Patents by Inventor Frank E. Critchfield

Frank E. Critchfield 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: 6127443
    Abstract: Energy absorbing rigid polyurethane foams have both high energy absorbing efficiency as well as exceptional recovery after deformation, allowing their use in visible energy absorbing structures, particularly in the transportation vehicle industry. The foams are prepared by reaction of one or more di- or polyisocyanates with a polyol component containing both high and low molecular weight polyols, and optionally chain extenders, crosslinkers, and other additives, wherein at least one polyol is a polymer polyol such that the total vinyl polymer solids content of the foam is greater than 15 weight percent.
    Type: Grant
    Filed: November 6, 1998
    Date of Patent: October 3, 2000
    Assignee: Bayer Antwerp N.V.
    Inventors: Mark J. Perry, James L. Lambach, Frank E. Critchfield
  • Patent number: 5718856
    Abstract: High resilience polyurethane foams having improved wet set properties are obtained by reacting an isocyanate with a polyol component consisting of a polyoxyalkylene polyol with a functionality of 6 or more and a polymer polyol whose base polyol is a polyoxyalkylene polyol with a functionality of 6 or more, both polyols having oxyethylene caps in amounts of from 12 percent to about 30 percent based on the weights of the respective polyols, in the presence of an amine catalyst system. The resulting polyurethane foams are eminently suitable for seating cushions used in tropical or subtropical environments, may be prepared by a cold molding process, and may be used without an elevated temperature post cure.
    Type: Grant
    Filed: May 30, 1996
    Date of Patent: February 17, 1998
    Assignee: Arco Chemical Technology, L.P.
    Inventors: Mark R. Kinkelaar, Keith Douglas Cavender, James L. Lambach, Robert D. Brasington, Frank E. Critchfield
  • Patent number: 5668191
    Abstract: Cold molded flexible polyurethane foams may be prepared from low primary hydroxyl Polyoxyalkylene polyols when polyoxyalkylene polyols having an unsaturation of 0.02 meq/g or less provide the substantial portion of the polyol component.
    Type: Grant
    Filed: December 21, 1995
    Date of Patent: September 16, 1997
    Assignee: ARCO Chemical Technology, L.P.
    Inventors: Mark R. Kinkelaar, Frank E. Critchfield, James L. Lambach
  • Patent number: 5549841
    Abstract: High resilience polyurethane foams having improved wet set properties are obtained by reacting an isocyanate with a polyol component consisting of a polyoxyalkylene polyol with a functionality of 6 or more and a polymer polyol whose base polyol is a polyoxyalkylene polyol with a functionality of 6 or more, both polyols having oxyethylene caps in amounts of from 12 percent to about 30 percent based on the weights of the respective polyols, in the presence of an amine catalyst system. The resulting polyurethane foams are eminently suitable for seating cushions used in tropical or subtropical environments, may be prepared by a cold molding process, and may be used without an elevated temperature post cure.
    Type: Grant
    Filed: March 24, 1995
    Date of Patent: August 27, 1996
    Assignee: Arco Chemical Technology, L.P.
    Inventors: Mark R. Kinkelaar, Keith D. Cavender, James L. Lambach, Robert D. Brasington, Frank E. Critchfield
  • Patent number: 5496894
    Abstract: The present invention provides polymer polyols and a method for preparing polymer polyols which have (1) exceptional dispersion stability, especially at high styrene contents, and (2) substantially smaller particle sizes than polymer polyols having equivalent viscosity. In a preferred embodiment of the present invention, a first reaction product is obtained by feeding the following materials to a first continuous reactor in the presence of a free radical initiator or catalyst: (a) less than about 50 wt. % of a total monomer proportion or monomer mixture, preferably comprising styrene/acrylonitrile at a ratio preferably greater than about 50/50 wt. %; (b) at least about 50 wt. % of a total base polyol proportion; (c) a majority of a precursor stabilizer; and, (d) a polymer control agent (PCA).
    Type: Grant
    Filed: June 10, 1994
    Date of Patent: March 5, 1996
    Assignee: ARCO Chemical Technology, L.P.
    Inventors: Frank E. Critchfield, Donald W. Simroth, Stuart L. Watson
  • Patent number: 5395860
    Abstract: It has been discovered that particular flexible polyurethane foam formulations having a chlorinated alkane incorporated therein have the advantage of improved combustion resistance, but also unexpectedly the additional advantages of improved durability (dynamic fatigue), and better processing in terms of a delayed onset of gel. These results were surprisingly achieved with the use of a chlorinated alkane as the sole component to improve combustion resistance. Incorporation of as much as 34 parts of chlorinated alkane per hundred parts of polyol have been accomplished.
    Type: Grant
    Filed: December 23, 1993
    Date of Patent: March 7, 1995
    Assignee: Arco Chemical Technology, L.P.
