CN108948339B - Device and method for preparing aromatic polycarbonate - Google Patents
Device and method for preparing aromatic polycarbonate Download PDFInfo
- Publication number
- CN108948339B CN108948339B CN201810569597.XA CN201810569597A CN108948339B CN 108948339 B CN108948339 B CN 108948339B CN 201810569597 A CN201810569597 A CN 201810569597A CN 108948339 B CN108948339 B CN 108948339B
- Authority
- CN
- China
- Prior art keywords
- reactor
- polycondensation
- transesterification
- polycarbonate
- raw material
- 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.)
- Active
Links
Images
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
- C08G64/04—Aromatic polycarbonates
- C08G64/06—Aromatic polycarbonates not containing aliphatic unsaturation
-
- 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
Abstract
The present invention provides an apparatus and a method for preparing an aromatic polycarbonate, comprising: a raw material batching tank; the transesterification reactor is connected with the raw material batching tank; a prepolymerization reactor connected with the transesterification reactor; and the polycondensation reactor is connected with the prepolymerization reactor and is characterized in that the ester exchange reactor is a high-pressure ester exchange reactor. The ester exchange reaction of the invention adopts pressurization operation, which can effectively inhibit the generation of branched chain by-products, improve the molecular weight of the polycarbonate and obtain high-quality polycarbonate products.
Description
Technical Field
The invention belongs to the technical field of polycarbonate preparation, and particularly relates to a device and a method for preparing aromatic polycarbonate by an ester exchange polycondensation method.
Background
The polycarbonate is engineering plastic with excellent comprehensive performance and is characterized in that: has transparency, excellent impact strength, heat resistance, cold resistance, dimensional stability, electrical insulation and the like. The method is widely applied to the fields of industry, agriculture, IT and daily necessities.
Polycarbonate (commonly known as PC) is a polymer having a main chain containing carbonate bonds and benzene ring structures, and has a molecular structural formula:
wherein R is an aromatic arylene group or an aliphatic alkylene group.
A common aromatic polycarbonate, bisphenol a polycarbonate, has the formula:
the industrial production methods of aromatic polycarbonates include phosgene interfacial polycondensation and melt transesterification polycondensation. The melt transesterification polycondensation method is further classified into a conventional melt transesterification method and a non-phosgene melt transesterification polycondensation method. Both the phosgene interfacial polycondensation process and the conventional melt transesterification process require the use of highly toxic phosgene as the starting material. Due to the increasing environmental protection pressure and the stricter requirements on occupational safety and sanitation, the research and development and the industrial development of a non-phosgene molten ester exchange method in the industry are rapid in recent years.
According to the published reports at home and abroad, the non-phosgene melt transesterification polycondensation method adopts the transesterification of diphenyl carbonate and bisphenol A. Undoubtedly, the transesterification polycondensation technology used by different manufacturers has basically the same reaction principle, and all have certain differences in certain engineering designs and process conditions.
The reaction for the preparation of polycarbonate using bisphenol A (BPA) and diphenyl carbonate (DPC) is as follows:
first step of
Second step of
The non-phosgene melt transesterification polycondensation process can be divided into two steps. Firstly, bisphenol A (BPA) and diphenyl carbonate (DPC) are subjected to ester exchange reaction to remove phenol to produce oligomers; in the second step, polycondensation is completed at high temperature and under high vacuum. The conventional process route adopts the processing sequence of ester exchange, multistage pre-polycondensation and polycondensation, and simultaneously needs to strictly control the vacuum degree in the processes of ester exchange, pre-polycondensation and polycondensation to remove the generated phenol in time, but has the defect of more branched chain byproducts in the produced polycarbonate.
Disclosure of Invention
In view of the disadvantages of the prior art, the present invention is directed to an apparatus and a method for preparing an aromatic polycarbonate by an ester interchange polycondensation method, which can effectively suppress the generation of branched byproducts, increase the molecular weight of the polycarbonate, and obtain a high-quality polycarbonate product.
Specifically, the invention provides the following technical scheme:
an apparatus for preparing an aromatic polycarbonate, comprising: a raw material batching tank; the ester exchange reactor 3 is connected with the raw material batching tank; a prepolymerization reactor connected to the transesterification reactor 3; and a polycondensation reactor 6 connected to the prepolymerization reactor, wherein the transesterification reactor 3 is a high-pressure transesterification reactor.
Preferably, in the above device, the raw material batching tank is at least two parallel first raw material batching tank 1 and second raw material batching tank 2.
