# US 8,465,883 B2 · Nanostructured polymer membranes for proton conduction > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,465,883 B2 - Document ID: US8465883B2 - Status: Granted - Kind: B2 - Application number: 12/667,219 - Filed: 2008-06-30 - Published: 2011-03-03 - Granted: 2013-06-18 - Earliest claimed: 2007-07-11 - Assignees: The Regents of the University of California - Applicants: Nitash Pervez Balsara; Moon Jeong Park - Inventors: Nitash Pervez Balsara; Moon Jeong Park - Web page: https://patentgrep.com/patent/US8465883B2 ## CPC - C08J 5/2243: {obtained by introduction of active groups capable of ion-exchange into compounds of the type C08J5/2231} - B01D 69/02: characterised by their properties - B01D 71/261: {Polyethylene} - B01D 71/262: {Polypropylene} - B01D 71/80: Block polymers - B01J 47/12: characterised by the use of ion-exchange material in the form of ribbons, filaments, fibres or sheets, e.g. membranes (electrodialysis or electro-osmosis B01D61/42) - C08F 8/04: Reduction, e.g. hydrogenation - C08F 8/36: Sulfonation; Sulfation - C08F 297/04: polymerising vinyl aromatic monomers and conjugated dienes - C08F 297/046: {polymerising vinyl aromatic monomers and isoprene, optionally with other conjugated dienes} - C08J 3/24: Crosslinking, e.g. vulcanising, of macromolecules (mechanical aspects B29C35/00; crosslinking agents C08K) - H01B 1/122: {Ionic conductors} - H01M 8/1023: having only carbon, e.g. polyarylenes, polystyrenes or polybutadiene-styrenes - H01M 8/1065: characterised by the form, e.g. perforated or wave-shaped - H01M 8/1067: characterised by their physical properties, e.g. porosity, ionic conductivity or thickness - B01D 2325/0212: Symmetric or isoporous membranes - B01D 2325/14: Membrane materials having negatively charged functional groups - B01D 2325/36: Hydrophilic membranes - B01D 2325/38: Hydrophobic membranes - C08F 2800/20: as weight or mass percentages - C08J 2353/02: of vinyl aromatic monomers and conjugated dienes - H01M 2300/0082: Organic polymers - Y02E 60/50: Fuel cells - 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) - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K}) - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Polymers having an improved ability to entrain water are characterized, in some embodiments, by unusual humidity-induced phase transitions. The described polymers (e.g., hydrophilically functionalized block copolymers) have a disordered state and one or more ordered states (e.g., a lamellar state, a gyroid state, etc.). In one aspect, the polymers are capable of undergoing a disorder-to-order transition while the polymer is exposed to an increasing temperature at a constant relative humidity. In some aspects the polymer includes a plurality of portions, wherein a first portion forms proton-conductive channels within the membrane and wherein the channels have a width of less than about 6 nm. The described polymers are capable of entraining and preserving water at high temperature and low humidity. Surprisingly, in some embodiments, the polymers are capable of entraining greater amounts of water with the increase of temperature. The polymers can be used in Polymer Electrolyte Membranes in fuel cells. ## Claims ### Claim 1 A polymer electrolyte membrane (PEM) comprising a portion forming proton-conductive channels within the membrane, wherein the channels have a width of less than about 6 nm. ### Claim 2 (depends on 1) The membrane of claim 1, wherein the portion comprises a hydrophilically functionalized polymer. ### Claim 3 (depends on 2) The membrane of claim 2, wherein the hydrophilically functionalized polymer is a sulphonated polymer. ### Claim 4 (depends on 1) The membrane of claim 1, wherein the width of the channels is less than about 5 nm. ### Claim 5 (depends on 4) The membrane of claim 4, wherein the width of the channels is less than about 3 nm. ### Claim 6 (depends on 1) The membrane of claim 1 further comprising a block copolymer, wherein the copolymer comprises hydrophilic and hydrophobic blocks. ### Claim 7 (depends on 6) The membrane of claim 6, wherein the block copolymer forms an ordered nanostructure. ### Claim 8 (depends on 7) The membrane of claim 7, wherein the block copolymer forms an ordered nanostructure in a hydrated state. ### Claim 9 (depends on 7) The membrane of claim 7, wherein the ordered nanostructure is a lamellar structure or a gyroid structure. ### Claim 10 (depends on 6) The membrane of claim 6, wherein the block copolymer has a molecular weight of less than about 9,000 g/mol. ### Claim 11 (depends on 6) The membrane of claim 6, wherein the hydrophilic block comprises sulfonate groups. ### Claim 12 (depends on 6) The membrane of claim 6, wherein the block copolymer comprises polystyrenesulfonate-block-polymethylbutylene (PSS-b-PMB). ### Claim 13 (depends on 12) The membrane of claim 12, wherein the PSS-b-PMB has a molecular weight of less than about 8,000 g/mol. ### Claim 14 (depends on 6) The membrane of claim 6, wherein the hydrophilic block comprises aryl groups and wherein less than about 60% of the aryl groups are sulphonated. ### Claim 15 (depends on 1) The membrane of claim 1, wherein the membrane has a proton conductivity of at least about 0.15 S/cm at a temperature of greater than about 60 degrees C. ### Claim 16 (depends on 1) The membrane of claim 1, wherein the membrane retains a greater amount of water at a higher temperature than it retains at a lower temperature.