Patents by Inventor Robert E. Hefner, Jr.

Robert E. Hefner, Jr. 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).

  • Stilbene-based polyester and polycarbonate compositions
    Patent number: 5614599
    Abstract: Described is a polycarbonate, polyester, or polyestercarbonate composition prepared from a reaction mixture comprising at least one diol and at least one carbonate precursor or ester precursor, wherein at least about 95 mole percent of the diol present in the reaction mixture consists of one or more aromatic diols, at least about 10 mole percent of which consists of one or more stilbene diols. The composition of the invention advantageously has a relatively high thermal resistance, melting temperature, tensile and flexural properties, and/or resistance to thermal embrittlement. Moreover, the polymers of the invention which are thermotropic liquid crystalline also advantageously possess a broad temperature range for liquid crystallinity, good melt processibility, a low coefficient of thermal expansion, a high ignition resistance, high solvent resistance, and/or good barrier properties.
    Type: Grant
    Filed: October 13, 1995
    Date of Patent: March 25, 1997
    Assignee: The Dow Chemical Company
    Inventors: Stephen E. Bales, Robert E. Hefner, Jr., Rina Singh
  • Polyphenols containing mesogenic moieties as lateral substituents
    Patent number: 5612479
    Abstract: Novel polycyanate compositions containing one or more mesogenic moieties as lateral substituents are disclosed which provide improved processability relative to polycyanates containing one or more mesogenic moieties in the main chain of the molecule. Molecular level ordering of the resulting thermosets is maintained much similar to that found thermosets of polycyanates which have one or more mesogenic moieties in the main chain.
    Type: Grant
    Filed: August 17, 1994
    Date of Patent: March 18, 1997
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls
  • Adducts of epoxy resins and active hydrogen containing compounds containing mesogenic moieties
    Patent number: 5602211
    Abstract: Adducts containing mesogenic or rodlike moieties are prepared by reacting (1) at least one compound containing an average of more than one vicinal epoxide group per molecule with (2) at least one compound containing an average of more than one reactive hydrogen atom per molecule; with the proviso that at least one member of components (1) and (2) contains a mesogenic or rodlike moiety. These compounds are useful as curing agents for epoxy resins.
    Type: Grant
    Filed: January 18, 1995
    Date of Patent: February 11, 1997
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls
  • Mesogen-containing aromatic anhydride compounds
    Patent number: 5541323
    Abstract: Anhydride compounds which contain at least one rodlike mesogenic moiety and at least two anhydride groups per molecule, wherein each of said aromatic anhydride groups is linked to the mesogen via an ester linkage are prepared. These anhydride compounds are useful in curing epoxy resins to provide the cured products with one or more improved properties.
    Type: Grant
    Filed: January 18, 1995
    Date of Patent: July 30, 1996
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls
  • Cure controlled catalyzed mixtures of epoxy resins and curing agents containing mesogenic moieties
    Patent number: 5510431
    Abstract: Curable compositions containing (A) one or more epoxy resins, one (B) or more curing agents and (C) one or more cure controlling catalysts wherein at least one of components (A) or (B) or both components (A) and (B) contain a mesogenic moiety are prepared. These curable compositions permit processing at higher temperatures and improved properties. They are useful in the preparation of coatings, castings, electrical or laminates or composites and the like.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: April 23, 1996
    Assignee: The Dow Chemical Company
    Inventors: Jimmy D. Earls, Robert E. Hefner, Jr., James L. Bertram, Louis L. Walker
  • Mesogenic cyclic imino ether-containing compositions and polymerization products thereof
    Patent number: 5491201
    Abstract: Novel cyclic imino ether compositions containing one or more mesogenic moieties, when polymerized, result in products having improved properties.
    Type: Grant
    Filed: February 16, 1995
    Date of Patent: February 13, 1996
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls
  • Mesogenic novolacs and resins
    Patent number: 5486580
    Abstract: The present invention discloses novolacs and thermosets thereof containing mesogenic moieties. Certain of said novolacs and thermosets thereof exhibit nonlinear optical properties upon orientation.
    Type: Grant
    Filed: November 2, 1994
    Date of Patent: January 23, 1996
    Assignee: The Dow Chemical Company
    Inventors: Mark D. Newsham, Jimmy D. Earls, Robert E. Hefner, Jr.
