WO2006027110A1 - Procede de production de polycarbonate - Google Patents
Procede de production de polycarbonate Download PDFInfo
- Publication number
- WO2006027110A1 WO2006027110A1 PCT/EP2005/009162 EP2005009162W WO2006027110A1 WO 2006027110 A1 WO2006027110 A1 WO 2006027110A1 EP 2005009162 W EP2005009162 W EP 2005009162W WO 2006027110 A1 WO2006027110 A1 WO 2006027110A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- sup
- ppm
- maximum
- general formula
- carbonate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G64/00—Macromolecular compounds obtained by reactions forming a carbonic ester link in the main chain of the macromolecule
- C08G64/20—General preparatory processes
- C08G64/30—General preparatory processes using carbonates
- C08G64/307—General preparatory processes using carbonates and phenols
Definitions
- the invention relates to a process for the preparation of polycarbonate by the transesterification process by reacting an aromatic dihydroxyaryl compound and a diaryl carbonate in the melt.
- diphenyl carbonate In melt transesterification for the production of polycarbonate on an industrial scale, diphenyl carbonate is predominantly used.
- DPC diphenyl carbonate
- various technical routes are known. Many of the known methods dispense with the use of phosgene.
- a newer, phosgene-free method for the production of diphenyl carbonate is the oxidative direct carbonylation, in which phenol is reacted with oxygen and carbon monoxide.
- complex catalyst systems are used, which are typically a palladium compound, at least one transition or main group metal compound and an inorganic or
- a number of DPC production processes use dialkyl carbonates such as dimethyl carbonate (DMC) or dibutyl carbonate (DBC) or dialkyl oxalates as starting materials. These reactions also produce by-products such as salicylic compounds, alkylaryl carbonates, alkylphenyl derivatives (eg (methylphenyl) phenylcarbonates), dialkyl and alkylaryl ethers which, together with volatile derivatives of the metals used as transesterification catalysts (eg Zn, Ti, Sn, Pb, Tl) can contaminate the generated diphenyl carbonate.
- DMC dimethyl carbonate
- DBC dibutyl carbonate
- dialkyl oxalates dialkyl oxalates
- Alcohols under copper catalysis in the presence of hydrochloric acid can be chloro-organic or
- Copper organyl be introduced.
- traces of ethylene glycol, ethylene carbonate or derivatives thereof such as (2-hydroxyethyl) methyl carbonate, 1,2-ethylene (bismethyl carbonate) or 2-phenoxyethanol can be introduced into the product.
- a blatant disadvantage of all these processes is a low selectivity compared to phosgenation, ie the generation of by-products, and often the use of metalloids. metallic catalysts.
- the manufacturing process is generally followed by only a distillative purification of the product, so that separation of impurities on a trace scale is difficult to accomplish. This means that impurities are generated in the DPC via these synthetic routes, which have a very disturbing effect on the transparency and quality of the melt polycarbonate.
- a complete separation of these impurities often turns out to be too costly in economic terms, as shown in, for example, EP 592 900 A and EP 677 545 A prior art.
- the object is to provide a process for the preparation of polycarbonate, in which the quality of the polycarbonate is not impaired by impurities of the diaryl carbonate.
- the invention provides a process for preparing polycarbonate by the melt transesterification process by reacting at least one aromatic dihydroxyaryl compound and a diaryl carbonate in the melt, at least in the presence of a catalyst, using a carbonate formation reagent which contains at least
- Ar, Ar 1 to Ar 7 are each independently an aryl radical
- X is -Cl or -Br
- m is an integer from 1 to 3 and
- R 1 to R 4 each independently represent a linear, cyclic or branched alkyl radical having 1-20 C atoms, where R 1 and R 2 optionally together form a cycle, stand.
- the carbonate formation reagent used in the process according to the invention for the production of polycarbonate contains no impurities which affect the quality of the melt polycarbonate prepared according to the invention, e.g. in terms of color, mechanics, weather resistance and thermal stability, significantly reduce.
- the carbonate forming reagent which is erf ⁇ ndungsgem according to used for the production of polycarbonate, prepared by a process comprising at least the following steps: (a) reacting an alkaline aqueous solution of a compound ArOH with a solution of phosgene in an inert organic solvent, if appropriate in the presence of an organic catalyst, at least to form a diaryl carbonate
- step (b) at least one simple, preferably multiple, extraction of the reaction mixture obtained according to step (a) with an aqueous solution
- step (c) treating said in step (b) the resulting organic extract containing the Amsterdams ⁇ medium with a residual moisture content of at least 0.5 wt.%, by distillation and / or steam distillation with introduction of water or steam at temperatures from 40 to 180 0 C, preferably 50 to 150 0 C 5, more preferably 60 to 135 ° C.
- step (d) Distillative purification of the reaction mixture obtained according to step (c), which is optionally concentrated, the diaryl carbonate being taken off as top product or in the side stream and at least 0.2% by weight, preferably at least 0.3% by weight, more preferably at least 0.5% by weight (based on the ArOH mass used) is taken from the bottom product.
- a carbonate-forming reagent prepared by this process contains no impurities, by-products or the like, which substantially impair the quality of a melt polycarbonate produced therefrom.
- the quality of the carbonate-forming reagent produced by means of phosgene is sufficient to produce a melt polycarbonate of excellent quality and transparency. Existing impurities or the like. do not impair the quality of the molten polycarbonate.
- systemic by-products are formed which limit the use of a phosgene-free diphenyl carbonate mixture or diaryl carbonate mixture in polycarbonate synthesis or reduce the quality of the polycarbonate produced.
- the carbonate forming reagent is economically very efficient to produce by this method due to its relatively simple technical implementation.
