Patents by Inventor Krishna Nadella

Krishna Nadella has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20230083603
    Abstract: A material for making an underlayment of a floor includes a thermoplastic polymer that has a thickness and a microstructure. The microstructure includes a plurality of closed cells, each cell containing a void and each cell having a maximum dimension extending across the void within the cell that is less than or equal to 200 micrometers long. The microstructure also includes a density that is greater than or equal to 0.18 grams per cubic centimeter.
    Type: Application
    Filed: September 9, 2022
    Publication date: March 16, 2023
    Inventors: Vipin Kumar, Krishna Nadella
  • Patent number: 10029401
    Abstract: The invention disclosed herein relates to relates to foamed thermoplastic material objects and articles of manufacture having an internal layered cellular structure, as well as to methods of making the same. In one embodiment, the invention is directed to a multi-layer foamed polymeric article of manufacture, comprising: a non-laminated multi-layer thermoplastic material sheet, wherein the multi-layer thermoplastic material sheet has first and second discrete outer layers sandwiching a plurality of discrete inner foamed layers, and wherein the two outer layers and plurality discrete inner foamed layers are integral with one another. The thermoplastic material may be a semi-crystalline polymer such as, for example, PET (polyethylene terephthalate), PEEK (polyetheretherketone), PEN (polyethylene naphthalate), PBT (polybutylene terephthalate), PMMA (polymethyl methacrylate), PLA (polylactide), polyhydroxy acid (PHA), thermoplastic urethane (TPU), or blends thereof.
    Type: Grant
    Filed: September 14, 2012
    Date of Patent: July 24, 2018
    Assignees: Dart Container Corporation, The University of Washington
    Inventors: Krishna Nadella, Gregory Branch, Vipin Kumar, Michael Waggoner
  • Patent number: 9914247
    Abstract: A method for infusing gas into a thermoplastic material includes positioning a sheet of a thermoplastic material into a vertical or substantially vertical position; positioning a sheet of a gas-permeable material into a vertical or substantially vertical position; and winding together the positioned sheet of thermoplastic material sheet and the positioned sheet of gas-permeable material to form a roll of the thermoplastic material interleaved with the gas-permeable material, the interleaved roll having a longitudinal axis oriented in a vertical or substantially vertical position. The method also includes exposing the interleaved roll to an atmosphere of a gas pressurized to infuse the thermoplastic material with the gas, while the longitudinal axis of the interleaved roll is oriented in a vertical or substantially vertical position; and then unwinding the gas-infused interleaved roll, while the longitudinal axis of the interleaved roll remains in a vertical or substantially vertical position.
    Type: Grant
    Filed: February 28, 2013
    Date of Patent: March 13, 2018
    Assignee: Dart Container Corporation
    Inventor: Krishna Nadella
  • Patent number: 9884440
    Abstract: Disclosed herein are roll fed air heated flotation ovens and related thermoforming systems, assemblies, and machines that enable the corrugation-free expansion of a gas impregnated thermoplastic web passing through an oven chamber (without use of a pin-chain assembly), as well as to related methods. In an embodiment, a gas impregnated thermoplastic web is conveyed and expanded through an elongated air heated oven chamber, wherein the elongated oven chamber includes a plurality of downwardly directed heated air nozzles positioned at regular intervals along and within the upper portion of the oven chamber, and a plurality of upwardly directed heated air nozzles positioned at regular intervals along and within the lower portion of the oven chamber, but staggered apart from the downwardly directed heated air nozzles such that the gas impregnated thermoplastic material web undulates in an up and down wavelike fashion, thereby minimizing sagging, bagging, puckering, and/or buckling of the web.
    Type: Grant
    Filed: August 22, 2016
    Date of Patent: February 6, 2018
    Assignee: Dart Container Corporation
    Inventors: Gregory Branch, Krishna Nadella
  • Publication number: 20160354955
    Abstract: Disclosed herein are roll fed air heated flotation ovens and related thermoforming systems, assemblies, and machines that enable the corrugation-free expansion of a gas impregnated thermoplastic web passing through an oven chamber (without use of a pin-chain assembly), as well as to related methods. In an embodiment, a gas impregnated thermoplastic web is conveyed and expanded through an elongated air heated oven chamber, wherein the elongated oven chamber includes a plurality of downwardly directed heated air nozzles positioned at regular intervals along and within the upper portion of the oven chamber, and a plurality of upwardly directed heated air nozzles positioned at regular intervals along and within the lower portion of the oven chamber, but staggered apart from the downwardly directed heated air nozzles such that the gas impregnated thermoplastic material web undulates in an up and down wavelike fashion, thereby minimizing sagging, bagging, puckering, and/or buckling of the web.
