Water-soluble antifoam additive for a cement composition, aqueous solution containing same and use thereof in mortars or concretes
AssigneeCiments Francais
InventorsSoraya Mehalebi, Anne-Elisabeth Desmotz
Life of this patent
Estimating the term…
Abstract
An anti-foam additive for a cement composition, including a fatty alcohol ester that is soluble in an aqueous medium at acidic pH, and hydrolysable in a basic medium, i.e. when the ester is incorporated into the cement composition, while releasing an active anti-foam molecule. This ester is preferably a fatty alcohol ester of a quaternary ammonium carboxylate, that is soluble in an aqueous solution of a superplasticizer, such as a polycarboxylate with poly(ethylene oxide) side chains. The additive can used for reducing the amount of air entrained during mixing or blending of mortars or concretes.
Claims13
An aqueous solution of superplasticizer for a cementitious composition, comprising:
- at least one superplasticizer selected from the groupconsisting of polycarboxylates with polyethylene oxide side chains and poly(meth)acrylates with polyethylene oxide side chains, and at least one anti-foam additive in the form of a fatty alcohol ester that is soluble in an aqueous medium at acid pH and hydrolysable during incorporation into said cementitious composition, capable of releasing said fatty alcohol, the fatty alcohol being an active anti-foam molecule, the superplasticizer and the anti-foam additive being dissolved in said aqueous solution.
A mortar or concrete, comprising:
- cement;
- water;
- superplasticizer selected from the group consisting of lignosulfonates and polycarbonates with polyethylene oxide side chains;
- and
- an anti-foam additive in the form of a fatty alcohol ester that is soluble in an aqueous medium at acidic pH and hydrolysable during incorporation into said cement that releases said fatty alcohol, the fatty alcohol being an active anti-foam molecule, the fatty alcohol ester being a fatty alcohol ester of a quaternary ammonium carboxylate, of general formula (I) below:
- A-, R1R2R3N+CH2C(0)OR4 (I)
- where the radicals R1, R2 and R3, which are identical or different, are radicals selected from the group consisting of hydrogen, substituted or unsubstituted, linear or branched C1 to C12 alkyl radicals, and R4 is a saturated or unsaturated, substituted or unsubstituted, linear or branched C10 to C22 fatty alcohol hydrocarbon chain, A is a sulfonate anion,
- the anti-foam additive being present in an amount effective to reduce an amount of air entrained during mixing and blending of the mortar or concrete.
Dependencies are inferred from the claim text.