GB938567A - Improved cementitious compositions - Google Patents

Abstract

A dry cementitious composition comprises by weight, 100 parts hydraulic cement e.g. Portland cement, 50-300 parts merit powdered filler, 1 to 3 parts accelerator, and 1 to 10 parts of a water soluble vinyl alcohol polymer such a polyvinyl alcohol. The composition may also contain in parts by weight per 100 parts of cement, 1 to 30 parts of pozzolano such as volcanic ash, peccolo, slags, fly ash and silico fluorides, 1 to 8 parts stearates e.g. butyl stearate, 0,5 to 5 parts of a dispensing agent such as a tertiary amine, a sulphosuccinate, an alkyl aryl sulphonate, an ethylene oxide fatty acid condensate, an aryl alkyl alcohol or a polyoxyalkylene compound, 0,7 to 3 parts of a silicone such as sodium methyl siliconate, and 1 to 20 parts of an extender such as alkali metal silicates, talc, titanium dioxide, calcium silicates, microns, silica, calcium carbonate, aluminium silicate, and magnesium silicate. Up to 60 parts per 100 parts of the alcohol of a plasticizer such as a phosphoric acid ester, glycerin formamide, the lower glycols and hydroxylated amides, and 0,2 to 3 parts of borax per 100 parts alcohol may also be added. The acceleration is a water soluble alkali metal or alkali earth metal halide and the fillers which have a particle size less than 1/4 inch are paint pigments, stone, gravel, clays, sand, shale, slate and marble. Water is added to the dry powdered mixture to form an aqueous dispension which can be air cured and can adhere to metal substrates.