    Type: Application
    Filed: August 22, 2016
    Publication date: December 8, 2016
    Inventors: GREGORY BRANCH, KRISHNA NADELLA
  • Patent number: 9427903
    Abstract: Disclosed herein are roll fed air heated flotation ovens and related thermoforming systems, assemblies, and machines that enable the corrugation-free expansion of a gas impregnated thermoplastic web passing through an oven chamber (without use of a pin-chain assembly), as well as to related methods. In an embodiment, a gas impregnated thermoplastic web is conveyed and expanded through an elongated air heated oven chamber, wherein the elongated oven chamber includes a plurality of downwardly directed heated air nozzles positioned at regular intervals along and within the upper portion of the oven chamber, and a plurality of upwardly directed heated air nozzles positioned at regular intervals along and within the lower portion of the oven chamber, but staggered apart from the downwardly directed heated air nozzles such that the gas impregnated thermoplastic material web undulates in an up and down wavelike fashion, thereby minimizing sagging, bagging, puckering, and/or buckling of the web.
    Type: Grant
    Filed: July 9, 2012
    Date of Patent: August 30, 2016
    Assignee: Dart Container Corporation
    Inventors: Gregory Branch, Krishna Nadella
  • Publication number: 20160176079
    Abstract: An apparatus and method are provided herein for solid-state microcellular processing, wherein a gas-saturated solid thermoplastic web is fed into an enclosed processing system comprising a plurality of thermal rollers and nip rollers that work together to constrain the thermoplastic web while expanding it through a series of thermal rollers and nip pressure. By constraining the web and controlling its rate of expansion, the present invention is intended to produce microcellular thermoplastic webs with a uniform thickness and flat surface.
    Type: Application
    Filed: December 17, 2015
    Publication date: June 23, 2016
    Inventors: KRISHNA NADELLA, STEVE WOOLDRIDGE
  • Patent number: 9296185
    Abstract: A method for joining two components includes positioning a thermoplastic polymer portion of a first component adjacent a thermoplastic polymer portion of a second component such that the first and second portions form an interface. At least one of the portions includes a microstructure having a plurality of closed cells, each cell containing a void and each cell having a maximum dimension extending across the void. The method also includes exerting pressure on the thermoplastic polymer portions to form a bond at the interface that holds the portions together. The plurality of closed cells, and especially those adjacent the surface of the thermoplastic polymer portion that form the interface, help isolate thermally and/or chemically the surface from the remainder of the portion.
    Type: Grant
    Filed: April 19, 2011
    Date of Patent: March 29, 2016
    Assignees: Dart Container Corporation, University of Washington
    Inventors: Krishna Nadella, Xiaoxi Wang, Vipin Kumar
  • Patent number: 9203070
    Abstract: A method for making a flat polymer foam having a core layer of nano-sized open, interconnected cells that includes saturating a solid-state polymer with a supercritical fluid, allowing the gas to desorb for at least 35 minutes, and then heating the gas-saturated solid polymer for at least 3 minutes while constraining the foam in the thickness dimension. Any skin layer formed on the exterior may be removed via polishing, thus creating a foam with an open structure from side to side. The foam can be used as a battery separator.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: December 1, 2015
    Assignee: University of Washington through its Center for Commercialization
    Inventors: Vipin Kumar, Brian Aher, Krishna Nadella, Michael Waggoner
  • Publication number: 20150042005
    Abstract: A method for infusing gas into a thermoplastic material includes positioning a sheet of a thermoplastic material into a vertical or substantially vertical position; positioning a sheet of a gas-permeable material into a vertical or substantially vertical position; and winding together the positioned sheet of thermoplastic material sheet and the positioned sheet of gas-permeable material to form a roll of the thermoplastic material interleaved with the gas-permeable material, the interleaved roll having a longitudinal axis oriented in a vertical or substantially vertical position. The method also includes exposing the interleaved roll to an atmosphere of a gas pressurized to infuse the thermoplastic material with the gas, while the longitudinal axis of the interleaved roll is oriented in a vertical or substantially vertical position; and then unwinding the gas-infused interleaved roll, while the longitudinal axis of the interleaved roll remains in a vertical or substantially vertical position.
