Patents by Inventor Thirumurti Narayan

Thirumurti Narayan 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: 4677154
    Abstract: The invention relates to elimination of discoloration in polyurethanes, particularly thermoplastic polyurethanes, by the addition to the reaction mixture from 0.
    Type: Grant
    Filed: December 18, 1985
    Date of Patent: June 30, 1987
    Assignee: BASF Corporation
    Inventors: Thirumurti Narayan, Peter T. Kan
  • Patent number: 4636530
    Abstract: Flame retardant intumescent polyisocyanurate rigid foams are prepared by trimerizing isocyanate-terminated quasi-prepolymers containing predominately urethane linkages prepared by reacting an organic polyisocyanate with polyester polyols derived from the transesterification of dimethyl terephthalate process residue. The solvent blown rigid polyisocyanurate foams have exceptionally low friability.
    Type: Grant
    Filed: November 25, 1985
    Date of Patent: January 13, 1987
    Assignee: BASF Corporation
    Inventor: Thirumurti Narayan
  • Patent number: 4544763
    Abstract: Urethane-modified polyisocyanates prepared from toluene diisocyanate are desirable for economic, processing, and product property reasons. Such products should be low in viscosity to allow spray application and low in free TDI content to avoid undue physiological hazard.By use of prescribed reaction condition and reactant ratios, a suitable product can be prepared from hydroxyl-terminated polyoxyalkylene compounds, toluene diisocyanate, and diphenylmethane diisocyanate.
    Type: Grant
    Filed: October 19, 1984
    Date of Patent: October 1, 1985
    Assignee: Basf Wyandotte Corporation
    Inventor: Thirumurti Narayan
  • Patent number: 4525489
    Abstract: Reaction products of certain tertiary phosphines, alkylene oxides, and carboxylic acids have been found to be effective catalysts for the preparation of rigid and flexible foams characterized by isocyanurate and/or urethane linkages.
    Type: Grant
    Filed: August 28, 1981
    Date of Patent: June 25, 1985
    Assignee: BASF Wyandotte Corporation
    Inventor: Thirumurti Narayan
  • Patent number: 4490490
    Abstract: Enhanced load-bearing properties for flexible polyurethane foam can be achieved by employing a hydroxyl compound-modified benzyl ether-containing resole polyol as part of the polyol component (5 to 25 weight percent based on polyol) in the preparation of the foam.
    Type: Grant
    Filed: May 24, 1983
    Date of Patent: December 25, 1984
    Assignee: BASF Wyandotte Corporation
    Inventors: John T. Patton, Jr., Thirumurti Narayan, Louis H. Dumas
  • Patent number: 4482651
    Abstract: Haloalkoxymethylmelamine adduct is prepared by reacting hexamethoxymethylmelamine with a halogenated alcohol. Dispersions of this adduct in a polyol produce a polyurethane product which displays improved flame retardancy.
    Type: Grant
    Filed: December 1, 1982
    Date of Patent: November 13, 1984
    Assignee: BASF Wyandotte Corporation
    Inventors: Curtis J. Reichel, John T. Patton, Jr., Thirumurti Narayan
  • Patent number: 4455397
    Abstract: Polyisocyanurate foams are prepared from reacting partially etherified methylolmelamines either alone or in mixture with polyoxyalkylene polyether polyols with polyisocyanates. Improved friability and flame retardancy are obtained.
    Type: Grant
    Filed: September 14, 1983
    Date of Patent: June 19, 1984
    Assignee: BASF Wyandotte Corporation
    Inventors: Curtis J. Reichel, Thirumurti Narayan, John T. Patton, Jr.
  • Patent number: 4454254
    Abstract: Aminoplast resin is prepared by reacting urea or melamine with formaldehyde in the presence of a stabilizer compound. Dispersions of the resin in a polyol reacted with a polyisocyanate produce polyurethane products having low flammability properties.
