Bayer Aktiengesellschaft

Bayer Materialscience Ag

Frx Polymers, Inc.

Michael Prein

Rainer Neumann

Frieder Heydenreich

Rolf Lanze

Michael B&ouml;diger

Uwe Hucks

Steffen K&uuml;hling

Stephan Konrad

Pieter Ooms

Johann Rechner

Helmut-Werner Heuer

Wilfried Haese

Gerhard Fennhoff

Dieter Freitag

Hermann Kauth

Georg Ronge

Silke Kratschmer

Lawino Kagumba

Ulrich Blaschke

Tony Van Osselaer

Pin Go

Raymond Audenaert

Christian Münnich

Michael Bödiger

Lutz Gottschalk

Berit Krauter

Rob Eek

Wolfgang Ebert

Alexander Meyer

Klaus Horn

Reinhold M Klipper

Ralf Hufen

Christian Kords

Kaspar Hallenberger

Christine Mendoza-Frohn

Rolf Bachmann

Ulrich Schnegg

Claus Rüdiger

Domien Sluyts

Rudolf Wagner

Werner Verhoeven

Martin D&ouml;bler

Jürgen Röhner

Uli Franz

Johan Vaes

Marco Roelofs

Axel Brenner

Wolfgang Wambach

Tanja Grüter-Reetz

Helmut Einberger

Dirk M&uuml;ller

Gerald John

Edmund Dikow

Nikolai Kostyszyn

Johannes-Peter Sch&auml;fer

Hans-Ludwig Fofonka

Gert Tytgat

Disclosed are random copoly(phosphonate carbonate)s with the high molecular weight and narrow molecular weight distribution exhibiting a superior combination of properties compared to prior art.

High molecular weight, random, bisphenol based copoly(phosphonate carbonate)s

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

The present invention provides a polycarbonate resin produced by the continuous interfacial process characterized in that after alkaline hydrolysis with sodium hydroxide, the polycarbonate resin contains an amount of 0.01 to 150 ppm of carbamate compounds according to formula (1) said amount measured by high pressure liquid chromatography, wherein Rand Rindependently of one another denote hydrogen or C-C-alkyl, or together denote C-C-alkylidene, and Rand Rindependently of one another denote hydrogen. C-C-alkyl or phenyl, or together with the carbon atom to which they are bonded form cyclohexyl or trimethylcyclohexyl, the process comprising phosgene reacting with at least one bisphenol at 8 to 17% molar excess of phosgene relative to the bisphenol.

Polycarbonates with good wettability

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

The present invention relates to a solid sheet prepared from a composition that includes: (a) a transparent polycarbonate; and (b) transparent polymeric particles having an optical density which differs from the transparent polycarbonate matrix material. The present invention also relates to use of such a solid sheet as a diffuser sheet in flat screens.

Light-scattering shaped articles of high light transmission and the use thereof in flat screens

A continuous process for the separation of phenol is disclosed. The process includes (a) feeding a stream of material, produced while preparing bisphenol A by reacting phenol with acetone, into a distillation column containing at least 5 theoretical separation stages, b) distilling-off the phenol as a top product and discharging from the column a bottom product containing secondary components, c) continuously introducing a portion of the bottom product into a dwell-time container operating at process parameters sufficient to cause, in the presence of an acidic catalyst, at least partial isomerization of the secondary components to form an isomerized product and d) introducing the isomerized product to the distillation column. The introducing of the bottom product is at a rate that is more than 30% of the rate of feeding of the stream at temperatures greater than 190&#xb0; C. and hydrodynamic dwell time of at least 120 minutes.

Process for the separation of phenol from phenol-containing streams from the preparation of Bisphenol A

The invention relates to a method for producing polycarbonate according to the method for the transesterification of molten mass whereby bis-(hydroxyaryl) compounds (bisphenols) and diaryl carbonates are reacted by means of reactive rectification.

Reactive rectification

The present application relates to a process for producing high-purity bis(4-hydroxyaryl)alkanes from adducts of bis(4-hydroxyaryl)alkanes and aromatic hydroxy compounds, which are obtained by acid-catalysed reaction of the aromatic hydroxy compounds with ketones.

Bis(4-hydroxyaryl)alkanes

The application relates to a process for producing high-purity bis(4-hydroxyaryl)alkanes from adducts of bis(4-hydroxyaryl)alkanes and aromatic hydroxy compounds, which are obtained by acid-catalysed reaction of the aromatic hydroxy compounds with ketones.

Bisphenol phenol adducts

The invention relates to a continuous method for producing polycarbonates by transesterifying diaryl carbonates with dihydroxyaryl compounds in the presence of quaternary onium compounds. The invention also relates to polycarbonates produced thereby and products produced from said polycarbonates.

Method for producing polycarbonates

The present invention provides crystals of an adduct of a bisphenol and a phenol and methods of producing those crystals. The crystals may find use in preparing bisphenols.

Method for producing bisphenols

The present invention provides mixtures containing bisphenol A, methods for the production thereof. The mixtures of the present invention may find use in the production of polymeric materials.

Substance mixture containing bisphenol A

A process for the production of 2,2-bis(4-hydroxyphenyl)propane (BPA) is disclosed. The process that entails reacting acetone with phenol in the presence of cross-linked sulfonated polystyrene resins is characterised in that BPA is separated from the reaction solution downstream of the reaction unit by means of a multi-stage vacuum distillation and a subsequent single- or multi-stage layer crystallisation. The by-product stream with accumulated by-products is returned downstream of the reaction unit.

Bisphenol production

Monodisperse cation-exchangers and anon-exchangers are conditioned by a process and thereafter used as catalysts and for the production of bisphenols.

Method for conditioning ion exchangers

Growing community of inventors

Brasschaat, Belgium

Michael Prein