Sodium silicate is a water-soluble silicate. The main reason is that the glass bottle containing NaOH solution contains SiO? , formed by interaction, has a strong viscosity, soluble in water, generally speaking, in the case of water as a solvent, all sodium salts are soluble, except a few lithium salts (such as Li? CO？ ) The rest is soluble.
After coating or impregnating the material with water glass solution, it can penetrate into cracks and pores, and the cured silica gel can block capillary channels, improve the density and strength of the material, and thus improve the weather resistance of the material. However, sodium silicate should not be used for painting or impregnating gypsum products. Because sodium silicate reacts with gypsum to produce sodium sulfate (Na? So what? ), the crystals expand in the pores of the products, leading to cracking and damage of gypsum products.
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Use of sodium silicate
1. Brush the material surface with density 1.35g/cm to improve its weatherability? Soaking or brushing porous materials such as clay brick, cement concrete, silicate concrete and stone with sodium silicate can improve the compactness, strength, impermeability, frost resistance and water resistance of materials.
2. By alternately injecting sodium silicate and calcium chloride solution into the soil to reinforce the soil, the generated silicic acid gel will reinforce the soil in a humid environment because it absorbs the moisture in the soil.
3. Prepare quick-setting waterproof agent.
4. Repairing cracks in brick walls After mixing sodium silicate, granulated blast furnace slag powder, sand and sodium fluorosilicate in a proper proportion, they are directly pressed into cracks in brick walls, which can play a role in bonding and strengthening.
5. Sodium silicate aqueous solution can be used as the external surface of fire doors.
6. It can be used to make acid-resistant mastic, and used for lining of furnaces and mines. Physical and chemical properties.
7. Preparation of silica gel.
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