# US 12,222,168 B2 · Drawn polymer fibers for use in thermal applications > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,222,168 B2 - Document ID: US12222168B2 - Status: Granted - Kind: B2 - Application number: 17/375,182 - Filed: 2021-07-14 - Published: 2023-01-19 - Granted: 2025-02-11 - Earliest claimed: 2021-07-14 - Assignees: Massachusetts Institute of Technology - Applicants: Massachusetts Institute of Technology - Inventors: John G. Brisson; Kyle J. Thompson; John Cummings; Jacob Lazer Adams; Lauren Cantley - Web page: https://patentgrep.com/patent/US12222168B2 ## CPC - F28F 1/022: {with multiple channels} - B29C 55/22: of tubes {(B29C61/08 takes precedence)} - F28F 7/02: Blocks traversed by passages for heat-exchange media {(F28D7/0008 takes precedence)} - F28F 21/06: of plastics material - B29K 2069/00: Use of PC, i.e. polycarbonates {or derivatives thereof}, as moulding material - B29K 2079/085: {Thermoplastic polyimides, e.g. polyesterimides, PEI, i.e. polyetherimides, or polyamideimides; Derivatives thereof} - B29L 2031/18: Heat-exchangers or parts thereof - F28F 2255/06: composite, e.g. polymers with fillers or fibres - F28F 2260/02: having microchannels - F28F: DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION (water and air traps, air venting F16) - B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00) - B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS - B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES ## Abstract Drawn polymer fibers have internal channels running, at least partially, through the length of the fibers. These fibers may be configured to for use as thermal isolators that can thermally isolate material at the central core of the fiber from the outside environment. In such instances, the channels may be used as insulating channels and/or a heating or cooling fluid can be pumped through the channels to maintain the temperature of the material at the inner core. As another application, the fibers may be used as recuperative, regenerative, parallel-flow, counter-flow, cross-flow or condenser/evaporator heat exchangers. In this case, the channels may be used to direct fluid flow. The fiber may allow for the exchange of heat between fluids in the channels. ## Claims ### Claim 1 A heat exchanger comprising: a polymer fiber having a first end and a second end, the polymer fiber comprising: one or more fluid delivery channels disposed along a length of the polymer fiber between the first and second ends, the one or more fluid delivery channels configured to carry a fluid having a first temperature from the first end to the second end, wherein the polymer fiber is a single, polymer fiber having an outer wall and having a uniform cross-section along the entire length of the single polymer fiber from the first end of the single, polymer fiber to the second end of the single polymer fiber; and one or more fluid return channels disposed along the length of the polymer fiber with at least one or some of the fluid return channels extending between the first and second ends and configured to return a fluid from the second end of the polymer fiber, wherein the one or more fluid delivery channels have a first size and shape which define a first cross-sectional area and the one or more fluid return channels have a second size and shape which define a second cross-sectional area. ### Claim 2 (depends on 1) The heat exchanger of claim 1 wherein: each of the one or more fluid delivery channels and each of the one or more fluid return channels extend along the entire length of the polymer fiber from the first end of the polymer fiber to the second end of the polymer fiber; and an outer wall with a uniform cross-section along the length of the fiber. ### Claim 3 (depends on 1) The heat exchanger of claim 1 wherein the one or more fluid delivery channels and the one or more fluid return channels are provided having a generally rectangular cross-sectional shape. ### Claim 4 (depends on 1) The heat exchanger of claim 1 further comprising a static material disposed in at least one of the one or more fluid delivery channels to entirely fill the one or more fluid delivery channels wherein the static material corresponds to one or more of: a gas; a gel; a solid; and a composite material. ### Claim 5 (depends on 1) The heat exchanger of claim 1 further comprising a static material disposed in one or more fluid return channels wherein the static material fills the one or more fluid return channels and the static material corresponds to one or more of: a gas; a granular material; a gel; and a composite material. ### Claim 6 (depends on 1) The heat exchanger of claim 1 further comprising a material disposed in one or more of the one or more fluid delivery channels, wherein the material fills the one or more fluid delivery channels and the material corresponds to one or more of: a gas; a granular material; a gel; and a composite material. ### Claim 7 (depends on 1) The heat exchanger of claim 1 further comprising a material disposed in one or more of the one or more fluid return channels, wherein the material fills the one or more fluid return channels and the material corresponds to one or more of: a gas; a granular material; a gel; and a composite material. ### Claim 8 A heat exchanger comprising: a polymer fiber having a first end and a second end, the polymer fiber comprising: one or more fluid delivery channels disposed along a length of the polymer fiber between the first and second ends, the one or more fluid deliver channels configured to carry a fluid having a first temperature from the first end to the second end, wherein the polymer fiber is a single, polymer fiber having an outer wall and having a uniform cross-section and wherein the outer wall extends along the entire length of the single polymer fiber from the first end of the single polymer fiber to the second end of the single polymer fiber, and one or more fluid return channels disposed along the length of the polymer fiber with at least one or some of the fluid return channels extending between the first and second ends and configured to return a fluid from the second end of the polymer fiber. ### Claim 9 (depends on 8) The heat exchanger of claim 8 further comprising a material disposed in one or more of the one or more fluid return channels, wherein the material fills the one or more fluid return channels and the material corresponds to one or more of: a gas; a granular material; a gel; and a composite material. ### Claim 10 (depends on 8) The heat exchanger of claim 8 wherein: each of the one or more fluid delivery channels and each of the one or more fluid return