Abstract:
The present invention relates to a process for the production of low-halogen-content polybiphenyl sulfone polymers, to the resultant polybiphenyl sulfone polymers, to polybiphenyl sulfone polymers having less than 400 ppm content of polymer-bonded halogen, to thermoplastic molding compositions comprising these polybiphenyl sulfone polymers, and to their use for the production of moldings, of fibers, of films, of membranes, or of foams.
Abstract:
A process is proposed for the treatment of a recycling stream (1) from a plant for the production of polyarylene ether sulfones via polycondensation of aromatic bishalogen compounds and of aromatic bisphenols or their salts in the presence of at least one alkali metal carbonate or ammonium carbonate or alkali metal hydrogencarbonate or ammonium hydrogencarbonate in an N-alkyl-2-pyrrolidone as solvent, comprising from 60 to 90% by weight of water, from 10 to 40% by weight of the N-alkyl-2-pyrrolidone and, as contaminant detrimental to specification, up to 5000 ppm by weight of the alkylsuccinimide corresponding to the N-alkyl-2-pyrrolidone and, alongside this, up to 1000 ppm by weight of other substances with higher boiling point than N-alkyl-2-pyrrolidone, in particular inorganic salts, based in each case on the total weight of the recycling stream (1), where the entirety of the components gives 100% by weight, giving a pure N-alkyl-2-pyrrolidone stream (2) which can be returned to the plant for the production of polyarylene ether sulfones, via a final distillation process in a final column (K), which comprises preceding the final distillation by a preliminary purification by evaporation in one or more evaporator stages for reducing the level of inorganic salts, where one or more vapor streams (3, 4, 5) are obtained which are introduced as feed streams into the final column (K), and where the bottom stream from the last evaporator stage is removed and the bottom stream from the final column (K) is recycled in full into the last evaporator stage.
Abstract:
A process is proposed for the treatment of a recycling stream (1) from a plant for the production of polyarylene ether sulfones via polycondensation of aromatic bishalogen compounds and of aromatic bisphenols or their salts in the presence of at least one alkali metal carbonate or ammonium carbonate or alkali metal hydrogencarbonate or ammonium hydrogencarbonate in an N-alkyl-2-pyrrolidone as solvent, comprising from 60 to 90% by weight of water, from 10 to 40% by weight of N-alkyl-2-pyrrolidone and, as contaminant detrimental to specification, up to 5000 ppm by weight of the alkylsuccinimide corresponding to the N-alkyl-2-pyrrolidone and, alongside this, up to 1000 ppm by weight of other substances with higher boiling point than N-alkyl-2-pyrrolidone, in particular inorganic salts, based in each case on the total weight of the recycling stream (1), where the entirety of the components gives 100% by weight, giving a pure N-alkyl-2-pyrrolidone stream (2) which can be returned to the plant for the production of polyarylene ether sulfones, via a final distillation, which comprises carrying out the final distillation process in a partitioned column (TK), with a partition (T) arranged in the longitudinal direction of the column and dividing the space within the partitioned column (TK) into an input region (A), an output region (B), an upper undivided region (C) of the column, and a lower undivided region (D) of the column, the recycling stream (1) being introduced into the column in the input section (A) of the same, and being separated, in the partitioned column (TK), into a bottom stream (7) comprising N-methylsuccinimide, an overhead stream (8) comprising water, and a pure NMP stream, as side stream (2) from the output section (B).
Abstract:
N-alkylpyrrolidone and, as contaminant alongside this, the corresponding N-alkyl-succinimide, to give a pure solvent stream which meets the requirements for use in a process for the production of polymers, where compounds of higher and lower boiling point than the N-alkylpyrrolidone are removed by distillation, which comprises, prior to, during, or after the distillative purification process, adding a hydroxide of an alkali metal or of an alkaline earth metal in a molar amount corresponding to a molar ratio of at least 0.1:1 for this hydroxide with respect to the respective N-alkylsuccinimide in the appropriate solvent stream present prior to, during, or after the distillative purification process.
Abstract:
The present invention relates to a process for the production of low-halogen-content polybiphenyl sulfone polymers, to the resultant polybiphenyl sulfone polymers, to polybiphenyl sulfone polymers having less than 400 ppm content of polymer-bonded halogen, to thermoplastic molding compositions comprising these polybiphenyl sulfone polymers, and to their use for the production of moldings, of fibers, of films, of membranes, or of foams.