Preferably, in the above apparatus, the raw material batching tank is provided with a diphenyl carbonate feed inlet and a bisphenol a feed inlet, and the bisphenol a feed inlet is connected to the dryer.
Preferably, in the above device, a candle filter 9 is arranged between the transesterification reactor 3 and the prepolymerization reactor, and the filter element precision of the candle filter 9 is preferably 10-100 microns.
Preferably, in the above apparatus, the prepolymerization reactor comprises a first prepolymerization reactor 4 and a second prepolymerization reactor 5 connected in series.
Preferably, in the above apparatus, the raw material batching tank is provided with an exhaust port.
In the above apparatus, it is preferable that the transesterification reactor 3, the prepolymerization reactor and the polycondensation reactor 6 are provided with exhaust ports.
Preferably, in the above apparatus, the polycondensation reactor 6 is provided with at least one independent stirring shaft on the feeding side and the discharging side, and the stirring shaft is provided with a stirring paddle.
Preferably, in the above apparatus, the polycondensation reactor 6 is connected to a pelletizer 10.
Preferably, in the above device, the discharge port of the granulator 10 is connected to an electrostatic precipitator 11.
Preferably, in the above apparatus, a dynamic mixer 12 is provided between the polycondensation reactor 6 and the pelletizer 10, and an additive inlet is provided in the dynamic mixer 12.
A method for producing an aromatic polycarbonate using the apparatus as described in any of the above, comprising the steps of:
a material preparation process: uniformly mixing bisphenol A and molten dimethyl carbonate in a raw material batching tank;
an ester exchange process: performing transesterification on the mixed raw materials in the transesterification reactor 3;
pre-polycondensation: carrying out pre-polycondensation reaction on the product of the transesterification reaction in the pre-polymerization reactor;
a polycondensation step: and carrying out polycondensation reaction on the product of the pre-polycondensation reaction in the polycondensation reactor 6 to obtain a polycarbonate product.
Wherein, the pressure of the transesterification reaction is maintained at 200-1000KPa (A), preferably at 400-600KPa (A).
Preferably, in the above method, the bisphenol a is in a powder form, and is dried by the dryer and then enters the raw material batching tank.
In the above method, preferably, a transesterification catalyst is added in the transesterification step, and the transesterification catalyst is a nitrogen-containing basic compound, preferably tetramethylammonium hydroxide.
In another preferred scheme, an exhaust port is arranged on the raw material batching tank, the temperature of the raw material batching tank is maintained at 135-155 ℃, and an ester exchange catalyst is added in the batching process, wherein the ester exchange catalyst is a nitrogen-containing alkaline compound, preferably tetramethyl ammonium hydroxide.
Preferably, in any one of the above methods, a polycondensation catalyst is added in the polycondensation step, and the polycondensation catalyst is an acetylacetonato-based metal complex, preferably a lanthanide metal acetylacetonato compound.
Preferably, in any one of the above methods, the polycondensation reactor 6 is connected to a pelletizer 10, the discharge port of the pelletizer 10 is connected to an electrostatic precipitator 11, and the polycondensation process includes:
a granulation process: the polycarbonate melt obtained in the polycondensation step enters the granulator 10 for granulation, and a polycarbonate product with the required particle size is obtained as required;
a dust removal process: and the polycarbonate product obtained in the granulating procedure enters the electrostatic dust collector 11 for dust removal.
Preferably, in any one of the above methods, a dynamic mixer 12 is disposed between the polycondensation reactor 6 and the pelletizer 10, an additive inlet is disposed on the dynamic mixer 12, and the polycondensation step and the granulation step include:
an additive blending procedure: the polycarbonate obtained in the polycondensation step is fed into the dynamic mixer 12, mixed with additives, and then sent to the granulation step.
The invention has the beneficial effects that:
the invention provides a device and a method for preparing aromatic polycarbonate by an ester exchange polycondensation method, wherein an ester exchange reaction kettle is a high-pressure ester exchange reaction kettle, and the ester exchange reaction adopts pressurization operation, so that the generation of branched chain byproducts can be effectively inhibited, the molecular weight of the polycarbonate is improved, and a high-quality polycarbonate product is obtained.
Drawings
FIG. 1 is a flow chart of a process for producing an aromatic polycarbonate by an ester interchange polycondensation in example 1.
FIG. 2 is a flow chart of a process for producing an aromatic polycarbonate by an ester interchange polycondensation in example 2.
