Patents by Inventor Warren H. Griffin

Warren H. Griffin 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).

  • Patent number: 8785510
    Abstract: Prepare a closed-cell alkenyl aromatic polymer foam by an extrusion process using a blowing agent composition that contains at least 30 weight-percent of the chlorine-free hydrofluorocarbon blowing agent such that the foam has a density of 48 kilograms per cubic meter or less, contains more than 50 weight-percent styrene-acrylonitrile copolymer based on total polymer weight and at least eight weight-percent of a chlorine-free hydrofluorocarbon blowing agent that has a lower solubility in polystyrene than 1,1,2,2-tetrafluoroethane (HFC-134).
    Type: Grant
    Filed: March 13, 2008
    Date of Patent: July 22, 2014
    Assignee: Dow Global Technologies LLC
    Inventors: Van-Chau Vo, Richard T. Fox, Warren H. Griffin, John Gordon-Duffy, Lawrence S. Hood, Roy E. Smith
  • Patent number: 8198340
    Abstract: Alkenyl aromatic polymer foam comprising a polymer matrix containing one or more polymer and defining a plurality of cells having an average cell size wherein: (a) the alkenyl aromatic polymer foam has: —(i) an average cell size that is in a range of 0.02 and 5 millimeters; —(ii) a density of 64 kilograms per cubic meter or less; —(iii) an open cell content less than 30 percent; and —(iv) a cell size variation of 30% or less; and wherein the foam further comprises one or more fluorinated alkene blowing agent at a concentration of 0.03 moles or more and 0.3 moles or less per 100 grams of polymer foam.
    Type: Grant
    Filed: March 10, 2008
    Date of Patent: June 12, 2012
    Assignee: Dow Global Technologies LLC
    Inventors: Van-Chau Vo, Richard T. Fox, Warren H. Griffin
  • Patent number: 7931963
    Abstract: An improved energy absorbing member comprising, an thermoplastic cellular polymer in contact with a structural element such as a metal guard rail or automotive door, wherein the cellular polymer has an average cell size of at least about 0.75 mm and at least one of CE/CT, CV/CT and CH/CT is about 0.25 to about 0.4 said one of CE/CT, CV/CT and CH/CT having a compressive efficiency of at least 70% at a 60% strain, CE, CV and CH being the compressive strength of the cellular polymer in each of three orthogonal directions E, V and H where one of these directions is the direction of maximum compressive strength in the foam and CT equals the sum of CE, CV and CH.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: April 26, 2011
    Assignee: Dow Global Technologies LLC
    Inventors: Myron J. Maurer, Gavin D. Vogel, Byoung-Ho Choi, Warren H. Griffin, Kalyan Sehanobish
  • Publication number: 20100292355
    Abstract: Prepare an alkenyl-aromatic foam having good surface quality, high thermal insulating properties and low density using an extrusion method by expanding a foamable polymer composition of an alkenyl-aromatic polymer composition containing less than 20 weight-percent covalently bonded halogens and having a polydispersity of less than 2.5 and a water solubility greater than 0.09 moles per kilogram and 2.2 moles per kilogram or less at 130 degrees Celsius and 101 kilopascals pressure and 0.8-2 moles per kilogram of a blowing agent containing 0.4 moles per kilogram or more of a chlorine-free fluorinated blowing agents and water at a concentration of at least 0.22 moles per kilogram; wherein moles per kilogram are relative to kilograms of alkenyl-aromatic polymer. The resulting foam has a density of 64 kilograms per cubic meter or less and a thermal conductivity of 32 milliwatts per meter-Kelvin or less after 180 days.
