Patents by Inventor Billie B. Dadgar

Billie B. Dadgar 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: 6521714
    Abstract: Novel brominated styrenic polymers having superior properties rendering them ideally suited for current commercial requirements for use as flame retardants in thermoplastic polymers are described. These properties include such high thermal stabilities in a standard Thermal Stability Test as to dramatically reduce if not eliminate the possibility of corrosion problems due to release of hydrogen halide at elevated polymer processing temperatures. Other special properties of the novel brominated styrenic polymers include, for example, low color or staining properties, and excellent melt flow characteristics.
    Type: Grant
    Filed: March 12, 2001
    Date of Patent: February 18, 2003
    Assignee: Albemarle Corporation
    Inventors: Charles H. Kolich, Billie B. Dadgar, Donald E. Balhoff, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 6399685
    Abstract: Emulsion formation is minimized or prevented and hydrolytic product degradation is suppressed during purification of impure bisphenol-A bis(diphenylphosphate). This is accomplished by forming a hydrocarbon solution of bisphenol-A bis(diphenylphosphate) plus impurities in a solvent comprising at least one aromatic hydrocarbon and at least one paraffinic hydrocarbon. Optionally, but preferably, this solution is washed with water or an aqueous buffer solution. Next, the hydrocarbon solution is washed one or more times with an aqueous alkaline washing solution that has a specific gravity that differs from the specific gravity of the hydrocarbon solution by at least about 0.05 gram per cubic centimeter. After each washing the mixture settles into a purified organic phase and a separate aqueous phase, and these phases are separated from each other.
    Type: Grant
    Filed: December 11, 2000
    Date of Patent: June 4, 2002
    Assignee: Albemarle Corporation
    Inventors: W. Dirk Klobucar, William B. Harrod, Billie B. Dadgar, Joseph D. McLean, Gary D. Heidebrecht, Hao V. Phan, Thomas R. Nicholas, Jeffrey L. Broeker
  • Publication number: 20020061983
    Abstract: Novel brominated styrenic polymers having superior properties rendering them ideally suited for current commercial requirements for use as flame retardants in thermoplastic polymers are described. These properties include such high thermal stabilities in a standard Thermal Stability Test as to dramatically reduce if not eliminate the possibility of corrosion problems due to release of hydrogen halide at elevated polymer processing temperatures. Other special properties of the novel brominated styrenic polymers include, for example, low color or staining properties, and excellent melt flow characteristics.
    Type: Application
    Filed: March 12, 2001
    Publication date: May 23, 2002
    Inventors: Charles H. Kolich, Billie B. Dadgar, Donald E. Balhoff, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 6326439
    Abstract: This invention relates to a thermally stable brominated polystyrene having less than 100 ppm total Cl−, above about 68 wt % bromine and less than about 6,000 ppm hydrolyzable halide. The brominated polystyrene exhibits little or no polymer cross-linking or chain cleavage relative to the starting polystyrene.
    Type: Grant
    Filed: September 15, 1998
    Date of Patent: December 4, 2001
    Assignee: Albemarle Corporation
    Inventors: Billie B. Dadgar, Donald E. Balhoff, Charles H. Kolich, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 6235844
    Abstract: These novel brominated styrenic polymers have a bromine content in the range of about 60 to about 66 wt % bromine; a total chlorine content, if any, of less than 700 ppm; a GPC weight average molecular weight in the range of about 500,000 to about 800,000; a DSC glass transition temperature of less than 175° C.; and a thermal stability in the Thermal Stability Test of 250 ppm HBr or less. Such flame retardant polymers exhibit superior performance qualities during use, especially in thermoplastics, including improved melt flow characteristics and improved thermal stability.
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: May 22, 2001
    Assignee: Albemarle Corporation
    Inventors: Billie B. Dadgar, Donald E. Balhoff, Charles H. Kolich, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 6235831
    Abstract: A polyalkylene terephthalate polymer, such as polyethylene terephthalate, polybutylene terephthalate, blends or copolymers thereof, and analogous polyester-type engineering thermoplastics, with which has been blended a flame retardant amount of brominated styrenic polymer, such as brominated polystyrene, that, prior to blending, is characterized by (a) containing less than 700 ppm Cl and having a TGA temperature for 1% weight loss of 340° C. or higher; and/or (b) having an actual Mw which is within about 20%, and preferably within about 10%, of its calculated theoretical Mw, the theoretical Mw being based upon the actual bromine content of the brominated styrenic polymer and the Mw of the styrenic polymer reactant used to produce the brominated styrenic polymer; and/or (c) being essentially free of each of the following impurities: (1) ethylene dichloride, (2) bromodichloroethane, (3) dibromochloroethane, (4) dibromodichloroethane, and (5) tribrormochloroethane.
