Cement admixture product having improved rheological properties and process of forming same
AssigneeW. R. Grace & Co.-Conn.
InventorsDavid Charles Darwin, Ellis Martin Gartner, Byong-Wa Chun, Hideo Koyata, Lawrence Lu Kuo
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Abstract
The present invention is directed to an imidized polycarboxylic acid polymer useful as a cement admixture, to improved cement compositions containing said polymer and to a process of forming the same.
Claims7
A process of forming an imidized polymer comprising contacting (i) a polymer having functional groups selected from carboxylic acid groups, their C.sub.1 -C.sub.10 alkyl esters, or mixtures thereof, wherein said functional groups are positioned pendant alpha-beta, alpha-gamma or both from the polymer backbone chain with (ii) an amine selected from ammonia, or a primary amine of the formula
- H.sub.2 N(BO).sub.n R"
- wherein O represents oxygen atom, B represents a C.sub.2 -C.sub.10 alkylene group, R" represents a C.sub.1 -C.sub.10 alkyl group, and n represents an integer of 1 to 200;
- maintaining said reaction mixture at a temperature of from 60.degree. to 250.degree. C. at atmospheric or reduced atmospheric pressure for a time of from 1 to 8 hours while removing water from the reaction mixture;
- and cooling and recovering the formed imidized polymer product.
Dependencies are inferred from the claim text.