Isotropically Pored Patents (Class 210/500.22)
  • Patent number: 7144505
    Abstract: The present invention provides, inter alia, a composition useful for producing a homogeneous, semipermeable membrane, the composition comprising a polysulfone semipermeable membrane, the polysulfone semipermeable membrane comprising a mixture of: an ultra-high-molecular-weight hydrophilic polymer, a polysulfone compound and a solvent for the polysulfone compound, and the polysulfone semipermeable membrane having a homogeneous structure such that the polysulfone semipermeable membrane has a substantially uniform structure. Another aspect of this invention discloses methods for fabricating semipermeable membranes by homogeneously mixing the composition, melting the composition, and melt-spinning the molten composition. Another aspect of the present invention includes homogeneous, melt-spun, semipermeable membranes useful for liquid separation processes, such as, but not limited to, microfiltration, ultrafiltration, dialysis, and reverse osmosis.
    Type: Grant
    Filed: December 20, 2002
    Date of Patent: December 5, 2006
    Assignees: Baxter International Inc., Baxter Healthare S.A.
    Inventors: Wenli Han, Martin Ketterer, Jonnie Lee, Thanh Nguyen, George Washington, Delores Jordan, Dibyendu De
  • Patent number: 7077939
    Abstract: According to one embodiment an apparatus includes a membrane and at least a portion of a nanotube imbedded within the membrane. The portion of the nanotube imbedded within the membrane provides a conduit through the membrane.
    Type: Grant
    Filed: June 17, 2002
    Date of Patent: July 18, 2006
    Assignee: The Texas A&M University System
    Inventors: Richard M. Crooks, Li Sun
  • Patent number: 7048856
    Abstract: The present invention relates to ultrafiltration. In particular, the present invention provides a compact ultrafiltration device and methods for generating an ultrafiltrate, both of which can be used for a variety of applications, including, but not limited to filtering blood, diagnostic applications, and as a bioreactor.
    Type: Grant
    Filed: September 11, 2003
    Date of Patent: May 23, 2006
    Assignees: Regents of the University of Michigan, Cleveland Clinic Foundation
    Inventors: William H. Fissell, IV, H. David Humes, Shuvo Roy, Aaron Fleischman
  • Patent number: 6939468
    Abstract: The present invention relates to the field of synthetic polymeric microfiltration membrane materials that are fabricated to separate liquids from solids contained therein. One aspect of the invention relates to a highly asymmetric, hydrophilic microfiltration membrane with high surface porosity. The membrane is rendered hydrophilic through co-casting the sulfone polymer with a hydrophilic polymer, such as polyvinylpyrrolidone. The membranes of the invention are highly useful in testing devices for the quick detection of properties or components contained in liquid samples, such as diagnostic applications, as well as for other filtration applications that demand relatively large pore sizes, thick membranes, high asymmetry, and/or high lateral wicking speeds.
    Type: Grant
    Filed: April 29, 2003
    Date of Patent: September 6, 2005
    Assignee: Pall Corporation
    Inventors: I-Fan Wang, Richard A. Morris, Robert F. Zepf
  • Patent number: 6919026
    Abstract: A semipermeable membrane support includes, a non-woven fabric including main fiber and binder fiber, both of which are formed of synthetic resin fine fiber, the non-woven fabric being manufactured by heating and pressing after paper making, wherein the semipermeable membrane support has a ratio of a tensile strength in a paper feeding direction to that in a width direction of 2:1 to 1:1.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: July 19, 2005
    Assignees: Awa Paper Mfg. Co., Ltd., Nitto Denko Corporation
    Inventors: Yoshitsugu Hama, Yoshifumi Kusaka, Akihiro Okubo
  • Patent number: 6887408
    Abstract: Porous poly(aryl ether ketone) (PAEK) articles are prepared from PAEK/polyimide blends by selective chemical decomposition and subsequent removal of the polyimide phase. Porous PAEK articles exhibit highly interconnected pore structure and a narrow pore size distribution. The porous PAEK articles of the present invention can be utilized as a porous media for a broad range of applications, including membranes for fluid separations, such as microfiltration, ultrafiltration, nanofiltration, and as a sorption media.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: May 3, 2005
    Assignee: PoroGen LLC
    Inventor: Youxin Yuan
  • Patent number: 6884375
    Abstract: The present invention relates to filtration media having both hydrophobic (water-repellent) properties. The filtration media are produced using a fluorothermoplastic material, such as a terpolymer of tetrafluoroethylene, vinylidene fluoride, and hexafluoropropylene. The invention also relates to methods of preparing such filtration media using casting solution phase inversion.