FIG. 3 is a flow chart of a process for producing an aromatic polycarbonate by an ester interchange polycondensation in example 3.
FIG. 4 is a flow chart of a process for producing an aromatic polycarbonate by an ester interchange polycondensation in example 4.
The designations in the figures illustrate the following: 1-first raw material batching tank, 2-second raw material batching tank, 3-ester exchange reaction kettle, 4-first prepolymerization reactor, 5-second prepolymerization reactor, 6-polycondensation reactor, 7-first dryer, 8-second dryer, 9-candle filter, 10-granulator and 11-electrostatic precipitator.
Detailed Description
The invention provides a device and a method for preparing aromatic polycarbonate by an ester exchange polycondensation method, aiming at solving the defect that the number of branched chain byproducts in the polycarbonate produced by the prior art is large.
In a preferred embodiment of the present invention, the present invention provides an apparatus for producing an aromatic polycarbonate, comprising: a raw material batching tank; the ester exchange reactor 3 is connected with the raw material batching tank; a prepolymerization reactor connected to the transesterification reactor 3; and a polycondensation reactor 6 connected to the prepolymerization reactor, wherein the transesterification reactor 3 is a high-pressure transesterification reactor.
In a preferred embodiment of the invention, the raw material batching tank is at least two parallel-connected primary raw material batching tank 1 and secondary raw material batching tank 2.
The raw materials proportioning tank adopts the multi-thread parallel operation mode, effectively reduces batching trouble probability of stopping, improves device operating stability.
In a preferred embodiment of the present invention, the raw material batching tank is provided with a diphenyl carbonate feeding port and a bisphenol a feeding port, and the bisphenol a feeding port is connected with the dryer.
In a preferred embodiment of the present invention, a candle filter 9 is arranged between the transesterification reactor 3 and the prepolymerization reactor, and the candle filter 9 preferably has a filter element precision of 10-100 microns.
The candle filter is used for filtering impurity particles and agglomerated particles in the materials and preventing the materials from continuously reacting to form high molecular impurities.
In a preferred embodiment of the present invention, the prepolymerization reactor comprises a first prepolymerization reactor 4 and a second prepolymerization reactor 5 connected in series.
In a preferred embodiment of the present invention, the raw material batching tank is provided with an air outlet.
In a preferred embodiment of the present invention, the transesterification reactor 3, the prepolymerization reactor and the polycondensation reactor 6 are provided with exhaust ports.
In a preferred embodiment of the present invention, the polycondensation reactor 6 is provided with at least one independent stirring shaft on the feed side and the discharge side, respectively, and the stirring shafts are provided with stirring paddles.
The differential stirring control is carried out on the materials with different viscosities at the feeding side and the discharging side, and more accurate reaction control can be realized on chain growth and molecular weight.
In a preferred embodiment of the invention, the polycondensation reactor 6 is connected to a pelletizer 10.
In a preferred embodiment of the present invention, the discharge port of the pelletizer 10 is connected to an electrostatic precipitator 11.
In a preferred embodiment of the present invention, a dynamic mixer 12 is disposed between the polycondensation reactor 6 and the pelletizer 10, and an additive inlet is disposed on the dynamic mixer 12.
The present invention also provides a preferred method for preparing an aromatic polycarbonate using the apparatus, comprising the steps of:
a material preparation process: uniformly mixing bisphenol A and molten dimethyl carbonate in a raw material batching tank;
an ester exchange process: performing transesterification on the mixed raw materials in the transesterification reactor 3;
pre-polycondensation: carrying out pre-polycondensation reaction on the product of the transesterification reaction in the pre-polymerization reactor;
a polycondensation step: and carrying out polycondensation reaction on the product of the pre-polycondensation reaction in the polycondensation reactor 6 to obtain a polycarbonate product.
Wherein, the pressure of the transesterification reaction is maintained at 200-1000KPa (A), preferably at 400-600KPa (A).
In a preferred embodiment of the present invention, the bisphenol a is in a powder form, and is dried by the dryer and then enters the raw material batching tank.
The bisphenol A powder is dried by nitrogen before being fed, the water content is controlled below 150ppm, the moisture carrying rate is effectively reduced, the oxidative discoloration of the material is reduced, and the product quality is improved.
In a preferred embodiment of the present invention, a transesterification catalyst is added to the transesterification step, and the transesterification catalyst is a nitrogen-containing basic compound, preferably tetramethylammonium hydroxide.
