The zinc rich coating is divided into two major categories of organic and inorganic.
Commonly used organic epoxy, chlorinated rubber, vinyl resin and polyurethane resin as binder, the most commonly used epoxy zinc rich coating, in which the polyamide curing zinc rich epoxy primer is organic zinc-rich primer application the largest species. Zinc is the aggregate into the paint as the expense of polar pigments and fillers and resin, fillers, solvents, and to protect the metal substrate surface, but lack the heavy anti-corrosion features to give the metal substrate surface. Therefore, based on the study of zinc-rich coating is mainly concentrated in the inorganic field.
The inorganic zinc coating is divided into the solvent and aqueous two categories. Solvent based inorganic zinc coating is a TEOS film material, The TEOS absorb moisture from the air occurred to the hydrolysis of high molecular weight oligomers, the formation of the membrane when the solvent evaporation, and continuation of the oligomer absorb moisture cross-linked to generate the polymer. Model of zinc-rich coating, solvent resistance, heat resistance, rust is worse than no model, but its steel surface quality tolerance. The best corrosion resistance in various types of zinc-rich coating for water-borne inorganic zinc-rich coating in the marine atmospheric conditions at least 25 years of service life.
Waterborne inorganic zinc coating is a silicate binder, carbon dioxide and water vapor in the air and silicate reaction of carbonate the same time, zinc silicate reaction generated silicate zinc polymer. However, due to waterborne zinc-rich coating based on water as solvent, a higher heat of vaporization of water, cause water type is slower than the models of hard work by the ambient temperature, humidity and other factors, the temperature is too low or too high will resulting in film cracking. The above problems, Jun Wang, et al. [12] must modulus 50% to 60% of the silicate solution and 15% to 20% acrylic emulsion mixed in the promotional effect of heating obtained by mixing the film substances with zinc powder and filler mixed salt spray resistance up to 2500h of coating.
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