# US 12,110,451 B2 · Methods and materials for controlled release of materials in a subterranean reservoir > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,110,451 B2 - Document ID: US12110451B2 - Status: Granted - Kind: B2 - Application number: 17/355,828 - Filed: 2021-06-23 - Published: 2021-10-14 - Granted: 2024-10-08 - Earliest claimed: 2016-06-27 - Assignees: Research Triangle Institute - Applicants: Research Triangle Institute - Inventors: Leah Marie Johnson; Ginger Denison Rothrock; Chasity Antoninette Norton; Nicolas Daniel Huffman; Jeffrey Brent Mecham - Web page: https://patentgrep.com/patent/US12110451B2 ## CPC - C09K 8/588: characterised by the use of specific polymers {(polymeric surfactants C09K8/584)} - C09K 8/508: macromolecular compounds {(C09K8/512 takes precedence)} - C09K 8/512: containing cross-linking agents - C09K 8/516: characterised by their form or by the form of their components, e.g. encapsulated material - E21B 33/138: Plastering the borehole wall; Injecting into the formation - E21B 43/20: Displacing by water - C09K 2208/10: Nanoparticle-containing well treatment fluids - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract The present disclosure relates to delivery and release systems, such as core-shell particles. An exemplary composition according to the disclosure can include a degradable polymeric shell surrounding a core that includes a crosslinker, which can encompass a metal, such as chromium. The core-shell particles can be provided with a gel-forming polymer, such as a polyacrylamide, into a subterranean reservoir having conditions such that the shell of the core-shell polymer degrades, and the so-released metal is effective to at least partially crosslink the gel-forming polymer to form a gel. The so-formed gel can be effective to control water flow through the subterranean reservoir, such as in relation to a waterflood of the reservoir. ## Claims ### Claim 1 A controlled-release delivery particle comprising: an outer shell defining an interior core, the outer shell being at least partially formed of a degradable polymer selected from the group consisting of polyureas, polyurethanes, and combinations thereof; and one or more materials present in the interior core and releasable from the controlled-release delivery particle; wherein the controlled-release delivery particle has an average size of about 50 nm to about 900 nm; and wherein the controlled-release delivery particle is configured for delivery to a site of use exhibiting one or more conditions effective to cause the outer shell to degrade from the outside-in and release the one or more materials from the interior core, the one or more conditions effective to cause the outer shell to degrade comprising one or more of pH, temperature, pressure, salinity, shear, and oil content. ### Claim 2 (depends on 1) The controlled-release delivery particle of claim 1, wherein the outer shell is configured for one or more of thermal degradation, oxidative degradation, and chemical degradation. ### Claim 3 (depends on 1) The controlled-release delivery particle of claim 1, wherein the outer shell includes one or more of: one or more polymers with hydrolytically cleavable groups that degrade with time; one or more polymers with hydrolytically degradable groups that degrade in aqueous media; one or more polymers with azo cleavable groups; and one or more polymers with thermally degradable azo groups. ### Claim 4 (depends on 1) The controlled-release delivery particle of claim 1, wherein the one or more materials present in the interior core includes one or more materials useful for release in a subterranean reservoir for hydrocarbon deposits. ### Claim 5 (depends on 1) The controlled-release delivery particle of claim 1, wherein the one or more materials present in the interior core includes one or more crosslinkers for a gel-forming polymer. ### Claim 6 (depends on 1) The controlled-release delivery particle of claim 1, wherein the one or more materials present in the interior core includes one or more wettability modifiers. ### Claim 7 (depends on 1) The controlled-release delivery particle of claim 1, wherein the one or more materials present in the interior core includes one or more anti-scale agents. ### Claim 8 (depends on 1) The controlled-release delivery particle of claim 1, wherein the one or more materials present in the interior core includes one or more surfactants. ### Claim 9 (depends on 1) The controlled-release delivery particle of claim 1, wherein the one or more materials present in the interior core includes one or more catalysts. ### Claim 10 (depends on 1) The controlled-release delivery particle of claim 1, wherein the one or more materials present in the interior core includes one or more blocking agents. ### Claim 11 (depends on 1) The controlled-release delivery particle of claim 1, wherein the one or more materials present in the interior core includes one or more sensors. ### Claim 12 (depends on 1) The controlled-release delivery particle of claim 1, wherein the outer shell is configured for delayed release of the one or more materials present in the interior core. ### Claim 13 (depends on 1) A system comprising a plurality of a controlled-release delivery particle according to claim 1 in combination with a liquid medium so that the system is configured for delivery to a placement site. ### Claim 14 (depends on 13) The system of claim 13, wherein the medium is a hydrating medium. ### Claim 15 (depends on 13) The system of claim 13, wherein the hydrating medium comprises freshwater or brine. ### Claim 16 (depends on 13) The system of claim 13, wherein the medium is a polymer solution. ### Claim 17 (depends on 16) The system of claim 16, wherein the polymer solution includes a gel-forming polymer. ### Claim 18 (depends on 16) The system of claim 16, wherein the polymer solution includes a polymer having a molecular weight of about 50,000 Da to about 2,000,000 Da. ### Claim 19 (depends on 13) The system of claim 13, wherein the system is configured for pumping through a line to the placement site.