In another preferred embodiment of the present invention, the raw material batching tank is provided with an exhaust port, the temperature of the raw material batching tank is maintained at 135-155 ℃, and an ester exchange catalyst is added in the batching process, wherein the ester exchange catalyst is a nitrogen-containing basic compound, preferably tetramethyl ammonium hydroxide.
The transesterification catalyst is added in the batching procedure, meanwhile, the temperature of the raw material batching tank is maintained at 135-155 ℃, the transesterification pre-reaction at low temperature can be realized in the batching procedure, and the generated phenol is discharged through an exhaust port to promote the continuous proceeding of the reaction, thereby reducing the reaction residence time in the transesterification procedure and improving the conversion rate of the transesterification reaction.
In a preferred embodiment of the present invention, a polycondensation catalyst is added in the polycondensation step, and the polycondensation catalyst is an acetylacetone-based metal complex, preferably a lanthanide metal acetylacetone-based compound.
In a preferred embodiment of the present invention, the polycondensation reactor 6 is connected to a pelletizer 10, the discharge port of the pelletizer 10 is connected to an electrostatic precipitator 11, and the polycondensation process includes:
a granulation process: the polycarbonate melt obtained in the polycondensation step enters the granulator 10 for granulation, and a polycarbonate product with the required particle size is obtained as required;
a dust removal process: and the polycarbonate product obtained in the granulating procedure enters the electrostatic dust collector 11 for dust removal.
The granulated product particles can generate static electricity and dust in the conveying process, the electrostatic dust collector is arranged on the conveying pipeline, the static electricity of the product particles can be eliminated firstly, the dust on the surfaces of the product particles is removed through fed-back dry air, the dust content of the product particles is less than or equal to 300ppm, and a high-quality polycarbonate product is obtained.
In a preferred embodiment of the present invention, a dynamic mixer 12 is disposed between the polycondensation reactor 6 and the pelletizer 10, an additive inlet is disposed on the dynamic mixer 12, and the polycondensation process and the granulation process include:
an additive blending procedure: the polycarbonate obtained in the polycondensation step is fed into the dynamic mixer 12, mixed with additives, and then sent to the granulation step.
The aromatic bisphenol A polycarbonate prepared by the device and the method has the viscosity average molecular weight Mv of 20000-.
In order to facilitate understanding of the present invention, the apparatus and method for producing an aromatic polycarbonate according to the present invention will be further described with reference to the accompanying drawings and examples.
Example one
Referring to fig. 1, the present invention provides an apparatus for preparing an aromatic polycarbonate, which comprises: the device comprises a first raw material batching tank 1 and a second raw material batching tank 2 which are connected in parallel; the transesterification reactor 3 is connected with the first raw material batching tank 1 and the second raw material batching tank 2; a first prepolymerization reactor 4 and a second prepolymerization reactor 5 which are sequentially connected with the transesterification reactor 3; and a polycondensation reactor 6 connected to the second prepolymerization reactor 5, wherein the transesterification reactor 3 is a high-pressure transesterification reactor.
Wherein, be equipped with diphenyl carbonate feed inlet and bisphenol A feed inlet on the raw materials proportioning tank, the bisphenol A feed inlet and the first desicator 7 of first raw materials proportioning tank 1 are connected, the bisphenol A feed inlet and the second desicator 8 of second raw materials proportioning tank 2 are connected.
A candle filter 9 is arranged between the ester exchange reactor 3 and the prepolymerization reactor, and the filter element precision of the candle filter 9 is 40 micrometers.
Wherein, the ester exchange reactor 3, the first pre-polymerization reactor 4, the second pre-polymerization reactor 5 and the polycondensation reactor 6 are all provided with exhaust ports.
Wherein, the polycondensation reactor 6 is connected with a granulator 10.
Wherein, the discharge hole of the granulator 10 is connected with an electrostatic dust collector 11.
Wherein, be equipped with dynamic mixer 12 between polycondensation reactor 6 and pelleter 10, be equipped with the additive entry on the dynamic mixer 12.
The process for producing an aromatic polycarbonate by using the above-mentioned apparatus is specifically described below, and specifically comprises the steps of:
a material mixing procedure: after being unpacked and metered, the bisphenol A solid powder enters a first dryer 7 and a second dryer 8, moisture and air carried by bisphenol A solid are sufficiently removed by using dry nitrogen, and then the bisphenol A solid powder and molten diphenyl carbonate are mixed in a ratio of 1: 1.06 mol ratio is introduced into the first raw material batching tank 1 and the second raw material batching tank 2 to be stirred and mixed evenly.