- the preparation of carbonic acid diaryl esters (diaryl carbonates) by the phase boundary process is known in principle from the literature (eg EP-A 12 16 981, EP-A 12 16 982 or EP-A 12 19 589).
- the carbonate forming reagent in the context of the present invention is also referred to simply as carbonic acid diarylester.
- the alkali used in step (a) may be an alkali metal hydroxide solution (Na, K, Li, Ca hydroxide), preferably sodium hydroxide solution and is preferably used in the process according to the invention as 20 to 55% by weight, more preferably 30 to 50% by weight. -% solution used.
- Phosgene can be used liquid, gaseous or dissolved in an inert solvent.
- Suitable monophenols ArOH for use in the reaction are phenols of the formula (I) or (H)
- R represents hydrogen, tert-butyl, halogens, a branched or unbranched CrQ 2 -alkyl, C 7 -C 42 -alkylaryl or a C 6 -C 10 -aryl radical, a car-boxyalkyl or -aryl radical ( ⁇ CO 2 R 6 ).
- the substituents R 1, R 2, R 3, R 4, R 5 and R 6 are independently members of the set of moieties defined by R, except that R 6 should not be H or halogen.
- phenol itself, alkylphenols such as cresols, xylenols, p-tert-butylphenol, p-cumylphenol, pn-octylphenol, p-iso-octylphenol, pn-nonylphenol and p-iso-nonylphenol, halophenols such as p-chlorophenol, 2,4-dichlorophenol, p-bromophenol and 2,4,6-tribromophenol, arylphenols such as 4-phenylphenol, hydroxybenzoic acid esters such as methyl, isopropyl or phenyl salicylate or p-hydroxy (benzoic acid methyl ester).
- the cresols and hydroxybenzoic acid esters are preferred, phenol being particularly preferred.
- Inert organic solvents used in this process are, for example, dichloromethane, toluene, the various dichloroethanes and chloropropane compounds, chlorobenzene and chlorotoluene, preferably dichloromethane is used.
- the reaction procedure according to step (a) is preferably carried out continuously and preferably in a plug flow without much back-mixing. This can thus be done for example in tubular reactors.
- the mixing of the two phases (aqueous and organic phase) can be realized by built-in tube diaphragms, static mixers and / or pumps, for example.
- the reaction procedure is divided into two successive stages.
- the aqueous phase is mixed with the organic phase in an orifice, nozzle or dynamic mixer.
- a nozzle is to be used, for example a confused-difrusor combination provided with bores or a suddenly narrowed tube.
- Behind the mixing element is a cooler, preferably with a liquid distributor, for cooling the reaction mixture to a maximum of 50 0 C, preferably a maximum of 40 0 C provided.
- the mixing power is too low, the reaction is incomplete, i. the monophenol is not completely reacted with the phosgene, so that, on the one hand, monophenol enters the wastewater and, on the other hand, the intermediate product of the aryl chloroformate is dragged into the end product. If the mixing performance is too high, a higher saponification and cleavage of the phosgene and the carbonic diaryl ester occurs, so that, on the one hand, monophenol enters the wastewater and, on the other hand, a significantly increased phosgene excess is required.
- the reaction of the first stage is started by bringing the reaction components phosgene, inert solvent, which preferably serves first as a solvent for the phosgene, and phenol, which is preferably already previously dissolved in the alkali, are brought into contact.
- the residence time in the continuous process of the first stage is in the range of 2 seconds to 300 seconds, preferably in the range of 4 seconds to 200 seconds.
- the pH of the first stage is adjusted by the ratio of ⁇ lkalilauge / Phe ⁇ ol / phosgene, that the pH in the range of 11.0 to 12.0, preferably 11.2 to 11.8, particularly preferably 11 , 4 to 11.6.
- the reaction temperature in the first stage is maintained by cooling to a maximum of 40 0 C, preferably a maximum of 35 ° C.
- the reaction is completed to the carbonic acid diaryl ester.
- the mixing of the two phases (aqueous and organic phase) in the second stage takes place at regular intervals by means of preferably static or dynamic dispersing agents.
- static elements are preferably diaphragms, nozzles or narrowed pipe sections are used. In the latter, additional installations (static mixers) can be used for stream splitting and mixing.
- the pressure drop per dispersing element is preferably 0.1 to 0.5 bar.
- the velocity in the narrowest cross-section of the element is typically 2 to 10 m / s, preferably 3 to 9 m / s, most preferably 4 at 7 m / s.
- the mixing time (residence time in the dispersing) is at most 0.5 s, preferably 0.01 to 0.1 s.
- the residence time between two successive dispersing agents is 3 to 12 s, preferably 5 to 10 s.
- Suitable dynamic mixers are, for example, pumps or generally rotor-stator systems.
- the residence times of the second stage are 1 minute to 2 hours, preferably 2 minutes to 20 minutes, most preferably 3 minutes to 15 minutes.
- a catalyst is fed zuge ⁇ at the beginning of the second stage.
- the reaction of the process is preferably cooled.
- the reaction temperature is maintained by cooling to a maximum of 50 ° C, preferably a maximum of 40 0 C, most preferably a maximum of 35 ° C. It may be advantageous to add the catalyst at several, preferably at two, points in the second stage of the reaction in the continuous process.
- an intermediate buffering can also be carried out, for example, in a stirred residence vessel while maintaining the mixed phases.
- Suitable catalysts are, for example, tertiary amines, N-alkylpiperidines or onium salts.
- onium salts the scope of the present invention is understood to mean compounds such as PR 4 X and NR 4 X, where R can be an alkyl and / or aryl radical and / or an H and X is an anion.