    Type: Grant
    Filed: December 1, 1982
    Date of Patent: June 12, 1984
    Assignee: BASF Wyandotte Corporation
    Inventors: Curtis J. Reichel, John T. Patton, Jr., Thirumurti Narayan
  • Patent number: 4424288
    Abstract: Liquid carbodiimide-modified organic polyisocyanates are prepared by reacting a crude polymethylene polyphenylene polyisocyanate containing no more than 70 weight percent diphenylmethane diisocyanate with an isomer mixture of 40 to 100 weight percent 4,4'-, 0 to 50 weight percent 2,4- and 0 to 10 weight percent 2,2'-diphenylmethane diisocyanate and having an average functionality of 2.1 to 2.7 and a free NCO content of at least 30 percent weight percent in the presence of an effective amount of carbodimidization catalyst. Polyisocyanurate-polyurethane foams prepared by reacting the modified polyisocyanates and polyols selected from the group consisting of diethylene glycol and ethylene oxide adducts of trimethylolpropane, trimethylolethane, glycerine, pentaerythritol, .alpha.-methylglucoside, sucrose, toluene diamine and methylene dianiline in the presence of trimerization catalysts exhibit improved compression strengths and K-factors with low friability and smoke density.
    Type: Grant
    Filed: December 24, 1981
    Date of Patent: January 3, 1984
    Assignee: BASF Wyandotte Corporation
    Inventors: John T. Patton, Jr., Peter T. Kan, Thirumurti Narayan
  • Patent number: 4410641
    Abstract: Polyisocyanurate-polyurethane foams are prepared by reacting an organic polyisocyanate with oxyethylated aromatic amines and diols having equivalent weights from 31 to 100 and at an isocyanate index of 150 to 500 in the presence of a trimerization catalyst and a blowing agent.
    Type: Grant
    Filed: January 4, 1982
    Date of Patent: October 18, 1983
    Assignee: BASF Wyandotte Corporation
    Inventors: Thirumurti Narayan, Theodore O. Stolz, John T. Patton, Jr.
  • Patent number: 4386167
    Abstract: Polyisocyanurate polymers containing pendant urea groups are prepared by polymerization of polyisocyanates in organic solvents employing appropriate trimerization catalysts and then end-capping the polyisocyanurate polymer with ammonia or ammonium hydroxide. These end-capped polyisocyanurate polymers which contain pendant urea groups are dispersed in polyols to yield fine particulate dispersions. Cellular and non-cellular urethane products prepared using these dispersions displayed improved physical properties.
    Type: Grant
    Filed: April 19, 1982
    Date of Patent: May 31, 1983
    Assignee: BASF Wyandotte Corporation
    Inventors: John T. Patton, Jr., Thirumurti Narayan
  • Patent number: 4382125
    Abstract: A stable isocyanurate-modified polyisocyanate prepared by trimerizing an organic polyisocyanate mixture of 45 to 70 percent by weight of diphenylmethane diisocyanate having an isomer mixture of 40 to 100 weight percent, 4,4'-, 0 to 50 weight percent 2,4-, and 0 to 10 weight percent 2,2'-diphenylmethane diisocyanate and from 30 to 55 percent by weight polymethylene polyphenylene polyisocyanate with an isocyanurate content of 20 to 33 percent by weight. Polyurethane isocyanurate foams prepared from the reaction of these isocyanates with active hydrogen compounds selected from the group consisting of diethylene glycol and ethylene oxide adducts of trimethylolpropane, trimethylolethane, and glycerine exhibit good K- factors, low friability and low smoke density.
    Type: Grant
    Filed: November 30, 1981
    Date of Patent: May 3, 1983
    Assignee: BASF Wyandotte Corporation
    Inventors: Thirumurti Narayan, Peter T. Kan, John T. Patton, Jr.
  • Patent number: 4359541
    Abstract: Polyisocyanurate polymers are prepared by polymerization of polyisocyanates in organic solvents employing trimerization catalysts. The polyisocyanates are reacted with monofunctional active hydrogen compounds prior to polymerization or subsequent to the polymerization. These polymers may be dispersed in polyols for the preparation of cellular and non-cellular polyurethane products having improved physical properties.
    Type: Grant
    Filed: January 19, 1981
    Date of Patent: November 16, 1982
    Assignee: BASF Wyandotte Corporation
    Inventors: John T. Patton, Jr., Thirumurti Narayan, Gerhard G. Ramlow
  • Patent number: 4359550
    Abstract: Polyisocyanurate polymers are prepared by the polymerization of organic polyisocyanates in organic solvents employing trimerization catalysts. After deactivation of the catalysts and removal of the solvents, these polymers may be dispersed in polyols which are employed for the preparation of cellular and non-cellular polyurethane products displaying improved load bearing properties.