An ester exchange process: the mixed raw materials are sent into a transesterification reactor 3 through a fluid pump for carrying out the transesterification reaction, and simultaneously, a transesterification catalyst tetramethyl ammonium hydroxide is added, wherein the adding amount of the catalyst is 2 multiplied by 10-6mol/mol BPA. The temperature of the ester exchange reactor 3 is maintained at 160 ℃ in 130-.
Pre-polycondensation: the melt material in the ester exchange reactor 3 flows automatically through the candle filter 9 and enters the first pre-polymerization reactor 4 under the action of pressure difference. The temperature of the first prepolymerization reactor 4 is maintained at 190 ℃ to 210 ℃, the reaction pressure is maintained at 20-35KPa (A) by a vacuum system connected with an exhaust port, and the generated phenol is discharged from the exhaust port. The melt material in the first pre-polymerization reactor 4 is pumped to the second pre-polymerization reactor 5 by a fluid pump, the temperature of the second pre-polymerization reactor 5 is maintained at 240-270 ℃, the reaction pressure is maintained at 3-8KPa (A) by a vacuum system connected with an exhaust port, and the generated phenol is discharged from the exhaust port.
A polycondensation step: the melt material in the second prepolymerization reactor 5 is pumped to a polycondensation reactor 6 by a fluid pump, and a polycondensation catalyst cerium acetylacetonate is added at the same time, wherein the addition amount of the catalyst is 5 multiplied by 10-6mol/mol BPA. The temperature of the polycondensation reactor 6 is maintained at 270 ℃ and 295 ℃, the reaction pressure is maintained at 0.1-1.5KPa (A) through a vacuum system connected with an exhaust port, and the generated phenol is discharged from the exhaust port.
An additive blending procedure: the polycarbonate obtained in the polycondensation step is introduced into the dynamic mixer 12 and mixed with additives. In this example, the additive was BASF antioxidant rganox1076 added in an amount of 1500 ppm.
A granulation process: the polycarbonate obtained in the additive blending procedure is sent to a granulator 10 through a fluid pump for granulation, and a polycarbonate product with the required particle size is obtained according to the requirement.
A dust removal process: and the polycarbonate product obtained in the granulating procedure enters the electrostatic dust collector 11 for dust removal and then is sent out for packaging.
Example two
As shown in fig. 2, the second embodiment is different from the first embodiment in the polycondensation step: the polycondensation reactor of the second embodiment is a biaxial polycondensation reactor, and the feed side and the discharge side are respectively provided with an independent stirring shaft, the stirring shaft is provided with stirring paddles, the stirring speed of the feed side is 10rpm, and the stirring speed of the discharge side is 6 rpm.
EXAMPLE III
As shown in fig. 3, the difference between the third embodiment and the first embodiment is that the batching process is different: the first raw material batch tank 1 and the second raw material batch tank 2 of the third example were provided with exhaust ports, and the transesterification catalyst tetramethylammonium hydroxide was added to the raw material batch tanks 1 and 2 in an amount of 2X 10-6mol/mol BPA. The temperature is maintained at 135-155 ℃, the pressure is maintained at 75-90KPa (A) by a vacuum system connected with an exhaust port, the raw materials undergo transesterification pre-reaction in the batching process, and the generated phenol is discharged from the exhaust port.
Example four
As shown in fig. 4, the fourth example is different from the first example in the compounding step and the polycondensation step: (1) the first raw material batch tank 1 and the second raw material batch tank 2 of the fourth example were equipped with an exhaust port, and the transesterification catalyst tetramethylammonium hydroxide was added to the raw material batch tanks 1 and 2 in an amount of 2X 10-6mol/mol BPA. The temperature is maintained at 135-155 ℃, the pressure of a vacuum system connected with an exhaust port is maintained at 75-90KPa (A), the raw materials undergo transesterification pre-reaction in the burdening process, and the generated phenol is exhausted from the exhaust portAnd discharging from the outlet. (2) The polycondensation reactor of the fourth embodiment is a biaxial polycondensation reactor, and the feed side and the discharge side are respectively provided with an independent stirring shaft on which stirring paddles are mounted, the stirring speed at the feed side is 10rpm, and the stirring speed at the discharge side is 6 rpm.
Comparative example 1
The difference between the first comparative example and the first example is that the transesterification process is different: comparative example-A transesterification was carried out under a vacuum, the pressure of the transesterification was maintained at 60 to 70KPa (A) by a vacuum system connected to an exhaust port, and the produced phenol was discharged from the exhaust port.
