# US 8,772,203 B2 · Polymeric gel system and methods for making and using same in hydrocarbon recovery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,772,203 B2 - Document ID: US8772203B2 - Status: Granted - Kind: B2 - Application number: 13/606,251 - Filed: 2012-09-07 - Published: 2012-12-27 - Granted: 2014-07-08 - Earliest claimed: 2002-08-27 - Assignees: Clearwater International, LLC - Applicants: Kevin M. Schwartz - Inventors: Kevin M. Schwartz - Web page: https://patentgrep.com/patent/US8772203B2 ## CPC - C09K 8/12: containing synthetic organic macromolecular compounds or their precursors - B08B 9/0555: {Gelled or degradable pigs} - C09K 8/24: Polymers - C09K 8/38: Gaseous or foamed well-drilling compositions - C09K 8/40: Spacer compositions, e.g. compositions used to separate well-drilling from cementing masses - C09K 8/602: {containing surfactants} - C09K 8/665: {containing inorganic compounds (proppants C09K8/80)} - C09K 8/68: containing organic compounds - C09K 8/703: {Foams} - C09K 8/882: {obtained by reactions only involving carbon-to-carbon unsaturated bonds} - E21B 17/1064: {Pipes or rods with a relatively rotating sleeve} - F17D 3/08: the different products being separated by "go-devils", e.g. spheres (cleaning devices moved along inside a pipe-lines by fluid pressure B08B9/04; {pigs or moles per se, their launching and detection F16L55/26}) - C09K 2208/26: Gel breakers other than bacteria or enzymes - C09K 2208/28: Friction or drag reducing additives - C09K 2208/30: Viscoelastic surfactants [VES] - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - B08B: CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - F17D: PIPE-LINE SYSTEMS; PIPE-LINES (pumps or compressors F04; fluid dynamics F15D; valves or the like F16K; pipes, laying pipes, supports, joints, branches, repairing, work on the entire line, accessories F16L; steam traps or the like F16T; fluid-pressure electric cables H01B9/06) ## Abstract Coacervate gels having excellent shear viscosities and other properties are made with anionic or cationic polymers, a smaller amount of a surfactant having a charge opposite that of the polymer, and a hydrophobic alcohol and an effective amount of a phosphorus-containing compound sufficient to increase the viscosity of coacervate gels up to 3 times as compared to the gels in the absence of the phosphorus-containing compound. The Zeta Potential of the gel is maintained at an absolute value of at least 20. Optional gel promoting additives include betaines and amine oxides. A preferred gel comprises poly diallyl dimethyl ammonium chloride, a lesser amount of sodium lauryl sulfonate, and lauryl alcohol. The gels are particularly useful in well drilling fluids and well fracturing fluids. ## Claims ### Claim 1 An aqueous gel comprising: a water-soluble cationic polymer in an amount no greater than 1% by weight, an anionic surfactant in an amount less than that of the polymer, and a phosphorus-containing compound in an effective amount between about 0.001 wt % and about 10 wt. %, where the phosphorous-containing compound is selected from the group consisting of mono-alkali metal phosphate (PO(OH)(OM), where M is Li, Na, K, Rd, or Cs, di-alkali metal phosphate (PO(OH)(OM)2, where each M is the same or different and is Li, Na, K, Rd, or Cs, tri-alkali metal phosphate (PO(OM)3, where each M is the same or different and is Li, Na, K, Rd, or Cs, carbyl phosphate (PO(OR)(OM)2, where R is a carbyl group and each M is H, Li, Na, K, Rd, or Cs, dicarbyl phosphate (PO(OR1)(OR2)(OM), where R1 and R2 are the same or different carbyl groups and M is H, Li, Na, K, Rd, or Cs, tricarbyl phosphate (PO(OR1)(OR2)(OR3), where R1, R2, and R3 are the same or different carbyl groups, or mixtures or combinations thereof, where the polymer and the anionic surfactant form a coacervate gel and where the effective amount is sufficient to increase a gel viscosity of the composition, increase a viscosity build up of the composition, and increase gel stability of the composition and where the composition is characterized in that the composition has a zero shear viscosity of at least 45,000 or a settling rate of no more than 8 millimeters measured by adding 10 mL of 20/40proppant to 100 mL of a 1.1 wt. % gel maintained at 80° C. in a 100 mL graduated cylinder and measuring a depth in millimeters of the gel from a top of the graduated cylinder. ### Claim 2 (depends on 1) The gel of claim 1, wherein the water-soluble polymer is present in the gel in an amount no greater than 0.7%. ### Claim 3 (depends on 2) A well treatment fluid comprising a proppant and a gel of claim 2. ### Claim 4 (depends on 1) The gel of claim 1, further a hydrophobic alcohol. ### Claim 5 (depends on 4) The gel of claim 4, further comprising: a gel promoter comprising one or more of an amphoteric surfactant and/or an amine oxide surfactant, while maintaining a Zeta Potential value greater than or equal to 20 millivolts or less than or equal to -20 millivolts. ### Claim 6 (depends on 1) The gel of claim 1, wherein the phosphorus-containing compound in an amount between about 0.05 wt. % and about 3 wt. %. ### Claim 7 (depends on 1) The gel of claim 1, wherein the effective amount of the phosphorus-containing compound is between about 0.05 wt. % and about 1 wt. %. ### Claim 8 (depends on 1) The gel of claim 1, further comprising: a gel promoter comprising one or more of an amphoteric surfactant and/or an amine oxide surfactant, while maintaining a Zeta Potential value greater than or equal to 20 millivolts or less than or equal to -20 millivolts. ### Claim 9 (depends on 1) The gel of claim 1, wherein the phosphorous-containing compound comprises tricarbyl phosphate (PO(OR1)(OR2)(OR3), where R1, R2, and R3 are the same or different carbyl groups, or a mixture of tricarbyl phosphates. ### Claim 10 (depends on 1) The gel of claim 1, wherein the R1, R2, and R3 groups are the same or different the alkyl groups having from about 4 to about 12 carbon atoms.