GB1088485A - Composition and process for inhibiting efflorescence in portland cement - Google Patents

Abstract

Portland cement concrete of inhibited efflorescence is made by incorporated into, or applying on the surface of, the concrete or dispersion in water of 30-70% of pinaceae heavy ends material providing units of tall oil pitch optionally extended with up to 4 parts of asphalt), mixtures of tall oil pitch and tall oil rosin (optionally extended with up to 4 parts of asphalt), or tall oil rosin extended with up to 4 parts of asphalt, said asphalt (when present) having a penetration between 250 and 500 and a softening point between 85 DEG and 140 DEG F., said dispersion also containing 0.1-5 wt. per cent, based on the heavy ends, of sodium hydroxide (or an equivalent amount of another water soluble basic compound), and 0.1-15 wt. per cent, based on the heavy ends, of protective colloid. Suitable alternative basic compounds are KOH, NH4OH, Na2CO3, sodium aluminate and triethanolamine; and suitable colloids are casein, soyabean protein, egg albumin, gum arabic, starch, gelatine, methyl cellulose, animal glue, dextrine, and sodium alginate. The dispersion may also contain a fungicide, e.g. phenyl mercury acetate or N-(3-chloroally) hexaminium chloride. The aggregate in the concrete may be expanded shale, expanded slag, limestone, sand, dolomite, crushed stone and/or gravel, and the term "concrete" includes masonry cement and conventional concrete mortar. The concrete may be coloured, e.g. by ferric oxide or ferrite yellow pigments, the dispersion of which through the concrete is enhanced by the heavy ends dispersion.