In the above examples, the physical properties of the obtained polycarbonate were measured by the following methods:
viscosity average molecular weight Mv, weight average molecular weight Mw: polycarbonate samples were analyzed by GPC chromatography using chloroform as the solvent at room temperature, and the calibration parameter K was 14.1000 and α was 0.7000.
Content of branched matter: hydrolyzing a polycarbonate sample under alkaline conditions, and performing high performance chromatography analysis on the hydrolysate (shown as formula 1) by using an HPLC chromatograph to determine the content of the branched substances.
Melt index: the measurement is carried out by a melt flow rate meter, and the required data are measured after the polycarbonate sample is heated to 300 ℃ according to the mass method in GB/T3682 or ISO 3311.
Hue index: the absorbance A of polycarbonate in methylene chloride (1g/10mL) was measured at a wavelength of 380nm and an absorption cell length of 10nm using a Hitachi UV-160A UV spectrophotometer380Deducting its absorbance A at 580nm580The degree of coloration of the polycarbonate was evaluated, namely: hue index ═ A380-A580。
The experiments of examples 1 to 4 and comparative example 1 described above were each carried out 3 times to determine the average value of each index of the product, as specifically shown in table 1. Table 1 shows the results of measurements of the production cycle of the apparatus, the energy consumption of the product, and various physical indicators (viscosity-average molecular weight, weight-average molecular weight, content of branched substances, melt index, Hue index) of the product in examples 1 to 4 and comparative example 1.
TABLE 1
As is apparent from Table 1, (1) when the transesterification reactor of example 1 of the present invention is a high-pressure reactor, and the transesterification reaction is conducted under pressure, the content of the branched materials in the product is remarkably reduced, and the viscosity-average molecular weight and the weight-average molecular weight of the polycarbonate are increased, as compared with those of comparative example 1. (2) Example 2 a polycondensation reactor was optimized on the basis of example 1 to be a biaxial polycondensation reactor, and by controlling the differential stirring of materials having different viscosities on the feed side and the discharge side, the content of branched materials was further reduced and the viscosity-average molecular weight and the weight-average molecular weight were slightly increased. (3) Example 3 the batching process is optimized on the basis of example 1, and the raw materials undergo transesterification pre-reaction in the batching process, so that the production period of the device is shortened. (4) Example 4 is based on example 1, optimize both the polycondensation reactor for the biaxial reactor and the batching process so that the raw materials have transesterification reaction in the batching process, although the reaction period is not shortened compared with example 3, the reaction period is shortened compared with example 2, the content of the branched substance is greatly reduced, and the viscosity-average molecular weight and the weight-average molecular weight of the polycarbonate are improved.
Finally, it is noted that the above-mentioned preferred embodiments illustrate rather than limit the invention, and that, although the invention has been described in detail with reference to the above-mentioned preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the scope of the invention as defined by the appended claims.
Claims (17)
1. A method for preparing an aromatic polycarbonate using an apparatus for preparing an aromatic polycarbonate, wherein the apparatus comprises: a raw material batching tank; the ester exchange reactor (3) is connected with the raw material batching tank; a prepolymerization reactor connected with the transesterification reactor (3); a polycondensation reactor (6) connected to the prepolymerization reactor, characterized in that the transesterification reactor (3) is a high pressure transesterification reactor; the raw material batching tank is provided with a diphenyl carbonate feeding port and a bisphenol A feeding port, and the bisphenol A feeding port is connected with the dryer; the ester exchange reactor (3), the pre-polymerization reactor and the polycondensation reactor (6) are all provided with exhaust ports; the polycondensation reactor (6) is provided with at least one independent stirring shaft on the feeding side and the discharging side respectively, and stirring paddles are arranged on the stirring shafts; the polycondensation reactor (6) is connected with a granulator (10), and a discharge hole of the granulator (10) is connected with an electrostatic dust collector (11); the temperature of the ester exchange reactor is maintained at 160 ℃ under 130 ℃ and 600KPa (A) under 400 ℃ by introducing high-pressure nitrogen, and the generated phenol is discharged from the exhaust port by nitrogen replacement;
the method comprises the following steps:
a material preparation process: uniformly mixing bisphenol A and molten dimethyl carbonate in a raw material batching tank;
an ester exchange process: carrying out transesterification reaction on the mixed raw materials in the transesterification reactor (3);
pre-polycondensation: carrying out pre-polycondensation reaction on the product of the transesterification reaction in the pre-polymerization reactor;
a polycondensation step: carrying out polycondensation reaction on the product of the pre-polycondensation reaction in the polycondensation reactor (6) to obtain a polycarbonate product;
the raw material batching tank is provided with an exhaust port, the temperature of the raw material batching tank is maintained at 135-155 ℃, and an ester exchange catalyst is added in the batching process, wherein the ester exchange catalyst is a nitrogen-containing alkaline compound.