    Type: Grant
    Filed: September 10, 1998
    Date of Patent: May 22, 2001
    Assignee: Albemarle Corporation
    Inventors: Jon S. Reed, Susan D. Landry, Daniel A. De Schryver, Billie B. Dadgar, Donald E. Balhoff, Charles H. Kolich, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 6232408
    Abstract: Novel brominated styrenic polymers have an ionic bromine content of 2000 ppm or less, and one or more of the following additional characteristics: (a) a TGA temperature for 1% weight loss which is 340° C. or higher, and a chlorine content, if any, of less than about 700 ppm Cl (b) an actual Mw which is within about 20% of the calculated theoretical Mw, the theoretical Mw being based upon the actual bromine content of the brominated styrenic polymer and the Mw of the styrenic polymer reactant used to produce the brominated styrenic polymer; and (c) essentially no content of impurities selected from the group consisting of ethylene dichloride, bromodichloroethane, dibromochloroethane, dibromodichloroethane, and tribromochloroethane. Such flame retardant polymers exhibit superior performance qualities during use, especially in thermoplastics such as glass-filled polyesters and glass-filled nylons.
    Type: Grant
    Filed: September 10, 1998
    Date of Patent: May 15, 2001
    Assignee: Albemarle Corporation
    Inventors: Billie B. Dadgar, Donald E. Balhoff, Charles H. Kolich, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 6232393
    Abstract: Flame retarded thermoplastic polymer compositions are formed by blending together a thermoplastic polymer and at least a flame retardant amount of a brominated styrenic polymer having, prior to blending, a total bromine content of at least about 50 wt % and in addition specified characteristics pertaining to such properties as (i) TGA temperature for 1% weight loss, (ii) hydrolyzable bromine content, (iii) chlorine content (if any), and/or (iv) thermal stability using a described Thermal Stability Test. Blends made with prior art brominated polystyrenes do not possess the enhanced thermal stability and reduced metal corrosiveness provided by these brominated styrenic polymers.
    Type: Grant
    Filed: September 10, 1998
    Date of Patent: May 15, 2001
    Assignee: Albemarle Corporation
    Inventors: Billie B. Dadgar, Donald E. Balhoff, Charles H. Kolich, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 6207765
    Abstract: This invention relates to the bromination of styrenic polymers by contacting same with a brominating agent in the presence of a bromination catalyst and, as a reaction solvent, bromochloro-methane.
    Type: Grant
    Filed: April 13, 1999
    Date of Patent: March 27, 2001
    Assignee: Albemarle Corporation
    Inventors: Meng-Sheng Ao, Billie B. Dadgar, Charles H. Kolich, Donald E. Balhoff, Homer C. Lin, David R. Brackenridge, Thorsten W. Brockman
  • Patent number: 6133381
    Abstract: This invention relates to a thermally stable brominated polystyrene composition which contains alkali metal base (e.g., NaOH) in an amount less than about 1 wt % such that if the flame retardant is dissolved in bromochloromethane and the resultant solution is extracted with water, the resultant water extract exhibits a pH of at least about 9.0. A preferred composition of this type even when heated to 315.degree. C. for one hour did not undergo darkening--the color remained tan. Comparative samples not containing the base turned black under these same conditions. Especially useful compositions additionally have less than 500 ppm, and better still, less than 100 ppm total Cl, and at least about 67 wt % bromine. Processes for producing the compositions are also described.
    Type: Grant
    Filed: April 24, 1998
    Date of Patent: October 17, 2000
    Assignee: Albelmarle Corporation
    Inventors: Jon S. Reed, Charles H. Kolich, Billie B. Dadgar, Donald E. Balhoff, Meng-Sheng Ao, Homer C. Lin, Thorsten W. Brockmann, David R. Brackenridge
  • Patent number: 5965731
    Abstract: In an aqueous reaction medium, phenol is brominated with bromine under conditions forming an aqueous hydrobromic acid phase and an organic phase consisting essentially of molten 2,4,6-tribromophenol. The aqueous hydrobromic acid phase and the molten 2,4,6-tribromophenol are separated from each other, and optionally the molten 2,4,6-tribromophenol is washed with an aqueous decolorizing solution. An alkali metal base and water are mixed with the 2,4,6-tribromophenol to form an alkali metal salt of tribromophenol. Then, in a mixture consisting essentially of water and at least one liquid ketone, cyanuric chloride is reacted with at least a portion of the alkali metal 2,4,6-tribromophenolate of such that tris(2,4,6-tribromophenoxy)-s-1,3,5-triazine is produced.
