Water glass binder

Also including the water-glass binder, the general formation of these inorganic polymer binders appears in a similar way, starting with any at least silicate containing solid from an industrial or natural origin. 

H.-D. Zellmann and Ch. Kaps, Chemically modified Water Glass Binders for Acid-resistance Molars,y. Amer. Ceram. Soc., 89, 1369-1372 (2006). 

Dense, spherical particles with smooth surfaces and diameters of 20 p,m or greater provide the optimal flow behavior. The presence of more than 5% fines (particles less than about 20 fim in diameter) may prohibit flow altogether. Binders and other additives can inhibit proper flow when the temperature exceeds the glass transition point of the additive, and relative humidity cau affect the flow behavior of water-soluble binders. 

Potassium-silicate water glass is manufactured for special purposes (e.g. binder for acid-resistant cements, fresco paintings, etc.). The application of soluble silicates in industry is dealt with in the monograph by Vail (1952). 

Potassium water glass solutions are mainly utilized in the production of coatings for welding electrodes, as binders for luminescent pigments used in cathode ray tubes, for impregnating walls and as a binder for plasters. 

The expression water glass paints is understood to mean coating systems based on the binder water glass (potassium, sodium, or occasionally, lithium water glass). The general expression silicate coatings has been adopted for these systems and is therefore used throughout Section 2.15.1. 

Properties, The special properties of silicate paints are imparted by the binder, generally potassium water glass. The paint coats harden physically by evaporation of water, as well as chemically by several reactions. These stabilization and consolidation processes are termed silicification [2.176]. The water glass reacts as follows with atmospheric carbon dioxide ... 

The application of water glass sand as a binder has a low environmental impact, compared to the application of organic binders. This technique allows the (partial) regeneration of the water glass bonded sand and thus reduces the need for used sand disposal and primary raw material... 

In alkali silicate binders the setting and hardening is based on a reaction between a water glass (a solution of an alkali silicate in water) and alkali fluosilicate (see also section 15.3). The reaction product is an amorphous form of Si02 with embedded ciystals of alkah fluoride. The amorphous Si02 remains preserved until about 550°C and converts gradually to quartz and tridimite at higher temperatures. At 750°C crystalline sodium disilicate starts to be formed. 

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