    Type: Application
    Filed: April 18, 2008
    Publication date: November 18, 2010
    Inventors: Mark A. Barger, Charles A. Berglund, Clive P. Bosnyak, Stephanie A. Donati, John Gordon-Duffy, Warren H. Griffin, Ing-Feng Hu, Jean-Francois Koenig, Simon Lee, Creston D. Shmidt, Roy E. Smith, Chau V. Vo
  • Publication number: 20100099783
    Abstract: Prepare a closed-cell alkenyl aromatic polymer foam by an extrusion process using a blowing agent composition that contains at least 30 weight-percent of the chlorine-free hydrofluorocarbon blowing agent such that the foam has a density of 48 kilograms per cubic meter or less, contains more than 50 weight-percent styrene-acrylonitrile copolymer based on total polymer weight and at least eight weight-percent of a chlorine-free hydrofluorocarbon blowing agent that has a lower solubility in polystyrene than 1,1,2,2-tetrafluoroethane (HFC-134).
    Type: Application
    Filed: March 13, 2008
    Publication date: April 22, 2010
    Inventors: Van-Chau Vo, Richard T. Fox, Warren H. Griffin, John Gordon-Duffy, Lawrence S. Hood, Roy E. Smith
  • Publication number: 20100087555
    Abstract: Alkenyl aromatic polymer foam comprising a polymer matrix containing one or more polymer and defining a plurality of cells having an average cell size wherein: (a) the alkenyl aromatic polymer foam has: —(i) an average cell size that is in a range of 0.02 and 5 millimeters; —(ii) a density of 64 kilograms per cubic meter or less; —(iii) an open cell content less than 30 percent; and—(iv) a cell size variation of 30% or less; and wherein the foam further comprises one or more fluorinated alkene blowing agent at a concentration of 0.03 moles or more and 0.3 moles or less per 100 grams of polymer foam.
    Type: Application
    Filed: March 10, 2008
    Publication date: April 8, 2010
    Inventors: Van-chau Vo, Richard T. Fox, Warren H. Griffin
  • Publication number: 20080299379
    Abstract: An improved energy absorbing member comprising, an thermoplastic cellular polymer in contact with a structural element such as a metal guard rail or automotive door, wherein the cellular polymer has an average cell size of at least about 0.75 mm and at least one of CE/CT, CV/CT and CH/CT is about 0.25 to about 0.4 said one of CE/CT, CV/CT and CH/CT having a compressive efficiency of at least 70% at a 60% strain, CE, CV and CH being the compressive strength of the cellular polymer in each of three orthogonal directions E, V and H where one of these directions is the direction of maximum compressive strength in the foam and CT equals the sum of CE, CV and CH.
    Type: Application
    Filed: May 30, 2008
    Publication date: December 4, 2008
    Inventors: Myron J. Maurer, Gavin D. Vogel, Byoung-Ho Choi, Warren H. Griffin, Kalyan Sehanobish
  • Patent number: 6599946
    Abstract: The present invention relates to blowing agent compositions for polymeric foams that contain carbon dioxide and a hydrofluorocarbon having a boiling point of 14° C. or higher and lower than about 120° C. The present invention also relates to processes for preparing polymeric foam using such blowing agent compositions, foamable polymer compositions containing such blowing agents, and polymeric foams containing such blowing agent compositions. Suitable blowing agent combinations include: (a) a composition containing carbon dioxide and at least one hydrofluorocarbon having a boiling point of 30° C. to about 120° C. that is essentially free of other low boiling ethers and hydrocarbons; (b) a composition containing greater than 50 weight-percent carbon dioxide and at least one hydrofluorocarbon having a boiling point of 14° C. or higher to about 120° C.; and (c) carbon dioxide and one hydrofluorocarbon having a boiling point of 14° C. or higher and lower than about 120° C.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: July 29, 2003
    Assignee: The Dow Chemical Company
    Inventors: John D. Duffy, Warren H. Griffin
  • Publication number: 20030119926
    Abstract: The present invention relates to blowing agent compositions for polymeric foams that contain carbon dioxide and a hydrofluorocarbon having a boiling point of 14° C. or higher and lower than about 120° C. The present invention also relates to processes for preparing polymeric foam using such blowing agent compositions, foamable polymer compositions containing such blowing agents, and polymeric foams containing such blowing agent compositions.