    Inventors: Siusun K. Leung, Frank E. Critchfield, Paul M. Westfall
  • Patent number: 5364906
    Abstract: The present invention provides polymer polyols and a method for preparing polymer polyols which have (1) exceptional dispersion stability, especially at high styrene contents, and (2) substantially smaller particle sizes than polymer polyols having equivalent viscosity. In a preferred embodiment of the present invention, a first reaction product is obtained by feeding the following materials to a first continuous reactor in the presence of a free radical initiator or catalyst: (a) less than about 50 wt % of a total monomer proportion or monomer mixture, preferably comprising styrene/acrylonitrile at a ratio preferably greater than about 50/50 wt %; (b) at least about 50 wt % of a total base polyol proportion; (c) a majority of a precursor stabilizer; and, (d) a polymer control agent (PCA).
    Type: Grant
    Filed: August 20, 1993
    Date of Patent: November 15, 1994
    Assignee: Arco Chemical Technology, L.P.
    Inventors: Frank E. Critchfield, Donald W. Simroth, Stuart L. Watson
  • Patent number: 5084486
    Abstract: A process for manufacture of molded, high resiliency, polyurethane foam substantially free of volatile organic blowing agents comprising feeding at least three streams into a mixing device to form a reaction mixture, wherein a first stream contains (i) a polyol, (ii) water, (iii) a catalyst, (iv) a surfactant; a second stream contains an organic polyisocyanate; and a third stream contains (i) water, (ii) a crosslinking/extending agent, and (iii) a process/foam modifier.
    Type: Grant
    Filed: December 20, 1990
    Date of Patent: January 28, 1992
    Assignee: Union Carbide Chemicals & Plastics Technology Corporation
    Inventors: William Patten, Keith D. Cavender, Frank E. Critchfield
  • Patent number: 4902723
    Abstract: Hexahydro-s-triazines, and in particular hexamethylenetetramine (HMT), can be used in high water (5.0 or more parts per hundred parts of polyol) flexible polyurethane foams formulations in place of conventional gellation catalysts to produce open celled molded foams with excellent surfaces and with cores free of discoloration.
    Type: Grant
    Filed: November 7, 1988
    Date of Patent: February 20, 1990
    Assignee: Union Carbide Chemicals and Plastics Company Inc.
    Inventors: Otis M. Baker, Frank E. Critchfield, Paul M. Westfall
  • Patent number: 4883825
    Abstract: A process for the manufacture of low density flexible polymethane foam via a catalyzed reaction of a highly reactive, high ethylene oxide, high functionality polyol, a hydrophilic polyhydric compound, water and polyisocyanates.
    Type: Grant
    Filed: December 30, 1987
    Date of Patent: November 28, 1989
    Assignee: Union Carbide Chemicals and Plastics Company Inc.
    Inventors: Paul M. Westfall, Frank E. Critchfield, William A. Gill
  • Patent number: 4814359
    Abstract: Hexahydro-s-triazines, and in particular hexamethylenetetramine (HMT), can be used in high water (5.0 or more parts per hundred parts of polyol) flexible polyurethane foams formulations in place of conventional gellation catalysts to produce open celled molded foams with excellent surfaces and with cores free of discoloration.
    Type: Grant
    Filed: December 30, 1987
    Date of Patent: March 21, 1989
    Assignee: Union Carbide Corporation
    Inventors: Otis M. Baker, Frank E. Critchfield, Paul M. Westfall
  • Patent number: 4797501
    Abstract: This invention relates to silicon-based polymer/polyol stabilizers, processes for their manufacture and polyurethane foams containing these stabilized polymer polyols.
    Type: Grant
    Filed: October 13, 1987
    Date of Patent: January 10, 1989
    Assignee: Union Carbide Corporation
    Inventors: Richard C. Myerly, Michael W. Jorgenson, Frank E. Critchfield
  • Patent number: 4652589
    Abstract: A normally liquid, stable polymer/polyol composition which imparts improved combustion resistance to polyurethane foams prepared therefrom while retaining satisfactory foam tensile properties are formed by polymerizing in the presence of a free radical catalyst and in the essential absence of an alkyl mercaptan, (1) from about 25 to about 60 weight percent of an ethylenically unsaturated monomer or monomers, for example, a mixture of acrylonitrile and styrene in a weight ratio respectively of 25:75 to 0:100, dissolved or dispersed in (2) from about 40 to about 75 weight percent of a polyol comprising a base polyol having a hydroxyl number of less than about 150, wherein the polymer is characterized by a crosslinking coefficient of less than 55 and an intrinsic viscosity of at least 0.30.
    Type: Grant
    Filed: February 8, 1985
    Date of Patent: March 24, 1987
    Assignee: Union Carbide Corporation
    Inventors: Donald W. Simroth, Frank E. Critchfield, Richard C. Myerly
  • Patent number: 4463107
    Abstract: A stable dispersion of a polymer in a polyol which imparts improved combustion resistance to polyurethane foams prepared therefrom wherein the polymer is a free-radical initiated copolymer containing from about 0.5 to 75 weight percent, based on the copolymer, of acrylonitrile and from about 25 to 99.5 weight percent, based on the copolymer, of at least one other polymerizible ethylenically unsaturated monomer and wherein the copolymer is characterized by a crosslinking coefficient of less than 55.