2. The method according to claim 1, wherein the raw material dosing tank is at least two parallel connected primary (1) and secondary (2) raw material dosing tanks.
3. The process according to claim 1, wherein a candle filter (9) is provided between the transesterification reactor (3) and the prepolymerization reactor.
4. The process according to claim 2, wherein a candle filter (9) is provided between the transesterification reactor (3) and the prepolymerization reactor.
5. The method according to claim 4, wherein the candle filter (9) cartridge precision is 10-100 microns.
6. The process according to claim 1, wherein the prepolymerization reactor comprises a first prepolymerization reactor (4) and a second prepolymerization reactor (5) connected in series.
7. The process according to claim 4, wherein the prepolymerization reactor comprises a first prepolymerization reactor (4) and a second prepolymerization reactor (5) connected in series.
8. The method of any one of claims 1-7, wherein said bisphenol A is in powder form and is dried by said dryer before entering said raw material batching tank.
9. The method according to any one of claims 1 to 7, wherein a transesterification catalyst is added in the transesterification step, and the transesterification catalyst is a nitrogen-containing basic compound.
10. The process of claim 9, wherein the transesterification catalyst is tetramethylammonium hydroxide.
11. The process of any of claims 1-7, wherein the transesterification catalyst is tetramethylammonium hydroxide.
12. The method of any of claims 1-7, wherein a polycondensation catalyst is added during the polycondensation process, the polycondensation catalyst being an acetylacetonato-based metal complex.
13. The process of claim 12, wherein the polycondensation catalyst is a lanthanide metal acetylacetonate-based compound.
14. The method according to any one of claims 1 to 7, wherein the polycondensation reactor (6) is connected with a pelletizer (10), the discharge port of the pelletizer (10) is connected with an electrostatic precipitator (11), and the polycondensation process is followed by:
a granulation process: the polycarbonate obtained in the polycondensation step enters the granulator (10) for granulation, and a polycarbonate product with the required particle size is obtained according to the requirement;
a dust removal process: and the polycarbonate product obtained in the granulating procedure enters the electrostatic dust collector (11) for dust collection.
15. The method according to claim 8, wherein the polycondensation reactor (6) is connected with a pelletizer (10), the discharge port of the pelletizer (10) is connected with an electrostatic precipitator (11), and the polycondensation process is followed by:
a granulation process: the polycarbonate obtained in the polycondensation step enters the granulator (10) for granulation, and a polycarbonate product with the required particle size is obtained according to the requirement;
a dust removal process: and the polycarbonate product obtained in the granulating procedure enters the electrostatic dust collector (11) for dust collection.
16. The method according to claim 9, wherein the polycondensation reactor (6) is connected with a pelletizer (10), the discharge port of the pelletizer (10) is connected with an electrostatic precipitator (11), and the polycondensation process is followed by:
a granulation process: the polycarbonate obtained in the polycondensation step enters the granulator (10) for granulation, and a polycarbonate product with the required particle size is obtained according to the requirement;
a dust removal process: and the polycarbonate product obtained in the granulating procedure enters the electrostatic dust collector (11) for dust collection.