    Type: Application
    Filed: November 1, 2002
    Publication date: June 26, 2003
    Inventors: John D. Duffy, Warren H. Griffin
  • Patent number: 6476080
    Abstract: The present invention relates to blowing agent compositions that contain at least one hydrofluorocarbon having a boiling point of 30° C. or higher and lower than about 120° C., at least one hydrofluorocarbon having a boiling point lower than 30° C., and at least one component selected from low-boiling alcohols and low-boiling carbonyl compounds. The present invention also relates to processes for preparing polymeric foam using such blowing agent compositions, as well as polymeric foams and foamable polymer compositions containing such blowing agent compositions.
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: November 5, 2002
    Assignee: The Dow Chemical Company
    Inventors: John D. Duffy, Warren H. Griffin
  • Publication number: 20020161063
    Abstract: The present invention relates to blowing agent compositions for polymeric foams that contain carbon dioxide and a hydrofluorocarbon having a boiling point of 14° C. or higher and lower than about 120° C. The present invention also relates to processes for preparing polymeric foam using such blowing agent compositions, foamable polymer compositions containing such blowing agents, and polymeric foams containing such blowing agent compositions.
    Type: Application
    Filed: November 29, 2001
    Publication date: October 31, 2002
    Inventors: John D. Duffy, Warren H. Griffin
  • Publication number: 20020132868
    Abstract: The present invention relates to blowing agent compositions that contain at least one hydrofluorocarbon having a boiling point of 30° C. or higher and lower than about 120° C., at least one hydrofluorocarbon having a boiling point lower than 30° C., and at least one component selected from low-boiling alcohols and low-boiling carbonyl compounds. The present invention also relates to processes for preparing polymeric foam using such blowing agent compositions, as well as polymeric foams and foamable polymer compositions containing such blowing agent compositions.
    Type: Application
    Filed: November 29, 2001
    Publication date: September 19, 2002
    Inventors: John D. Duffy, Warren H. Griffin
  • Patent number: 5688832
    Abstract: Disclosed is a foam structure of desirable mechanical strength made with a low molecular weight alkenyl aromatic polymer material and an inorganic blowing agent. The polymer material has an alkenyl aromatic polymer of a weight average molecular weight of 100,000 to 165,000. The foam structure can be made in processes with reduced pressure drop.
    Type: Grant
    Filed: March 12, 1996
    Date of Patent: November 18, 1997
    Assignee: The Dow Chemical Company
    Inventors: Andrew N. Paquet, Warren H. Griffin
  • Patent number: 5286757
    Abstract: Disclosed is a process for making extruded, closed-cell alkenyl aromatic polymer foam structure having an average cell size of from about 0.3 to about 3.0 millimeters. The process comprises: a) heating an alkenyl aromatic polymer material having greater than 50 percent by weight alkenyl aromatic monomeric units to form a melt polymer material; b) incorporating into the melt polymer material at an elevated pressure a blowing agent comprising at least 50 percent by weight 1,1-difluoroethane (HFC-152a) based upon the total weight of the blowing agent to form a foamable gel; c) cooling the foamable gel to an optimum foaming temperature prior to extrusion through a die; and d) extruding the foamable gel through a die to form the foam structure. Further disclosed is a foamable gel capable of forming an alkenyl aromatic polymer foam structure having an average cell size of from about 0.3 to about 3.0 millimeters.
    Type: Grant
    Filed: May 24, 1993
    Date of Patent: February 15, 1994
    Assignee: The Dow Chemical Company
    Inventors: Roy E. Smith, Warren H. Griffin, Deborah L. Koesis, Dennis R. Lantz
  • Patent number: 5276063
    Abstract: Disclosed is a process for making extruded, closed-cell alkenyl aromatic polymer foam structure having an average cell size of from about 0.3 to about 3.0 millimeters. The process comprises: a) heating an alkenyl aromatic polymer material having greater than 50 percent by weight alkenyl aromatic monomeric units to form a melt polymer material; b) incorporating into the melt polymer material at an elevated pressure a blowing agent comprising at least 50 percent by weight 1,1-difluoroethane (HFC-152a) based upon the total weight of the blowing agent to form a foamable gel; c) cooling the foamable gel to an optimum foaming temperature prior to extrusion through a die; and d) extruding the foamable gel through a die to form the foam structure. Further disclosed is a foamable gel capable of forming an alkenyl aromatic polymer foam structure having an average cell size of from about 0.3 to about 3.0 millimeters.
