Abstract: A process for the preparation of carbonates containing aromatic ester groups is disclosed. The process entails reacting aromatic monohydroxy componds with phosgene or with chlorocarbonic acid esters of aromatic monohydroxy compounds at a temperature of 50 to 350° C. and in the presence of active carbon as catalyst.

Abstract: 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.

Abstract: Described herein is a process for the preparation of 1,3-dioxan-2-one group-containing oligourethanes by reacting a) hydroxy-functional 1,3-dioxan-2-ones with b) compounds having an average of at least two isocyanate groups per molecule; the oligourethanes obtainable by this process; and their use, optionally in combination with compounds containing active hydrogen atoms, for the preparation of plastics or as a binder or binder component in coating compositions.

Abstract: Carbonates with aromatic ester groups can be produced by reaction of aromatic monohydroxy compounds with phosgene or with chloroformic acid esters of aromatic monohydroxy compounds, working at a temperature in the range of 50.degree. to 350.degree. C. in presence of oxides of the metals of Group IV B of the Mendeleeff periodic table as heterogeneous catalysts.

Abstract: Organic carbonates which contain at least one aromatic ester group can be obtained continuously from carbonates, which contain at least one aliphatic ester group, and a phenolic compound in the presence of a transesterification catalyst known per se in that the reaction is carried out in a bubble column reactor or in a cascade of at least two bubble column reactors in such a way that the phenolic compound is metered into the first bubble column and the carbonate containing at least one aliphatic ester group is metered into each individual bubble column, but preferably only into the last bubble column. The carbonate containing at least one aromatic ester group is taken off in the liquid state from the last bubble column. Volatile reaction products, for example eliminated alcohol or a dialkyl carbonate are taken off at the upper end of each individual bubble column, preferably at the upper end of the first bubble column.

Abstract: This invention provides a process for the purification of diphenyl carbonate (DPC) from crude products of diphenyl carbonate production. In this process, crude products are used that have a distillable fraction consisting of over 70 wt. % diphenyl carbonate and are fractionally crystallised from the melt (fractionating melt crystallisation).

Abstract: Carbonates with aromatic ester groups may be prepared by reacting aromatic monohydroxy compounds with phosgene or with chloroformates of aromatic monohydroxy compounds, wherein the process is performed at a temperature in the range 50.degree.-350.degree. C. in the presence of aluminosilicates as heterogeneous catalysts.

Abstract: Carbonates with aromatic ester groups may be prepared by reacting aromatic monohydroxy compounds with phosgene or with chloroformates of aromatic monohydroxy compounds, wherein reaction takes place at a temperature in the range 50.degree. to 350.degree. C. in the presence of aluminum oxides as heterogeneous catalysts.

Abstract: Organic carbonates containing at least one aromatic ester group can be obtained in a continuous manner from carbonates containing at least one aliphatic ester group and a phenolic compound in the presence of a transesterification catalyst known per se by carrying out the reaction in at least two stirred containers connected one behind the other in such a way that, in each case, the phenolic compound is metered in liquid form into the first stirred container and the carbonate containing at least one aliphatic ester group is metered in liquid form into one or more of the stirred containers. The carbonate containing at least one aromatic ester group is removed in liquid form from the last stirred container. Volatile reaction products, for example alcohol which has been cleaved out or a dialkyl carbonate are removed in gaseous form from one or more stirred containers.

Abstract: A continuous process for splitting an aromatic polycarbonate resin is disclosed. Accordingly there are reacted in a distillation column and in the presence of a catalyst(i) a polycarbonate resin in solution with(ii) methanolto produce a dihydroxy compound and dimethyl carbonate. The solution which contains polycarbonate and monohydroxy compound solvent exclusive of methanol is fed into the upper section of said column and the methanol is fed into the lower section of the column. The methanol is fed in the form of a mixture containing methanol and about 1-50 weight percent of dimethyl carbonate. The dimethyl carbonate thus produced is removed from an upper section of the column and the dihydroxy compound is removed from a lower section of the column.

Abstract: A process is disclosed for cleaving polycarbonates into bisphenols and diaryl carbonates by transesterifying with phenols in the presence of catalysts. The process entails isolating bisphenols from the product of the transesterification, and subjecting the remaining mixture which contains phenols and diaryl carbonates to flash distillation. The phenols and diaryl carbonates are distilled off and separated, and the diaryl carbonates are recovered.

Abstract: The title compounds are prepared from organic carbonates having at least one aliphatic ester group and phenolic compounds by transesterification in the presence of a transesterification catalyst known per se at 60.degree.-320.degree. C. in a column-type reactor with multiple recycling of the reaction products into this reactor with intermediate storage of the product streams.

Abstract: Carbonic diesters containing at least one aromatic ester group can be prepared from carbonic diesters containing at least one aliphatic ester group by transesterification using a phenol, titanium dioxide having a surface area of at least 20 m.sup.2 /g as determined by the BET method being used as catalyst.

Abstract: Diaryl carbonates are prepared from dialkyl carbonates and phenolic compounds by transesterification in the presence of a transesterification catalyst at 60.degree.-320.degree. C. in an apparatus composed of two columns in a continuous procedure. In the first column, the starting materials form essentially the associated alkyl aryl carbonate, from which, in the second column, the diaryl carbonate is produced by further transesterification and disproportionation.

Abstract: Diaryl carbonates are prepared by reaction from dialkyl carbonates and phenols using conventional transesterification catalysts in a specific mass-coupled and energy-coupled combination of columns, for example according to FIG. 1, in which the reference numerals have the meaning specified in the description.

Abstract: A process is described for preparing aromatic carbonates by transesterification of aliphatic carbonates with phenolic compounds in the presence of titanium compounds known per se, in which, before work-up, the transesterification mixture is cooled to a temperature below 120.degree. C., during which the mixture must remain liquid, the titanium-containing precipitate which is deposited is separated off, and the aromatic carbonate is then obtained by methods which are conventional per se.

Abstract: Thermoplastic moulding compounds of 99.8-95% by weight of a mixture consisting of an aromatic polycarbonate, a graft polymer and optionally a thermoplastic vinyl polymer and/or the usual additives and 0.2 to 5% by weight of a polyalkylene ether which has been grafted with a polymer of C.sub.1 -C.sub.6 alkyl(meth)acrylates, cyclo-alkylacrylates or -methacrylates and optionally styrene or .alpha.-methylstyrene.

Abstract: A process for the continuous splitting of polycarbonates into dihydroxy compounds and carbonic acid esters is disclosed. Accordingly there are reacted in a distillation column a polycarbonate resin and a monohydroxy compound in the presence of a transesterification catalyst. The polycarbonate, in molten form or as a solute, is continuously fed into the upper part of the column and the monohydroxy compound in vapor phase is continuously fed into the lower part of the column. The resulting carbonic acid ester and dihydroxy compounds are continuously being removed from the column. The process is eminently suitable for the recycling of polycarbonate waste.

Abstract: Aromatic and aliphatic-aromatic carbonic acid diesters can be obtained by transesterification of carbonic acid diesters containing aliphatic ester groups if polymeric hydroxystannoxanes are employed as catalysts.

Abstract: Crosslinked copolymers ofA) cyclic aliphatic esters andB) cyclic aliphatic carbonatesin which part of B contains crosslinking-active side groups,their production and their use for the production of films.