Abstract: The invention relates to a process for preparing bromine-containing polymer, comprising a Friedel-Crafts alkylation reaction of tetrabromoxylylene dihalide, or tetrabromoxylylene dihalide in combination with pentabromobenzyl halide, with a reactant having one or more six-membered aromatic rings, wherein the reaction takes place in a solvent in the presence of a Friedel-Crafts catalyst, and isolating from the reaction mixture the bromine-containing polymer. The so-formed polymers and their use as flame retardants form additional aspects of the invention.

Abstract: A transparent composition comprising polycarbonate and a mixture of flame retardants, wherein the flame retardants are aryl phosphate ester of hydroquinone and tris(2,4,6-tribromophenoxy)-s-triazine.

Abstract: The invention provides a process for preparing bromine-containing polymers, comprising a Friedel-Crafts alkylation reaction of pentabromobenzyl halide with a polymer reactant which contains one or more six-membered aromatic ring(s) in its repeat unit, in the presence of at least one Friedel-Crafts catalyst. The so-formed bromine-containing polymers, having pendent —CH2C6Br5 groups attached to at least a portion of the six-membered aromatic rings of the polymer, with a carbon ring atom of said six-membered aromatic ring being bonded to the aliphatic carbon of said —CH2C6Br5 pendent group, are also provided. These bromine-containing polymers are useful as flame retarding agents.

Abstract: The invention relates to compounds of the formula Ar(—CH2C6Br5)y, wherein Ar indicates a structure comprising one or more six-membered aromatic ring(s) and —CH2C6Br5 indicates a pentabromobenzyl group, characterized in that at least one carbon atom of said six-membered aromatic ring(s) is bonded to the benzylic carbon of said —CH2C6Br5 group, wherein y, which indicates the number of the —CH2C6Br5 groups in said compound, is not less than 1. Processes for preparing the compounds and their use as flame retardants are also disclosed.

Abstract: The invention relates to a process for recovering bromide from a halide-containing aqueous stream, comprising the steps of: providing a feed of halide-containing aqueous stream; contacting an anion-exchange resin with said feed, to form halide-loaded resin; treating said halide-loaded resin with a regenerant and subsequently with a rinse to produce, in succession, a chloride-rich solution, a mixed chloride/bromide solution, a bromide-rich solution and an essentially halide-free solution; directing said mixed chloride/bromide solution to said feed; processing said bromide-rich solution to recover one or more bromide products; and utilizing said essentially halide-free solution for regenerant dilution and/or rinsing of said resin. An apparatus for carrying out the process is also disclosed.

Abstract: The invention relates to the use of 1-alkyl-2-alkyl pyridinium halide (e.g., 1-ethyl-2-methyl pyridinium bromide), 1-alkyl-3-alkyl pyridinium halide (e.g., 1-ethyl-3-methyl pyridinium bromide) or 1-alkyl-3-alkyl imidazolium halide (e.g., 1-butyl 3-methyl imidazolium bromide) as additives in an electrolyte used in hydrogen/bromine cells, for complexing the elemental bromine formed in such cells. The invention also provides an electrolyte comprising aqueous hydrogen bromide and said additives, and processes for operating an electrochemical flow cell selected from the group consisting of hydrogen/bromine or vanadium/bromine cells.

Abstract: A solvent extraction process for recovering bromide from a sulfate-containing aqueous stream, the process comprises an extraction step wherein said aqueous stream is mixed with an extraction medium comprising a tertiary amine extractant dissolved in one or more water-immiscible organic solvents, wherein said mixing is carried out in a strongly acidic environment, thereby forming bromide-containing extract and a raffinate with a reduced bromide level, wherein the bromide-containing extract is optionally treated to further minimize the presence of sulfate and is subsequently combined with an aqueous calcium source to form calcium bromide.

Abstract: The invention relates to the use of at least one 1-alkyl-3-alkyl-pyridinium halide, in particular 1-alkyl-3-methyl-pyridinium bromide, as an additive in bromine-generating electrochemical cells, such as zinc/bromine cells. Processes for preparing 1-alkyl-3-methyl-pyridinium bromide and concentrated aqueous solutions comprising same for use as additives in the aforementioned cells, are also disclosed.

Abstract: The invention relates to the use of nitrogen-containing compounds belonging to the classes of N-alkyl pyridinium halide, N-alkyl-2-alkyl pyridinium halide and 1-alkyl-3-alkyl imidazolium halide, as additives in electrolyte solutions for zinc bromine membraneless flow cells. The invention also provides electrolyte solutions comprising such additives and processes for operating said cells.

