Bayer Aktiengesellschaft

Phenolchemie Gmbh & Co. Kg

Bayer Ag Konzernverwaltung Rp

Tony Van Osselaer

Rainer Neumann

Frieder Heydenreich

Steffen K&uuml;hling

Rolf Lanze

Claus H Wulff

Jurgen Hinz

Kurt-Peter Meurer

Michael Prein

Hermann Kauth

Alfred Eitel

Gottfried Zaby

Werner Verhoeven

Johan Vaes

Hans-Josef Buysch

Klaus Horn

Wilfried Haese

Gerhard Fennhoff

Heiko Herold

Ralf Hufen

Christian Kords

Gerd Fengler

Kaspar Hallenberger

Domien Sluyts

Gabriel Denecker

Rainer Bellinghausen

Otto Schnurr

Hugo Obermann

Thomas Bamberger

Werner Kleinloh

Stefaan De Vos

Ignace Hooftman

Paul Viroux

Gerhard Fennhof

G&uuml;nter Holdenried

Hugo Plompen

Willy Van Herck

Richard Vansant

Roelof Boyens

A method for producing a bisphenol is disclosed. The method entails reacting in at least one first reactant selected from a first group consisting of phenol and substituted phenols with at least one second reactant selected from a second group consisting of ketones and diols, in the presence of hydrogen chloride catalyst and volatile sulphur compound having an SH bond as co-catalyst. The reaction product is a mixture that contains bisphenol, first reactant and second reactant. The catalyst and co-catalyst and water of reaction are separated by distillation. The method is characterized by the high reaction rates and selectivities.

Method for producing bisphenols

A method for producing polycarbonate based on 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethyl cyclohexanone and 4,4-(metaphenylene diisopropyl) diphenol is disclosed. The method is characterized in that the recovery and/or further processing of the polycarbonate is performed at temperatures below 290&deg; C. The polycarbonate thus produced has high purity and high transmission and is suitable for the manufacture of optical data stores.

Polycarbonate substrates

A device for exchanging a die plate of a molten bisphenol A prilling tower is described. The device comprises: (a) at least two die plates; (b) a guide which is in contact with the die plates; and (c) a drive mechanism, wherein the drive mechanism moves the die plates linearly and serially between an operating position and an exchange position along the guide. Also described is a process of automated operation of the device at the top of a bisphenol A prilling tower.

Device for exchanging a die plate of a prilling tower and method for the automatic exchange

A method for producing bisphenol A in prill form is disclosed. Molten bisphenol is top-fed into a prilling tower via a plate containing a plurality of nozzles. A gas coolant guided through a circuit is led into said tower in a counter flow direction. The prills are cooled to about room temperature, collected at the bottom of the tower and removed. Also disclosed is the device for carrying out the inventive method and the prills thus produced.

Method and device for producing bisphenol a prills and bisphenol a prills produced according to this method

A container made of polycarbonate resin is disclosed. The container is characterized in that the polycarbonate is prepared by the phase interface process that is characterized in that the aqueous solution of an alkali salt of a bisphenol used, contains dissolved oxygen in an amount less than 150 ppb. The process for making the container is also disclosed.

Polycarbonate containers

A process of preparing bisphenol A having low residual contents of oxygen and phenol is described. The process involves: (a) melting mixed crystals of bisphenol A and phenol under a nitrogen atmosphere at a temperature of 100&deg; C. to 120&deg; C.; (b) feeding continuously the melt formed in step (a) into the top of a distillation unit under conditions of 120&deg; C. to <160&deg; C. and a pressure of >80 mbar to 200 mbar; (c) feeding contemporaneously with step (b) nitrogen into the bottom of the distillation unit; (d) allowing the melted feed material and the nitrogen feed to contact each other within the distillation unit, thereby forming a concentrated melt material having (i) a phenol content reduced to 10 to 25 wt. %, and (ii) a reduced oxygen content (e.g., an oxygen content of <1 ppm); and (e) optionally passing a stream of nitrogen through the concentrated melt material under conditions of at least atmospheric pressure, 180&deg; C. to 220&deg; C. and a nitrogen partial pressure of 1 to 1.5 bar, thereby removing residual phenol from the concentrated melt material (e.g., resulting in a phenol content of <50 ppm). The melted material having reduced oxygen and phenol contents may be further processed, for example, into pellets.

