Bayer Materialscience Ag

Covestro Deutschland Ag

Bayer Intellectual Property Gmbh

Covestro Intellectual Property Gmbh & Co. Kg

Ulrich Blaschke

Alexander Meyer

Stefan Westernacher

Claus Rüdiger

Christian Münnich

Peter Schwarz

Michael Prein

Rafael Oser

Michael Wagner

Raymond Audenaert

Berit Krauter

Michael Roppel

Rolf Wehrmann

Friedrich-Karl Bruder

Helmut-Werner Heuer

Wilfried Haese

Michael Erkelenz

Hans-Jürgen Thiem

Joerg Reichenauer

Heinrich Hähnsen

Franky Bruynseels

Arne Braun

Raymond Wong

Ice Zhang

Klaus Kraner

Jörg Reichenauer

Rob Eek

Jörg Wehrle

Jesko Zank

Gert Tytgat

Ernst-Joachim Alps

Oser Rafael

The invention relates to opaque colored multilayer articles having a substrate layer based on polycarbonate or polymethylmethacrylate. The compositions of the substrate layer contain a titanium dioxide having particular properties as white pigment. Compared to the Kronos® 2230 white pigment which is conventionally used as white pigment for corresponding compositions and has more particularly been specially matched to polycarbonate, it is possible to achieve considerably higher weathering stability of the colored shaped bodies provided that a UV absorber-containing coating has been applied to the substrate layer. Color stability and gloss are maintained even after weathering, and brilliant colors can thus be assured.

Opaque multi-layer body made of polycarbonate and having weathering stability

The invention relates to the use of branched aliphatic hydrocarbons such as squalane in compositions based on thermoplastic polymer, in particular on polycarbonate, which are used for producing molded parts used in LED lighting units, such as covers for instance. According to the invention it has been found that the use of branched aliphatic hydrocarbons makes it possible to enhance the total transmission and the transmission in the range from 360 to 460 nm, thus making corresponding compositions particularly suitable for producing molded parts for use in combination with white LED light sources. It has additionally been shown that yellowing and haze are simultaneously reduced.

Covers for LED light sources

The present invention relates to compositions containing flame retardant polycarbonate, which are suitable for producing flame-resistant milk-white colored plates. The composition contains polycarbonate, 0.10 to 4.00 weight percent of an acrylate-based scattering additive, 0.50 to 5.00 weight percent of an aromatic-aliphatic polyester, and 0.50 to 8.00 weight percent of a phosphorus-based flame retardant.

Polycarbonate composition having improved flame resistance for extrusion applications

A sheet containing a base layer containing polycarbonate and a flame retardant,  

Polycarbonate plates with improved flame resistance

The present invention relates to a polymer composition containing polycarbonate with a weight-average molecular weight Mw of from 24,000 to 33,000 and 5.0 wt. % to 20.0 wt. % (based on the total amount of the composition) of glass hollow spheres with an alkalinity of less than 1.0 meq/g. The present invention furthermore provides coextruded sheets in which the coextruded layer contains this polymer composition, and shaped articles produced therefrom, in particular containers and pieces of luggage, very particularly suitcases. Sheets which are obtainable with the polymer composition according to the invention have a high mechanical stability, a high scratch resistance, pleasant haptic properties and an excellent homogeneous external visual impression. The present invention furthermore relates to a process for the preparation of these polymer compositions and a process for production of the sheets according to the invention.

Polymer composition having a filler content and coextruded sheet obtainable therefrom

Disclosed is a composition comprising polycarbonate and from 0.0001 weight % to 0.1000 weight % of 2-(2,4-dihydroxy)phenyl-4,6-di(4-phenyl)phenyl-1,3,5-triazine.

Polycarbonate compositions with phenolically substituted triazine derivative

This invention relates to the use of polycarbonate for the production of an optical recording medium in which secure high speed operation, a transcriptability of the pit/groove structure of &#x3e;85% and sufficient disc flatness can be achieved and the polycarbonate is based on bisphenol A and the polycarbonate contains a release agent in an amount less than 2000 ppm.

