The silica is roughly classified into a precipitated silica and fumed silica according to a production method.

Fumed silica and precipitated silica are essentially indistinguishable, and the chemical name is silica. However, the fumed silica production is silica obtained by burning silicon tetrachloride and air, and the fineness is more than 1000 mesh. The precipitation method is to precipitate silica by adding sulfuric acid into sodium silicate. The fineness is only 300-400 mesh. The silica produced by fumed silica is expensive and does not readily absorb moisture. Use as a matting agent in paints. Precipitated silica is cheap and easy to absorb moisture.

Precipitated silica features, bonding, anti-aging, anti-caking, cohesion, controlled release, carrier, flow aid, improved printing, mechanical action, special additives, reinforced thermoplastics, rheology control, whitening. Hydrophobic silica is readily soluble in oils and is used as a reinforcing filler in rubber and plastics to improve the mechanical strength and tear resistance of the product. Due to the different manufacturing methods, there are certain differences in physical and chemical properties and microstructures, so their application fields and application effects are also different.

Introduction of precipitated silica
Precipitated silica, also known as hydrated silicic acid, light silica, the chemical expression is usually written as · mSiO2 · nH2O, the appearance of white highly dispersed amorphous powder, also processed into pellets as a commodity. The ratio is 2.319 to 2.653, and the melting point is 1750 degrees. Insoluble in water and most acids, when absorbed in the air, becomes concentrated fine particles.

Soluble in caustic soda and hydrofluoric acid. Other chemicals are stable, resistant to high temperature decomposition, and do not burn. High electrical insulation, large porosity, large internal surface area, good water absorption and non-toxicity.

The hydrophobicity and hydrophobicity of silica are easily soluble in oils and are used as rubber reinforcing agents to improve the mechanical strength and tear resistance index of the products. Due to different preparation methods, the physical and chemical properties and microstructure of silica have certain differences, so their application fields and application effects are also different.

The difference between precipitated silica and fumed silica:
1. the difference in production process.
2. the difference in adaptability.
3. the difference in particle size and use effect.
4. of course, the most important thing is the difference between price and enterprise cost accounting.

Application areas of silica:
Silica is used in adhesives made of natural rubber or synthetic rubber to provide thixotropic and reinforcing properties, and at the same time, it can improve adhesion due to its stretchability, and is inexpensive.

Rubber and synthetic rubber: One of the most important uses is synthetic silicone rubber. After the reinforced silicone rubber, the strength can be increased up to several tens of times, the high temperature resistance and chemical resistance are also greatly improved, and the silicone rubber application field is more extensive.

Adhesive: in sealant, adhesive. It is considered as a thixotropic agent to control the precipitation of substances. It is also considered a reinforcing material. For those industrial glue methods that use high-speed production, there are special uses. It adapts the automation system to a wider range of temperature changes.

Silica in agricultural chemicals, such as pesticides, high-efficiency spray fertilizer, using silica as a carrier or diluent, disintegrant, as a disintegrant in water-dispersible granules, can improve the suspension rate, it is recommended The use content is about 10%. It maintains long-lasting effectiveness because of its extremely high surface area, high adsorption capacity, easy suspension, good affinity and chemical stability. Even in rain, wash and hot conditions, it will remain unchanged for a long time.

Paint: It is an additive that prevents pigment precipitation from acting as a stabilizer. It is usually used to change thixotropy and adjust viscosity. It is colorless and transparent in the varnish. It improves leveling in many coatings, prevents it from crusting, and affects electrostatic spraying. It also controls the gloss of some coatings, such as urethane polishing.

Polyester resin and gel layer (gel coat): Used in a large amount in polyester resins, these polyester resins are used to produce other layers such as boats and truck canopies. Reinforcing the resin in the layered resin prevents the resin from draining. In terms of the gel layer, this reinforcing effect prevents the precipitation of the substance and increases the thickness and appearance of the film layer. Thickness, flow and solubility can be controlled in putty and repair polish to suit a variety of needs.

Silica is a transparent color and opaque toothpaste for daily use as a filler and abrasive. This type of toothpaste has good flexibility and dispersibility. The paste is smooth, soft and abrasive, and does not abrade the toothpaste tube. It can make a drug toothpaste. Keep the drug stable. In particular, it has good compatibility with fluoride, which can avoid the disadvantages of calcium salts as abrasives to produce insoluble salts.

Silica anti-caking agents are used in some products to improve free-flowing properties such as grass fertilizers, fungicides, abrasive grinding agents, laundry bleaches, phenolic injections of urotropine, phenol and urea plastics, and rubber manufacturing. Sulfur and anti-caking mixture.

The paper filler made of white carbon black can improve the ink penetration resistance and mechanical strength, increase the whiteness and reduce the unit weight. It can effectively achieve paper weight reduction, reduce production costs, and improve paper performance.

It can also be used in many industries such as fire-fighting agents, feeds, cosmetics, matting agents, pigments, and paints.