Patents Represented by Attorney, Agent or Law Firm David E. LaRose
  • Patent number: 5004847
    Abstract: Methods for purifying and agglomerating hexabromocyclododecane particles by heating an admixture formed with wetcake and water.
    Type: Grant
    Filed: December 27, 1989
    Date of Patent: April 2, 1991
    Assignee: Ethyl Corporation
    Inventors: Phillip R. Beaver, Peter M. DiGiacinto, Donald O. Hutchinson, Julio J. Vega
  • Patent number: 5003117
    Abstract: This invention relates to process for preparing decabromodiphenyl methane, which process comprises: charging a reaction vessel with a first portion of a reaction solvent, a catalytic amount of a halogenation catalyst and from about 10 moles to about 30 moles of bromine per mole of diphenyl methane to be reacted; adding a solution of diphenyl methane and a second portion of the reaction solvent to the charged reaction vessel to form a reaction mass, the reaction mass, as it is being formed, being maintained at a temperature within the range of from about -15.degree. C. to about 15.degree. C.; after the diphenyl methane addition is substantially complete, maintaining the temperature of the reaction mass from about 50.degree. C. to about 80.degree. C.; and recovering from the reaction mass decabromodiphenyl methane.
    Type: Grant
    Filed: August 3, 1989
    Date of Patent: March 26, 1991
    Assignee: Ethyl Corporation
    Inventor: Saadat Hussain
  • Patent number: 5000879
    Abstract: This invention relates to a process for increasing the melting point of partially brominated diphenyl oxide mixtures having an average bromine content of 7.2 to 7.7. The process comprises: forming a slurry comprised of C.sub.1 -C.sub.4 alkanol and the mixture; maintaining the slurry until the melting point increase which is sought is obtained; and separating the so-treated mixture from the slurry.
    Type: Grant
    Filed: August 1, 1989
    Date of Patent: March 19, 1991
    Assignee: Ethyl Corporation
    Inventors: Robert M. Moore, Jr., David R. Brackenridge
  • Patent number: 4997953
    Abstract: This invention concerns a process for producing N,N'-bis(tetrabromophthalimide) by: forming a reaction mass from at least (i) tetrabromophthalic anhydride, (ii) hydrazine or a hydrazine provider compound, and (iii) concentrated sulfuric acid; and maintaining the so-formed reaction mass at a temperature within the range of from about 100.degree. C. to about 300.degree. C. for a period up to about 20 hours.
    Type: Grant
    Filed: October 23, 1989
    Date of Patent: March 5, 1991
    Assignee: Ethyl Corporation
    Inventor: Michael G. McKenna
  • Patent number: 4992557
    Abstract: In a first embodiment this invention relates to a process for preparing a white product which principally contains a bisimide. The process comprises: providing tetrabromophthalic anhydride and a solvent in a reaction vessel; forming, at a temperature within the range of from about 140.degree. C. to about 200.degree. C., a reaction mass by adding a diamine, a diamine salt or a mixture thereof to the solution, the formation of the reaction mass resulting in the production of a bisimide precipitate which becomes a component of the reaction mass; terminating the addition of the diamine when the molar ratio of the tetrabromophthalic anhydride initially present in the solution to the diamine or diamine salt added is substantially stoichiometric; cooking the bisimide precipitate to increase the average sphericity of the particles making up the bisimide precipitate; and recovering from the reaction mass, as the bisimide product, the cooked precipitate.
    Type: Grant
    Filed: March 5, 1990
    Date of Patent: February 12, 1991
    Assignee: Ethyl Corporation
    Inventors: Donald O. Hutchinson, Ali M. Dadgar, Keith G. Anderson
  • Patent number: 4990626
    Abstract: In a first embodiment this invention relates to a process for preparing a white product which principally contains a bisimide. The process comprises: providing tetrabromophthalic anhydride and a solvent in a reaction vessel; forming, at a temperature within the range of from about 140.degree. C. to about 200.degree. C., a reaction mass by adding a diamine, a diamine salt or a mixture thereof to the solution, the formation of the reaction mass resulting in the production of a bisimide precipitate which becomes a component of the reaction mass; terminating the addition of the diamine when the molar ratio of the tetrabromophthalic anhydride initially present in the solution to the diamine or diamine salt added is substantially stoichiometric; cooking the bisimide precipitate to increase the average sphericity of the particles making up the bisimide precipitate; and recovering from the reaction mass, as the bisimide product, the cooked precipitate.
    Type: Grant
    Filed: April 4, 1989
    Date of Patent: February 5, 1991
    Assignee: Ethyl Corporation
    Inventors: Donald O. Hutchinson, Ali M. Dadgar, Keith G. Anderson
  • Patent number: 4981890
    Abstract: Described are themoplastic condensation polymers containing a polyhaloaromatic aromatic flame retardant and an aromatic bis-sulfonamide having at least two aromatic rings and from 14 to 30 carbon atoms melt flow improver. These sulfonamides are of advantage in that they have relatively low volatilities at polymer processing temperatures.