17. The method according to claim 12, wherein the polycondensation reactor (6) is connected with a pelletizer (10), the discharge port of the pelletizer (10) is connected with an electrostatic precipitator (11), and the polycondensation process is followed by:
a granulation process: the polycarbonate obtained in the polycondensation step enters the granulator (10) for granulation, and a polycarbonate product with the required particle size is obtained according to the requirement;
a dust removal process: and the polycarbonate product obtained in the granulating procedure enters the electrostatic dust collector (11) for dust collection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810569597.XA CN108948339B (en) | 2018-06-05 | 2018-06-05 | Device and method for preparing aromatic polycarbonate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810569597.XA CN108948339B (en) | 2018-06-05 | 2018-06-05 | Device and method for preparing aromatic polycarbonate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108948339A CN108948339A (en) | 2018-12-07 |
| CN108948339B true CN108948339B (en) | 2021-04-06 |
Family
ID=64493666
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810569597.XA Active CN108948339B (en) | 2018-06-05 | 2018-06-05 | Device and method for preparing aromatic polycarbonate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108948339B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105175703A (en) * | 2015-10-15 | 2015-12-23 | 宁波浙铁大风化工有限公司 | Equipment for preparing polycarbonate |
| CN106622083A (en) * | 2016-12-23 | 2017-05-10 | 南京昊扬化工装备有限公司 | Novel high-viscosity final polycondensation reactor |
| DE102016119477A1 (en) * | 2016-10-12 | 2018-04-12 | Epc Engineering Consulting Gmbh | Catalyst System |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0827265A (en) * | 1994-07-20 | 1996-01-30 | Mitsubishi Chem Corp | Production of aromatic polycarbonate |
| CN106985300B (en) * | 2017-04-24 | 2019-04-05 | 宁波浙铁大风化工有限公司 | A kind of polycarbonate preparation system |
-
2018
- 2018-06-05 CN CN201810569597.XA patent/CN108948339B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105175703A (en) * | 2015-10-15 | 2015-12-23 | 宁波浙铁大风化工有限公司 | Equipment for preparing polycarbonate |
| DE102016119477A1 (en) * | 2016-10-12 | 2018-04-12 | Epc Engineering Consulting Gmbh | Catalyst System |
| CN106622083A (en) * | 2016-12-23 | 2017-05-10 | 南京昊扬化工装备有限公司 | Novel high-viscosity final polycondensation reactor |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108948339A (en) | 2018-12-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6616894B2 (en) | Economical process for producing a resin composition comprising a polyalkylene carbonate having improved thermal stability and processability | |
| US6436326B1 (en) | Forming slurry of reactive components and continuously feeding into continuous reactor | |
| KR101913449B1 (en) | Method for producing polycarbonate, and polycarbonaet pellets | |
| JP2018531314A6 (en) | Economical process for producing a resin composition comprising a polyalkylene carbonate having improved thermal stability and processability | |
| KR102352612B1 (en) | Methods, apparatus and uses for substantially reprocessing polyalkylene terephthalates | |
| CN111849026A (en) | Method and system for producing rPET bottle grade polyester chip | |
| CN108948339B (en) | Device and method for preparing aromatic polycarbonate | |
| EP1425337B1 (en) | Method for recycling polycarbonates | |
| CN108948340B (en) | Device and method for preparing aromatic polycarbonate | |
| CN108948341B (en) | Device and method for preparing aromatic polycarbonate | |
| CN108727579B (en) | Device and method for preparing aromatic polycarbonate | |
| CN111205235B (en) | Preparation method for continuously and stably producing highly etherified hexamethoxy methyl melamine | |
| CN109456470B (en) | System and method for preparing polyethylene terephthalate for optical film | |
| CN105175706A (en) | High-light-permeability panlite and production method thereof | |
| CN112724609B (en) | Hydrolysis-resistant polyester and preparation method thereof | |
| CN111269372B (en) | Method for preparing hexamethylol melamine with continuous and stable quality | |
| CN109294198B (en) | Preparation method and application of transparent high-temperature-resistant polyarylate/polycarbonate alloy ester exchange reaction inhibitor | |
| US10000586B2 (en) | Method for producing polyvinyl alcohol | |
| US5973104A (en) | High molecular polyetherpolyester and its production process and use | |
| JP2010083957A (en) | Method for production of polybutylene terephthalate | |
| CN110964190B (en) | Raw material conveying and blending device used in polycarbonate synthesis process | |
| JP4169868B2 (en) | Polyoxymethylene copolymer and process for producing the same | |
| KR20240036576A (en) | Method for producing polysiloxane-polycarbonate block copolymer | |
| CN101121782A (en) | Neutralization treatment method for catalyst used for preparing polycarbonate from aromatics dihydroxy compounds and diester carbonate, and neutralizing agent used for the same | |
| JP2003201343A (en) | Method for producing aromatic polycarbonate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20210715 Address after: 324012 Building 1, 27 Dujuan Road, Quzhou City, Zhejiang Province Patentee after: TOpen Technology (Quzhou) Co.,Ltd. Address before: Room 518-10, Yintian building, Ningbo Free Trade Zone, Zhejiang 315899 Patentee before: ZHEJIANG POLYCARBON ENGINEERING TECHNOLOGY Co.,Ltd. |
|
| TR01 | Transfer of patent right |