Abstract: The invention relates to a process for preparing bromine-containing polymer, comprising a Friedel-Crafts alkylation reaction of tetrabromoxylylene dihalide, or tetrabromoxylylene dihalide in combination with pentabromobenzyl halide, with a reactant having one or more six-membered aromatic rings, wherein the reaction takes place in a solvent in the presence of a Friedel-Crafts catalyst, and isolating from the reaction mixture the bromine-containing polymer. The so-formed polymers and their use as flame retardants form additional aspects of the invention.

Abstract: A liquid flame retardant composition which comprises one or more flame retarding agents, which are the epoxides obtainable by reacting tetrabromobisphenol A with epichlorohydrin and their end-capped derivatives represented by Formula (1) is provided. The liquid composition is especially useful in the preparation of rigid polyurethane foams.

Abstract: A process for preparing pentabromobenzyl acrylate through the reaction of pentahalobenzyl halide with a salt of acrylic acid in a water-immiscible solvent, wherein said salt is in aqueous form and the reaction is carried out in the presence of a phase transfer catalyst. A process for polymerizing the pentabromobenzyl acrylate in halogenated aromatic solvent and the poly(pentabromobenzyl acrylate) obtained are also disclosed.

Abstract: Poly (pentabromobenzyl acrylate) having weight average molecular weight (Mw) in the range from 4,000 to 120,000 and polydispersity index of less than 10 as determined by high temperature gel permeation chromatography, wherein the glass transition temperature of the poly (pentabromobenzyl acrylate) is not more than 150 C.°, the poly (pentabromobenzyl acrylate) includes chains which are terminated by an end group derived from a chain length regulator, wherein the end group is a thiol group —SR1, and wherein R1, is a linear or branched alkyl group composed of not less than 8 carbon atom.

Abstract: A flame retardant composition for flammable plastic materials and a method for producing the same are disclosed. The flame retardant composition comprises 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine that contains 1 to 1000 ppm of a metal species of a water-insoluble polyvalent metal compound selected from the group consisting of oxide, hydroxide, carbonate, phosphate, sulfate and silicate present in the particles of 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine. The flame retardant composition is produced by reacting an alkali metal salt of 2,4,6-tribromophenol and cyanuric chloride in the presence of said water-insoluble polyvalent metal compound.

Abstract: The invention relates to compounds of the formula Ar(—CH2C6Br5)y, wherein Ar indicates a structure comprising one or more six-membered aromatic ring(s) and —CH2C6Br5 indicates a pentabromobenzyl group, characterized in that at least one carbon atom of said six-membered aromatic ring(s) is bonded to the benzylic carbon of said —CH2C6Br5 group, wherein y, which indicates the number of the —CH2C6Br5 groups in said compound, is not less than 1. Processes for preparing the compounds and their use as flame retardants are also disclosed.

Abstract: A flame retardant composition for flammable plastic materials and a method for producing the same are disclosed. The flame retardant composition comprises 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine that contains 1 to 1000 ppm of a metal species of a water-insoluble polyvalent metal compound selected from the group consisting of oxide, hydroxide, carbonate, phosphate, sulfate and silicate present in the particles of 2,4,6-tris(2,4,6-tribromophenoxy)-1,3,5-triazine. The flame retardant composition is produced by reacting an alkali metal salt of 2,4,6-tribromophenol and cyanuric chloride in the presence of said water-insoluble polyvalent metal compound.

Abstract: The invention relates to the free radical polymerization of tetrahalogen xylylene diacrylates monomers, either in a mixture of water-miscible aprotic solvent and water, or in a water-immiscible solvent, in the presence of a chain length modifier.

Abstract: A process for preparing an aqueous solution of N-ethyl-2-methylpyridinium bromide (2-MEPy), comprising reacting 2-picoline and ethyl bromide in a pressure reactor at a temperature above the melting point of the reaction mixture, combining the reaction product with water, wherein said reaction product consists essentially of 2-MEPy in a liquid form, and recovering an aqueous solution of 2-MEPy.

Abstract: An aqueous biocidal composition comprising a mixture of hydrochloric acid (HCl), urea, and sodium hypochlorite (NaOCl) at acidic pH, a method for manufacturing the composition and a biocidal technology for treating industrial water.

Abstract: This invention provides granulated methylene dithiocyanate for safe and environmentally friendly industrial antimicrobial use, and a process for manufacturing it.