Aluminum tripolyphosphate (ADP), an inorganic fine chemical, possesses advantages such as non-toxicity, good storage stability, and excellent weather resistance. It is a new generation of environmentally friendly rust-preventive pigments that can be mixed with alkyd resins, phenolic resins, epoxy resins, epoxy polyesters, acrylic-melamine resins, styrene-acrylic emulsions, silicone resins, polyaniline resins, polyvinyl chloride, chlorinated polyethylene, and chlorinated rubber. In the coatings industry, it is used to prepare rust-preventive coatings, zinc-rich primers, thick-film coatings, powder coatings, organotitanium anti-corrosion coatings, rust-resistant coatings, fire-retardant coatings, heat-resistant coatings, and water-based coatings. Colors can be freely customized, and its rust-preventive performance is superior to materials such as red lead, zinc chrome yellow, zinc phosphate, and zinc molybdate. Its excellent performance has made it highly favored by users. Furthermore, its applications in adsorbents, ion exchangers, refractory materials, inorganic molding materials, and catalysts have also received widespread attention.
Aluminum oxide and phosphorus pentoxide (orthophosphoric acid or ammonium dihydrogen phosphate) are stirred and reacted at 100~200 to produce aluminum orthophosphate with appropriate ratios. Aluminum orthophosphate in the high temperature furnace dehydration polymerization reaction, the structure of the product with the polymerization temperature, polymerization time and material environment atmosphere is different and varies greatly. In order to produce high purity AlH2P3O10-2H2O type products, the polymerization conditions are generally controlled as follows: polymerization temperature of 250-400 , polymerization time of 3-24 h. The late polymerization should be passed into the water vapor to make it become dihydrate. When making pigment, AlH2P3O10-2H2O should be modified with silicon and zinc treatment agent. The treatment agent is generally silicic acid and zinc salt. The treated product is washed, dried, crushed and graded, and the final product is aluminum triphosphate dihydrogen pigment.
