Back to results
US 4,309,523 AGranted
Water-soluble copolymer of acrylamidomethylpropanesulfonic acids salts
AssigneeCassella Aktiengesellschaft
InventorsFriedrich Engelhardt, Ulrich Riegel, Martin Hille, Heinz Wittkus
Life of this patent
Estimating the term…
Abstract
Outstandingly suitable drilling mud additives are water soluble copolymers consisting essentially of a random distribution of (a) 5 to 95% by weight of units of the formula ##STR1## (b) 5 to 95% by weight of units of the formula ##STR2## and (c) 0 to 80% by weight of units of the formula ##STR3## wherein R.sup.1 and R.sup.2 are the same or different and each is hydrogen, methyl or ethyl; and X.sup..sym. is a cation.
Claims4
Water-soluble copolymer consisting essentially of a random distribution of
- (a) 5 to 95% by weight of units of the formula ##STR10## (b) 5 to 95% by weight of units of the formula ##STR11## and (c) 0 to 80% by weight of units of the formula ##STR12## wherein R.sup.1 and R.sup.2 are the same or different and each is hydrogen, methyl or ethyl;
- and X.sup..sym. is a cation.
Dependencies are inferred from the claim text.