Gypsum-free cement compositions
AssigneeW. R. Grace & Co.
InventorsFrank G. Serafin, Robert W. Previte, Nathan R. Greening, David L. Kantro, Fulvio J. Tang
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Abstract
Disclosed herein are gypsum-free cement compositions comprising portland cement, limestone and an amine salt of formic or acetic acid. The compositions exhibit compressive strength comparable to ordinary portland cement compositions containing gypsum and the setting properties of the compositions can be regulated.
Claims17
A gypsum-free cement composition exhibiting a compressive strength comparable to ordinary portland cement containing gypsum, and with setting properties which can be regulated, said composition comprising a portland cement clinker having from 1 to 10 weight % of limestone interground therewith to exhibit a specific surface area of from 3000 to 7000 cm.sup.2 /g, and a water-soluble amine salt in an amount of from 0.005 to 1% by weight of said clinker, said salt formed by reaction between an amine and formic or acetic acid.
A method of making a gypsum-free cement composition exhibiting compressive strength comparable to ordinary portland cement containing gypsum and with setting properties which can be regulated, said method comprising intergrinding portland cement clinker in the presence of from 1 to 10% by weight of limestone to provide a cement having a specific surface area of from 3000 to 7000 cm.sup.2 /g and controlling the setting time of said composition by incorporating therein a water-soluble amine salt in an amount of from 0.05 to 1% by weight of said clinker, said salt formed by reaction between an amine and formic or acetic acid.
A settable portland cement composition exhibiting compressive strength comparable to ordinary portland cement containing gypsum, and with setting properties which can be regulated, said composition comprising water, an inert aggregate, a portland cement clinker having from 1 to 10% by weight of limestone interground therewith to exhibit a specific surface area of from 3000 to 7000 cm.sup.2 /g, and a water-soluble amine salt in an amount of from 0.005 to 1% by weight of said clinker, said salt formed by reaction between an amine and formic or acetic acid.
Dependencies are inferred from the claim text.