Low fluid loss cementing compositions containing hydrolyzed acrylamide/2-acrylamido-2-methylpropane sulfonic acid derivative copolymers and their use
AssigneeCalgon Corporation
InventorsLeonard J. Persinski, Michael M. Cook, Sally Lee Adams
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Abstract
Improved cementing compositions and their use in cementing operations is disclosed, wherein copolymers of hydrolyzed acrylamide and 2-acrylamido-2-methylpropane sulfonic acid derivatives are used as fluid loss additives for aqueous hydraulic cement slurries.
Claims3
A low fluid loss cement composition capable of forming a fluid slurry when mixed with water, said cement composition comprising dry hydraulic cement and from about 0.05 to about 5.0 percent by weight, based on weight of hydraulic cement on a dry basis, of a water-soluble copolymer having a molecular weight of at least 10,000, said copolymer having the formula:
- ##STR2## wherein A is independently selected from --NH.sub.2 and --.sup.-M.sup.-, provided at least 20 percent of the A groups are --.sup.-M.sup.+;
- M is hydrogen, ammonium, sodium or potassium;
- x is from about 10 to about 90 mole percent;
- and y is from about 90 to about 10 mole percent.
An hydraulic cement slurry composition comprising dry hydraulic cement;
- from about 0.05 to about 5.0 percent by weight, based on weight of hydraulic cement on a dry basis, of a water-soluble copolymer having a molecular weight of at least 10,000, said copolymer having the formula:
- ##STR3## wherein A is independently selected from --NH.sub.2 and --O.sup.-M.sup.-, provided at least 20 percent of the A groups are --O.sup.-M.sup.-;
- M is hydrogen, ammonium, sodium or potassium;
- x is from about 10 to about 90 mole percent;
- and y is from about 90 to about 10 mole percent;
- and sufficient water to form a pumpable slurry.
A method of producing an hydraulic cement aqueous slurry composition admixing together hydraulic cement, from about 0.05 to about 5.0 percent by weight, based on weight of hydraulic cement on a dry basis, of a water-soluble copolymer having a molecular weight of at least 10,000, said copolymer having the formula:
- ##STR4## wherein A is independently selected from --NH.sub.2 and --O.sup.-M.sup.+, provided at least 20 percent of the A groups are --O.sup.-M.sup.+;
- M is hydrogen, ammonium, sodium or potassium;
- x is from about 10 to about 90 mole percent;
- and y is from about 90 to about 10 mole percent;
- and sufficient water to form a pumpable slurry.
Dependencies are inferred from the claim text.