In an embodiment, a continuous method of forming a bisphenol A oil comprises forming the bisphenol A oil by mixing a molten bisphenol A and water; wherein the bisphenol A oil comprises 10 to 30 wt % water based on a total weight of the bisphenol A oil and is at a temperature of 100 to 140 C.; flowing at least a portion of the bisphenol A oil through an inline densitometer and measuring a real-time density and a real-time temperature of the bisphenol A oil; determining a real-time concentration of the bisphenol A oil based on said real-time density and said real-time temperature.

Polycarbonate polyols are made by copolymerizing carbon dioxide and an alkylene oxide in the presence of a starter compound and a carbonate catalyst. The process is operated in semi-batch mode by combining starter, catalyst and a small amount of alkylene oxide in a reaction vessel, pressurizing the vessel with carbon dioxide, initiating polymerization, and then feeding both carbon dioxide and alkylene oxide to the vessel under polymerization conditions without removal of product until the feeds are completed.

The invention relates to polycarbonates with extremely low residual levels of volatile constituents and thermal degradation products, and also improved optical properties, especially Yellowness Index (YI) and good thermal stability, from solvent-containing polymer melts. The invention further relates to an apparatus and a process for preparing these polycarbonates with the aid of a devolatilizing extruder with at least three devolatilizing zones, and zones for introducing entraining agent into dispersion are present upstream of at least three devolatilizing zones.

A method of manufacturing a poly(ether-carbonate) polyol comprises a polymerization stage that includes polymerizing carbon dioxide and at least one alkylene oxide, with a starter, in the presence of a double metal cyanide polymerization catalyst and a catalyst promoter that is devoid of halide anions and cyanide. The catalyst promoter is separate from the double metal cyanide polymerization catalyst.

A method for assembling a polycarbonate manufacturing apparatus comprising a plurality of apparatus elements, the method comprising: protecting an opening of each apparatus element, wherein the apparatus element is prepared as follows: at least a portion of a metal surface that comes into contact with an internal fluid of the apparatus element is polished with an abrasive corresponding to buff #400, and the polished metal surface is washed until becoming a state where no dirt is attached to a nonwoven fabric in a test of contact between the metal surface and the nonwoven fabric; and connecting the opening of the apparatus element to the opening of another apparatus element within a dust cover.

A method is described for producing a polycarbonate by reacting one or more diaryl carbonates with one or more aromatic hydroxy compounds, which are first mixed in a mixing device and enter, as a raw material mixture, a raw material mixture container to subsequently react in one or more reactors under reduced pressure and increased temperature to form polycarbonate, wherein the mixture of diaryl carbonate and aromatic hydroxy compound is subjected to a purification by an inert gas in a countercurrent process, in a stripping device, before entering the raw material mixture container. The present invention also relates to a stripping device which is particularly suitable for purifying a raw material mixture stream, and to the use of such a stripping device in a method for producing polycarbonate.

A process, and a device system suitable therefore, for producing polycarbonates are provided. The process contains the steps of producing at least chlorine and hydrogen by the chloralkali electrolysis of alkali chloride, preferably sodium chloride, in aqueous solution; synthesizing phosgene from carbon monoxide and chlorine; reacting phosgene with diol to form polycarbonate; providing a cleaned carbon dioxide gas stream as a process product of a process containing the steps of providing a CO2 gas stream and purifying the carbon dioxide gas stream by removing secondary constituents; converting the purified carbon dioxide into carbon monoxide and hydrogen by means of an RWGS reaction, which carbon monoxide and hydrogen can be used as raw materials for the polycarbonate production.

Provided is an aromatic branched polycarbonate having a predetermined repeat unit in a main chain and a branched chain, and having one or more kinds of predetermined branched structures in the main chain and the branched chain, wherein ratio of a total amount of substance of the branched structures to an amount of substance of the predetermined repeat unit is in a predetermined numeric range; and containing one or more kinds of predetermined oligomers, wherein a total mass of the oligomers is in a predetermined numeric range, and a ratio of an amount of substance of oligomers having a specific structure to a total amount of substance of the oligomers is in a predetermined numeric range.

A reactor for the manufacture of interfacial polycarbonate by reacting phosgene and one or more bisphenols in a liquid phase, the reactor comprising a reactor vessel and reactor internals, wherein at least part of the inner surface of the reactor and/or part of the surface of the reactor internals is manufactured from or cladded with a titanium alloy comprising palladium.

The present invention relates to a method for producing polyether carbonate polyols by addition of one or more alkylene oxides and carbon dioxide to one or more H-functional starter substances in the presence of at least one DMC catalyst, in which the reaction is conducted in a main reactor (8) and a tubular reactor (11, 17) connected as a post reactor downstream thereof, wherein the method is characterized in that at the outlet (13) of the tubular reactor (11, 17) a temperature is set that is at least 10 C. above the temperature in the inside of the main reactor (8). The invention further relates to a device for carrying out said method.