Method for producing bisphenol-A

A process for the preparation of polycarbonate resins having a low yellowness index is described. The process involves converting phosgene with a sodium bisphenolate solution by means of a phase interface process performed with the exclusion of oxygen. The sodium bisphenolate solution used in the process has a dissolved oxygen content of <150 ppb. Also described are optical data storage media prepared from the polycarbonate of the present invention.

Polycarbonates with a low yellowness index

A process for producing bis(4-hydroxyaryl)alkane is disclosed. The process comprise in sequence the steps of (a) passing inert gas through a melt at 150 to 230&deg; C. that contains bis(4-hydroxyaryl)alkane and other aromatic hydroxy compounds, under conditions designed to remove said other aromatic hydroxy compounds from said melt and to obtain a stream of inert gas that contains said other aromatic hydroxy compounds (b) condensing the stream obtained in (a) to remove said other aromatic hydroxy compound, and to obtain a stream of inert gas, and (c) purifying and compressing the stream of inert gas obtained in (b), and recycling to step (a).

Method for the production of bis(4-hydroxyaryl)alkanes

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

Method for producing dis(4-hydroxyaryl) alkanes

The present invention relates to a process for the continuous production of dihydroxydiphenylalkanes (bisphenols) by the reaction of fresh phenol, and of phenol obtained from the cracking of by-products, with isoalkenylphenol and ketone. In the course of this process, the reaction mixture is worked up by distillation and a high purity bisphenol is produced. The bottom products and distillates containing the by-products are cracked under basic conditions and optionally thereafter under acidic conditions. The cracked products, which substantially consist of isoalkenylphenol and phenol, are recycled, optionally after purification, with the phenol obtained during the purification of bisphenol, to the reaction to form bisphenol, and the residue obtained from cracking is disposed of.

Method for continuous production of dihydroxydiphenylalkanes

The invention relates to a process for the purification of p,p-bisphenolate solutions such as are obtained in the production of bisphenolates from soda lye and bisphenols by extraction.

Purification of p,p-bisphenolate solutions

The transportation and storage of phenol is enhanced by additions of up to 70% by weight of acetone to liquid phenol.

Method for the transport and storage of phenol

The invention relates to a process for drying polymeric powders and polymeric agglomerates, in particular thermoplastic aromatic polycarbonate or other thermoplastic polymers such as, for example, acrylonitrile-butadiene-styrene copolymer, in the melt, whereby thermoplastic polymeric powders or polymeric agglomerates containing water or solvent or both are freed from adhering moisture and contained solvent, accompanied by melting, in an apparatus provided with rotating baffles for cleaning the walls of the apparatus and for distribution and transport of the material being dried, by heat input through the walls or through the rotating baffles or both as well as by heat input as a result of shearing action. The process of drying and that of melting for the subsequent granulation are thereby combined.

Process for drying polymeric powders and polymeric agglomerates

A process for preparing bisphenol A which has a purity of at least 99.95 wt. % of p,p-bisphenol A (BPA). Thermally stable and colour-stable BPA purified in accordance with the invention produces improved thermal and colour stability and improved optical transparency in polymers such as e.g. polycarbonates prepared therefrom.

Process for the purification of bisphenol

The invention relates to the preparation of a transparent crystalline adduct consisting of bisphenol A (75 parts) and bisphenol TMC (25 parts), which has a melting point of 144.degree. C. which is below the melting points of the pure starting compounds bisphenol A (157.degree. C.) and bisphenol TMC (208.degree. C.).

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Krefeld, Germany

Tony Van Osselaer