CN113801313B - Preparation method of high molecular weight polycarbonate and polycarbonate - Google Patents
Preparation method of high molecular weight polycarbonate and polycarbonate Download PDFInfo
- Publication number
- CN113801313B CN113801313B CN202111109227.6A CN202111109227A CN113801313B CN 113801313 B CN113801313 B CN 113801313B CN 202111109227 A CN202111109227 A CN 202111109227A CN 113801313 B CN113801313 B CN 113801313B
- Authority
- CN
- China
- Prior art keywords
- molecular weight
- transesterification
- polycarbonate
- temperature
- tower
- 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
- C08G64/20—General preparatory processes
- C08G64/30—General preparatory processes using carbonates
- C08G64/307—General preparatory processes using carbonates and phenols
-
- 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
- C08G64/305—General preparatory processes using carbonates and alcohols
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)
Abstract
The application relates to the technical field of polycarbonate, in particular to a preparation method of high molecular weight polycarbonate and polycarbonate. The preparation method of the high molecular weight polycarbonate comprises the steps of taking carbonic diester and dihydroxyl compound as raw materials, adding a catalyst, mixing and preheating, and sequentially carrying out transesterification, pre-polycondensation and final polycondensation under the conditions that the temperature is 210-320 ℃ and the absolute pressure is 0.01-30 kPa; the transesterification adopts at least three tower transesterification reactors which are connected in sequence, the temperature of the three tower transesterification reactors is gradually increased, the temperature of the three tower transesterification reactors is 210-240 ℃, the temperature of the three tower transesterification reactors is 230-250 ℃ and the temperature of the three tower transesterification reactors is 245-270 ℃, the pre-polycondensation adopts at least one horizontal pre-polycondensation reactor, and the final polycondensation adopts at least one horizontal final polycondensation reactor. The polycarbonate prepared by the method has narrower molecular weight distribution, the average molecular weight can reach 4w, and the polycarbonate has higher molecular weight.
Description
Technical Field
The present application relates to the field of polycarbonate technology, and more particularly, to a method for preparing a high molecular weight polycarbonate and a polycarbonate.
Background
Polycarbonates (abbreviated as PC) are high-molecular polymers containing carbonate groups in the molecular chain, and are classified into various types such as aliphatic, aromatic, aliphatic-aromatic, etc., depending on the structure of the ester groups. Among them, aliphatic and aromatic polycarbonates have excellent mechanical properties and are widely used in the fields of electronic parts, automobile parts, optical recording media, lenses, and the like.
The molecular weight and the distribution thereof are one of important parameters for characterizing the high polymer, and have important influences on the mechanical property, the thermal stability and the like of the high polymer. The existing polycarbonate is generally synthesized by transesterification and polycondensation reaction of bisphenol A and diphenyl carbonate, however, the molecular weight distribution of the polycarbonate prepared at home at present is wider, and the maximum average molecular weight is only about 3 w.
With respect to the above technical scheme, the inventor considers how to effectively prepare polycarbonate with higher average molecular weight, which is a technical problem to be solved urgently at present.
Disclosure of Invention
In order to obtain a polycarbonate with a higher average molecular weight, the present application provides a method for preparing a high molecular weight polycarbonate and a polycarbonate.
In a first aspect, the present application provides a method for preparing a high molecular weight polycarbonate, which adopts the following technical scheme:
a preparation method of high molecular weight polycarbonate, take carbonic diester and dihydroxyl compound as raw materials, mix and preheat after adding catalyst, carry on transesterification, pre-polycondensation and final polycondensation reaction sequentially under the conditions that the temperature is 210-320 deg.C and absolute pressure is 0.01-30 kPa;
the transesterification adopts at least three tower transesterification reactors which are connected in sequence, the temperature of the three tower transesterification reactors is gradually increased, the temperature of the three tower transesterification reactors is 210-240 ℃, the temperature of the three tower transesterification reactors is 230-250 ℃ and the temperature of the three tower transesterification reactors is 245-270 ℃, the pre-polycondensation adopts at least one horizontal pre-polycondensation reactor, and the final polycondensation adopts at least one horizontal final polycondensation reactor.