- Tributylamine, triethylamine and N-ethylpiperidine are preferably used. Very particular preference is given to N-ethylpiperidine.
- the concentration of the catalysts is 0.0001 mol% to 0.1 mol%, preferably 0.01 mol% to 0.075 mol%, based on the phenol used.
- the pH is controlled by measuring the pH (preferably measured online in the continuous process by methods known in the art) and adjusting the pH accordingly by adding the caustic.
- the amount of added alkali metal hydroxide solution is adjusted so that the pH after the second process stage is in the range of 7.5 to 10.5, preferably 8 to 10, particularly preferably 8.2 to 9.5.
- Phosgene is run relative to the phenol in the ratio of 1.01 to 1.14 mol%, preferably 1.05 to 1.10 mol%.
- the solvent is mixed in such a way that the carbonic acid diphenyl ester is present in a 5 to 60% strength solution, preferably 20 to 45% strength solution, after the reaction.
- the organic phase containing the carbonic acid diarylester is customarily washed with an aqueous liquid and separated from the aqueous phase as far as possible after each washing operation (extraction with an aqueous solution according to step (b)).
- the laundry is preferably carried out with desalinated water.
- the carbonic acid diarylester solution is usually cloudy after washing and separation of the washing liquid.
- the washing liquid used is aqueous liquids for separating off the catalyst, for example dilute mineral acids such as HCl or H 3 PO 4 , and deionized water for further purification.
- the concentration of HCl or H 3 PO 4 in the washing liquid may be, for example, 0.5 to 1.0% by weight.
- the extraction takes place at least twice.
- phase separation devices for separating the washing liquid from the organic phase it is possible in principle to use known separating devices, such as separating vessels, phase separators, centrifuges and coalescers, or else combinations of these devices.
- step (c) the organic extract containing the solvent having a residual moisture content of at least 0.5% by weight of step (b) is thermally treated with water.
- This step is carried out at temperatures of 40 0 C to 180 0 C, preferably 50 to 150 0 C, particularly preferably 70 to 135 ° C, by means of distillation and / or steam distillation with introduction of water or steam (steam stripping).
- the residual moisture contained in the organic extract or the optionally added liquid water or the added water vapor act as a drag gas (stripping gas) to remove the solvent, residues of the phenol and impurities.
- a first possible embodiment is the distillation of the organic extract with a residual moisture content of at least 0.5% by weight in the temperature range mentioned.
- the organic extract which is optionally concentrated, freed of solvent and residual phenol.
- a second, preferred embodiment is the steam distillation of the optionally concentrated organic extract while introducing water or steam.
- the distillate is preferably condensed and the resulting solvent-water mixture, preferably without prior phase separation, recycled into the reaction.
- the treatment according to step (c) may be carried out in one or more temperature and pressure stages, e.g. in different distillation columns and / or stripping vessels. If several stages are used, it is preferred to work with a temperature profile rising in the direction of flow and / or a decreasing pressure profile.
- step (d) a distillative purification (fine distillation) of the diaryl carbonate remaining in the bottom in step (c).
- Characteristic of this step is that at least 0.2 wt.%, Preferably at least 0.3 wt.%, Particularly preferably at least 0.5 wt.%, (Based on the ArOH mass used) is taken from the bottom product.
- the diaryl carbonate obtained from the bottom product is not returned to the process.
- Step (d) can be one or more stages.
- Various methods of distillation known in principle can be used. For example, the distillation can be carried out in two stages, wherein in a first column first ArOH and other lower-boiling compounds are taken overhead and the diaryl carbonate remains in the bottom.
- the high boiler fraction can be returned to the process.
- the diaryl carbonate can then be removed as top product or on one of the upper separation trays.
- the bottoms of this column circulated, for example, by means of a circulation evaporator, are then taken off a corresponding subset as purges.
- An alternative variant is the use of a dividing wall column, in which high boilers are taken as Kop ⁇ rodukt, a circulating bottom product, from which a purge stream is diverted, and diaryl carbonate is taken as a side stream.
- a preferred variant is based on the embodiment of EP 784 048 A developed for a substance phosgenation process.
- the fine distillation of the diaryl carbonate takes place here in a single distillation column.
- the reaction mixture from step (c) is fed to one of the upper trays, at the top of the column, a product is withdrawn, the bottom is circulated by means of a circulation evaporator, wherein a purge stream is removed and the diaryl carbonate in the side stream preferably on a bottom below the Height of feed feed taken.
- a further separation step can be carried out, in which, by known methods, such as distillation, extraction, membrane separation or precipitation, an enrichment of the high boilers to be separated from the present in high concentration diaryl carbonate is made.
- a stream comprising about 0.5 to 5% of the feed stream from step (c) may be withdrawn from the bottoms and subjected to further distillation, eg, in a column or a falling film evaporator. The bottom of this distillation, the said portion is removed as purge, while the distillate can be recycled to the Feindestillationskolonne or to another point in the process.
- These purification steps may be, for example, continuously guided such that the bottom temperature in the distillation of at least 150 9 C to 310 0 C, preferably at least 160 located to 230 0 C.
- the pressure necessary to carry out the distillation is from 1 to 1000 mbar, preferably from 5 to 100 mbar.
- the carbonic acid diaryl esters prepared by the preferred method using phosgene are distinguished by a very high purity with GC purities (cool on column method) of at least 99.99%, preferably at least 99.9925%, very particularly preferably at least 99.995%, and extremely good transesterification behavior, so that a polycarbonate can be produced in excellent quality.
- the carbonate forming reagent which is used in the process according to the invention for the production of polycarbonate is characterized by a content of
- Diphenyl carbonate is particularly preferred.