    Type: Application
    Filed: February 28, 2013
    Publication date: February 12, 2015
    Inventor: Krishna Nadella
  • Publication number: 20150037542
    Abstract: A composite material includes a core and a shell that covers the core. The core has a volume that includes a first material and a void wherein the first material occupies less than 50% of the core's volume and has a three-dimensional shape that includes a plurality of components each having the same shape and arranged to form a series of repeating components within the volume. The shell includes a second material joined to the first material. Each of the first and second materials includes a thickness having a middle region and a outer region, and at least one of the first and second materials, includes a microstructure.
    Type: Application
    Filed: March 29, 2013
    Publication date: February 5, 2015
    Inventors: Krishna Nadella, Michael Waggoner
  • Publication number: 20140349069
    Abstract: A thermoplastic material having a thickness includes a polymer having a microstructure that includes a plurality of closed cells disposed in an inner region of the material's thickness. Each of the plurality of closed cells contains a void and each of the cells has a maximum dimension extending across the void within the cell that ranges between 1 micrometer and 500 micrometers long. The thermoplastic material also includes a substantially solid skin disposed in an outer region of the material's thickness. The skin includes a surface having a surface energy and a texture that increases the surface energy to more than 38 dynes per square centimeter.
    Type: Application
    Filed: January 14, 2013
    Publication date: November 27, 2014
    Inventors: Krishna Nadella, Shawna Laramore
  • Patent number: 8877331
    Abstract: The invention relates to foamed thermoplastic material articles of manufacture having an internal layered cellular structure (with segmented and varying physical properties across one or more dimensions). In one embodiment, the invention is directed to a multi-layer foamed polymeric article of manufacture having a plurality of discrete physical properties segmented across one or more dimensions, comprising: a non-laminated multi-layer polymeric object having at least one discrete outer layer positioned adjacent to a plurality of discrete inner foamed layers, wherein the at least one discrete outer layer and the plurality of discrete inner foamed layers are integral with one another, and wherein the at least one discrete outer layer has an outer layer physical property and each of the plurality of discrete inner foamed layers has a respective inner foamed layer physical property, wherein the outer layer physical property and the inner foamed layer physical property are different from each other.
    Type: Grant
    Filed: September 24, 2009
    Date of Patent: November 4, 2014
    Assignees: MicroGREEN Polymers, University of Washington
    Inventors: Krishna Nadella, Xiaoxi Wang
  • Publication number: 20140287321
    Abstract: A method for making a flat polymer foam having a core layer of nano-sized open, interconnected cells that includes saturating a solid-state polymer with a supercritical fluid, allowing the gas to desorb for at least 35 minutes, and then heating the gas-saturated solid polymer for at least 3 minutes while constraining the foam in the thickness dimension. Any skin layer formed on the exterior may be removed via polishing, thus creating a foam with an open structure from side to side. The foam can be used as a battery separator.
    Type: Application
    Filed: March 14, 2014
    Publication date: September 25, 2014
    Applicant: University of Washington through its Center for Commercialization
    Inventors: Vipin Kumar, Brian Aher, Krishna Nadella, Michael Waggoner
  • Publication number: 20130065981
    Abstract: The invention disclosed herein relates to relates to foamed thermoplastic material objects and articles of manufacture having an internal layered cellular structure, as well as to methods of making the same. In one embodiment, the invention is directed to a multi-layer foamed polymeric article of manufacture, comprising: a non-laminated multi-layer thermoplastic material sheet, wherein the multi-layer thermoplastic material sheet has first and second discrete outer layers sandwiching a plurality of discrete inner foamed layers, and wherein the two outer layers and plurality discrete inner foamed layers are integral with one another. The thermoplastic material may be a semi-crystalline polymer such as, for example, PET (polyethylene terephthalate), PEEK (polyetheretherketone), PEN (polyethylene napthalate), PBT (polybutylene terephthalate), PMMA (polymethyl methacrylate), PLA (polyactide), polyhydroxy acid (PHA), thermoplastic urethane (TPU), or blends thereof.