Abstract:
A process for treating a recycling stream from a plant for the production of polyarylene ether sulfones comprising 60 to 90% water, 10 to 40% N-alkyl-2-pyrrolidone, up to 5000 ppm by weight of the alkylsuccinimide corresponding to the N-alkyl-2-pyrrolidone, up to 1000 ppm by weight of other substances with higher boiling point than N-alkyl-2-pyrrolidone, giving N-alkyl-2-pyrrolidone which can be recycled via a distillation column , preceded by preliminary purification in evaporator stage(s), giving vapor stream(s) which are introduced as feed streams into the distillation column, the bottom stream from the last evaporator stage being discharged and the bottom stream from the distillation column being recycled into the last evaporator stage, and the vapor stream from the last evaporator stage being introduced fully or partly into an additional column from which a top stream is introduced into the distillation column and a bottom stream is discharged.
Abstract:
The present invention relates to a process for the production of low-chlorine-content polybiphenyl sulfone polymers, to the polybiphenyl sulfone polymers obtainable in this way, to polybiphenyl sulfone polymers with less than 800 ppm content of organically bonded chlorine, to thermoplastic molding compositions and moldings, fibers, films, membranes, or foams comprising the polybiphenyl sulfone polymers mentioned, and also to their use for the production of moldings, of fibers, of films, of membranes, or of foams.
Abstract:
The present invention relates to a process for the production of low-chlorine-content polybiphenyl sulfone polymers, to the polybiphenyl sulfone polymers obtainable in this way, to polybiphenyl sulfone polymers with less than 800 ppm content of organically bonded chlorine, to thermoplastic molding compositions and moldings, fibers, films, membranes, or foams comprising the polybiphenyl sulfone polymers mentioned, and also to their use for the production of moldings, of fibers, of films, of membranes, or of foams.
Abstract:
A process is proposed for the treatment of a recycling stream (1) from a plant for the production of polyarylene ether sulfones via polycondensation of aromatic bishalogen compounds and of aromatic bisphenols or their salts in the presence of at least one alkali metal carbonate or ammonium carbonate or alkali metal hydrogencarbonate or ammonium hydrogencarbonate in an N-alkyl-2-pyrrolidone as solvent, comprising from 60 to 90% by weight of water, from 10 to 40% by weight of N-alkyl-2-pyrrolidone and, as contaminant detrimental to specification, up to 5000 ppm by weight of the alkylsuccinimide corresponding to the N-alkyl-2-pyrrolidone and, alongside this, up to 1000 ppm by weight of other substances with higher boiling point than N-alkyl-2-pyrrolidone, in particular inorganic salts, based in each case on the total weight of the recycling stream (1), where the entirety of the components gives 100% by weight, giving a pure N-alkyl-2-pyrrolidone stream (2) which can be returned to the plant for the production of polyarylene ether sulfones, via a final distillation in a final column (K), which comprises preceding the final distillation by a preliminary purification by evaporation in one or more evaporator stages for reducing the level of inorganic salts, where one or more vapor streams (3, 4, 5) are obtained, which are introduced as feed streams into the final column (K), and where the bottom stream from the last evaporator stage is removed, and where a substream (9) comprising 1.0% by weight to 10% by weight of the bottom stream (7) from the final column (K) is removed, and the rest of the bottom stream from the final column (K) is recycled into the last evaporator stage.
Abstract:
A process is proposed for the treatment of a recycling stream (1) from a plant for the production of polyarylene ether sulfones via polycondensation of aromatic bishalogen compounds and of aromatic bisphenols or their salts in the presence of at least one alkali metal carbonate or ammonium carbonate or alkali metal hydrogencarbonate or ammonium hydrogencarbonate in an N-alkyl-2-pyrrolidone as solvent, comprisingfrom 60 to 90% by weight of water, from 10 to 40% by weight of the N-alkyl-2-pyrrolidone and, as contaminant detrimental to specification, up to 5000 ppm by weight of the N-alkylsuccinimide corresponding to the N-alkyl-2-pyrrolidone and, alongside this, up to 1000 ppm by weight of other substances with higher boiling point than the N-alkyl-2-pyrrolidone, in particular inorganic salts, based in each case on the total weight of the recycling stream (1), where the entirety of the components gives 100% by weight, giving a pure N-alkyl-2-pyrrolidone stream (2) which can be returned to the plant for the production of polyarylene ether sulfones, via a final distillation process in a final column (K), wherein the final distillation is preceded upstream by a preliminary purification via evaporation in one or more evaporator stages for reduction of the content of high boilers compared to N-alkyl-2-pyrrolidone, giving one or more vapor streams (4, 5) which are fed as feed streams to the final column (K), the bottom stream (6) from the last evaporator stage being discharged and a substream (9) of the bottom stream (7) from the final column (K) being discharged and the rest of the bottom stream from the final column (K) being recycled into the last evaporator stage, and the one evaporator stage or the first of the plurality of evaporator stages being a column (WK) which is designed such that the top stream (10) therefrom still comprises a maximum of 200 ppm by weight of the N-alkyl-2-pyrrolidone, based on the total weight of the top stream therefrom, and is discharged, and the vapor streams (4, 5) being supplied to the final column (K) in vaporous form.