- a hydroxyaromatic of the general formula ArOH preferably of the formula (I) or (II), with phenol being particularly preferred.
- Important representatives of this group are dealkylation products of the trialkylamines and alkylpiperidines used as catalysts. In particular phenylpiperidylurethane should be mentioned here.
- Important representatives are the p- and especially the o-Phenoxybenzoeklarivate and here again especially the phenyl esters.
- hydroxyarylcarboxylic acid derivatives of the general formula Z 2 O-Ar 4 COOAr At most 100 ppm, preferably at most 10 ppm, particularly preferably at most 5 ppm, in total of hydroxyarylcarboxylic acid derivatives of the general formula Z 2 O-Ar 4 COOAr.
- Important representatives are the p- and especially the o-Hydroxybenzoeklarephenylester and their carbonates. Due to the similar boiling point, the separation of phenyl salicylate from
- Maximum of 10 ppm, preferably at most 5 ppm, particularly of the formula Z is preferably more than 1 ppm, in sum of o, o ⁇ -Biphenylencarbonat, dibenzofuran and Biphenyldiolderivaten 3 OAr 5 - Ar 5 OZ. 4
- Important representatives are the o, o ⁇ o, p ⁇ - and p, p ⁇ -Dihydroxybiphenyle, and their mono- and diaryl carbonates.
- a phenol which is as low in biphenyl diol as possible and to avoid oxidative conditions such as the presence of oxygen during the process. This can be achieved by methods known to the person skilled in the art, for example by blowing or passing inert gases, degassing the educt streams or adding reducing agents.
- a phenol is used for the synthesis of diphenyl carbonate which contains less than 500 ppm, preferably less than 200 ppm, more preferably less than 100 ppm, of dihydroxybenzenes.
- Ar, Ar 1 to Ar 7 are each independently an aryl radical, preferably in each case a phenyl radical,
- R 1 to R 4 each independently represent a linear, cyclic or branched alkyl radical having 1-20 C atoms, wherein R 1 and R 2 may together form a cycle.
- the carbonate forming reagent contains no further organic impurities in an amount of more than 100 ppm and no further elements except C, H, N, P, Cl and O in the scale of more than 5 ppm. Possibly. existing metals are particularly preferably contained only in amounts of at most 1 ppm.
- the carbonate forming reagent is used in the production of polycarbonate by the melt transesterification method by reacting at least one aromatic dihydroxyaryl compound and the carbonate forming reagent containing a diaryl carbonate in the melt at least in the presence of a catalyst.
- the melt transesterification process is basically known from the prior art. The implementation of the method is described for example in WO 02/077067.
- suitable dihydroxyaryl compounds are those of the formula
- HO-Z-OH in which Z is an aromatic radical having 6 to 30 C atoms, which may contain one or more aromatic nuclei, may be substituted and may contain aliphatic or cycloaliphatic radicals or alkylaryls or heteroatoms as bridge members.
- dihydroxyaryl compounds are: dihydroxybenzenes, dihydroxydiphenyls, bis (hydroxyphenyl) alkanes, bis (hydroxyphenyl) cycloalkanes, bis (hydroxyphenyl) aryls, bis (hydroxyphenyl) ethers, bis (hydroxyphenyl) ketones, bis - (hydroxyphenyl) sulfides, bis (hydroxyphenyl) sulfones, bis (hydroxyphenyl) sulfoxides, l, r-bis (hydroxyphenyl) diisopropylbenzenes, and their ring-alkylated and ring-halogenated compounds.
- Preferred dihydroxyaryl compounds are, for example: resorcinol, 4,4'-dihydroxydiphenyl, bis (4-hydroxyphenyl) methane, bis (3,5-dimethyl-4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) - diphenylmethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1-bis (4-hydroxyphenyl) -1- (1-naphthyl) ethane, 1,1-bis- (4-hydroxyphenyl) -1- (2-naphthyl) ethane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (3-methyl-4-hydroxyphenyl) -propane, 2,2-bis- (3,5-dimethyl-4-hydroxyphenyl) -propane, 2,2-bis (4-hydroxyphenyl) -1-phenyl-propane, 2,2-bis (4-hydroxyphenyl ) -hexa-fluor
- dihydroxyaryl compounds are: resorcinol, 4,4'-dihydroxydiphenyl, bis- (4-hydroxyphenyl) -diphenyl-methane, 1,1-bis- (4-hydroxyphenyl) -1-phenyl-ethane, bis- (4-hydroxy - phenyl) -1- (1-naphthyl) ethane, bis (4-hydroxyphenyl) -1- (2-naphthyl) ethane, 2,2-bis- (4-hydroxyphenyl) -propane, 2, 2-bis (3,5-dimethylo-4-hydroxyphenyl) -propane, 1,1-bis (4-hydroxyphenyl) -cyclohexane, 1,1-bis (3,5-dimethyl-4-hydroxyphenyl) -cyclohexane 1,1-Bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 1,1'-bis (4-hydroxyphenyl)
- the dihydroxyaryl compounds can also be used with residual contents of the monohydroxyaryl compounds from which they have been prepared, or the low molecular weight oligocarbonates with residual contents of the monohydroxyaryl compounds which have been removed in the preparation of the oligomers.
- the contents may be up to 20%, preferably 10%, more preferably up to 5% and most preferably up to 2%.
- the diphenyl carbonate is admixed with 1.02 to 1.30 mol, preferably with 1.04 to 1.25 mol, particularly preferably with 1.06 to 1.22 mol, very particularly preferably with 1.06 to 1, 20 moles per mole of dihydroxyaryl used.