    Type: Grant
    Filed: June 8, 1993
    Date of Patent: January 4, 1994
    Assignee: The Dow Chemical Company
    Inventors: Roy E. Smith, Warren H. Griffin, Deborah L. Kocsis, Dennis R. Lantz
  • Patent number: 5244928
    Abstract: Disclosed is a process for making extruded, closed-cell alkenyl aromatic polymer foam structure having an average cell size of from about 0.3 to about 3.0 millimeters. The process comprises: a) heating an alkenyl aromatic polymer material having greater than 50 percent by weight alkenyl aromatic monomeric units to form a melt polymer material: b) incorporating into the melt polymer material at an elevated pressure a blowing agent comprising at least 50 percent by weight 1,1-difluoroethane (HFC-152a) based upon the total weight of the blowing agent to form a foamable gel: c) cooling the foamable gel to an optimum foaming temperature prior to extrusion through a die: and d) extruding the foamable gel through a die to form the foam structure. Further disclosed is a foamable gel capable of forming an alkenyl aromatic polymer foam structure having an average cell size of from about 0.3 to about 3.0 millimeters.
    Type: Grant
    Filed: August 7, 1992
    Date of Patent: September 14, 1993
    Assignee: The Dow Chemical Company
    Inventors: Roy E. Smith, Warren H. Griffin, Deborah L. Kocsis, Dennis R. Lantz
  • Patent number: 4129530
    Abstract: Low density, closed cell, soft foam products having dimensional stability are made from ethylenic resins having low stiffness, especially comprising copolymers consisting essentially of ethylene and monoethylenically unsaturated non-ionic comonomers, by release to lower pressure of a flowable, foamable gel under pressure, e.g., by extrusion foaming, wherein the gel comprises the ethylenic polymer and a volatile mixed blowing agent. The starting polymers are preferably copolymers of ethylene and vinyl acetate having stiffness less than about 20,000 psi. The mixed blowing agents are particularly characterized as mixtures of dichlorodifluoromethane and at least one fluorocarbon constituent A, as defined. Exemplary mixtures contain (I) dichlorodifluoromethane and (II) from 35 to 50 percent chloropentafluoroethane, octafluoropropane or octafluorocyclobutane based on the mixtures of I and II.
    Type: Grant
    Filed: December 19, 1977
    Date of Patent: December 12, 1978
    Assignee: The Dow Chemical Company
    Inventors: Chung P. Park, John M. Corbett, Warren H. Griffin
  • Patent number: 4101467
    Abstract: Low density, closed cell, soft foam products having dimensional stability are made from ethylenic resins having low stiffness, especially comprising copolymers consisting essentially of ethylene and monoethylenically unsaturated non-ionic comonomers, by release to lower pressure of a flowable, foamable gel under pressure, e.g., by extrusion foaming, wherein the gel comprises the ethylenic polymer and a volatile mixed blowing agent. The stating polymers are preferably copolymers of ethylene and vinyl acetate having stiffness less than about 20,000 psi. The mixed blowing agents are particularly characterized as mixtures of at least one fluorocarbon constituent I and at least one fluorocarbon constituent II, as defined. Exemplary mixtures contain (I) 1,2-dichloro-1,1,2,2-tetrafluoroethane and (II) from 25 to 50 percent chloropentafluoroethane, octafluoropropane or octafluorocyclobutane based on the mixtures of I and II.
    Type: Grant
    Filed: January 27, 1977
    Date of Patent: July 18, 1978
    Assignee: The Dow Chemical Company
    Inventors: Chung Poo Park, Warren H. Griffin, John M. Corbett