Low shrinkage cement composition
AssigneeW. R. Grace & Co.-Conn.
InventorsBaha E. I. Abdelrazig, Ellis M. Gartner, David F. Myers
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Abstract
The present invention is directed to a cement admixture and the resultant cement composition capable of inhibiting drying shrinkage and crack formation resulting therefrom.
Claims18
A cement admixture comprising at least one compound of the Formula I:
- ##STR3## wherein R.sub.1 represents a C.sub.4 -C.sub.6 alkyl group, X represents an oxygen atom or a secondary nitrogen group (--NH--), and R.sub.2 represents a hydrogen atom or a C.sub.1 -C.sub.3 alkyl group when X is a secondary amine, or R.sub.2 represents a primary nitrogen group (--NH.sub.2) or a --CH.sub.2 C(O)CH.sub.3 group when X is an oxygen atom;
- and at least one cement water reducing agent.
An improved cement powder composition comprising from 99 to 90 weight percent of a cement powder selected from a portland cement, blended cement or aluminous cement and substantially uniformly dispersed therein from 0.1 to 10 weight percent of at least one compound of Formula I:
- ##STR4## wherein R.sub.1 represents a C.sub.4 -C.sub.6 alkyl group, X represents an oxygen atom or a secondary nitrogen group (--NH--), and R.sub.2 represents a hydrogen atom or C.sub.1 -C.sub.3 alkyl group when X is a secondary nitrogen group or R.sub.2 represents a primary nitrogen group (--NH.sub.2) or a --CH.sub.2 C(O)CH.sub.3 group when X is an oxygen atom.
An improved concrete composition comprising cement, sand, aggregate and water and having substantially uniformly dispersed therein from 0.I to 10 weight percent based on the cement of at least one compound of the Formula I:
- ##STR5## wherein R.sub.1 represents a C.sub.4 -C.sub.6 alkyl group, X represents an oxygen atom or a secondary nitrogen group (--NH--), and R.sub.2 represents a hydrogen atom or C.sub.1 -C.sub.3 alkyl group when X is a secondary amine, or R.sub.2 represents a primary nitrogen group (--NH.sub.2) or --CH.sub.2 C(O)CH.sub.3 group when X is an oxygen atom.
Dependencies are inferred from the claim text.