Kaolin is a mixture of inorganic non-metals.
Compared with uncalcined kaolin, calcined kaolin has less bound water content, increased silica and alumina content, increased active points, changed structure, smaller and uniform particle size, and is filled with uncalcined kaolin. Compared with the NR compound, the vulcanization characteristic curve of the low-temperature calcined kaolin filled NR compound is basically the same. The hardness of Sauer A type is unchanged and the tensile strength is improved. The physical properties of both meet the requirements of the sports shoe non-transparent sole industry standard.
The calcination process of kaolin
The production process of ultra-fine calcined kaolin mainly includes four parts: ① pre-drying of raw materials to meet the moisture requirements for ultra-fine pulverization; ② ultra-fine pulverization and classification of kaolin to achieve the required particle size for calcination; ③ high-temperature calcination to achieve the required purity Harmony whiteness; ④ After calcination, break up and disaggregate to reach the required fineness of the final product. The production process flow chart is as follows.
Paint coating, plastic and rubber grade: Kaolin raw material→water washing and impurity removal→mixing of chemicals→dry pulverization (800 mesh, 1250 mesh)→calcining→depolymerization and disintegration→product (800 mesh, 1250 mesh, 2000 mesh, 3000 mesh).
Papermaking coating grade: raw material→water washing and impurity removal→mixing of chemicals→dry grinding (2μm>80%)→calcining→mixing of dry grinding aids→depolymerization and dispersing→products (1250 mesh, 200 mesh, 3000 mesh, 2μm>70 %, 2μm>80% and some 2μm>90%).