Silicate paints composition

Although there are many varieties of paint in use, Haynie (6) has chosen to simplify them into two types according to the composition of the extender, or thickener. Of the two paint types, the more pollutant-resistant contains silicate extenders while older, carbonate extender paints are less pollutant-resistant. Silicate extender paints have become dominant in the exterior paint market only in the last decade, accounting for most (probably over 80 percent) of current sales. The proportion of silicate paint on buildings is unknown, however, but is conservatively assuned to be 85 percent. The switch to silicate paints may have occurred partially as a result of concern with the ervironmental susceptibility of the carbonate extender paints. Tliese substitution costs are not factored into the damage estimates provided in this analysis. 

Chem. Descrip. Vinyl acetate/ethylene/vinyl ester terpolymer disp. with protective colloid (cellulose derivs.), surfactant emulsifier Uses Binder for syn. resin-bound plaster and exterior thermal insulation composite systems, low-odor interior emulsion paints, interior/exterior masonry coatings, silicate paints... 

Talc is the magnesium silicate structural analog to pyrophyllite. Its properties are nearly identical to pyrophyllite, except that Al3+ cations have been replaced by Mg2+ cations [25], Talc occurs in secondary deposits and is formed by the weathering of magnesium silicate minerals such as olivine and pyroxene [2], In bulk form, talc is also called soapstone and steatite. A typical composition for talc is given in Table 7 [22], Historically, talc has been used extensively in electrical insulator applications, in paints, and as talcum powder [2],... 

Vail (1) has extensively reviewed the practical aspects of precipitated metal silicates. In the case of magnesium silicates, which are used as adsorbents, decolorizing agents, catalysts, and fillers in paints and also for treating stomach ulcers, the composition may be varied within wide limits. The strong tendency for magnesium hydroxide to react with silica (even in the monomeric state) is shown by the fact that the addition of 300 ppm Mg(OH)j to water will reduce the soluble silica content from 42 to O.rppm. 

Basic Lead Silicate n 3 PbO-2 S102-H20. Pigment White 16 (77625). Pigment consisting of an adherent surface layer of basic lead silicate cemented to silica. Compositions and constants vary depending on commercial grade. (Gooch JW (1993) Lead based paint handbook. Plenum, New York). 

Talc is used in the ceramic, paper, plastics, rubber, building, paint, and cosmetic industries. Mineralog-ically, talc is a pure hydrous magnesium silicate with an ideal chemical composition of 63.5% SiOj, 31.7%... 

Ceramic and/or glass-like coatings can be formed by heating the silicate pastes painted onto the itmer wall of the tubes. These coatings can completely cover the metallic surfaces and then decrease the probability of formation of coke deposits. The main composition of the coating is K2O, Si02 and AI2O3, etc. 

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