    Type: Grant
    Filed: January 8, 2004
    Date of Patent: April 26, 2005
    Assignee: Pall Corporation
    Inventors: I-fan Wang, Richard McDonogh, James E. Rudolph, Jr.
  • Publication number: 20040256212
    Abstract: A water-soluble organic material condensation apparatus equipped with a distillation column for distilling an aqueous solution of a water-soluble organic material, wherein a vapor generated at the top of the distillation column or a condensed liquid from the vapor is introduced to a device other than the distillation column which has the function to separate water from the water-soluble organic material to thereby condense the water-soluble organic material through separating water and then the condensed water-soluble organic material is recycled to the distillation column. The device other than the distillation column is desirably a separative film such as a zeolite film. The apparatus is improved in the operation of the upper portion of the condensation section of the distillation column and allows energy savings during distillation.
    Type: Application
    Filed: April 16, 2004
    Publication date: December 23, 2004
    Inventors: Shiro Ikeda, Takashi Nakane
  • Patent number: 6811696
    Abstract: The present invention relates to filtration media having both hydrophobic (water-repellent) properties. The filtration media are produced using a fluorothermoplastic material, such as a terpolymer of tetrafluoroethylene, vinylidene fluoride, and hexafluoropropylene. The invention also relates to methods of preparing such filtration media using casting solution phase inversion.
    Type: Grant
    Filed: April 12, 2002
    Date of Patent: November 2, 2004
    Assignee: Pall Corporation
    Inventors: I-fan Wang, Richard McDonogh, James E. Rudolph, Jr.
  • Patent number: 6783008
    Abstract: A restraining system for hollow fibres is provided. The restraining system includes a plurality of longitudinally extending elements spaced from one another and supported by a number of discrete spacer elements, each spacer element extending generally transverse of said longitudinal elements, such that in combination with said longitudinal elements they define a cage-like structure.
    Type: Grant
    Filed: October 9, 2002
    Date of Patent: August 31, 2004
    Assignee: U.S. Filter Wastewater Group, Inc.
    Inventors: Fufang Zha, David John Cox
  • Patent number: 6719147
    Abstract: A novel supported mesoporous carbon ultrafiltration membrane and process for producing the same. The membranes comprise a mesoporous carbon layer that exists both within and external to the porous support. A liquid polymer precursor composition comprising both carbonizing and noncarbonizing templating polymers is deposited on the porous metal support. The coated support is then heated in an inert-gas atmosphere to pyrolyze the polymeric precursor and form a mesoporous carbon layer on and within the support. The pore-size of the membranes is dependent on the molecular weight of the noncarbonizing templating polymer precursor. The mesoporous carbon layer is stable and can withstand high temperatures and exposure to organic chemicals. Additionally, the porous metal support provides excellent strength properties. The composite structure of the membrane provides novel structural properties and allows for increased operating pressures allowing for greater membrane flow rates.
    Type: Grant
    Filed: April 27, 2001
    Date of Patent: April 13, 2004
    Assignee: The University of Delaware
    Inventors: Michael Strano, Henry C. Foley, Hans Agarwal
  • Patent number: 6692640
    Abstract: A mordenite (MOR) zeolite membrane is formed on a porous substrate and has crystals that are substantially oriented in a specific crystalline direction. A method for producing the mordenite (MOR) zeolite membrane includes the steps of: immersing a porous substrate in a gel of raw materials which contains zeolite constitution elements in molar ratios of 40-400 of SiO2/Al2O3, 10-120 of H2O/Na2O, and 10-40 of H2O/SiO2; and subjecting the gel in the presence of the porous substrate to hydrothermal synthesis at 150° C. or more to crystallize the MOR zeolite constitution elements and form a MOR zeolite membrane on the porous substrate.
