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

Abstract: The invention relates to the continuous production of polyurethane and polyurethane urea prepolymers by reaction of polyisocyanates with isocyanate-reactive compounds in a mixing nozzle.

Abstract: The present invention relates to a process for the continuous production of carbonates having aromatic ester groups by the reaction of aromatic hydroxy compounds with phosgene in the presence of heterogeneous catalysts, phosgene still present being removed from the stream of waste gas by returning the waste gas to an additional reactor.

Abstract: This invention relates to a process for the production of polycarbonate agglomerate of high bulk density from polycarbonate solutions, in which the organic solvent is stripped from a solution of polycarbonate by means of steam, and which is characterised in that the resulting suspension of polycarbonate particles, condensed water and water- and solvent vapor is fed in a tube or tubular heat exchanger to a separator which is partially filled with water and which is under elevated pressure. The polycarbonate agglomerates are discharged, together with part of the water, via a pressure lock at the bottom of the separator.

Abstract: The present invention provides a process for the isolation of partially crystalline polycarbonate powder or oligocarbonate powder from solutions thereof, in which process the organic solvent of a polycarbonate solution is vaporized in a heat exchanger, optionally with incorporation of steam, or in a holding tube with incorporation of steam and the pasty mixture of concentrated solution, solvent vapor and optionally water is separated in a separator. In this process, the solvent vapor is condensed in a heat exchanger downstream from the separator. The solvent is vaporized in the heat exchanger by indirect input of heat through the heat exchanger walls and vaporization may be promoted by preheating the polycarbonate or oligocarbonate solution in an upstream heat exchanger or by introducing steam or both.

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: 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.

Abstract: The invention relates to a two-step melt process for the production of thermoplastic, solvent-free, low-branching polycarbonates with low --OH terminal group content using a self-cleaning high-viscosity reactor.

Abstract: The present invention relates to a transesterification process for producing thermoplastic polycarbonates with the use of fixed bed catalysts.

Abstract: The invention relates to a process for preparing a diaryl carbonate by oxidative carbonylation of the basic aromatic hydroxy compound, in which the aromatic hydroxy compound is the one which is eliminated during melt polycondensation of this diaryl carbonate with a bisphenol. Accordingly the invention also relates to the preparation of polycarbonates by melt polycondensation of diaryl carbonates with bisphenols in which the aromatic hydroxy compounds which is eliminated is used again to prepare the diaryl carbonate. In the event that the aromatic hydroxy compound eliminated is also the basic unit in the bisphenol used, proportions of it may be used to prepare both the diaryl carbonate and the bisphenol.

Abstract: The present invention relates to the use of cyclic carbonates as demoulding agents for thermoplastic polycarbonates, and to the incorporation of these cyclic carbonates into the thermoplastic polycarbonates.

Abstract: The present invention relates to a process for the continuous production of diaryl carbonates by reaction of aromatic hydroxy compounds with phosgene in the presence of heterogeneous catalysts.

Abstract: This invention relates to a process for producing granulated polymer materials from polymer solutions, in which organic solvent of the polymer solution is evaporated in a heat exchanger, optionally with the admixture of steam, or in a holding tube with the admixture of steam, and the paste-like mixture of concentrated solution, solvent vapour and optionally of condensed steam is separated in a separator provided with rotating built-in components for cleaning off the walls. The pre-concentrated polymer solution is further concentrated in the separator by supplying heat by way of heating the separator walls or the rotating built-in components and by the shearing energy of the rotating built-in components.Residual degassing of the solvent is effected before granulation, e.g. in the discharge extruder of the separator which is provided with rotating built-in components, through one or more degassing zones, optionally by the additional admixture of entraining media, such as inert gas or steam, for example.

Abstract: The invention relates to a transesterification process for the production of thermoplastic, solventless oligo-/polycarbonates in which aromatic diphenols and carbonic acid diaryl esters are combined and reacted in gaseous form.

Abstract: The present invention provides a two-stage melt process for the manufacture of thermoplastic, solvent-free, low-branched polycarbonates with low OH end-group contents with the use of ammonium or phophonium catalysts in the first stage and alkali and alkaline earth catalysts in the second stage.

Abstract: The present invention relates to the continuous production of polyurethane and polyurethane urea elastomers by reaction of polyisocyanates with isocyanate-reactive compounds in a mixing nozzle.

Abstract: The present invention relates to a process for the continuous preparation of organic mono- or polyisocyanates by the reaction of the mono- or polyamines corresponding to the mono- or polyisocyanates with phosgene dissolved in an organic solvent. The phosgene solution and the amine component, optionally also in the form of a solution, are brought together inside a nozzle (1) by subjecting the stream of one component to a constriction (3) and supplying the other component into this constriction (3) from the side as partial streams through several apertures (5).

Abstract: This invention relates to a process for the continuous production of an organic monoisocyanate or polyisocyanate in a single stage reaction. A reaction mixture is formed by continuously mixing, at a temperature elevated above room temperature but not exceeding about 150.degree. C., a solution in a substantially inert organic solvent of a monoamine or polyamine corresponding to the monoisocyanate or polyisocyanate and a solution in a substantially inert organic solvent of phosgene. The reaction mixture is continuously passed upwards from below through a reaction column comprising at least 10 separate chambers separated by perforated plates, wherein each perforation of said perforated plates has a diameter of less than about 20 mm.

Abstract: Optionally-foamed intumescent compositions obtained by reacting(a) polyisocyanates with(b) phosphorus-containing condensation products having at least 2 hydroxyl groups and obtained by condensing primary or secondary monoamines and/or polyamines optionally containing OH-groups, carbonyl compounds and dialkyl phosphites, optionally followed by alkoxylation, and(c) more than bifunctional polyethers having an average OH-number of from 150 to 500 which have been obtained by the addition of alkylene oxides, of which from 50 to 100% by weight consist of ethylene oxide, with low molecular weight starters, and(d) cyanuric acid and/or cyanuric acid derivatives, and(e) optionally water and(f) optionally other organic compounds containing isocyanate-reactive hydrogen atoms,are used, for example, as cavity-filling, gap-sealing or coating materials.