  • Preparation of 4,4'-dihydroxy-alpha'-dialkylstilbenes and 4, 4'-dihydroxy-alpha'-dialkylstilbenes
    Patent number: 5475155
    Abstract: 4,4'-Dihydroxy-alpha-alkylstilbenes of high purity are prepared by reacting at a temperature of from about -20.degree. C. to about 20.degree. C. a mixture of (1) at least one alpha-haloketone, (2) at least one phenolic hydroxyl-containing compound or alkoxy-containing aromatic compound, and (3) at least one strong protonic acid or Lewis acid; such that the mole ratio of phenolic hydroxyl-containing compound or alkoxy-containing aromatic compound:alpha-haloketone(s) is from 0.1:1 to 1.9:1, and the mole ratio of phenolic hydroxyl-containing compound or alkoxy-containing aromatic compound:alpha-haloketone(s):strong protonic acid or Lewis acid is from about 0.1:1:0.0026 to about 1.9:1:0.95. The high purity 4,4'-dihydroxy-alpha-alkylstilbenes are useful for the advancement of epoxy resins, for the preparation of phenoxy resins and for the preparation of epoxy resins.
    Type: Grant
    Filed: January 18, 1995
    Date of Patent: December 12, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Maria I. Villarreal, David A. Carr
  • Products resulting from polymerizing or curing polycyanates containing mesogenic moieties as lateral substituents
    Patent number: 5470946
    Abstract: Novel polycyanate compositions containing one or more mesogenic moieties as lateral substituents are disclosed which provide improved processability relative to polycyanates containing one or more mesogenic moieties in the main chain of the molecule. Molecular level ordering of the resulting thermosets is maintained much similar to that found thermosets of polycyanates which have one or more mesogenic moieties in the main chain.
    Type: Grant
    Filed: October 12, 1994
    Date of Patent: November 28, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls
  • Amines from nitro group terminated mesogenic epoxy resin adducts with reduced hydroxyl group functionality
    Patent number: 5464912
    Abstract: Adducts containing terminating nitro (nitroso) groups and one or more mesogenic moleties are prepared by reacting (A) at least one compound containing an average of more than one vicinal epoxide group per molecule with (B) at least one compound containing one or more nitro (nitroso) groups and an average of one reactive hydrogen atom per molecule; with the proviso that at least one member of components (A) and (B) contains a mesogenic moiety. Reaction of part or all of the aliphatic hydroxyl backbone groups by etherification, conversion to a halide, urethanation, oxidation to a ketone, or reduction of said ketone to an alkane, decreases the amount of hydroxyl group functionality. Reduction of these adducts provides amines which are useful as curing agents for epoxy resins.
    Type: Grant
    Filed: January 23, 1995
    Date of Patent: November 7, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls
  • Diglycidyl ether of 4,4'-dihydroxy-.alpha.-methylstilbene
    Patent number: 5463091
    Abstract: The diglycidyl ether of 4,4'-dihydroxy-.alpha.-methylstilbene is prepared.
    Type: Grant
    Filed: June 2, 1994
    Date of Patent: October 31, 1995
    Assignee: The Dow Chemical Company
    Inventors: Jimmy D. Earls, Robert E. Hefner, Jr., Paul M. Puckett
  • Mesogen-containing biaxially oriented films
    Patent number: 5460860
    Abstract: Mesogen containing biaxially oriented films are prepared from curable mixtures containing an epoxy resin and a curing agent therefor. Certain of the mesogen containing biaxially oriented films possess unique properties, such as a metallic like, highly reflective appearance. These films are useful in adhesives, coatings, laminates or composites and the like.
    Type: Grant
    Filed: May 20, 1994
    Date of Patent: October 24, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls, Peter E. Pierini, David A. Waldman, Lalitha Reddy
  • Cure controlled catalyzed mixtures of epoxy resins and curing agents containing mesogenic moieties, B-staged and cured products therefrom
    Patent number: 5458929
    Abstract: Laminates containing one or more plies of substrate material impregnated with a composition containing (A) one or more epoxy resins, (B) one or more curing agent and (C) about 0.00005 to about 0.1 mole per epoxide equivalent of cure controlling catalyst, wherein at least one of components (A) or (B) contain at least one mesogenic moiety, which, optionally, has been subjected to either (a) the application of an electric field, (b) the application of a magnetic field, (c) drawing or shear forces, or (d) any combination thereof, are prepared.
    Type: Grant
    Filed: February 15, 1994
    Date of Patent: October 17, 1995
    Assignee: The Dow Chemical Company
    Inventors: Jimmy D. Earls, Robert E. Hefner, Jr., James L. Bertram, Louis L. Walker, William A. Clay
  • Mesogenic polycyanates and thermosets thereof
    Patent number: 5442039
    Abstract: Novel polycyanate and polycyanamide compositions containing one or more rodlike mesogenic moieties, when cured, result in products having improved properties.
