Silicone is so widely used! Let's learn silicone oil production technology
Silicone oil is a kind of linear small molecule silicone polymer with Si-O-Si as the main chain and organic groups in the side chain. It is widely used in textile, daily chemical, mechanical processing, chemical, electrical and electronic, medical and health, etc. industry. Silicon oil is usually kept in a liquid state at room temperature. As the molecular weight increases, the viscosity also increases, so viscosity is an important physical property index of silicone oil.
2017 China's silicone oil consumption situation
Classification of silicone oil
Silicone oil is generally divided into two categories: general silicone oil and modified silicone oil.
There is also a class of co-modified silicone oils and derivatives - ternary modified silicone oil
Silicone oil properties
Silicone oil is generally a colorless, odorless, non-toxic, non-volatile liquid with the following characteristics.Good heat resistance
The Si-O-Si-bond energy is 108 kcal/mol, which can be used for a long time at -60 to 220 °C; the introduction of a phenyl group is resistant to low and high temperatures.Good oxidation resistance and weather resistance
It is only oxidized at 200 ° C. The addition of antioxidants can significantly prolong the high temperature gelation time of silicone oil.Good electrical insulation
It has good dielectric properties and its electrical properties change little with changes in temperature and cycle number. For example, the dielectric constant is 2.76; the volume resistivity decreases with increasing temperature.Good hydrophobicity
The main chain is composed of a polar silicon-oxygen chain, and the side chain is a non-polar alkyl group oriented outward, which effectively blocks the entry of water molecules. The interfacial tension of silicone oil to water is about 42 dynes/cm.Small viscosity coefficient
It is the material with the best viscosity-temperature characteristics among various liquid lubricants.High resistance to compression
Viscosity can vary greatly with increasing pressure, but lower than typical mineral oil. For example, at 2000 atmospheres, the viscosity of petroleum rises.50~5000 times, while the viscosity of silicone oil is increased by 10 timesLow surface tension
The surface tension is generally between 20.8 and 21.1 dynes/cm; the water is 72 dynes/cm, the ethanol is 22.3 dynes/cm, and the mineral oil is 30 to 35 dynes/cm. Good defoaming properties, barrier properties and lubricity with other materialsNon-toxic, tasteless and physiologically inert
It is one of the most inactive compounds known and has no rejection reaction with animal organisms.Good lubricity
No adverse reactions to rubber, plastics, coatings, etc.; Newtonian fluid, less change in viscosity under high shear; introduction of chlorophenyl or methyl group with trifluoropropyl to improve lubrication performanceChemical properties
Silicon-oxygen bonds are not resistant to strong acids and bases; insoluble in water or aqueous solvents; aromatic, aliphatic and chlorinated hydrocarbons are the best solvents; they are also soluble in ethers, esters, higher alcohols and ketones.Silicone secondary processing products
Definition: Silicone oil as raw material or main agent, adding thickener, surfactant, solvent, filler and various performance improvers, etc., compound, emulsion, solution and other products prepared by a specific process, called silicone oil Secondary processed products.
Silicone oil production technology
Methyl silicone oil
- Production methods commonly used in industry
- Other commonly used methods:
（2）Equilibrium reaction of hydrolyzate of dimethyldichlorosilane with hexamethyldisiloxane
- Production route
- Main equipment
- Process conditions
2. Hydroxy silicone oil
The dimethylcyclosiloxane is used as a raw material, and ring-opening polymerization is carried out in the presence of a base catalyst. After polymerization to a certain extent, an appropriate amount of water is added to telomerize, and the terminal chain is terminated with a hydroxyl group.
3. Polyether modified silicone oil
Two methods for hydrolyzed polyether modified silicone oil.1.One is the reaction of an alkoxy oil and a monoalkyl polyether
1.Hydrogen-containing silicone oil and unsaturated polyether hydrosilylation;
2. Esterification of carboxylic acid-containing silicone oil with monoalkyl polyether
4. Amino modified polyether silicone oil
Two methods for synthesizing amino-modified polyether polysiloxanes:1. The amine hydrolysis reaction is carried out with an epoxy group-containing polyether silicone oil.
2. Adding an amino group between the polysiloxane segment and the polyether segment or at the end of the polyether segment by a ring opening reaction of the aminopolysiloxane with the epoxy polyether
5. Silicone grease
Preparation processDesign formula according to the variety of products and grade.
l. Add the material to the planetary agitation or evaporative mixer and mix evenly under heating and reduced pressure.
2. Grinding with a three-roller or colloid mill
3 Defoaming, filtration, packaging
6 Defoamer
Preparation process1. Oily type defoamer is directly used for silicone oil. Ointment type is a defoamer in the form of ointment formulated with silica added to silicone oil.
2. Solution-type defoamer - dissolves silicone oil or silicone paste in various mailing solvents
3. Emulsion type defoamer - an oil-in-water (O/W) emulsion prepared by emulsification of silica gel in the presence of an emulsifier and water by mechanical stirring.
4. Self-emulsifying defoamer - general polyether modified silicone oil
5. Powder solid type defoamer - The emulsion type silicone oil defoamer is adsorbed on the upper limit of porous silica gel, cellulose, salt, calcium carbonate and the like with large oil absorption
https://www.ywlchemical.com/category/defoamer/
https://www.linkedin.com/company/china-defoamer
https://invelydefoamer.blogspot.com/
Edited by Invelychem
评论
发表评论