    Type: Grant
    Filed: May 23, 1989
    Date of Patent: January 1, 1991
    Assignee: Ethyl Corporation
    Inventor: Robert A. Schleifstein
  • Patent number: 4970891
    Abstract: The apparatus of this invention provides an improved thermal conductivity detector for determination of low levels of gaseous impurities vaporized from solid samples. In particular, a hydrogen impurity vaporized from solid polysilicon beads can be determined down to a detectable limit of about 0.1 ppm by weight. The improvement is comprised of a syringe injection pump for calibration of the instrument, a computer for controlling the syringe infusion pump and for calculating the analytical results, and means for controlling pressure and mass flows of the gas streams.
    Type: Grant
    Filed: December 26, 1989
    Date of Patent: November 20, 1990
    Assignee: Ethyl Corporation
    Inventors: Donald R. Blevins, Gottlieb C. Gaeke, Jr., Doni G. Grande, Robert N. Sanders
  • Patent number: 4963606
    Abstract: This invention relates to a styrenic polymer-based thermoplastic formulation containing a brominated cycloaliphatic flame retardant and a thermal stabilizer system comprising an organotin stabilizer, a hindered phenolic antioxidant and, optionally, a polyhydroxy aliphatic compound.
    Type: Grant
    Filed: September 6, 1989
    Date of Patent: October 16, 1990
    Assignee: Ethyl Corporation
    Inventor: Robert A. Schleifstein
  • Patent number: 4960962
    Abstract: ar-Bromoaromatics having an alkenyl side chain on the aromatic nucleus are formed by feeding a beta-bromoalkyl-ar-bromoaromatic compound, together with a substantial excess of water, into a thermal dehydrobromination zone held at or above 475.degree. C., and maintaining a very short residence time (5 seconds or less) in the dehydrobromination zone. Very little extraneous co-products are formed. For example dibromostyrene was produced by co-feeding bromoethyldibromobenzene (BEDB) and excess amounts of water (using nitrogen as a carrier gas) into a Vycor tube packed with glass beads at 500.degree. C. By suitable controlling residence times, the amount of undesired coproducts formed was kept below 1.5 G. C. area %, and the percentage of BEDB conversion was in the range of 84.1% up to 99.1%.
    Type: Grant
    Filed: July 19, 1989
    Date of Patent: October 2, 1990
    Assignee: Ethyl Corporation
    Inventor: David R. Brackenridge
  • Patent number: 4959500
    Abstract: Described are polybromoaromatic bis-sulfonamides containing at least two bromoaromatic groups, from 18 to 30 carbon atoms (preferably 18 to 24), and from 6 to 14 bromine atoms substituted on the aromatic rings. Such polybromoaromatic bis-sulfonamides may be represented by the general formula ##STR1## where Ar are the same or different polybromoaromatic groups, R is a divalent aromatic or bromoaromatic group, and R' and R" are independently hydrogen atoms, hydrocarbon groups or halohydrocarbon groups in which the halogen atoms are chlorine or bromine, the total number of bromine atoms substituted on the aromatic rings of the groups designated as Ar and R falling in the range of 6 to 14. These sulfonamides are useful as flame retardants and plasticizers for thermoplastic polymers and have the advantage of relatively low volatilities at polymer processing temperatures.
    Type: Grant
    Filed: May 23, 1989
    Date of Patent: September 25, 1990
    Assignee: Ethyl Corporation
    Inventor: Robert A. Schleifstein
  • Patent number: 4957957
    Abstract: Described are thermoplastic polymer compositions (e.g., nylon) containing a polyhaloaromatic sulfonamide in quantity sufficient to improve the melt flow properties of the polymer. Such sulfonamides contain (a) from 7 to 30 carbon atoms, (b) from 2 to 12 chlorine and/or bromine atoms, (c) one nitrogen atom, (d) an aromatic group, bonded to the sulfur atom, in which at least two chlorine or at least two bromine atoms or at least one chlorine atom and at least one bromine atom are directly bonded to the aromatic ring system, and (e) one or two aliphatic, cycloaliphatic, or aromatic organic groups bonded to the nitrogen atom, one such organic group, when an aromatic group, optionally being substituted by one or more bromine and/or chlorine atoms. These sulfonamides are of advantage in that they have relatively low volatilities and good thermal stability at polymer processing temperatures and serve as flame retardants therein.
    Type: Grant
    Filed: June 1, 1989
    Date of Patent: September 18, 1990
    Assignee: Ethyl Corporation
    Inventors: Robert A. Schleifstein, David S. Pietrewicz
  • Patent number: 4957958
    Abstract: Described are thermoplastic polymers (e.g., nylon) containing an aromatic bis-sulfonamide having at least two aromatic rings and from 14 to 30 carbon atoms in the molecule in quantity sufficient to improve the melt flow properties of the polymer. These sulfonamides are of advantage in that they have relatively low volatilities at polymer processing temperatures.
    Type: Grant
    Filed: May 23, 1989
    Date of Patent: September 18, 1990
    Assignee: Ethyl Corporation
    Inventor: Robert A. Schleifstein