Substrate material for high speed optical discs

The invention relates to a method for regenerating acidic cation exchangers, which are used as catalysts in the reaction of phenols with aldehydes or ketones to give bisphenols, in particular to give bisphenol A, with acids, with the proviso that, in the method according to the invention, these cation exchangers experience very little mechanical damage due to swelling processes during the regeneration process.

Regeneration of acidic ion exchangers

A process for the storage or transportation of pretreated, conditioned ion exchangers as catalysts for chemical reactions is disclosed. The preconditioned ion-exchange resin is kept as preconditioned ion-exchange resin suspension in a storage or transporting container. The container with the preconditioned ion-exchange resin suspension is transported to either a storage site for storage or to a reactor for transfer of the resin to the reactor.

Method for decanting preconditioned ion-exchange resin suspensions

Processes for producing bisphenols (e.g., bisphenol A (BPA)) having a purity greater than 99.7% are described, such processes including reacting a phenol and acetone in the presence of an acidic catalyst to form a product mixture comprising a bisphenol; removing at least a portion of the bisphenol from the product mixture in the form of a bisphenol/phenol adduct by crystallization, filtration and washing to provide bisphenol/phenol adduct crystals; and removing at least a portion of the phenol from the bisphenol/phenol adduct crystals to provide the bisphenol having a purity of more than 99.7%; wherein the crystallization comprises continuous suspension crystallization and is carried out in at least three crystallization devices arranged such that the product mixture is first cooled in a first stage of the crystallization to a temperature of 50 to 70&#xb0; C. in a first crystallization device and a second crystallization device connected in parallel, and subsequently cooled in a second stage of the crystallization to a temperature of 40 to 50&#xb0; C. in a third crystallization device connected downstream in series to the first and second crystallization devices, and wherein a total dwell time of the product mixture in the crystallization is more than 4 hours.

Crystallization processes for producing bisphenols

A process for the preparation of high purity bisphenol A is disclosed. The multi-step process entails a process whereby bisphenol A of a purity of preferably at least 99.8% can be obtained.

Process for the preparation of high-purity bisphenol A

A branched polycarbonate and processes for its preparation are disclosed. The polycarbonate contains structural units conforming to in which R, R, Rand Rmutually independently denote C-Calkyl, R, Rand Rmutually independently denote hydrogen or C-Calkyl, or Rand R, and Rand R, with the carbon atom to which they are attached, form a C-Ccycloalkyl group, wherein the cycloalkyl group may be substituted.

Branched polycarbonates

A process for the production of bisphenol-A having low concentration of sulphur is disclosed. The process comprise a) reacting phenol with acetone in the presence of a sulfonic acid ion exchanger to form a product mixture containing water, bisphenol-A/phenol adduct, phenol and sulfurous particles, and b) filtering the product mixture to separate the sulfurous particles to obtain a purified product mixture that contains water, phenol and bisphenol-A/phenol adduct. In one embodiment of the process further comprise distilling the purified product mixture to remove the water to obtain a first material system that contains said adduct and phenol, crystallizing the adduct, and removing the phenol by filtration using a filtering apparatus to obtain crystalline adduct. In a yet additional embodiment the process comprise crystallizing the purified product mixture to obtain a second material system that contains crystalline adduct, water and phenol and removing the phenol and water by filtration using a filtering apparatus to obtain crystalline adduct.

Production of bisphenol-A with reduced sulfur content

A process for producing bisphenol A is disclosed. The process entails a) reacting phenol with acetone in the presence of an acidic catalyst to form a reaction mixture that includes bisphenol A and water, and b) removing water from the reaction mixture by distillation in a column to obtain a bottom product, and c) separating bisphenol-A/phenol adduct from the reaction mixture by crystallization and filtration. The bottom temperature of the column is 100 to 150&#xb0; C., the overhead temperature of the column is 20 to 80&#xb0; C., the absolute pressure is 50 to 300 mbar at the head of the column and 100 to 300 mbar at the bottom of the column, and wherein said (c) is carried out before or after said (b).

Dewatering of circulatory flows in the production of bisphenol A

A process for extracting phenol from a phenol-containing aqueous solution is disclosed. The process entails contacting the aqueous solution with an extracting agent that comprise a mixture of 60 to 99% of methyl isobutyl ketone, 1 to 40% of anisole and 0 to 20% of mesitylene.

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Krefeld, Germany

Ulrich Blaschke