By adopting the technical scheme, the inventor finds that the viscosity of the materials is continuously increased along with the progress of the transesterification reaction, and the mass transfer and the heat transfer become more and more difficult, so that the side reactions such as local overheating, easy generation of branching, crosslinking and the like are caused; therefore, the method sets at least three tower type transesterification reactors, materials need to be conveyed regularly, local overheating of the materials is avoided, and the gradual rising temperature is utilized, so that the transesterification reaction is performed smoothly, and side reactions such as branching, crosslinking and the like are reduced; on the basis, the precondensation reactor and the final polycondensation reactor of the method adopt horizontal structures, compared with a tower structure, the temperature difference between the circumference and the center of the reactor can be obviously reduced, so that the molecular weight distribution of the polycarbonate prepared by the method is narrower, the average molecular weight can reach 4w, and the polycarbonate has higher molecular weight.
Preferably, the carbonic acid diester has the structural formula
Wherein R is alkyl or aryl.
By adopting the technical scheme, the carbonic acid diester with the structural formula, such as diphenyl carbonate, dimethyl carbonate, diethyl carbonate and the like, can be singly used or can be mixed for use to prepare the polycarbonate with high molecular weight.
Preferably, the structural formula of the dihydroxyl compound is HO-R-OH, wherein R is alkyl or aryl.
By adopting the above technical scheme, the dihydroxy compound of the above structural formula, for example, aliphatic dihydroxy compounds such as ethylene glycol, 1, 2-propylene glycol, 1, 3-propylene glycol, 1, 2-butanediol, 1, 3-butanediol, 1, 4-butanediol, 1, 5-heptanediol, 1, 6-hexanediol, etc., aromatic dihydroxy compounds such as 2, 2-bis (4-hydroxyphenyl) propane (bisphenol A, abbreviated as BPA), 2-bis (4-hydroxy-3, 5-dimethylphenyl) propane, 2-bis (4-hydroxy-3, 5-diethylphenyl) propane, 2-bis (4-hydroxy- (3, 5-diphenyl) phenyl) propane, 2-bis (4-hydroxy-3, 5-dibromophenyl) propane, etc., can be selected for the preparation of polycarbonates of high molecular weight.
Preferably, the catalyst is an alkali metal bicarbonate.
Preferably, the alkali metal bicarbonate is potassium bicarbonate.
By adopting the technical scheme, the raw materials are easy to deteriorate under the acidic condition, and the alkali metal bicarbonate is adopted, so that on one hand, the whole alkalinity of the materials can be ensured, and on the other hand, the raw materials are promoted to effectively synthesize the polycarbonate with high molecular weight; wherein, in the catalysis process, the alkali metal bicarbonate has relatively weak early alkalinity, can promote the raw materials to slowly perform transesterification reaction, and reduces side reactions such as branching, crosslinking and the like; as the temperature of the material increases, the alkali metal bicarbonate is heated and decomposed into alkali metal carbonate, so that the alkalinity of the material is enhanced, the catalysis of the material to the material is also enhanced, and polycarbonate with narrower molecular weight distribution can be obtained; among them, alkali metal hydrogencarbonates may be sodium hydrogencarbonate, potassium hydrogencarbonate, lithium hydrogencarbonate, cesium hydrogencarbonate and the like, and among them, the reaction process of potassium hydrogencarbonate is more easily controlled, and the stability after quenching of the potassium salt catalyst is high, and thus the average molecular weight of the produced polycarbonate is maximum and the weather resistance is more excellent, and therefore it is further preferable.
Preferably, the carbonic acid diester, the dihydroxy compound and the catalyst are mixed and preheated for 2-3 hours at a temperature of 80-100 ℃.
By adopting the technical scheme, the potassium bicarbonate can still keep good stability at 80-100 ℃, and the carbonic diester and the dihydroxyl compound at the temperature have good fluidity, so that the materials are fully and uniformly mixed, and the preparation is made for transesterification.
