There are two kinds of silica gel: one is precipitation silica gel; the other is gas phase silica gel. Fumed silica gel is resistant to high and low temperature impact, the release during vulcanization is harmless to the human body, no primer is required for bonding with various substrates, and it has excellent heat resistance, ozone resistance and chemical resistance. Fumed silica also has excellent electrical insulating properties. What is the difference between precipitation silica gel and fumed silica gel?

The difference between fumed silicone rubber products and precipitation silicone rubber products:

1. The silica gel products of the precipitation method will turn white when stretched, and the elongation rate is not good, while the silica gel products of the gas phase method are different, they will not turn white when stretched, and their elongation at break can reach the highest more than 700%.

2. The raw material cost of gas phase method silicone rubber products is higher than that of precipitation method silicone rubber products, and the tensile strength, tear strength and elongation at break of gas phase method silicone rubber products under the same hardness are better than precipitation method silicone rubber products. , and its environmental protection index is also higher.

3. The appearance of fumed silica gel products is transparent. The appearance of precipitation silicone products is opaque or translucent.

4. The gas phase method is produced by using silicon dioxide obtained by burning silicon tetrachloride and air with a fineness of more than 1000 mesh. The precipitation method is produced by using the silica precipitated by adding sulfuric acid to sodium silicate. The fineness is only 300-400 mesh.

5. The fumed silica contained in the fumed silicone rubber is expensive and not easy to absorb moisture. It is mainly a reinforcement in the rubber. Silica in precipitation silicone rubber is cheap and easy to absorb moisture. In rubber, it is mainly filling.