    Type: Grant
    Filed: January 19, 1981
    Date of Patent: November 16, 1982
    Assignee: BASF Wyandotte Corporation
    Inventors: Thirumurti Narayan, Gerhard G. Ramlow, Peter T. Kan
  • Patent number: 4349638
    Abstract: The subject invention relates to the use of alkali metal ammonium carboxylates as catalysts in the preparation of rigid and flexible foams characterized by isocyanurate and/or urethane linkages. Alkali metal ammonium carboxylates are the reaction products of a tertiary amine and an alkali metal acid salt of a polycarboxylic acid.
    Type: Grant
    Filed: November 2, 1981
    Date of Patent: September 14, 1982
    Assignee: BASF Wyandotte Corporation
    Inventor: Thirumurti Narayan
  • Patent number: 4326043
    Abstract: Polyisocyanurate polymers are prepared by polymerization of polyisocyanates in organic solvents employing trimerization catalysts. The polyisocyanates are reacted with halogenated alcohols subsequent to polymerization. These polymers may be dispersed in polyols for the preparation of cellular and non-cellular polyurethane products having improved flame retardant physical properties.
    Type: Grant
    Filed: January 19, 1981
    Date of Patent: April 20, 1982
    Assignee: BASF Wyandotte Corporation
    Inventors: Thirumurti Narayan, John T. Patton, Jr.
  • Patent number: 4284730
    Abstract: The invention relates to carbodiimide- and/or uretonimine-isocyanurate-containing polyisocyanates, to the process for their preparation, and to microcellular foams prepared therefrom.These compositions may be prepared in the presence of the appropriate catalyst by(a) a partial trimerization of a mixture of polyisocyanate and carbodiimide and uretonimine containing polyisocyanate with trimer catalyst to the desired free isocyanate level,(b) sequential, partial carbodiimidization followed by partial trimerization of a polyisocyanate to the desired free isocyanate level(c) sequential partial trimerization of a polyisocyanate followed by partial carbodiimidization,(d) simultaneous conversion using the mixed catalyst system of carbodiimide and isocyanurate catalysts reacted to the desired free isocyanate level, and(e) blending liquid polyisocyanate with the carbodiimide and uretonimine containing polyisocyanate and isocyanurate containing polyisocyanate to the desired isocyanate level.
    Type: Grant
    Filed: February 7, 1980
    Date of Patent: August 18, 1981
    Assignee: BASF Wyandotte Corporation
    Inventors: Thirumurti Narayan, Peter T. Kan
  • Patent number: 4243756
    Abstract: Isocyanurate-modified polyisocyanate compositions prepared by reacting organic polyisocyanates in the presence of catalytic amounts of alkali metal or alkaline earth metal organo-hydroxamates or the metal salt-free acid complex at temperatures from 25.degree. C. to 250.degree. C.
    Type: Grant
    Filed: August 27, 1979
    Date of Patent: January 6, 1981
    Assignee: BASF Wyandotte Corporation
    Inventors: Moses Cenker, Thirumurti Narayan
  • Patent number: 4228095
    Abstract: Carbodiimide-modified organic polyisocyanates are prepared by heating polyisocyanates in the presence of a catalytically sufficient amount of an organotin compound.
    Type: Grant
    Filed: August 20, 1979
    Date of Patent: October 14, 1980
    Assignee: BASF Wyandotte Corporation
    Inventor: Thirumurti Narayan
  • Patent number: 4197374
    Abstract: Stable, liquid polyisocyanate compositions are prepared by reacting a polyisocyanate or a mixture of polyisocyanates and halogen-containing carboxylic acids. The polyisocyanates hereof are used to prepare polyurethanes, polyisocyanurates, poly(isocyanurate-urethane) and the like. These isocyanates can be used in foam formation, films, fibers, coating solutions, elastomers and the like.
    Type: Grant
    Filed: September 18, 1978
    Date of Patent: April 8, 1980
    Assignee: BASF Wyandotte Corporation
    Inventors: Thirumurti Narayan, Harald P. Wulff