    Type: Grant
    Filed: August 18, 1982
    Date of Patent: July 31, 1984
    Assignee: Union Carbide Corporation
    Inventors: Donald W. Simroth, Frank E. Critchfield, Edgar G. Shook
  • Patent number: 4312973
    Abstract: The invention provides polyurethane elastomers having satisfactory modulus characteristics which are prepared from a polyol-chain extender mixture consisting of (1) a poly (oxypropylene-oxyethylene) polyol having a hydroxyl number of from about 20 to 60, an oxyethylene cap of from about 10 to 30 weight percent and an internal oxyethylene content of from about 30 to 60 weight percent and (2) ethylene glycol, or a polymer/polyol-chain extender mixture wherein the polyol-chain extender is as aforesaid, and the resulting polyurethane elastomers possess unexpected hydrolytic stability.
    Type: Grant
    Filed: April 11, 1980
    Date of Patent: January 26, 1982
    Assignee: Union Carbide Corporation
    Inventors: Frank E. Critchfield, Richard M. Gerkin, Leslie E. Hawker
  • Patent number: 4283500
    Abstract: Novel improved polymer/polyisocyanate composition made by polymerizing acrylonitrile alone or with one or more ethylenically unsaturated monomers in situ in a polyisocyanate. The polyisocyanate comprises a diarylalkylene diisocyanate; a polymeric diarylalkylene polyisocyanate; a quasi-prepolymer of a diarylalkylene diisocyanate or a polymeric diarylalkylene diisocyanate with an active hydrogen organic compound having at least two active hydrogen atoms per molecule; a mixture of a diarylalkylene diisocyanate, its carbodiimide and its trifunctional trimeric cycloadduct; or a mixture of two or more such polyisocyanates, to form a highly stable dispersion of small polymer particles in said polyisocyante. The novel compositions are highly useful in the production of polyurethane products.
    Type: Grant
    Filed: March 31, 1980
    Date of Patent: August 11, 1981
    Assignee: Union Carbide Corporation
    Inventors: George H. Armstrong, Richard M. Gerkin, Frank E. Critchfield
  • Patent number: 4226756
    Abstract: The invention provides a polyol-chain extender mixture consisting of (1) a poly(oxypropylene-oxyethylene) polyol having a hydroxyl number of from about 20 to 60, an oxyethylene cap of from about 10 to 30 weight percent and an internal oxyethylene content of from about 30 to 60 weight percent and (2) ethylene glycol,The invention also provides polymer/polyoly-chain extender mixtures wherein the polyol-chain extender is as aforesaid.
    Type: Grant
    Filed: August 10, 1978
    Date of Patent: October 7, 1980
    Assignee: Union Carbide Corporation
    Inventors: Frank E. Critchfield, Richard M. Gerkin, Leslie E. Hawker
  • Patent number: 4190711
    Abstract: Thermoplastic polyether polyurethane elastomers are provided by reacting and forming: (a) a novel liquid polyurethane quasi-prepolymer having a free NCO content of from about 16 percent to about 25 percent; (b) a reactive poly(oxypropylene-oxyethylene) diol; and (c) as an extender, a short chain diol in the presence of (d) a catalyst. The elastomers can be either solid or microcellular, and they are suitable for production using Reaction Injection Molding (RIM) or conventional casting technology. The elastomers are useful in the production of automotive body panels, gears, seals and the like, and, since the elastomers are thermoplastic, any excess elastomer ("scrap") can be reused.
    Type: Grant
    Filed: September 29, 1977
    Date of Patent: February 26, 1980
    Assignee: Union Carbide Corporation
    Inventors: Richard J. Zdrahala, Frank E. Critchfield
  • Patent number: 4125505
    Abstract: Poly (oxypropylene-oxyethylene) polyols containing predetermined amounts of both internal and cap ethylene oxide are employed to form polymer/polyols which exhibit enhanced compatibility for low molcular weight chain extenders such as, for example, ethylene glycol and butanediol. Polyurethane elastomers having satisfactory modulus characteristics are prepared from the polymer/polyol-chain extender mixture, and the resulting elastomers possess unexpected hydrolytic stability.
    Type: Grant
    Filed: July 6, 1976
    Date of Patent: November 14, 1978
    Assignee: Union Carbide Corporation
    Inventors: Frank E. Critchfield, Richard M. Gerkin, Leslie E. Hawker
  • Patent number: RE32733
    Abstract: A stable dispersion of a polymer in a polyol which imparts improved combustion resistance to polyurethane foams prepared therefrom wherein the polymer is a free-radical initiated copolymer containing from about 0.5 to 75 weight percent, based on the copolymer, of acrylonitrile and from about 25 to 99.5 weight percent, based on the copolymer, of at least one other polymerizible ethylenically unsaturated monomer and wherein the copolymer is characterized by a crosslinking coefficient of less than 55.
    Type: Grant
    Filed: December 12, 1985
    Date of Patent: August 16, 1988
    Assignee: Union Carbide Corporation
    Inventors: Donald W. Simroth, Frank E. Critchfield, Edgar G. Shook