REDISPERSIBLE POLYMER POWDER MIXTURES FOR USE IN DRY-MIX FORMULATIONS

摘要

A mixture of first and second redispersible polymer powders where the first redispersible polymer powder has a copolymer having a glass transition temperature of 60 degrees Celsius or higher and an acid level in a range of 0.1 to 8 weight-percent percent as determined by potentiometric titration according to ASTM D664 and the second redispersible polymer powder is selected from vinyl acetate ethylene copolymer redispersible polymer powders and polymer powders of a blend of vinyl acetate ethylene copolymer and vinyl ester of versatic acid copolymer is useful as a component in a dry-mix formulation that further contains Portland cement, alumina rich cement and calcium sulfate.