Bayer Aktiengesellschaft

Karl-Heinrich Meyer

Ludwig Bottenbruch

Willi Dunwald

Bernhard Schulte

Wolfgang Jakob

Franz Alfes

Wolfgang M Eisermann

Manfred Schmidt

Erhard Tresper

Wolfgang Alewelt

Claus Burkhardt

Diez Heine

Rudolf Merten

Uwe Hucks

Hermann Perrey

Ludwig Rottmaier

Martin Ullrich

Jurgen Lewalter

Wolfgang Arlt

Friedrich Kowitz

Kurt Weirauch

Wolfgang Jacob

August Horsthemke

This invention relates to a simplified process for the preparation of polyarylene sulphides with improved product quality from alkali metal sulphides and dihalogenated aromatic compounds, in which the alkali metal sulphides are prepared and reacted in situ.

Process for the preparation of polyarylene sulphides

The isolation of polyarylene sulphides by freeing polyarylene sulphides of the type obtained in customary production processes from adherent water and any other volatile constituents by treating the polyarylene sulphides in screw machines and optionally melting them either simultaneously or subsequently.

Process for the isolation of polyarylene sulphide

The present invention relates to the isolation of thermoplastic polycarbonates from their solutions by treating the organic solutions, obtained in the phase boundary processes, of the thermoplastic polycarbonates with vapors of benzene or alkylbenzenes.

Process for the isolation of thermoplastic polycarbonate from solution

The invention relates to an improved process for isolating pulverulent chlorinated aliphatic polymers from their aliphatic chlorohydrocarbon solutions by introducing a mixture of steam and special solvent into said solutions, removing the aliphatic chlorohydrocarbon by steam distillation, and isolating the chlorinated polymer in the customary manner as a solid. The process produces a product which is practically free (.ltoreq.20 ppm) of toxic aliphatic chlorohydrocarbons and can be safely used in paints, adhesives or printing inks.

Process for isolating pulverulent chlorinated aliphatic polymers from

A process for the production of 2-aryl-4-acyl-1.3.4-oxdiazolones-(5), in which an aromatic carboxylic acid hydrazide is reacted at a pH value of from 1.8 to 3.0 with phosgene in a mixture consisting of water and acetone at a temperature of from 0.degree. C. to 50.degree. C., subsequently the pH is increased to from 9.5 to 11.0, then about 100 mol % of a carboxylic acid chloride or about 50 mol % of a dicarboxylic acid chloride (based on mols of carboxylic acid hydrazide) is added and optionally from 10.sup.-4 to 1.0 mol % (based on mols of carboxylic acid hydrazide) of a tertiary amine or phosphine is added as a catalyst and the reaction is completed at a temperature from 0.degree. C. to 50.degree. C.

Process for the production of 2-aryl-4-acyl-1.3.4-oxdiazolones-(5)

This invention relates to a process for the production of compounds containing at least one (thio)-hydantoin ring in the molecule by reacting a carbodiimide with hydroxy- or mercapto-succinic acid diesters corresponding to the following general formula: ##STR1## wherein R.sup.4 and X are as defined in the description.

Process for the production of (thio) hydantoins

The invention relates to a process for the production of compounds containing at least one hydantoin ring by reacting a carbodiimide with derivatives of succinic acid anhydride corresponding to the following general formula: ##STR1## wherein R.sup.4 represents a halogen atom, an alkyl-carboxy or aryl-carboxy group; or with maleic acid anhydride in the presence of aromatic OH-functional compounds at temperatures of from about 20.degree. to about 250.degree. C., optionally in a solvent and optionally in the presence of a catalyst, and also to the use of the polyhydantoins obtained, where they have high molecular weights, as high temperature-resistant coating compositions, films, powders, adhesives, lacquers or mouldings.

Process for the production of hydantoins

The invention relates to a process for the production of a chlorinated polymer having a chlorine content of from 30 to 70% by weight, which comprises chlorinating a polymer in a chlorinated hydrocarbon solvent, removing the solvent using steam and/or hot water in the presence of at least 1% by weight, based on the chlorinated polymer, of an alkoxylation product of 1 mole of a primary aliphatic alcohol containing at least 8 carbon atoms and at least 1.5 moles of propylene oxide and drying the precipitated chlorinated polymer.

Process for the production of water-resistant, film-forming chlorinated

A process for the preparation of bisphenols, which comprises condensing an aliphatic or cycloaliphatic ketone with a phenol having a free p-position in the presence, as a condensing agent, of from 0.3 to 3 mols, per mol of ketone, of an aromatic sulphonic acid of the formula (III) or (IV): ##STR1## wherein R.sup.3 is an inert organic radical,

Process for the preparation of pure 4,4'-dihydroxyphenyl alkanes or

In non-phenolic solvents soluble Polyamid-hydantoins optionally containing ester and/or imide and/or isocyanurate groups are obtained by reacting polyisocyanates with polyfunctional amino carboxylic acid derivatives and a compound containing at least a carboxylic group preferably in the presence of a non-phenolic solvent.

Coating compositions obtained by reacting amino carboxylic acids

Polymers comprising terephthalyl-or oxal arylamide groups represent excellent light stabilizers for synthetic, semi-synthetic and/or naturally occurring organic materials.

Polyarylamide, their production and their use as absorbers for

Moulding compositions for the production of mouldings with fire-retarding properties and with a polytriazine structure, comprising mixtures of (A) 10 to 90% by weight of at least one polyfunctional, aromatic halogen-free cyanic acid ester or a prepolymer thereof which is still fusible or soluble in solvents, and (B) 10 to 90% by weight of at least one polyfunctional, aromatic halogen-containing cyanic acid ester or a prepolymer thereof which is still fusible or soluble in solvents.

Moulding compositions of mixtures of halogen-containing and halogen-free

Aromatic cyanic acid esters are obtained by an improved process. Optionally substituted mononuclear phenols or polynuclear phenols optionally interrupted through bridge members such as ##EQU1## and/or divalent hydrocarbon bridges are condensated in form of an aqueous phenolate solution with cyanogen halide dissolved in organic solvents in the presence of catalytic quantities of a tertiary amine in a highly disperse system (two phase boundary reaction). The cyanic acid esters obtained are highly pure and stable.

Production of aromatic cyanic acid esters

A process for the production of very pure 2,2-bis-(4-hydroxy-3,5-dichlorophenyl)-propane (TCB), wherein a solution of TCB in an aromatic hydrocarbon is treated with hot water, followed by crystallization of TCB from the aqueous solution by addition of a halogenated aliphatic hydrocarbon.

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Krefeld, Germany

Karl-Heinrich Meyer