DRY MIX FORMULATIONS CONTAINING CARBOXYLATED STYRENE-BUTADIENE REDISPERSIBLE POLYMER POWDERS AND ALUMINA RICH CONTAINING CEMENTS

摘要

Dry mix formulations containing a redispersible polymer powder (RDP) made of a low carboxylation, large particle size water-insoluble film—forming styrene butadiene polymer having at least one ethylenically unsaturated dicarboxylic acid monomer, and a high alumina content cement such as a calcium aluminate cement (CAC) or a calcium sulfoaluminate cement (CSA) provides cement compositions having unexpectedly superior water immersion shear strength and set time for a cement containing tile adhesive (CBTA or CTA), superior adhesion properties in water proofing mortars or mortar applications, and superior flexural and compressive strength in grout applications.

主权项

1. A cement containing dry mix composition comprising:
a) 0% by weight to 50% by weight of ordinary Portland cement, based upon the weight of the dry mix composition; b) a water-redispersible polymer powder (RDP) comprising a carboxylated water-insoluble film-forming styrene-butadiene polymer and a colloidal stabilizer, and c) a high alumina content cement, wherein
1) said high alumina content cement comprises from 0.5% by weight to 8% by weight of a calcium aluminate cement, based on the total weight of the dry mix composition, the calcium aluminate cement has an alumina (Al2O3) content of greater than 30% by weight, based upon the weight of the calcium aluminate cement, the amount of ordinary Portland cement is from 25% by weight to 45% by weight, based upon the total weight of the dry mix composition, and calcium sulfate is employed in an amount of from 40% by weight to 60% by weight, based upon the weight of the calcium aluminate cement, or2) said high alumina content cement comprises from 30% by weight to 50% by weight of a calcium sulfoaluminate cement, based on the total weight of the dry mix composition, and the amount of ordinary Portland cement is from 0% by weight to 50% by weight, based upon the total weight of the dry mix composition, or3) said high alumina content cement comprises from 0.5% by weight to 8% by weight of a calcium aluminate cement, based on the total weight of the dry mix composition, the calcium aluminate cement has an alumina (Al2O3) content of greater than 55% by weight, based upon the weight of the calcium aluminate cement, and the amount of ordinary Portland cement is from 25% by weight to 45% by weight, based upon the total weight of the dry mix composition.