Preferably, the mixing preheating adopts at least two mixing tanks, each mixing tank is provided with a heat tracing device, the heat tracing device comprises a large jacket sleeve and a small jacket sleeve, and one small jacket sleeve is clamped between every two large jacket sleeves.
By adopting the technical scheme, the material mixing device adopts at least two material mixing tanks, so that materials are mixed in small batches, and each material can be quickly and uniformly mixed; the application still adopts big, little double-layered sleeve pipe for heat tracing device fully contacts with the blending tank, and then effectively improves thermal conduction efficiency, reduces the loss of energy, promotes the material in the blending tank to heat up to the settlement temperature fast.
Preferably, the first tower transesterification reactor is externally connected with a catalyst storage tank.
By adopting the technical scheme, the catalyst can be directly supplemented in the first tower type transesterification reactor, so that the materials are ensured to contain enough catalyst.
Preferably, the tower type transesterification reactor is sequentially externally connected with a phenol purification tower and a carbonic acid diester purification tower, and the gas pumped from the tower type transesterification reactor is treated by the phenol purification tower and then is introduced into the carbonic acid diester purification tower.
By adopting the technical scheme, if the tail gas generated by the reaction of the carbonic acid diester and the dihydroxyl compound contains phenol, the phenol can be effectively recovered by the phenol purification tower, so that the transesterification reaction is carried out forward to obtain the polycarbonate with high average molecular weight, and the phenol obtained by purification can be used as a byproduct, thereby increasing the additional benefit for preparing the polycarbonate; in addition, the carbonic acid diester is usually added in excess during the reaction to ensure that the dihydroxy compound is completely reacted, so that the carbonic acid diester purifying column can separate the excess carbonic acid diester, thereby reducing the loss rate of the raw material.
In a second aspect, the present application provides a polycarbonate, using the following technical scheme:
a polycarbonate prepared by the above preparation method. The average molecular weight of the polycarbonate can reach 4w, and the polycarbonate has narrower molecular weight distribution, so that the polycarbonate has more excellent mechanical property and thermal stability.
In summary, the present application has the following beneficial effects:
1. the preparation method can avoid local overheating of materials, so that transesterification reaction is performed smoothly, side reactions such as branching and crosslinking are reduced, the molecular weight of the polycarbonate prepared by the method is distributed uniformly, the average molecular weight can reach 4w, and the polycarbonate has higher molecular weight.
2. In the method, alkali metal bicarbonate is used as a catalyst, and the specific temperature is used for preheating, so that the catalysis effect is changed from weak to strong along with the temperature, the raw materials can be orderly subjected to transesterification and polymerization, and side reactions such as branching and crosslinking are reduced, so that the polycarbonate with higher average molecular weight and narrower molecular weight distribution is obtained.
Drawings
FIG. 1 is a diagram of a system for preparing a polycarbonate according to the present application.
Reference numerals illustrate:
1. a carbonic acid diester storage tank; 2. a dihydroxy compound storage tank; 3. a catalyst storage tank; 4. a mixing tank; 5. a column transesterification reactor; 6. a phenol purification column; 7. a carbonic acid diester purification column; 8. a vacuum pump; 9. a tower pre-polycondensation reactor; 10. a horizontal precondensation reactor; 11. a horizontal final polycondensation reactor; 12. an extruder; 13. a granulator; 15. a screen changer; 16. butterfly filters; 17. a spray cooler; 18. a heater.
Detailed Description
The present application is described in further detail below with reference to the accompanying drawings, examples and comparative examples, wherein the raw materials and reagents are commercially available products.
Examples
The high molecular weight polycarbonate uses carbonic diester and dihydroxyl compound as raw materials, and is mixed and preheated after adding a catalyst, and transesterification, pre-polycondensation and final polycondensation are sequentially carried out under the conditions that the temperature is 210-320 ℃ and the absolute pressure is 0.01-30 kPa.
Wherein the preferred structural formula is
Wherein R is alkyl or aryl. The carbonic acid diester of the structural formula, such as diphenyl carbonate, dimethyl carbonate, diethyl carbonate, etc., may be used singly or in combination of two or more, to prepare a polycarbonate of high molecular weight.
