# US 9,518,156 B2 · Methods of preparing metal nanodendrimer structures > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,518,156 B2 - Document ID: US9518156B2 - Status: Granted - Kind: B2 - Application number: 14/604,560 - Filed: 2015-01-23 - Published: 2016-07-28 - Granted: 2016-12-13 - Earliest claimed: 2015-01-23 - Assignees: Xerox Corporation - Applicants: Xerox Corporation - Inventors: Valerie M. Farrugia; Alana Desouza; Sandra J. Gardner - Web page: https://patentgrep.com/patent/US9518156B2 ## CPC - C08J 3/212: {and solid additives} - C08K 3/08: Metals - C08K 3/28: Nitrogen-containing compounds - C08J 2367/02: Polyesters derived from dicarboxylic acids and dihydroxy compounds; (C08J2367/06 takes precedence) - C08K 2003/0806: {Silver} - C08K 2201/011: Nanostructured additives - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) ## Abstract A method includes heating a sulfonated polyester resin in an organic-free solvent, adding a solution of silver (I) ion to the heated resin in water to form a mixture, reducing silver (I) to silver (0) by heating the mixture from about 65° C. to about 90° C., thereby forming an emulsion of composite particles comprising a sulfonated polyester matrix and a plurality of silver nanoparticles disposed within the sulfonated polyester matrix, and allowing the silver nanoparticles to agglomerate into a silver nanodendrite structure. ## Claims ### Claim 1 A method comprising: heating a sulfonated polyester resin in an organic-free solvent; adding a solution of silver (I) ion to the heated resin in water to form a mixture; reducing silver (I) to silver(0) by heating the mixture from about 65° C. to about 90° C., thereby forming an emulsion of composite particles comprising a sulfonated polyester matrix and a plurality of silver nanoparticles disposed within the sulfonated polyester matrix; and allowing the silver nanoparticles to agglomerate into a silver nanodendrite structure. ### Claim 2 (depends on 1) The method of claim 1, wherein heating the sulfonated polyester resin is conducted at a temperature from about 65° C. to about 90° C. ### Claim 3 (depends on 1) The method of claim 1, wherein the organic-free solvent is de-ionized water. ### Claim 4 (depends on 1) The method of claim 1, wherein allowing the silver nanoparticles to agglomerate comprises leaving the emulsion to sit unstirred at ambient temperature for at least about one week. ### Claim 5 (depends on 1) The method of claim 1, wherein a source of silver (I) ion is selected from silver nitrate, silver sulfonate, silver fluoride, silver perchlorate, silver lactate, silver tetrafluoroborate, silver oxide and silver acetate. ### Claim 6 (depends on 1) The method of claim 1, wherein a concentration of silver ion after addition is a non-zero amount up to about 1 percent by weight of the solution or less. ### Claim 7 (depends on 1) The method of claim 1, wherein reducing silver (I) to silver(0) further comprises adding ascorbic acid or trisodium citrate as a reducing agent. ### Claim 8 (depends on 1) The method of claim 1, wherein the sulfonated polyester resin is a branched polymer. ### Claim 9 (depends on 1) The method of claim 1, wherein the sulfonated polyester matrix is a lithium, potassium, or sodium salt of a polymer selected from the group consisting of poly(1,2-propylene-5-sulfoisophthalate), poly(neopentylene-5-sulfoisophthalate), poly(diethylene-5-sulfoisophthalate), copoly-(1,2-propylene-5-sulfoisophthalate)-copoly-(1,2-propylene-terphthalate), copoly-(1,2-propylenediethylene-5-sulfoisophthalate)-copoly-(1,2-propylene-diethylene-terephthalatephthalate), copoly(ethylene-neopentylene-5-sulfoisophthalate)-copoly-(ethylene-neopentylene-terephthalatephthalate), and copoly(propoxylated bisphenol A)-copoly-(propoxylated bisphenol A-5-sulfoisophthalate). ### Claim 10 (depends on 1) The method of claim 1, wherein the sulfonated polyester resin comprises a polyol monomer unit selected from the group consisting of trimethylolpropane, 1,2-propanediol, diethylene glycol, and combinations thereof. ### Claim 11 (depends on 1) The method of claim 1, wherein the sulfonated polyester resin comprises a diacid monomer unit selected from the group consisting of terephthalic acid, sulfonated isophthalic acid, and combinations thereof. ### Claim 12 (depends on 1) The method of claim 1, wherein an amount of the sulfonated polyester resin is in a range from about 0.05 percent by weight of the mixture to about 50 percent by weight of the mixture. ### Claim 13 (depends on 1) The method of claim 1, wherein the method is conducted in the absence of a surfactant. ### Claim 14 A method comprising: heating a branched sulfonated polyester resin in de-ionized water; adding a solution of silver (I) ion to the heated resin in water to form a mixture, wherein silver (I) ion is present in a non-zero amount up to about 1 percent by weight of the mixture; reducing silver (I) to silver(0) by heating the mixture from about 65° C. to about 90° C., thereby forming an emulsion of composite particles comprising a sulfonated polyester matrix and a plurality of silver nanoparticles disposed within the sulfonated polyester matrix; and allowing the silver nanoparticles to agglomerate into a silver nanodendrite structure by leaving the emulsion to sit at ambient temperature for at least one week. ### Claim 15 (depends on 14) The method of claim 14, wherein the ratio of the concentration of silver (I) ion to branched sulfonated polyester resin is in a range from about 1:1 to about 1:120. ### Claim 16 (depends on 14) The methods of claim 14, wherein the silver nanodendrite forms after about three weeks. ### Claim 17 (depends on 14) The method of claim 14, wherein the method is carried out in the absence of a surfactant.