Polymeric pyrrolidinium methanesulfonate viscosifiers for aqueous fluids
AssigneeMobil Oil Corporation
InventorKirk D. Schmitt
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Abstract
There are provided polymeric pyrrolidinium methanesulfonate viscosifiers which are useful in chemical waterflooding and in drilling fluids. These compounds may be formed by an unexpected cyclization reaction of quaternary diallyl amino groups on polymeric backbones involving the reaction of such groups with bisulfite salts.
Claims21
An aqueous fluid for use as either (a) a mobility control fluid in the secondary or tertiary recovery of oil or (b) a drilling fluid in the drilling of subterranean wells, said fluid having a salinity of at least 5 weight percent and comprising a salt of a polymeric sulfonate which comprises a polymeric polyvinyl alcohol backbone having side chain groups of the formula ##STR11## where:
- (i) R.sub.1 is CH.sub.3, CH.sub.2 CH.sub.3, CH.sub.2 CH.sub.2 OH, propyl, butyl or phenyl;
- (ii) R.sub.2 is (CH.sub.2).sub.n or ##STR12## and (iii) n is 1-5,
- the salt being present in the fluid in an amount sufficient to thicken thhe fluid.
In a method of recovering oil from a subterranean oil reservoir penetrated by spaced injection and production systems in which an aqueous mobility control slug is introduced into said reservoir through said injection system to displace oil to said production system, an improvement comprising employing in said slug a thickening amount of a polymeric sulfonate which comprises a polymeric polyvinyl alcohol backbone having side chain groups of the formula ##STR13## where:
- (i) R.sub.1 is CH.sub.3, CH.sub.2 CH.sub.3, CH.sub.2 CH.sub.2 OH, propyl, butyl or phenyl;
- (ii) R.sub.2 is (CH.sub.2).sub.n or ##STR14## and (iii) n is 1-5.
A method for maintaining the proper viscosity of an aqueous brine drilling fluid, said method comprising incorporating into said fluid a viscosity increasing amount of a polymeric sulfonate which comprises a polymeric polyvinyl alcohol backbone having side chain groups of the formula ##STR15## where:
- (i) R.sub.1 is CH.sub.3, CH.sub.2 CH.sub.3, CH.sub.2 CH.sub.2 OH, propyl, butyl or phenyl;
- (ii) R.sub.2 is (CH.sub.2).sub.n or ##STR16## and (iii) n is 1-5.
Dependencies are inferred from the claim text.