Preferred dihydroxy compounds of the formula HO-R-OH are those wherein R is alkyl or aryl. The dihydroxy compound of the formula (I) is, for example, an aliphatic dihydroxy compound such as ethylene glycol, 1, 2-propylene glycol, 1, 3-propylene glycol, 1, 2-butanediol, 1, 3-butanediol, 1, 4-butanediol, 1, 5-heptanediol, 1, 6-hexanediol, or an aromatic dihydroxy compound such as 2, 2-bis (4-hydroxyphenyl) propane (bisphenol A, abbreviated as BPA), 2-bis (4-hydroxy-3, 5-dimethylphenyl) propane, 2-bis (4-hydroxy-3, 5-diethylphenyl) propane, 2-bis (4-hydroxy- (3, 5-diphenyl) phenyl) propane, or 2, 2-bis (4-hydroxy-3, 5-dibromophenyl) propane, which can be used for the production of a high molecular weight polycarbonate.
Because the raw materials are easy to deteriorate under the acidic condition, the catalyst adopts alkali metal bicarbonate, so that on one hand, the whole alkalinity of the materials can be ensured, and on the other hand, the raw materials are promoted to effectively synthesize the polycarbonate with high molecular weight. Wherein, in the catalysis process, the alkali metal bicarbonate has relatively weak early alkalinity, can promote the raw materials to slowly perform transesterification reaction, and reduces side reactions such as branching, crosslinking and the like; as the temperature of the material increases, the alkali metal bicarbonate is heated and decomposed into alkali metal carbonate, so that the alkalinity of the material is enhanced, the catalysis of the material to the material is also enhanced, and polycarbonate with narrower molecular weight distribution can be obtained; among them, alkali metal hydrogencarbonates may be sodium hydrogencarbonate, potassium hydrogencarbonate, lithium hydrogencarbonate, cesium hydrogencarbonate and the like, and among them, the reaction process of potassium hydrogencarbonate is more easily controlled, and the stability after quenching of the potassium salt catalyst is high, and thus the average molecular weight of the produced polycarbonate is maximum and the weather resistance is more excellent, and therefore it is further preferable.
The high molecular weight polycarbonate is prepared by a preparation system shown in FIG. 1.
The preparation system comprises a carbonic acid diester storage tank 1, a dihydroxyl compound storage tank 2, a catalyst storage tank 3, a mixing tank 4, a heater 18, a transesterification reactor, a pre-polycondensation reactor and a final polycondensation reactor which are connected in sequence.
In this application, compounding jar 4 is equipped with two at least, and it can make the material small batch mix, and each material quick mixing of being convenient for. In the figure, two mixing tanks 4 are shown in parallel, each mixing tank 4 being connected to a carbonic acid diester storage tank 1, a dihydroxy compound storage tank 2 and a catalyst storage tank 3, whereby carbonic acid diester, dihydroxy compound and catalyst can be directly fed into the mixing tank 4 for mixing. The evenly mixed materials of the two mixing tanks 4 are collected at a heater 18 and then directly sent into a transesterification reactor for transesterification.
If the temperature in the mixing tank 4 is too low, solidification of the material is easy to occur, and for this purpose, the outer side wall of each mixing tank 4 is coated with a heat tracing device (not shown in the figure), and the mixing tank 4 is preheated by the heat tracing device. The heat tracing device can be replaced according to the need, is mainly composed of a large jacket sleeve and a small jacket sleeve, and a small jacket sleeve is clamped between every two large jacket sleeves, and heating is achieved by introducing heating media into the large jacket sleeve and the small jacket sleeve. Compared with a jacket pipe with uniform size, the heating device can increase the contact area between the heating device and the mixing tank 4, further effectively improve the heat conduction efficiency, reduce the energy loss and promote the materials in the mixing tank 4 to be quickly heated to the set temperature.
