oil
It is particularly widely used in our life and production, and is most commonly used in medical treatment, cosmetics, lubricants, work oils, anti-vibration oils, heat carriers and so on.
Some applications of silicone oil
Commercially available silicone oils can be divided into 4 categories according to their structure: hydrocarbon-based silicone oils, silicone-functional silicone oils, carbon-functional silicone oils and inactive modified silicone oils. Here we only talk about hydrocarbon-based silicone oil, dimethyl silicone oil is one of the main representatives of hydrocarbon-based silicone oil, so to dimethyl silicone oil as an example, and listen to the editor slowly.
Dimethicone oil (that is, R, R ‘and X are methyl) is the largest production of silicone oil and the most widely used a variety of its typical polysiloxane characteristics, such as resistance to high and low temperatures, oxidation, low viscosity-temperature coefficient, shear, low vapor pressure, low surface tension, hydrophobic, anti-foam, demolding, electrical insulation and physiological inertia, and so on.
Linear and branched silicone oil main chain and branched chain are composed of Si-O-Si, its end group and side groups are all hydrocarbon (such as methyl, ethyl, etc.), so it can be produced by the corresponding monomer or intermediates.
Molecular formula of dimethicone oil
Industrially, dimethyl silicone oil is mainly produced by four methods:
(1) MeSiCl2 and Me3SiCl hydrolysis condensation method;
Hydrolysis condensation method
The method (1) uses the cheapest raw materials, however, the process is cumbersome, corrosion is serious, coupled with the high purity requirements of the monomer, even if it contains very few impurities, can also seriously affect the product properties. Therefore not practical.
(2) MeSiCl2 hydrolysate (i.e., a mixture of (Me2SiO)n and HO(Me2SiO)nH) with MM or Me3SiO(Me2SiO)2-5SiMe3 catalytic equilibrium method;
Reaction (2) Equation
(3) (Me2SiO)n with MM or Me3SiO(Me2SiO)2-5SiMe3 catalytic equilibrium method;
(4) HO(Me2SiO)nH with MM or Me3SiO(Me2SiO)1-5SiMe3 catalyzed condensation method.
2. Application of silicone oil in textile industry
Methyl silicone oil is used in a large number of fibers, raw silk and cotton with oil agent, spinning with oil agent, sewing thread with smoothing agent. Raw silk and cotton with oil agent for low viscosity methyl silicone oil, generally 10 viscosity. The smoothing agent for sewing thread is medium-high viscosity methyl silicone oil, and generally 500 viscosity silicone oil is used. The use of methyl silicone oil thermal stability and low viscosity and temperature coefficient, with anti-static agents, emulsifiers and other oils made of spinning oils, used in nylon, polycool spinning process, to prevent the process of spraying very fine monofilament beams from the nozzle spraying time and rapid winding occurred at the time of the electric charge caused by the breakage of the silk and loosening. For melt-proofing, the nozzle is also de-molded with methyl silicone oil to prevent the attachment of carbides or melts from causing breakage. In addition to the textile as an additive to achieve textile functionality, silicone products will also be used in other areas of textiles, such as silicone and polyurethane combination to form the coating of fabrics; silicone and acrylic polymerization to form the printing of fabrics; silicone and fluorine combination to form the surface of the textile waterproof coating and so on.