- R, R 1 and R "independently of one another are H, optionally branched C 1 -C 34 alkyl / cycloalkyl, C 7 -C 34 -alkylaryl or C 6 -C 34 -aryl
- R can also be -COO-R '" where R '''may be H, optionally branched C 1 -C 34 alkyl / cycloalkyl, C 7 -C 34 -AhCyIaTyI or C 0 -C 34 aryl
- R may not be H, but R' and R ".
- Examples of such monohydroxyaryl compounds are: 1-, 2- or 3-methylphenol, 2,4-dimethylphenol 4-ethylphenol, 4-n-propylphenol, 4-iso-propylphenol, 4-n-butylphenol, 4-isobutylphenol, 4- tert-butylphenol, 4-n-peniylphenol, 4-n-hexylphenol, 4-iso-octylphenol, 4-n-nonylphenol, 3-pentadecylphenol, 4-cyclohexylphenol, 4- (1-methyl-1-phenylethyl) -phenol, 4-phenylphenol, 4-phenoxyphenol, 4- (1-naphthyl) -phenol, 4- (2-naphthyl) -phenol, 4-trirylphenol, methyl salicylate, ethyl salicylate, n-propyl salicylate, iso-propyl salicylate, n-butyl salicylate, iso- Butyl salicylate, tert-
- a monohydroxyaryl compound whose boiling point is above that of the monohydroxyaryl compound used to prepare the diaryl carbonate used must be chosen.
- the monohydroxyaryl compound can be added at any time in the course of the reaction. It is preferably added at the beginning of the reaction or else at any point in the course of the process.
- the proportion of free monohydroxyaryl compound may be 0.2-20 mol%, preferably 0.4-10 mol%, based on the dihydroxyaryl compound.
- the end groups can also be altered by concomitant use of a diaryl carbonate whose base mono-hydroxyaryl compound has a higher boiling point than the base monohydroxyaryl compound of the main diaryl carbonate used.
- the diaryl carbonate can be added at any time during the course of the reaction. It is preferably added at the beginning of the reaction or else at any point in the course of the process.
- the proportion of the diaryl carbonate with the higher-boiling base monohydroxyaryl compound in the total amount of diaryl carbonate used can be 1 to 40 mol%, preferably 1 to 20 mol% and particularly preferably 1 to 10 mol%.
- Catalysts which are used in the melt transesterification process for preparing polycarbonates are the basic catalysts known in the literature, such as, for example, alkali metal and alkaline earth oxides and oxides, but also ammonium or phosphonium salts, referred to below as onium salts.
- Onium salts, more preferably phosphonium salts, are preferably used in the synthesis.
- Phosphonium salts in the context of the invention are those of the general formula:
- R 1 "4 are the same or different Q-Cio-alkyls, C 6 -C 14 -aryls, C 7 -C 15 -arylalkyls or C 5 -C 6 -cycloalkyls, preferably methyl or C 6 -C 14 -aryls, are particularly preferred May be methyl or phenyl, and X "may be an anion such as hydroxide, sulfate, hydrogensulfate, bicarbonate, carbonate or a halide, preferably chloride or an alkylate or arylate of the formula -OR, where R is a C ⁇ -Cu-aryl , C 7 -C 5 -Arylalkyl or Cs-C ⁇ -cycloalkyl, preferably phenyl.
- Preferred catalysts are tetraphenylphosphonium chloride, tetraphenylphosphonium hydroxide and tetraphenylphosphonium phenolate, particular preference is given to tetraphenylphosphonophenolate.
- catalysts may be used alone or in addition to the onium salt as cocatalyst to increase the rate of polycondensation.
- alkaline salts of alkali metals and alkaline earth metals such as hydroxides, alkoxides and acryloxyde of lithium, sodium and potassium, preferably hydroxides, alkoxides or acryloxyde of sodium.
- alkaline salts of alkali metals and alkaline earth metals such as hydroxides, alkoxides and acryloxyde of lithium, sodium and potassium, preferably hydroxides, alkoxides or acryloxyde of sodium.
- sodium hydroxide and sodium phenolate as well as the disodium salt of 2,2-bis- (4-hydroxyphenyl) -propane.
- the amounts of alkaline salts of alkali metals and alkaline earth metals alone or as co-catalyst may range from 1 to 500 ppb, preferably from 5 to 300 ppb, and most preferably from 5 to 200 ppb, each calculated as sodium and based on polycarbonate to be formed.
- alkaline salts of alkali metals and alkaline earth metals can already be used in the preparation of the oligocarbonates, that is to say at the beginning of the synthesis, or else be added only before the polycondensation in order to suppress undesirable side reactions.
- the addition of the catalysts takes place in solution in order to avoid harmful overconcentration during the metering.
- the solvents are system and process inherent compounds such as dihydroxyaryl compounds, diaryl carbonates or monohydroxyaryl compounds. Particular preference is given to monohydroxyaryl compounds because it is familiar to the person skilled in the art that the dihydroxyaryl compounds and diaryl carbonates readily change and decompose at already slightly elevated temperatures, in particular under the action of a catalyst.
- These include polycarbonate grades.
- the preferred compound is phenol. That's why phenol is already available mandatory, because the preferably used catalyst tetraphenylphosphonium phenolate is isolated in the production as a mixed crystal with phenol.
- thermoplastic polycarbonates are represented by the formula
- the bracket denotes a n-times repeating structural unit, where Z is as defined above.
- the polycarbonates have an extremely low content of cations and anions of in each case not more than 60. ppb, preferably not more than 40 ppb and especially preferably not more than 20 ppb (as sodium).
- cations are those of alkali and alkaline earth metals, which may originate, for example, as an impurity from the raw materials used and the phosphonium and ammonium salts.