The heating medium introduced into the large jacket pipe and the small jacket pipe by the heat tracing device can be steam or water or oil. If the temperature required for the mixing tank is relatively high (100-150 ℃), the heating medium is generally hot steam, wherein the pressure of the steam is usually maintained at less than or equal to 0.3MPa. However, the recycling rate of steam is low, and the cost of oil is high, so that when the temperature required by the mixing tank is low (below 100 ℃), the heating medium is generally hot water.
The transesterification reactor of this application is equipped with at least three, and links to each other in proper order between the transesterification reactor, and the material needs to carry regularly when taking place the transesterification from this, avoids the material to be in a state for a long time and leads to local overheat. The three successive column transesterification reactors 5 are shown in the drawing of the present application, since the temperature of the material in the plurality of transesterification reactors is now uniformly controllable and the column structure is more advantageous for rapid discharge of the material than horizontal.
The first column transesterification reactor 5 is also connected to a catalyst storage tank 3, whereby the catalyst according to the present application can be fed directly into the first column transesterification reactor 5, thereby ensuring that the material contains a sufficient amount of catalyst for polycondensation.
The three tower type transesterification reactors 5 are sequentially externally connected with a phenol purification tower 6 and a carbonic acid diester purification tower 7, waste gas generated by the three tower type transesterification reactors 5 is pumped into the same phenol purification tower 6 through a vacuum pump 8 for centralized purification, and the gas after phenol purification is introduced into the carbonic acid diester purification tower 7 for purification. Thus, if phenol is contained in the off-gas produced by the reaction of the carbonic acid diester and the dihydroxy compound, the phenol purification column 6 can effectively recover it, and the transesterification reaction is carried out forward to obtain a polycarbonate of high average molecular weight, and the phenol obtained by purification can be used as a by-product, which can add additional benefits to the production of the polycarbonate. In addition, the carbonic acid diester is usually added in excess in the reaction process to ensure that the dihydroxyl compound is completely reacted, so that the carbonic acid diester purifying column 7 can separate and recycle the excessive carbonic acid diester, thereby reducing the loss rate of the raw material.
The pre-polycondensation reactor comprises a tower pre-polycondensation reactor 9 and a horizontal pre-polycondensation reactor 10 which are connected in sequence. Wherein, the tower type pre-polycondensation reactor 9 is helpful for collecting materials and timely removing redundant waste gas; the circumferential area of the horizontal pre-polycondensation reactor 10 is large, and the temperature difference between the material at the circumferential side and the center of the reactor can be obviously reduced, so that the local overheating of the material is avoided, and side reactions such as branching, crosslinking and the like are reduced. A heater 18 is also connected between the tower pre-polycondensation reactor 9 and the horizontal pre-polycondensation reactor 10, and the heater 18 can further heat the material treated by the tower pre-polycondensation reactor 9.
The final polycondensation reactor is a horizontal final polycondensation reactor 11, which can also effectively avoid local overheating of materials and further reduce side reactions such as branching, crosslinking and the like. The horizontal final polycondensation reactor 11 is also sequentially externally connected with an extruder 12 and a granulator 13, and after the materials react in the horizontal final polycondensation reactor 11, the materials are extruded and granulated by the extruder 12 and the granulator 13 to obtain the polycarbonate with high molecular weight, the molecular weight distribution is narrower, and the average molecular weight is up to 4w. In order to reduce impurities in the polycarbonate, a screen changer 15 may be added between the horizontal type final polycondensation reactor 11 and the extruder 12, and a butterfly filter 16 may be added between the extruder 12 and the pelletizer 13.
On the basis, the tower type pre-polycondensation reactor 9, the horizontal pre-polycondensation reactor 10 and the horizontal final polycondensation reactor 11 are externally connected with a spray cooler 17, the three spray coolers 17 are vacuumized through the same vacuum pump 8, and waste gas generated by the reaction is discharged after being cooled and decontaminated by the spray coolers 17.