    Type: Grant
    Filed: September 3, 1998
    Date of Patent: October 12, 1999
    Assignee: Albemarle Corporation
    Inventors: Meng-Sheng Ao, Billie B. Dadgar, Phillip R. Beaver, Mark W. Beltz
  • Patent number: 5916978
    Abstract: This invention relates to the bromination of styrenic polymers by contacting same with a brominating agent in the presence of a bromination catalyst and, as a reaction solvent, bromochloromethane.
    Type: Grant
    Filed: March 13, 1998
    Date of Patent: June 29, 1999
    Assignee: Albemarle Corporation
    Inventors: Meng-Sheng Ao, Billie B. Dadgar, Charles H. Kolich, Donald E. Balhoff, Homer C. Lin, David R. Brackenridge, Thorsten W. Brockmann
  • Patent number: 5852132
    Abstract: This invention features a process for brominating styrenic polymers, which process comprises forming a reaction mass by feeding a mixture, (i) which is substantially free of a bromination catalyst and (ii) which is formed from at least brominating agent and a styrenic polymer, to a catalytic quantity of a bromination catalyst.
    Type: Grant
    Filed: June 11, 1997
    Date of Patent: December 22, 1998
    Assignee: Albemarle Corporation
    Inventors: Billie B. Dadgar, Donald E. Balhoff, Charles H. Kolich, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 5852131
    Abstract: This invention features a process for brominating styrenic polymers which process comprises feeding a first stream comprising a brominating agent, a second stream comprising styrenic polymer and a third stream comprising bromination catalyst to a mixer to intimately mix such streams.
    Type: Grant
    Filed: June 11, 1997
    Date of Patent: December 22, 1998
    Assignee: Albemarle Corporation
    Inventors: Donald E. Balhoff, Billie B. Dadgar, Charles H. Kolich, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 5767203
    Abstract: This invention relates to the bromination of styrenic polymers by contacting same with a brominating agent in the presence of a bromination catalyst and, as a reaction solvent, bromochloromethane.
    Type: Grant
    Filed: April 25, 1997
    Date of Patent: June 16, 1998
    Assignee: Albemarle Corporation
    Inventors: Meng-Sheng Ao, Billie B. Dadgar, Charles H. Kolich, Donald E. Balhoff, Homer C. Lin, David R. Brackenridge, Thorsten W. Brockmann
  • Patent number: 5686538
    Abstract: This invention features a process for brominating styrenic polymers which process comprises feeding a first stream comprising a brominating agent, a second stream comprising styrenic polymer and a third stream comprising bromination catalyst to a mixer to intimately mix such streams.
    Type: Grant
    Filed: September 26, 1996
    Date of Patent: November 11, 1997
    Assignee: Albemarle Corporation
    Inventors: Donald E. Balhoff, Billie B. Dadgar, Charles H. Kolich, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 5677390
    Abstract: This invention features a process for brominating styrenic polymers, which process comprises forming a reaction mass by feeding a mixture, (i) which is substantially free of a bromination catalyst and (ii) which is formed from at least brominating agent and a styrenic polymer, to a catalytic quantity of a bromination catalyst.
    Type: Grant
    Filed: October 26, 1996
    Date of Patent: October 14, 1997
    Assignee: Albemarle Corporation
    Inventors: Billie B. Dadgar, Donald E. Balhoff, Charles H. Kolich, Meng-Sheng Ao, Homer C. Lin
  • Patent number: 4948648
    Abstract: A composite fire resistant laminar cushioning material is disclosed. The material comprises a foamed polyphosphazene upper lamella and a foamed polyurethane lower lamella. The foamed polyphosphazene further comprises a lamelliform substantially unfoamed outer first layer and a substantially foamed second layer. The cushioning material is capable of passing the Cal-133 flammability test.
    Type: Grant
    Filed: December 11, 1989
    Date of Patent: August 14, 1990
    Assignee: Ethyl Corporation
    Inventors: Billie B. Dadgar, Thomas J. Walter