- Other ions such as Fe, Ni, Cr, Zn, Sn, Mo, Al ions and their homologues can be contained in the raw materials or originate from the materials of the plant used by removal or corrosion. The content of these ions is in the sum a maximum of 2 ppm, preferably at most 1 ppm and more preferably at most 0.5 ppm.
- anions are those of inorganic acids and organic acids in equivalent amounts (e.g., chloride, sulfate, carbonate, phosphate, phosphite, oxalate).
- the aim is thus the smallest amounts that can be achieved only by using pure raw materials.
- pure raw materials are e.g. only available after purification processes such as recrystallization, distillation, topping with washes.
- the weight average molecular weights (M w ) obtained are from 15,000 to 40,000, preferably from 17,000 to 36,000, particularly preferably from 17,000 to 34,000 g / mol, where M w is determined by the relative Viscosity according to the Mark-Houwink correlation (JMG Cowie, Chemistry and Physics of synthetic polymers, Vieweg textbook, Braunschweig / W ⁇ esbaden, 1997, page 235) is determined.
- the polycarbonates can be selectively branched.
- Suitable branching agents are the compounds known for polycarbonate preparation having three or more functional groups, preferably those having three or more hydroxyl groups.
- Some of the useful compounds having three or more phenolic hydroxyl groups include, for example, phloroglucinol, 4,6-dimethyl-2,4,6-tri- (4-hydroxyphenyl) -heptene-2, 4,6-dimethyl-2,4,6- tri- (4-hydroxyphenyl) heptane, 1, 3, 5-tri- (4-hydroxyphenyl) -benzene, 1,1,1-tris (4-hydroxyphenyl) -ethane, tri- (4-hydroxyphenyl ) -phenylmethane, 2,2-bis (4,4-bis (4-hydroxyphenyl) -cyclohexyl] -propane, 2,4-bis (4-hydroxyphenyl-isopropyl) -phenol and tetra- (4 hydroxyphenyl) methane.
- trifunctional compounds are: 2,4-dihydroxybenzoic acid, trimesic acid, cyanuric chloride and 3,3-bis (3-methyl-4-hydroxyphenyl) -2-oxo-2,3-dihydroindole.
- Preferred branching agents are: 3,3-bis (3-methyl-4-hydroxyphenyl) -2-oxo-2,3-dihydroindole and 1,1,1-tri (4-hydroxyphenyl) -ethane.
- the branching agents are used in amounts of from 0.02 to 3.6 mol%, based on the Dihydroxyaryl- connection.
- the process for the production of polycarbonate by the transesterification process can be designed discontinuously or else continuously. After the dihydroxyaryl compounds and the diphenyl carbonate, optionally with other compounds, are in the form of a melt, the reaction is started in the presence of suitable catalysts. The conversion or the molecular weight is increased with increasing temperatures and falling pressures in suitable apparatuses and devices by removing the monohydroxyaryl compound which has split off until the desired final state has been reached.
- the loss rate of the diphenyl carbonate via the vapors and optionally added compounds such as, for example, a higher-boiling monohydroxyaryl compound, given by the choice of the method or plant for preparing the polycarbonate, the end groups are characterized in type and concentration.
- the temperatures over the entire process are 180 to 330 0 C, the pressures at 15 bar absolute to 0.01 mbar absolute.
- the continuous process for the preparation of polycarbonates is characterized in that one or more Dihydroxyaryl-16en with the diphenyl carbonate, optionally also other added reactants, using catalysts, after a precondensation without separating the Monohydroxyaryltagen formed in then then connected to several reaction evaporator Step by step increasing temperatures and gradually decreasing pressures, the molecular weight is built up to the desired size.
- the apparatus, apparatuses and reactors suitable for the individual reaction-evaporator stages are, according to the process course, heat exchangers, expansion apparatuses, separators, columns, evaporators, stirred vessels and reactors or other commercially available apparatuses which provide the necessary residence time at selected temperatures and pressures.
- the chosen devices must provide the necessary heat input and be designed to meet the ever-increasing melt viscosities.
- All devices are connected by pumps, piping and valves.
- the pipelines between all devices should, of course, be as short as possible and the curvatures of the lines should be kept as low as possible in order to avoid unnecessarily extended residence times.
- the external that is technical bist ⁇ conditions and concerns for assemblies of chemical plants to be considered.
- the reactants can either be melted together or the solid Dihydroxy ⁇ arylharm in the Diphenylcarbonatschmelze or the solid diphenyl carbonate in the melt the dihydroxyaryl compound are dissolved or both raw materials are melted together, preferably directly from the production.
- the residence times of the separate melts of the raw materials, in particular those of the melt of the dihydroxyaryl compound, are adjusted as short as possible.
- the melt mixture can linger longer due to the reduced melting point of the raw material mixture compared to the individual raw materials at correspondingly lower temperatures without sacrificing quality.
- the catalyst preferably dissolved in phenol, admixed and the melt is heated to the reaction temperature.
- This is at the beginning of the technically significant process for the production of polycarbonate from 2,2-bis (4-hydroxyphenyl) propane and diphenyl 180 to 220 0 C, preferably 190 to 210 ° C, most preferably 190 ° C.
- the reaction equilibrium is adjusted without the hydroxyaryl compound formed being removed.
- the reaction can be run at atmospheric pressure, but for technical reasons even at overpressure.
- the preferred pressure in technical systems is 2 to 15 bar absolute.
- the melt mixture is expanded in a first vacuum chamber whose pressure is set to 100 to 400 mbar, preferably to 150 to 300 mbar, and then directly heated to the inlet temperature in a suitable device at the same pressure.
- the resulting hydroxyaryl compound is evaporated with remaining monomers.