Example 1
A preparation method of high molecular weight polycarbonate adopts the preparation system and comprises the following steps:
(1) mixing and preheating:
diphenyl carbonate and bisphenol A are used as raw materials, potassium bicarbonate is used as a catalyst, 1.06mol of diphenyl carbonate and 100 mu mol of potassium bicarbonate are added into 1mol of bisphenol A, the raw materials and the catalyst are added into a mixing tank 4, the temperature of the materials in the mixing tank 4 is controlled to be 80-100 ℃, and the materials are mixed and preheated for 2-3 hours to obtain a premix; wherein the average molecular weight and the molecular weight distribution of the polycarbonate prepared at the preheating temperature and the preheating time are small, the embodiment is specifically described by taking the mixed preheating at 90 ℃ for 2.5 hours as an example.
(2) Transesterification:
and (3) sequentially conveying the premix obtained in the step (1) into three tower type transesterification reactors 5 for transesterification, gradually increasing the temperature of the three tower type transesterification reactors 5, sequentially carrying out transesterification for 1h at 210 ℃, 230 ℃ and 245 ℃ under 30kPa absolute pressure, and obtaining the pre-polycondensation material.
(3) Pre-condensing:
and (3) conveying the pre-polycondensation material obtained in the step (2) into a tower-type pre-polycondensation reactor 9, carrying out pre-polycondensation reaction for 1h at the temperature of 260 ℃ and the absolute pressure of 20kPa, and then conveying the pre-polycondensation material into a horizontal pre-polycondensation reactor 10, carrying out pre-polycondensation reaction for 2h at the temperature of 280 ℃ and the absolute pressure of 20kPa, thus obtaining the final polycondensation material.
(4) And (3) final polycondensation:
and (3) conveying the final polycondensation material obtained in the step (3) into a horizontal final polycondensation reactor 11, carrying out final polycondensation reaction for 2 hours at the temperature of 280 ℃ and the absolute pressure of 15kPa, and carrying out extrusion granulation to obtain a polycarbonate finished product.
Examples 2 to 4
Examples 2-4 the parameters of the transesterification, pre-polycondensation and final polycondensation reactions were adjusted on the basis of the procedure of example 1, the specific adjustments being given in the following table.
TABLE A reaction parameter Table for examples 1-4
Examples 5 to 6
Examples 5-6 the temperature and time of the mixing pre-heating were adjusted on the basis of the method of example 1. Wherein, in example 5, the mixture was preheated at 70 ℃ for 4 hours; example 6 mixing pre-heat for 2h at 120 ℃.
Examples 7 to 8
Examples 7 to 8 the catalyst type was adjusted based on the method of example 1. Wherein, the catalyst in the embodiment 7 is sodium bicarbonate, and the mixing preheating temperature is 50 ℃; the catalyst in example 8 was potassium carbonate.
Comparative example
Comparative example 1
In this comparative example, based on the method of example 1, the temperature of each of the three column transesterification reactors 5 was 210℃and the absolute pressure was 30kPa, and the transesterification reactions were 1 hour.
Comparative example 2
This comparative example was conducted by the method of example 1, which was followed by providing only one column transesterification reactor 5, and conducting transesterification at a temperature of 210℃and an absolute pressure of 30kPa for 3 hours.
Comparative example 3
This comparative example was based on the method of example 1, in which the horizontal precondensation reactor 10 was replaced with a column precondensation reactor 9, and in which the horizontal final polycondensation reactor 11 was replaced with a column final polycondensation reactor.
Performance test
The polycarbonates produced in examples 1 to 8 and comparative examples 1 to 3 were examined for average molecular weight and molecular weight distribution, and the results are shown in Table II below.
The detection method comprises the following steps: gel permeation chromatography was used, type 150C from Waters company. The polycarbonate sample is firstly dried in vacuum, then prepared into a PC solution with 0.3 weight percent by taking tetrahydrofuran as a solvent, and the sample is filtered by a filter membrane with the thickness of 0.5 mu m before sample injection. High performance PS gel chromatographic column (10) 4 -10 3 One linear three in series), the temperature is 25 ℃, the sample injection amount is 40mL, and the sample is obtained after data processing after testAverage molecular weight and molecular weight distribution index; wherein the molecular weight is most uniform when the molecular weight distribution index is 1, and the larger the molecular weight distribution index is, the wider the molecular weight distribution is, and the larger the polydispersity degree is.
