GUM ROSIN SALT AIR-ENTRAINING HYDRAULIC CEMENT ADMIXTURE, METHOD OF ITS USE AND HYDRAULIC CEMENT COMPOSITIONS CONTAINING SAME

摘要

An air-entrainer ('AE') admixture, method of entraining air, and cement compositions containing the admixture. The AEs are obtained by saponification of gum rosin, typically obtained from the group of trees consisting of pinus elliotti, pinus taeda, pinus caribaea, pinus palustris, pinus ponderosa, pinus halepensis, pinus brutia, pinus pinaster and pinus peuce, and comprise alkaline earth metal, aliphatic amine, alkanolamine, or alkali metal salts of gum rosin acids comprising a) from about 8 to 55 % by weight abietic acid, based on the total weight of said gum rosin acids in said AE; b) from about 0 to 35 % isopimaric acid; c) from about 0 to 15 % pimaric acid; and d) from about 10 to 65 % levo-pimaric acid. The admixtures of the invention, and the method for using them, provide air entrainment comparable to Vinsol rosin AEs at a lower dosage, greater stability of the air content in plastic concrete during mixing, lower spacing of air and fast buildup of air in low-slump concretes.