- the reaction mixture is in a second vacuum chamber whose pressure is 50 to 200 mbar, preferably 80 to 150 mbar, relaxed and then directly in a suitable Device at the same pressure to a temperature of 190 to 250 0 C, preferably 210 to 240 0 C, particularly preferably 210 to 230 0 C, heated.
- the resulting Hydroxyarylharm is evaporated with remaining monomers.
- the reaction mixture in a third vacuum chamber whose pressure is 30 to 150 mbar, preferably 50 to 120 mbar, relaxed and directly afterwards in a suitable device at the same pressure to a temperature of 220 to 280 0 C, preferably 240 to 270 0 C, particularly preferably 240 to 260 0 C, heated.
- the resulting HydroxyarylENS is evaporated with remaining monomers.
- the reaction mixture is in a further vacuum chamber whose pressure at 5 to 100 mbar, preferably 15 to 100 mbar, particularly preferably 20 to 80 mbar , relaxed and directly afterwards in a suitable device at the same pressure to a temperature of 250 to 300 0 C, preferably 260 to 290 ° C, particularly preferably 260 to 280 ° C, heated.
- a suitable device at the same pressure to a temperature of 250 to 300 0 C, preferably 260 to 290 ° C, particularly preferably 260 to 280 ° C, heated.
- Viscosity of the oligomeric carbonate is 1.04 to 1.20, preferably 1.05 to 1.15, particularly preferably 1.06 to 1.10.
- the oligocarbonate is required after a residence time of 5 to 20 minutes in a sump original, where appropriate with pumping at the same pressure and the same temperature as in the last flash / evaporator stage in a disk or basket reactor and at 250 to 310 0 C, preferred 250 to 290 0 C, more preferably 250 to 280 0 C, at pressures of 1 to 15 mbar, preferably 2 to 10 mbar, at residence times of 30 to 90 minutes, preferably 30 to 60 minutes, further condensed.
- the product achieves a relative viscosity of 1.12 to 1.28, preferably 1.13 to 1.26, particularly preferably 1.13 to 1.24.
- the melt leaving this reactor is brought to the desired final viscosity or the final molecular weight in a further disk or basket reactor.
- the temperatures are from 270 to 330 ° C., preferably from 280 to 320 ° C., particularly preferably from 280 to 310 ° C., the pressure from 0.01 to 3 mbar, preferably from 0.2 to 2 mbar, with residence times of from 60 to 180 min, preferably 75 to 150 min.
- the rel. Viscosities are adjusted to the level required for the intended application and are 1.18 to 1.40, preferably 1.18 to 1.36, more preferably 1.18 to 1.34.
- the function of the two basket reactors can also be summarized in a basket reactor.
- the vapors from all process stages are directly derived, collected and worked up. This work-up is usually carried out by distillation in order to achieve high purities of the recovered materials. This can be done, for example, according to DE-A 10 100 404. Recovery and isolation of the cleaved Monohydroxyarylharm in its purest form is of course from an economic and environmental point of view.
- the monohydroxyaryl compound can be used directly for producing a dihydroxyaryl compound or a diaryl carbonate.
- the disk or basket reactors are characterized by the fact that they provide a very large, constantly renewing surface on a vacuum at high residence times.
- the disk or basket reactors are geometrically formed according to the melt viscosities of the products. Suitable examples are reactors, as described in EP-A 1 253 163, or two-shaft reactors, as described in WO-A 99/28 370.
- oligocarbonates even very low molecular weight, and the finished polycarbonates are usually promoted by gear pumps, screws of various designs or positive displacement pumps special design.
- the polycarbonate obtained can be provided with other customary additives and additives (for example auxiliaries and reinforcing agents) to modify properties.
- additives and additives serves to prolong the service life (eg hydrolysis or degradation stabilizers), to improve the color stability (eg thermal and UV stabilizers), to simplify the processing (eg demulsifiers, flow aids), to improve the performance properties (eg antistatic agents), improving the flame retardancy, influencing the visual impression (eg organic colorants, pigments) or adapting the polymer properties to specific loads (impact modifiers, finely divided minerals, fibers, quartz powder, glass and carbon fibers).
- additives and additives can be added individually or in any desired mixtures or several different mixtures of the polymer melt, namely directly in the isolation of the polymer or after melting of granules in a so-called compounding step.
- the content of impurities is determined by gas chromatography (GC).
- GC gas chromatography
- the cool-on-column method is used for the determination of DPC and the phenol content.
- Metal determinations are carried out by ICP-OES (Inductively Coupled Plasma Optical Emission Spectroscopy).
- the content of phenolic OH is obtained by IR measurement.
- a difference measurement is measured from a solution of 2 g of polymer in 50 ml of dichloromethane over pure dichloromethane and determines the Absin difference at 3582 cmfl.
- the color number was determined as the difference of the extinction at 420 nm and 700 nm in dichloromethane at a concentration of 2.4 g / 50 ml and a layer thickness of 10 cm.
- Vacuum increased to 60 mbar and the temperature maintained for 15 minutes before being within
- the diphenyl carbonate used contained 0.5 ppm of phenyl salicylate, 0.5 ppm of o-phenoxybenzoic acid, 2 ppm of phenyl-o-phenoxybenzoate, 98 ppm of phenylpiperidinurethane, less than 1 ppm of phenyl chloroformate, 47 ppm of o-cresylphenyl carbonate and less than 1 ppm of chlorine.
- the apparatus was freed from atmospheric oxygen by applying a vacuum and purging with nitrogen (three times) and the mixture was melted at 150 ° C. The temperature was raised to 190 0 C and the resulting phenol distilled over 30 minutes. Then the pressure was regulated to 100 mbar and the resulting 20 minutes
- the melt was then passed through an expansion valve to a separator below 200 mbar.