Table II results of the tests of examples 1 to 8 and comparative examples 1 to 3
Referring to Table II, by comparing the detection results of examples 1 to 8 with those of comparative examples 1 to 3, the preparation method of the present application can avoid local overheating of materials, so that transesterification reaction proceeds smoothly, thereby reducing side reactions such as branching and crosslinking, and the like, and the polycarbonate prepared by the method has a uniform molecular weight distribution, an average molecular weight of up to 4w, and a higher molecular weight.
As a result of comparing the results of the tests in examples 1 and 5 to 8, it was found that the catalyst of the present invention was potassium bicarbonate, and the potassium bicarbonate was mixed and preheated at 80 to 100℃for 2 to 3 hours, which caused the raw materials to undergo the transesterification reaction slowly, and reduced the side reactions such as branching and crosslinking, and the like, whereby the average molecular weight of the polycarbonate obtained was large and the molecular weight distribution index was closest to 1, and example 4 was further preferred.
Example 9
A polycarbonate which can be produced by the production method of any one of examples 1 to 8, this example being preferably produced by the method of example 4.
The present embodiment is merely illustrative of the present application and is not intended to be limiting, and those skilled in the art, after having read the present specification, may make modifications to the present embodiment without creative contribution as required, but is protected by patent laws within the scope of the claims of the present application.
Claims (4)
1. A method for preparing high molecular weight polycarbonate, which is characterized in that: diphenyl carbonate and bisphenol A are used as raw materials, a catalyst potassium bicarbonate is added, mixed and preheated, and transesterification, pre-polycondensation and final polycondensation are sequentially carried out under the conditions that the temperature is 210-320 ℃ and the absolute pressure is 0.01-30 kPa; the diphenyl carbonate, bisphenol A and potassium bicarbonate are mixed and preheated for 2-3 hours at the temperature of 80-100 ℃;
the transesterification adopts at least three tower transesterification reactors (5) which are connected in sequence, the temperature of the three tower transesterification reactors (5) is gradually increased, the temperature is 210-240 ℃, the temperature is 230-250 ℃ and the temperature is 245-270 ℃ in sequence, the pre-polycondensation adopts at least one horizontal pre-polycondensation reactor (10), and the final polycondensation adopts at least one horizontal final polycondensation reactor (11).
2. The method for producing a high molecular weight polycarbonate according to claim 1, wherein: the mixing preheating adopts at least two mixing tanks (4), each mixing tank (4) is provided with a heat tracing device, the heat tracing device comprises a large jacket sleeve and a small jacket sleeve, and one small jacket sleeve is clamped between every two large jacket sleeves.
3. The method for producing a high molecular weight polycarbonate according to claim 1, wherein: the first tower type transesterification reactor (5) is externally connected with a catalyst storage tank (3).