    Type: Grant
    Filed: February 21, 2001
    Date of Patent: February 17, 2004
    Assignees: NGK Insulators, Ltd.
    Inventor: Masahiko Matsukata
  • Patent number: 6685810
    Abstract: A device for utilizing a non-gel self-assembled nano-feature array molecular sieve for analyzing molecules is provided. The molecular sieve device comprises an ordered array of self-assembled nano-features which function as a molecular sieve to separate molecules based on a suitable characteristic. A system for integrating the non-gel ordered self-assembled nano-feature array molecular sieve of this invention into a device for separating molecules based on a characteristic and a method for separating a wide range of molecules using the non-gel ordered self-assembled nano-feature array molecular sieve of the invention are also provided.
    Type: Grant
    Filed: February 22, 2001
    Date of Patent: February 3, 2004
    Assignees: California Institute of Technology, Brown University Research Foundation
    Inventors: Flavio Noca, Jingming Xu, Daniel S. Choi, Brian D. Hunt, Michael E. Hoenk, Robert S. Kowalczyk
  • Publication number: 20030196889
    Abstract: Cellulose nitrate membranes useful in immuno-assay diagnostic tests are rendered hydrophilic by exposure to a low energy plasma.
    Type: Application
    Filed: April 16, 2003
    Publication date: October 23, 2003
    Inventors: Karl Pflanz, Eric Jallerat, Hans Beer, Timo Klewitz
  • Publication number: 20030146145
    Abstract: The present invention provides improved synthetic polymer hydrogel permeation layers for use on active electronic matrix devices for biological assays. The permeation layers have a defined porous character, with mesopores in a size range between about 100 nanometers and about 1000 nanometers, and may also have micropores in the micrometer size range. The mesoporous synthetic hydrogel permeation layers demonstrate improved signal intensity and linearity characteristics as compared to nanoporous synthetic hydrogel permeation layers on active electronic matrix devices. In addition, the present invention also provides synthetic polymer hydrogel permeation layers which contain copolymerized attachment sites for nucleic acid probes or other biomolecules.
    Type: Application
    Filed: December 10, 2001
    Publication date: August 7, 2003
    Inventors: Jainamma Krotz, Daniel D. Smolko, Howard R. Reese, Thomas J. Onofrey, Daguang Wang, Theodore M. Winger, John R. Havens
  • Publication number: 20030089659
    Abstract: A restraining system for hollow fibres is provided. The restraining system includes a plurality of longitudinally extending elements spaced from one another and supported by a number of discrete spacer elements, each spacer element extending generally transverse of said longitudinal elements, such that in combination with said longitudinal elements they define a cage-like structure.
    Type: Application
    Filed: October 9, 2002
    Publication date: May 15, 2003
    Inventors: Fufang Zha, David John Cox
  • Publication number: 20030080042
    Abstract: An adjustable nanopore is fabricated by placing the surfaces of two planar substrates in contact, wherein each substrate contains a hole having sharp corners and edges. A corner is brought into proximity with an edge to define a triangular aperture of variable area. Ionic current in a liquid solution and through the aperture is monitored as the area of the aperture is adjusted by moving one planar substrate with respect to the other along two directional axes and a rotational axis. Piezoelectric positioners can provide subnanometer repeatability in the adjustment process. The invention is useful for characterizing, cleaving, and capturing molecules, molecular complexes, and supramolecular complexes which pass through the nanopore, and provides an improvement over previous devices in which the hole size of nanopores fabricated by etching and/or redeposition is fixed after fabrication.
    Type: Application
    Filed: October 30, 2001
    Publication date: May 1, 2003
    Inventors: Philip W. Barth, Daniel B. Roitman, Joel Myerson
  • Publication number: 20030080060
    Abstract: A micromachined filter system comprises a micromachined filter integrated in a micro-device. In various embodiments, the micromachined filter system is fabricated along with the micro-device using the same or similar techniques. The micromachined filter may comprise a polysilicon filter. According to the micromachined filter system, the micromachined filter may be formed in one or more polysilicon layers of the micro-device. The micromachined filter may also comprise a polyimide filter. In various embodiments, the micromachined filter may be situated downstream of a fluid inlet of the micro-device. In various embodiments, a non-integrated, external pre-filter may be used in conjunction with an integrated micromachined filter.