- the effluent melt was in a, also below 200 mbar,
- Falling film evaporator heated again to 190 0 C and collected in a template. After a
- the conditions in the 2nd, 3rd and 4th stages were 100, 75 and 60 mbar; 220, 255 and 270 0 C as well as 20, 10 and 10 minutes.
- the resulting oligomer had a rel. Viscosity of 1.068. All vapors were passed through pressure controls in a column under vacuum and discharged as condensates.
- the oligomer was condensed in a downstream basket reactor at 280 0 C and 7.0 mbar at a residence time of 45 minutes to a higher molecular weight oligomer.
- the relative viscosity was 1.134.
- the vapors were condensed.
- the oligomer was condensed in a further basket reactor at 295 ° C and 1.3 mbar to a relative viscosity of 1.278.
- the average residence time was determined to be 130 minutes.
- the vapors are condensed behind or in the vacuum system.
- the total residence time was 274 minutes.
- Example 2 illustrates that a melt polycarbonate of excellent color can be obtained by the process of the present invention using the carbonate forming reagent.
- Example 3 shows that there are impurities which have no negative effect.
- the carbonate formation reagent containing a diphenyl carbonate used in the method of the present invention was analyzed for the content of impurities to obtain the results shown in Tables 2 and 3.
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Polyesters Or Polycarbonates (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE200410043114 DE102004043114A1 (de) | 2004-09-07 | 2004-09-07 | Verfahren zur Herstellung von Polycarbonat |
| DE102004043114.0 | 2004-09-07 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2006027110A1 true WO2006027110A1 (fr) | 2006-03-16 |
Family
ID=35134096
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/EP2005/009162 Ceased WO2006027110A1 (fr) | 2004-09-07 | 2005-08-25 | Procede de production de polycarbonate |
Country Status (2)
| Country | Link |
|---|---|
| DE (1) | DE102004043114A1 (fr) |
| WO (1) | WO2006027110A1 (fr) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1216982A2 (fr) * | 2000-12-19 | 2002-06-26 | Bayer Ag | Procédé de préparation d'esters diaryliques d'acide carbonique |
-
2004
- 2004-09-07 DE DE200410043114 patent/DE102004043114A1/de not_active Withdrawn
-
2005
- 2005-08-25 WO PCT/EP2005/009162 patent/WO2006027110A1/fr not_active Ceased
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1216982A2 (fr) * | 2000-12-19 | 2002-06-26 | Bayer Ag | Procédé de préparation d'esters diaryliques d'acide carbonique |
Also Published As
| Publication number | Publication date |
|---|---|
| DE102004043114A1 (de) | 2006-03-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1609818B1 (fr) | Compositions de polycarbonate stabilisées contre la chaleur | |
| EP2268706B1 (fr) | Polycarbonates à structures réarrangées, oligomères cycliques et linéaires et comportement d écoulement amélioré | |
| DE102007022130B4 (de) | Verfahren zur Herstellung von Polycarbonat nach dem Schmelzeumesterungsverfahren | |
| EP1742983B1 (fr) | Procede de preparation de polycarbonate | |
| EP2098553B1 (fr) | Procédé destiné à la fabrication de polycarbonate selon le procédé de surfaces de limite de phases | |
| DE102009032020A1 (de) | Verfahren zur Herstellung von Polycarbonat | |
| EP1216981B1 (fr) | Procédé continu de préparation d'esters diaryliques d'acide carbonique | |
| EP2090605B1 (fr) | Procédé de fabrication de polycarbonates | |
| EP1612231B1 (fr) | Inhibition d'impuretés de catalyseurs actives dans le procédé de transesterification de polycarbonate | |
| DE60010243T2 (de) | Verfahren und vorrichtung zur herstellung von monofonktionellen haloameisensäurearylestern | |
| DE60131898T2 (de) | Schmelzkatalysator-systeme für polycarbonate | |
| WO2006027110A1 (fr) | Procede de production de polycarbonate | |
| DE102008011903A1 (de) | Polycarbonate mit cyclischen Oligomeren und verbessertem Fließverhalten | |
| EP3097135A1 (fr) | Procédé de fabrication de polycarbonate selon le procédé d'interphase | |
| DE102004030664A1 (de) | Benzol- und Toluolsulfonsäureester als Additive in Polycarbonat | |
| EP1240232A1 (fr) | Procede pour la production de polycarbonate | |
| EP3728398B1 (fr) | Procédé de préparation d'un polycarbonate à l'aide d'un solvant organique à base d'hydrocarbures chlorés | |
| EP2343328B1 (fr) | Procédé et dispositif destinés à la fabrication de polycarbonate | |
| DE102004032125A1 (de) | Inhibierung von katalytisch aktiven Verunreinigungen in Polycarbonat nach dem Schmelzeumesterungsverfahren | |
| EP1565510A1 (fr) | Production de polycarbonate particulierement peu deteriore par l'oxygene | |
| DE102004057349A1 (de) | Benzol- und Toluolsulfonsäureester als Additive in Polycarbonat | |
| EP3851478A1 (fr) | Procédé de fabrication d'un polycarbonate à récupération améliorée des diarylcarbonate non réactif | |
| DE102004057348A1 (de) | Inhibrierung von katalytisch aktiven Verunreinigungen in Polycarbonat nach dem Schmelzeumesterungsverfahren |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KM KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NG NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW |
|
| AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU LV MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
| NENP | Non-entry into the national phase |
Ref country code: DE |
|
| 122 | Ep: pct application non-entry in european phase |