Abstract: Water-soluble polymers comprising N-vinyl amide such as an N-vinyl lactam are found to be useful in processes wherein the polymer is introduced into a subterranean wellbore. Polymers useful in the recovery of natural resources are prepared by polymerizing an N-vinyl lactam by free radical initiation with polymerization conducted in an aqueous solution polymerization medium preferably containing a mixture of dissolved electrolytes, or in a polymerization medium consisting essentially of a tertiary alkanol. Copolymers of such N-vinyl lactams with unsaturated amides and terpolymers prepared by polymerizing an N-vinyl lactam and an unsaturated amide with a selected termonomer compound are also useful when prepared by these methods. The invention also broadly encompasses utilizing a water-soluble polymer comprising at least one of a hydrophilic vinyl-containing sulfonate, phosphonate or ester and/or hydrophilic N-vinyl lactam for applications under hostile conditions.
Type:
Grant
Filed:
December 10, 1991
Date of Patent:
February 16, 1993
Assignee:
Phillips Petroleum Company
Inventors:
Allan Stahl, Ahmad Moradi-Araghi, John Westerman, Henry L. Hsieh, James H. Hedges, Geir Bjornson
Abstract: This invention relates to a process for preparing polysulfide product generally containing an average of 3 to 6 sulfur atoms in high yield which degrades minimally over extended time periods. Minimal degradation is accomplished by a unique treatment process wherein chemical species, most notably unreacted mercaptans and catalysts which apparently promote degradation, are selectively removed from the polysulfide crude product.
Abstract: An additive for reducing water loss from cement comprising a tetrapolymer, a base, an electrolyte, at least one surfactant, and water is disclosed. A process for producing cement slurries with improved water loss properties, as well as an improved method for cementing gas and oil well is also disclosed.
Abstract: The color and odor of n-dodecyl mercaptoethanol made using a triethylamine catalyst are improved by contacting crude n-dodecyl mercaptoethanol with a polar organic solvent having a boiling point of within about .+-.15.degree. C. of the boiling point of triethylamine and heating said components under at least a partial vacuum.