Bayer Aktiengesellschaft

Wolfgang Jakob

Erhard Tresper

Wolfgang Alewelt

Gerhard Fennhoff

Willi Dunwald

Bernhard Schulte

Karl-Heinrich Meyer

Dieter Freitag

Manfred Schmidt

Burkhard Kohler

Hans-Joachim Traenckner

Harald Pielartzik

Manfred Ehlert

William C Bushong

Hans-Josef Buysch

Karl-Heinz Ott

Dieter Wittmann

Thomas Eckel

Ludwig Bottenbruch

Pieter Ooms

Klaus Reinking

Jochen Schoeps

Norbert Schon

Steffen Kuhling

Klaus D Berg

Gottfried Zaby

Ernst-Ulrich Dorf

Wolfgang Russeler

Wolfgang Wehnert

Gabriel Denecker

Franz Alfes

Wolfgang Arlt

Wolfgang M Eisermann

Jurgen Dahmer

Eric Bischof

Wilfried Cramer

Karl-Heinrichrich Meyer

The present invention relates to a process for the continuous production of carbonates having aromatic ester groups by reacting aromatic hydroxy compounds with phosgene in the gas phase in the presence of heterogeneous catalysts.

Process for the continuous production of aryl carbonates

1. Thermoplastic molding compounds containing A. 5 to 95 parts by weight of an aromatic polycarbonate, B. 1 to 50 parts by weight of a vinyl copolymer and C. 5 to 95 parts by weight of one or more graft polymers obtained by graft polymerization, characterized in that 10 to 100% of component A is replaced by a mixture of two polycarbonates A.1 and A.2 of identical structure,

Polycarbonate/ABS molding compounds

A process for the purification of bisphenols by distillation.

Process for the purification of bisphenols

The invention relates to a process for stabilizing the molecular weight of high molecular weight, optionally branched polyarylene sulfides prepared by reaction of aromatic dihalogen compounds and, optionally, aromatic trihalogen or tetrahalogen compounds and, optionally, polymer-chain-terminating monomers with alkali metal sulfides and/or alkali metal hydrogen sulfides at elevated temperature in aprotic polar solvents, characterized in that, after the desired molecular weight has been reached, alkali metal sulfides and/or alkali metal hydrogen sulfides present in excess are at least partly reacted with acids to form the alkali metal salts of the acids and hydrogen sulfide.

Process for stabilizing the molecular weight of linear or optionally

A process for the purification of waste of thermoplastic resins containing at least one member selected from among aromatic polycarbonates, aromatic polyester carbonates and aromatic polyesters and at least one of aluminum, lacquers and dyes which waste accumulates in the production of optical moldings is disclosed. The process which entails size reduction of the waste, chemical wash and filtering steps yields purified resins suitable for thermoplastic processing.

Purification of polycarbonate, polyester carbonate or polyester waste

A process is disclosed for the purification of lacquer-and optionally dye and metal- containing waste of thermoplastic aromatic polycarbonates and/or thermoplastic aromatic polyester carbonates. The waste which result upon the production of moldings, such as audio compact discs, lenses for spectacles or head-lamp reflectors is processed in accordance with the invention to yield useful resin suitable for reprocessing as a molding resin. In accordance with the process, the waste is first size-reduced and then heated with acid to the reflux temperature while stirring. After a water wash there is followed a drying step. In accordance with the process, in instances where the waste does not originally contain metal, the metal in powder form is added before the acid treatment.

Purification of polycarbonate and polyester carbonate waste

The invention relates to mixtures of polyarylene sulphides, maleimides, glass fibres and if appropriate other additives. The mixtures are distinguished by good mechanical properties.

Mixture of polyarylene sulphides, glass fibres and maleimides

The invention relates to mixtures of poly(arylene sulphides), glass fibres and maleamidic acids, which are remarkable for good mechanical properties and an increased melt viscosity of the matrix resin.

Mixtures of poly(arylene sulphides), maleamidic acids and glass fibres

The invention relates to new sulphur-containing copolymers, a process for their preparation from a sulphur source and a mixture of dihalogenoaromatics and dihalogenoaliphatics and their use for the production of shaped articles.

Copoly arylene/alkylene sulfide

This invention relates to a process for the preparation of crystalline polyarylenesulphides. Polyarylenesulphides with a high degree of purity, low electrolyte content and low non-uniformity are obtained. The polyarylenesulphides obtained have improved mechanical and electrical properties.

Isolation of purified solid polyarylene sulfide directly from

This invention relates to a process for the preparation of N-alkylated caprolactams by the cyclization of N-alkylated caproic acids.

Process for the preparation of N-alkylated caprolactams

The invention relates to polyarylene sulphides with melt viscosities settable to defined values. The products are distinguished by high stability of the melt. They are obtained by adding, in the preparation of these polyarylene sulphides, certain phenols as chain terminators to the reaction mixture.

Polyarylene sulphide capped with monophenol compound

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 new process for the production of compounds containing at least one hydantoin ring by reacting a carbodiimide with a derivative of an .alpha.,.beta.-unsaturated carboxylic acid corresponding to the following general formula: ##STR1## wherein R.sup.3, R.sup.4 and R.sup.5 are as defined in the description.

Growing community of inventors

Moers, Germany

Wolfgang Jakob