Application of nanoscale boehmite sol in chromium-free passivation of aluminum

In many cases, the nanoscale Boehmite sol film has better performance than the phosphate or chromate film currently used. Experiments show that the film has good adhesion properties to various polymers, such as paint, synthetic rubber and binders, in addition to its anti-corrosion effect.

When the viscosity of Boehmite sol is lower than 5.6mPa/s and the particle size of Boehmite sol is less than 100nm, the dry bonding force between the sol coating and the paint film is qualified. Therefore, in the aluminum surface treatment, the aluminum and aluminum alloy soaked by nano-boehmite sol can form nano-boehmite film on the surface, which is used as the chemical conversion layer of aluminum alloy spraying pretreatment, replacing the chromate and phosphate-chromate chemical oxidation film widely used in the current aluminum alloy coating pretreatment. It has become a new chromium-free passivation process with lower cost, green environmental protection, zero sewage discharge, simple and stable production operation, excellent adhesion and corrosion resistance, and has broad market prospects.

The company specializes in the production and development of nano-Boehmite sol powder, the particle size of the material nanoparticles is small, the diameter of the nanorods is less than 5nm, the specific surface area of the product is large (about 250 m2/g), and the acidity (pH value 4-5) is between, which solves the release of acidic gas in the use of aluminum sol. The nanoparticles are uniformly dispersed, transparent, and stable for a long time without agglomeration. It has the characteristics of small nanoparticle, high transparency, adhesiveness, thixotropy, easy dispersion, reversibility of water solubility, suspension, positive charge, adsorption, stability, etc., and has a wide range of applications.

The main application areas are:

1. Using the adhesive property, film forming property and wear resistance of aluminum sol, it can be used as a bonding agent for inorganic fibers such as glass fiber, asbestos, ceramic fiber, and form any shape.

2. Ceramic paper can be made with aluminum sol and silicate glue fiber.

3. With aluminum sol and refractory powder or inorganic fiber mixed, can be made of any viscosity of heat-resistant coating materials, cast refractory materials and spraying materials.

4. Added to the manufacturing of ceramic utensils can increase the strength of green, can be made into a variety of ceramic products.

5. In textile fibers, it can increase the smoothness, improve the impact resistance and improve the wear resistance.

6. Used in the paper industry, it can improve the smoothness, whiteness and humidity resistance of paper, and can also be used as a adhesive for processing paper surface treatment.

7. Can be used as cationic emulsifier.

8. Can be used to prepare catalyst carrier or molecular sieve.

9. Can be used for transparent coating, fluorescent lamp coating, lamp glue coating.

10. Add to a variety of acrylic, polyurethane, epoxy, melamine, silicone acrylic emulsion and other coatings to improve strength and hardness.

11.  It can be widely used in petrochemical catalyst, aluminum silicate fiber and ceramics and other high temperature resistance, refractory forming binder, ceramic enamel additive, anti-static agent for velvet and electrostatic weaving flocking, film forming agent and anti-static agent for textile and fiber product treatment, precision casting alumina casting, emulsifier and stabilizer for pigment and coating, photo paper surface treatment agent, greenhouse Antifogging agent, waterproofing agent, etc., can also be used in inorganic fiber, activated alumina, high purity alumina, enamel, daily necessities, paper and other industries.