4. The method for producing a high molecular weight polycarbonate according to claim 1, wherein: the tower type transesterification reactor (5) is sequentially externally connected with a phenol purification tower (6) and a carbonic acid diester purification tower (7), and gas pumped out of the tower type transesterification reactor (5) is processed by the phenol purification tower (6) and then is introduced into the carbonic acid diester purification tower (7).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111109227.6A CN113801313B (en) | 2021-09-22 | 2021-09-22 | Preparation method of high molecular weight polycarbonate and polycarbonate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111109227.6A CN113801313B (en) | 2021-09-22 | 2021-09-22 | Preparation method of high molecular weight polycarbonate and polycarbonate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113801313A CN113801313A (en) | 2021-12-17 |
| CN113801313B true CN113801313B (en) | 2023-06-13 |
Family
ID=78896303
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111109227.6A Active CN113801313B (en) | 2021-09-22 | 2021-09-22 | Preparation method of high molecular weight polycarbonate and polycarbonate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113801313B (en) |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11310631A (en) * | 1998-04-28 | 1999-11-09 | Daicel Chem Ind Ltd | Manufacture of polycarbonate |
| JP5200375B2 (en) * | 2006-12-18 | 2013-06-05 | 三菱化学株式会社 | Method for producing polycarbonate resin |
| CN101643542B (en) * | 2008-08-05 | 2012-01-11 | 中国科学院化学研究所 | Preparation method of aliphatic polycarbonate with high molecular weight |
| CN102372848B (en) * | 2010-08-09 | 2016-03-16 | 奥克化学扬州有限公司 | A kind of method of preparing polycarbonate through melt transesterification technology |
| DE102012105296A1 (en) * | 2012-06-19 | 2013-12-19 | Epc Engineering Consulting Gmbh | Process and plant for the production of polycarbonate |
| CN105175703A (en) * | 2015-10-15 | 2015-12-23 | 宁波浙铁大风化工有限公司 | Equipment for preparing polycarbonate |
| CN105175706A (en) * | 2015-10-15 | 2015-12-23 | 宁波浙铁大风化工有限公司 | High-light-permeability panlite and production method thereof |
| CN105175705A (en) * | 2015-10-15 | 2015-12-23 | 宁波浙铁大风化工有限公司 | Preparation device of polycarbonate |
| CN105504255B (en) * | 2016-01-11 | 2017-06-16 | 中蓝晨光化工研究设计院有限公司 | A kind of continuous fusion polymerization prepares the production technology of makrolon |
| CN105949451B (en) * | 2016-07-14 | 2017-10-20 | 中国科学院过程工程研究所 | A kind of method of alkali ionic liquid catalyzed preparation of poly carbonic ester |
| CN106947072A (en) * | 2017-04-20 | 2017-07-14 | 宁波浙铁大风化工有限公司 | A kind of preparation technology of makrolon |
| CN110982054B (en) * | 2019-12-28 | 2021-03-12 | 中国科学院过程工程研究所 | Composite catalyst for catalytically synthesizing polycarbonate and method for catalytically synthesizing polycarbonate |
-
2021
- 2021-09-22 CN CN202111109227.6A patent/CN113801313B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113801313A (en) | 2021-12-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100357656B1 (en) | Method for producing polycarbonate | |
| US7999056B2 (en) | Continuous production method and production apparatus of aromatic polycarbonate | |
| JP4145662B2 (en) | Continuous production method of polycarbonate | |
| KR100354801B1 (en) | Method for producing polycarbonate | |
| KR20010032512A (en) | Copolycarbonate and process for producing the same | |
| JP4104595B2 (en) | Method for producing high molecular weight polycarbonate resin | |
| JPH06234845A (en) | Production of aromatic polycarbonate | |
| WO2008012986A1 (en) | Process for producing aromatic polycarbonate | |
| CN113801313B (en) | Preparation method of high molecular weight polycarbonate and polycarbonate | |
| JP5655495B2 (en) | Polycarbonate resin and method for producing the same | |
| CN1286712A (en) | Process for producing polycarbonate and optical-disk substrate | |
| JP2000186137A (en) | Polycarbonate and optical material | |
| KR102404309B1 (en) | Aromatic polycarbonate resin composition and method for producing aromatic polycarbonate resin | |
| KR20010093288A (en) | Method for preparing polycarbonates of enhanced crystallinity | |
| JP4957311B2 (en) | Continuous production method of aromatic polycarbonate | |
| JP5303847B2 (en) | Method for purifying carbonic acid diester and method for producing polycarbonate resin | |
| JP5464166B2 (en) | Method for purifying carbonic acid diester and method for producing polycarbonate resin | |
| JP2013166963A (en) | Method for continuously producing aromatic polycarbonate | |
| JPH107785A (en) | Polycarbonate for optical material | |
| CN103965456A (en) | Method for Preparing Polycarbonate Resin | |
| KR102530453B1 (en) | Method for preparing granule polycarbonate | |
| CN108948341B (en) | Device and method for preparing aromatic polycarbonate | |
| CN1649934A (en) | Recycle process for polycondensation resins | |
| JPH02153924A (en) | Production of polycarbonate | |
| JP5585276B2 (en) | Method for producing polycarbonate resin |
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 |