    Type: Grant
    Filed: July 13, 1993
    Date of Patent: August 15, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls, Paul M. Puckett
  • Mesogenic polycyanates and thermosets thereof
    Patent number: 5428125
    Abstract: Novel polycyanate and polycyanamide compositions containing one or more rodlike mesogenic moieties, when cured, result in products having improved properties.
    Type: Grant
    Filed: June 17, 1994
    Date of Patent: June 27, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls, Paul M. Puckett
  • Rodlike mesogenic thiirane resins (polythiiranes)
    Patent number: 5424393
    Abstract: Polythiirane resins are disclosed which contain at least one, rodlike mesogenic moiety. These resins can be cured by conventional curing agents typically employed to cure epoxy resins or they can be thermally cured without a curing agent.
    Type: Grant
    Filed: August 24, 1994
    Date of Patent: June 13, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls
  • Preparation of 4,4'-dihydroxy-alpha-alkylstilbenes and 4,4'-dihydroxy-alpha, alpha'-dialkylstilbenes
    Patent number: 5414150
    Abstract: 4,4'-Dihydroxy-alpha-alkylstilbenes of high purity are prepared by reacting at a temperature of from about -20.degree. C. to about 20.degree. C. a mixture of (1) at least one alpha-haloketone, (2) at least one phenolic hydroxyl-containing compound or alkoxy-containing aromatic compound, and (3) at least one strong protonic acid or Lewis acid; such that the mole ratio of phenolic hydroxyl-containing compound or alkoxy-containing aromatic compound:alpha-haloketone(s) is from 0.1:1 to 1.9:1, and the mole ratio of phenolic hydroxyl-containing compound or alkoxy-containing aromatic compound:alpha-haloketone(s):strong protonic acid or Lewis acid is from about 0.1:1:0.0026 to about 1.9:1:0.95. The high purity 4,4'-dihydroxy-alpha-alkylstilbenes are useful for the advancement of epoxy resins, for the preparation of phenoxy resins and for the preparation of epoxy resins.
    Type: Grant
    Filed: December 3, 1993
    Date of Patent: May 9, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Maria I. Villarreal, David A. Carr
  • Diamino-alpha-alkylstilbenes
    Patent number: 5414125
    Abstract: A diamino-alpha-alkylstilbene useful as an epoxy resin curing agent is represented by the following Formula I: ##STR1## wherein R is independently hydrogen, a C.sub.1 -C.sub.10 hydrocarbyl(oxy) group or a halogen, nitro, nitrile, phenyl or --CO--R.sup.1 group wherein R.sup.1 is independently hydrogen or a C.sub.1 -C.sub.3 hydrocarbyl group; each R.sup.4 is independently hydrogen or a C.sub.1 -C.sub.10 hydrocarbyl group; and Y is a ##STR2## group wherein n=0 or 1.
    Type: Grant
    Filed: July 23, 1993
    Date of Patent: May 9, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls
  • Adducts of epoxy resins and active hydrogen containing compounds containing mesogenic moieties
    Patent number: 5414121
    Abstract: Adducts containing mesogenic or rodlike moieties are prepared by reacting (1) at least one compound containing an average of more than one vicinal epoxide group per molecule with (2) at least one compound containing an average of more than one reactive hydrogen atom per molecule; with the proviso that at least one member of components (1) and (2) contains a mesogenic or rodlike moiety. These compounds are useful as curing agents for epoxy resins.
    Type: Grant
    Filed: September 8, 1993
    Date of Patent: May 9, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls
  • Nitro group terminated mesogenic epoxy resin adducts
    Patent number: 5412044
    Abstract: Adducts containing terminating nitro (nitroso) groups and one or more mesogenic moieties are prepared by reacting (A) at least one compound containing an average of more than one vicinal epoxide group per molecule with (B) at least one compound containing one or more nitro (nitroso) groups and an average of one reactive hydrogen atom per molecule; with the proviso that at least one member of components (A) and (B) contains a mesogenic moiety. Reduction of these adducts provides amines which are useful as curing agents for epoxy resins.
    Type: Grant
    Filed: May 12, 1994
    Date of Patent: May 2, 1995
    Assignee: The Dow Chemical Company
    Inventors: Robert E. Hefner, Jr., Jimmy D. Earls