    Type: Application
    Filed: October 30, 2001
    Publication date: May 1, 2003
    Inventor: Peter M .Gulvin
  • Patent number: 6527955
    Abstract: A novel microporous membrane comprising a hot-melt adhesive and an engineering plastics, the methods of preparing such microporous membrane and the uses of the microporous membrane in, e.g., batteries, super capacitors, fuel cells, sensors, electrochromic devices or the like.
    Type: Grant
    Filed: December 28, 2001
    Date of Patent: March 4, 2003
    Assignee: Policell Technologies, Inc.
    Inventor: Luying Sun
  • Patent number: 6497821
    Abstract: A method and apparatus for filtering suspensions of medical and biological fluids, one aspect of which is separating a suspension comprising at least two types of particles which are differently sized or shaped and in which the first type of particle may be deformable at a relatively lower force and/or faster rate than the second type of particle. A filter member is provided having substantially precisely dimensioned pore sizes, with the pores being dimensioned to allow passage of the first type of suspended particle without distortion or only minimal distortion and passage of the second type of particle only with substantial distortion.
    Type: Grant
    Filed: May 17, 1999
    Date of Patent: December 24, 2002
    Assignee: Baxter International Inc.
    Inventors: David Bellamy, Jr., Paul R. Prince, Michael O. Pekkarinen, Shmuel Sternberg
  • Patent number: 6440306
    Abstract: Highly asymmetric polymeric membranes with large pores which yield bubble points in the range of 0.5 to 25 psid and superior flow characteristics. The membranes can be cast from both metastable dispersions and from homogenous casting formulations. The technique of synthesis involves exposure of the cast membrane to humid air to create large surface pores on the exposed side.
    Type: Grant
    Filed: January 25, 2000
    Date of Patent: August 27, 2002
    Assignee: Pall Corporation
    Inventors: Jerome Ditter, Richard A. Morris, Robert Zepf
  • Publication number: 20020088748
    Abstract: A pore plugging material, for pH dependent membrane diffusion, in which cyclic olefins having phosphazene-functional moieties provide predictable erosion properties when used to plug pores is separation barriers and other porous membranes. Specific properties of the polymers are dependent on several factors, including molecular weight and identity of side groups attached to the phosphazene moiety. However, as a class, phosphazene-functional cyclic olefins provide both predictable erodibility and uniformly benign hydrolysis products and are, therefore, uniquely suitable as pore plugging polymers for separation barriers and membranes of all kinds. The invention, therefore, embraces the provision of a pH-sensitive erodible pore plugging material to pores in separation barriers and membranes of all kinds.
    Type: Application
    Filed: November 1, 2001
    Publication date: July 11, 2002
    Inventors: Harry R. Allcock, Jared Bender, Roy H. Hammerstedt, Stephen Schwartz, Walter Laredo
  • Publication number: 20020033367
    Abstract: A method and apparatus for filtering suspensions of medical and biological fluids, one aspect of which is separating a suspension comprising at least two types of particles which are differently sized or shaped and in which the first type of particle may be deformable at a relatively lower force and/or faster rate than the second type of particle. A filter member is provided having substantially precisely dimensioned pore sizes, with the pores being dimensioned to allow passage of the first type of suspended particle without distortion or only minimal distortion and passage of the second type of particle only with substantial distortion.
    Type: Application
    Filed: September 18, 2001
    Publication date: March 21, 2002
    Applicant: Baxter International Inc.
    Inventors: Paul R. Prince, Michael O. Pekkarinen, David Bellamy, Shmuel Sternberg
  • Patent number: 6277281
    Abstract: Highly asymmetric polymeric membranes with large pores which yield bubble points in the range of 0.5 to 25 psid and superior flow characteristics. The membranes can be cast from both metastable dispersions and from homogenous casting formulations. The technique of synthesis involves exposure of the cast membrane to humid air to create large surface pores on the exposed side.
    Type: Grant
    Filed: May 15, 2000
    Date of Patent: August 21, 2001
    Assignee: USF Filtration and Separations Group Inc.
    Inventors: Jerome Ditter, Richard A. Morris, Robert Zepf