    Type: Application
    Filed: September 14, 2012
    Publication date: March 14, 2013
    Inventors: Krishna Nadella, Gregory Branch, Vipin Kumar, Michael A. Waggoner
  • Patent number: 8377548
    Abstract: The invention disclosed herein relates to relates to foamed thermoplastic material objects and articles of manufacture having an internal layered cellular structure, as well as to methods of making the same. In one embodiment, the invention is directed to a multi-layer foamed polymeric article of manufacture, comprising: a non-laminated multi-layer thermoplastic material sheet, wherein the multi-layer thermoplastic material sheet has first and second discrete outer layers sandwiching a plurality of discrete inner foamed layers, and wherein the two outer layers and plurality discrete inner foamed layers are integral with one another. The thermoplastic material may be a semi-crystalline polymer such as, for example, PET (polyethylene terephthalate), PEEK (polyetheretherketone), PEN (polyethylene napthalate), PBT (polybutylene terephthalate), PMMA (polymethyl methacrylate), PLA (polyactide), polyhydroxy acid (PHA), thermoplastic urethane (TPU), or blends thereof.
    Type: Grant
    Filed: October 5, 2010
    Date of Patent: February 19, 2013
    Assignees: MicroGREEN Polymers Inc., University of Washington
    Inventors: Krishna Nadella, Gregory Branch, Vipin Kumar, Michael A. Waggoner
  • Publication number: 20130032289
    Abstract: A method for joining two components includes positioning a thermoplastic polymer portion of a first component adjacent a thermoplastic polymer portion of a second component such that the first and second portions form an interface. At least one of the portions includes a microstructure having a plurality of closed cells, each cell containing a void and each cell having a maximum dimension extending across the void. The method also includes exerting pressure on the thermoplastic polymer portions to form a bond at the interface that holds the portions together. The plurality of closed cells, and especially those adjacent the surface of the thermoplastic polymer portion that form the interface, help isolate thermally and/or chemically the surface from the remainder of the portion.
    Type: Application
    Filed: April 19, 2011
    Publication date: February 7, 2013
    Applicants: MicroGREEN Polymers, Inc., University of Washington
    Inventors: Krishna Nadella, Xiaoxi Wang, Vipin Kumar
  • Publication number: 20120183710
    Abstract: A process for producing cellular thermoplastic articles. The process comprises the steps of treating a solid parison made from a thermoplastic material with a saturating gas at an elevated pressure for a period of time to provide a gas-saturated parison; heating the gas-saturated parison to prepare a cellular parison; placing the cellular parison in a mold; and blowing a molding gas into the cellular parison to expand the cellular parison into the shape of the mold to provide a shaped cellular article.
    Type: Application
    Filed: March 26, 2012
    Publication date: July 19, 2012
    Applicant: University of Washington through its Center for Commercialization
    Inventors: Vipin Kumar, Krishna Nadella, Michael Waggoner
  • Patent number: 8168114
    Abstract: A process for producing cellular thermoplastic articles. The process comprises the steps of treating a solid parison made from a thermoplastic material with a saturating gas at an elevated pressure for a period of time to provide a gas-saturated parison; heating the gas-saturated parison to prepare a cellular parison; placing the cellular parison in a mold; and blowing a molding gas into the cellular parison to expand the cellular parison into the shape of the mold to provide a shaped cellular article.
    Type: Grant
    Filed: September 12, 2008
    Date of Patent: May 1, 2012
    Assignee: University of Washington through its Center for Commercialization
    Inventors: Vipin Kumar, Krishna Nadella, Michael Waggoner
  • Publication number: 20120065287
    Abstract: Disclosed herein are methods and pressure vessels for solid-state microcellular processing of thermoplastic rolls and sheets. In one embodiment, the present invention is directed to a method for making a gas impregnated interleaved roll, which method comprises: providing a pressure vessel having an internal pressure chamber and a rotatable shaft horizontally positioned within the pressure chamber; placing an interleaved roll about the rotatable shaft and within the pressure chamber, wherein the interleaved roll is made from a thermoplastic material sheet interleaved together with a gas-channeling material sheet; pressurizing the pressure chamber to a selected pressure; rotating the rotatable shaft having the interleaved roll thereabouts (thereby rotating the interleaved roll) while under pressure for a selected period of time; and depressurizing the internal chamber to yield the gas impregnated interleaved roll.
    Type: Application
    Filed: November 18, 2011
    Publication date: March 15, 2012
    Inventors: Krishna Nadella, Steven Powers, Thomas G. Malone