Patents Represented by Attorney J. M. Hunter, Jr.
  • Patent number: 5208298
    Abstract: A stable solution of polybenzimidazole resin containing from approximately 10 to approximately 35 weight percent of resins and from approximately 65 to approximately 90 weight percent of a suitable solvent, the resins consist of from approximately 70 to approximately 95 weight percent of polybenzimidazole and from approximately 5 to approximately 30 weight percent of polysulfone, wherein the solution is substantially free of organic salt. The solution is useful for the production of films, fibers and molded articles exhibiting enhanced mechanical properties.
    Type: Grant
    Filed: April 8, 1992
    Date of Patent: May 4, 1993
    Assignee: Hoechst Celanese Corp.
    Inventors: Tai-Shung Chung, Arthur G. Schlask, Dieter Kurschus
  • Patent number: 5204443
    Abstract: A melt processable poly(ester-amide) which is capable of forming an anisotropic melt phase is provided. A poly(ester-amide) of the present invention may have recurring units of: (a) 4-hydroxybenzoyl moiety, (b) 6-oxy-2-naphthoyl moiety, (c) 4,4'-biphenol moiety, (d) terephthaloyl moiety, and (e) an aromatic moiety capable of forming an amide linkage in the proportions indicated. Preferably, the moiety capable of forming an amide linkage is derived from p-aminophenol, p-phenylenediamine, N-acetyl-p-aminophenol, etc. The resulting poly(ester-amide) is capable of undergoing melt-processing in the temperature range of from about 300.degree. to about 400.degree. C.
    Type: Grant
    Filed: April 19, 1991
    Date of Patent: April 20, 1993
    Assignee: Hoechst Celanese Corp.
    Inventors: Cherylyn Lee, Larry F. Charbonneau
  • Patent number: 5130481
    Abstract: Nitro dinitro and diamino compounds having the formula: ##STR1## wherein A is selected from the group consisting of SO.sub.2 ; O, S, CO, C.sub.1 to C.sub.6 alkylene, perfluoroalkylene or perfluoroarylalkylene having from 1 to 10 carbon atoms, and a carbon-carbon bond directly linking the two aromatic groups, R is selected from the group consisting of hydrogen, hydroxy and C.sub.1 to C.sub.4 alkoxy, and R' is selected from the group consisting of NO.sub.2 and NH.sub.2.In the most preferred embodiment, the A linking group is selected from hexafluoroisopropylidene or 1-phenyl-2,- 2,2-trifluoroethane, and R is hydroxy.The compounds of the present invention, where R' is NH.sub.2, may be used as crosslinking agents for epoxy resins and for unsaturated elastomers, or as a reactant monomer with an organic diacid or dianhydride co-reactant monomer in the preparation of polyamide, polyimide, polyamide-imide and polybenzoxazole polymers having superior thermal and mechanical properties.
    Type: Grant
    Filed: January 4, 1991
    Date of Patent: July 14, 1992
    Assignee: Hoechst Celanese Corporation
    Inventors: Dinesh N. Khanna, William R. Lee
  • Patent number: 5120826
    Abstract: The present invention provides for a novel heat stable class of polyamide-imide polymers having excellent flow properties and hydrolytic stability which are prepared by forming the polycondensation product of one or more aromatic or aliphatic diamines and a comonomer comprising a tri- or hexafluoro-substituted tricarboxylic acid anhydride (or acid derivative thereof) having the structure: ##STR1## wherein R is CF.sub.3 or a phenyl radical. In addition to improved flow properties, the polyamide-imide polymers of this invention also exhibit improved solubility properties in most organic solvents, good resistance to attack by chlorinated solvents such as trichloroethylene as compared with polyimides, improved hydrophobic properties as well as good thermal properties, including resistance to thermooxidative degradation.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: June 9, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Rohitkumar H. Vora, Paul N. Chen, Sr.
  • Patent number: 5120825
    Abstract: The present invention provides for hybrid polybenzimidazole and polybenzimidazolone polymers which are characterized as containing both imidazole and imidazolone structural units in the polymer chain. These polymers are characterized as containing at least one recurring monomer unit containing the structure of the formula: ##STR1## wherein Ar is a tetravalent aromatic moiety derived from an aromatic tetraamine and Ar.sub.1 is a trivalent aromatic moiety derived from a trifunctional acid, an acid anhydride or amine-reactive derivatives thereof, said polymers further characterized by an inherent viscosity of at least about 0.01 dl/g measured as a 0.5% solution in N-methyl pyrrolidone at 25.degree. C.The polymers of this invention exhibit many of the advantageous properties of both polybenzimidazole and polybenzimidazolone polymers. They are characterized as being extremely resistant to chemical attack such as by solvents, acids and bases.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: June 9, 1992
    Assignee: Hoechst Celanese Corp.
    Inventors: Rohitkumar H. Vora, Paul N. Chen, Sr.
  • Patent number: 5109107
    Abstract: The present invention provides for a novel heat stable class of polyamide-imide polymers having excellent flow properties and hydrolytic stability which are prepared by forming the polycondensation product of one or more aromatic or aliphatic diamines, one or more additional comonomers selected from the group consisting of a tetrafunctional aromatic dianhydride, an aromatic or aliphatic dicarboxylic acid (or acid derivative thereof) and mixtures thereof, and a comonomer comprising a tri- or hexafluoro-substituted tricarboxylic acid anhydride (or acid derivative thereof) having the structure: ##STR1## wherein Z is CF.sub.3 or a phenyl radical.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: April 28, 1992
    Assignee: Hoecht Celanese Corp.
    Inventors: Rohitkumar H. Vora, Paul N. Chen, Sr.
  • Patent number: 5109101
    Abstract: Thermoplastic polyarylate compositions suitable for molding are formed from isophthalic acid, terephthalic acid or mixtures thereof, a bisphenolic compound such as bisphenol A and from about 5 to 10 mole % relative to the monomeric charge of 2-hydroxy-6-naphthoic acid.
    Type: Grant
    Filed: January 23, 1991
    Date of Patent: April 28, 1992
    Assignee: Hoechst Celanse Corp.
    Inventors: Balaram Gupta, Gordon W. Calundann
  • Patent number: 5077383
    Abstract: New polybenzimidazolone polymers produced from the reaction of an aromatic tetraamine with a hexafluoro dianhydride. These hexafluoro polybenzimidazolone polymers based on an aromatic hexafluoro dianhydrides show improved solubility, easy processability, low moisture uptake, high thermal stability, resistance to solvent and other improvements over conventional polybenzimidazolone polymers.
    Type: Grant
    Filed: March 15, 1990
    Date of Patent: December 31, 1991
    Assignee: Hoechst Celanese Corp.
    Inventors: Rohitkumar H. Vora, Paul N. Chen, Sr., Joseph D. Menczel
  • Patent number: 5075419
    Abstract: This invention discloses new polybenzimidazolone polymers produced by the reaction of a hexafluoro aromatic tetraamine with a dianhydride reactant. These hexafluoro polybenzimidazolone polymers based on an aromatic hexafluoro tetraamine show improved solubility, easy processability, low moisture uptake, high thermal stability, resistance to solvent and other improvements over conventional polybenzimidazolone polymers.
    Type: Grant
    Filed: April 6, 1990
    Date of Patent: December 24, 1991
    Assignee: Hoechst Celanese Corp.
    Inventors: Rohitkumar H. Vora, Chen, Sr. Paul N., Joseph D. Menczel