Water glass introduction
Introduction to Water Glass: Water glass, also known as sodium silicate, is a water-soluble compound that forms a viscous solution when dissolved in water. Its general chemical formula is R₂O·nSiO₂, where R₂O represents an alkali metal oxide such as sodium oxide (Na₂O), and n is the molar ratio of silica to alkali metal oxide, referred to as the modulus. In construction, the most commonly used form is sodium silicate, with the formula Na₂O·nSiO₂. Key Properties of Water Glass: Water glass is known for its strong adhesive properties, high mechanical strength, excellent resistance to acids, and good thermal stability. However, it has limited resistance to alkalis and water, which means it should be used carefully in environments where these factors are present. Physical Characteristics: It typically appears as colorless orthorhombic bipyramidal crystals or as a white to off-white powder or block. It can easily absorb moisture from the air, making it hygroscopic. When heated to 100°C, it loses up to six molecules of water. It dissolves well in water and dilute sodium hydroxide solutions but is insoluble in ethanol and acids. The melting point ranges between 40–48°C. It is considered low in toxicity, with a median lethal dose (LD₅₀) of 1280 mg/kg when ingested by rats (without crystal water). Storage Recommendations: Water glass should be stored in a sealed container in a cool, dry place to prevent moisture absorption and degradation. Applications of Water Glass: 1. Surface Treatment: Applying water glass to the surface of materials like bricks, concrete, and stone improves their durability, density, and resistance to weathering, frost, and water penetration.
2. Soil Stabilization: By alternating injections of water glass and calcium chloride into soil, a silicic acid gel forms, which helps consolidate and stabilize the ground.
3. Quick-Setting Waterproofing Agent: Water glass is often used in formulations for rapid waterproofing applications.
4. Crack Repair: A mixture of water glass, slag powder, sand, and sodium fluorosilicate can be pressed directly into cracks in brick walls to strengthen and bond them.
5. Acid-Resistant Materials: Used to make acid-resistant gels, mortars, and concretes for industrial and chemical environments.
6. Heat-Resistant Materials: Formulated into heat-resistant gels, mortars, and concrete for high-temperature applications.
7. Anti-Corrosion Applications: Used in protective coatings and systems to prevent corrosion in various structures.
8. Casting Binder: Acts as a bonding agent in foundry processes for molds and cores. Production Methods: There are two main methods for producing sodium silicate: the dry method and the wet method.
1. Dry Method: Involves mixing quartz sand and soda ash in specific proportions and heating them to around 1400°C in a furnace to produce molten sodium silicate.
2. Wet Method: Uses quartz rock powder and caustic soda, reacting them under high pressure and steam at 0.6–1.0 MPa to directly produce liquid water glass. Microsilica can also be used instead of quartz to create silicates with a higher modulus (up to 4). Main Features: Water glass offers high adhesion and strength, excellent acid resistance, and good heat resistance. However, it has poor resistance to alkalis and water, so its use must be carefully managed in certain conditions. Wifi Kinetic Remote Switch,Smart Wifi Wireless Switch,Kinetic Switch With Timer,Wireless Remote Control Switch Foshan Shunde Advante Electron Ltd. , https://www.china-advante.com