channels extend along the entire length of the polymer fiber from the first end of the polymer fiber to the second end of the polymer fiber; and an outer wall with a uniform cross-section along the length of the fiber. ### Claim 11 (depends on 8) The heat exchanger of claim 8 wherein the one or more fluid delivery channels and the one or more fluid return channels are provided having a generally rectangular cross-sectional shape. ### Claim 12 (depends on 8) The heat exchanger of claim 8 further comprising a static material disposed in at least one of the one or more fluid delivery channels to entirely fill the one or more fluid delivery channels wherein the static material corresponds to one or more of: a gas; a gel; a solid; and a composite material. ### Claim 13 (depends on 8) The heat exchanger of claim 8 further comprising a static material disposed in one or more fluid return channels wherein the static material fills the one or more fluid return channels and the static material corresponds to one or more of: a gas; a granular material; a gel; and a composite material. ### Claim 14 A heat exchanger comprising: a polymer fiber having a first end and a second end, the polymer fiber comprising: one or more fluid delivery channels disposed along a length of the polymer fiber between the first and second ends, the one or more fluid delivery channels configured to carry a fluid having a first temperature from the first end to the second end, with the polymer fiber having an outer wall and having a uniform cross-section along the entire length of the polymer fiber from the first end of the polymer fiber to the second end of the polymer fiber; and one or more fluid return channels disposed along the length of the polymer fiber with at least one or some of the fluid return channels extending between the first and second ends and configured to return a fluid from the second end of the polymer fiber. ### Claim 15 (depends on 14) The heat exchanger of claim 14 wherein: each of the one or more fluid delivery channels and each of the one or more fluid return channels extend along the entire length of the polymer fiber from the first end of the polymer fiber to the second end of the polymer fiber; and an outer wall with a uniform cross-section along the length of the fiber. ### Claim 16 (depends on 14) The heat exchanger of claim 14 wherein the one or more fluid delivery channels and the one or more fluid return channels are provided having a generally rectangular cross-sectional shape. ### Claim 17 (depends on 14) The heat exchanger of claim 14 further comprising a static material disposed in at least one of the one or more fluid delivery channels to entirely fill the one or more fluid delivery channels wherein the static material corresponds to one or more of: a gas; a gel; a solid; and a composite material. ### Claim 18 (depends on 14) The heat exchanger of claim 14 further comprising a static material disposed in one or more fluid return channels wherein the static material fills the one or more fluid return channels and the static material corresponds to one or more of: a gas; a granular material; a gel; and a composite material. ### Claim 19 A heat exchanger comprising: a single polymer fiber having a first end, a second end, an outer wall and having a uniform cross-section along the entire length of the single polymer fiber from the first end of the single polymer fiber to the second end of the single polymer fiber, the single polymer fiber comprising: one or more fluid delivery channels disposed in the single polymer fiber, the one or more fluid delivery channels configured to carry a fluid having a first temperature; and one or more fluid return channels disposed in the single polymer fiber, the one or more fluid return channels configured to return a fluid from the second end of the single polymer fiber wherein the one or more fluid delivery channels and the one or more fluid return channels are either parallel or perpendicular to each other in the single polymer fiber. ### Claim 20 (depends on 19) The heat exchanger of claim 19 wherein the single polymer fiber comprises: a first wall comprising a polymer, the first polymer wall having an inner surface and an outer surface with the inner surface defining a first opening in the single polymer fiber, the first opening corresponding to one of: one of the one or more fluid delivery channels; or one of the one or more fluid return channels; a second wall comprising a polymer, the second polymer wall having an inner surface and an outer surface with the inner surface spaced apart from and substantially concentrically surrounding the outer surface of the first polymer wall; one or more supporting structures coupled between the first polymer wall and the second polymer wall, the one or more support structures having a size and shape selected to space the inner surface of the second polymer wall from the outer surface of the first polymer wall and to define one or more thermally insulating channels between the inner surface of the second polymer wall and the outer surface of the first polymer wall wherein at least one of the one or more thermally insulating channels are configured to thermally isolate at least a portion of the first opening in the single polymer fiber from an external environment. ### Claim 21 (depends on 20) The heat exchanger of claim 20 further comprising a third polymer wall concentrically surrounding the second polymer wall. ### Claim 22 (depends on 21) The heat exchanger of claim 21 further comprising one or more second supporting structures coupled between the second polymer wall and the third polymer wall, the one or more second support structures configured to space the third polymer wall from the second polymer wall to define one or more insulating channels between an inner surface of the third polymer wall and an outer surface of the second polymer wall. ### Claim 23 (depends on 20) The heat exchanger of claim 20 further comprising a thermally reflective material disposed on a surface of the first wall. ### Claim 24 (depends on 23) The heat exchanger of claim 23 wherein the thermally reflective material disposed on the surface of the first wall distal to the opening. ### Claim 25 (depends on 24) The heat exchanger of claim 24 wherein the thermally reflective material is disposed on the surface of the first wall proximal to the opening. ### Claim 26 (depends on 20) The heat exchanger of claim 20 wherein the first wall comprises one of: a cryogenic fiber, and a conductive wire. ### Claim 27 (depends on 20) The heat exchanger of claim 20 wherein the single polymer fiber is a drawn polymer fiber.