JP2622234B2 - Continuous production method of polycarbonate by interfacial method. - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous production method of a polycarbonate by an interfacial method, and more particularly, to a static mixer and a continuous stirring reactor.
irredTank Reactor, hereafter CSTR
Using abbreviated), to form a high molecular weight polycarbonate before polymer from first relates further process for catalytically preparing poly carbonate ester <br/> Le high molecular weight.

[0002]

BACKGROUND OF THE INVENTION U.S. Pat. No. 4,737,573 discloses a process for the preparation of linear polycarbonates in which phosgene is prepared from water, a water-insoluble organic liquid and at least one dihydroxy aromatic compound in a tank reactor. Simultaneously with the introduction into the homogeneous mixture, an alkaline aqueous solution comprising an alkali metal or an alkaline earth metal is introduced at a rate sufficient to maintain the pH of the aqueous phase at 8-11, and the mixture is maintained at 15-50 ° C. The phase volume ratio is 0.4-1.0: 1 and the phosgene to dihydroxyaromatic compound molar ratio is at least 1.
And stirring the mixture at a speed sufficient to keep the mixture from separating into the aqueous and organic phases to form a bischloroformate composition, a mixture of this composition with water and a water-insoluble organic liquid. The catalyst is introduced into the tank reactor containing (stirring) and an alkaline aqueous solution of an alkali metal or alkaline earth metal sufficient to maintain the pH of the aqueous phase at 10-14 is introduced. The example uses an excess of 25 mole% phosgene and the reaction product exiting the first tank reactor has only a few dihydroxyaromatic compound molecules.

US Pat. No. 5,037,941 discloses a method for preparing a prepolymer of a polycarbonate by an interfacial method, and US Pat. No. 5,037,942 discloses a process for producing a prepolymer of a polycarbonate.
A method similar to was disclosed. The process of U.S. Pat. No. 5,037,942 comprises the steps of (a) combining at least a static mixer in a reactor with phosgene, one or more dihydroxyphenols, one or more polyhydroxyphenols, a halogenated organic solvent and an aqueous caustic solution. And a fine dispersion of these partially phosgenated derivatives of phenol is formed in the aqueous phase, and (b) a reaction is carried out for 20 to 40 seconds at the residence time stage of the reactor, and a crude dispersion containing these derivatives is obtained. And (c)
The mixing and reaction of the above (a) and (b) are repeated until these phenols are completely phosgenated, (d) an additional aqueous caustic solution is added to the dispersion, and (e) the dispersion is added. Cooling to 25-45 ° C, (f) molecular weight of 40
The mixing and reaction of (a) and (b) are repeated until a dispersion of the polycarbonate prepolymer of 00-12000 is obtained.

US Pat. No. 5,037,491 and US Pat. No. 5,037,492 both produce a high molecular weight carbonate prepolymer in a static mixer, but their phosgenation efficiency is low and phosgene conversion is low. High degree of hydrolysis. For example, Examples 1, 2, and 6 of the specification of U.S. Pat. No. 5,037,492 carry out the reaction with an excess of 40, 32.2 and 4 mol% of phosgene, respectively. In both of these patent methods, the oligomer mixture (including the aqueous phase and the organic phase) in step (f) is recirculated to the feed point in step (a) to reduce the concentration of the dihydroxyphenol compound reactant in the aqueous caustic solution ( Disadvantageous to the phosgenation reaction) and the temperature at the feed site rises (phosgene is easily hydrolyzed).

EP-A-0 472 848 A1 discloses a continuous process for producing oligomers of polycarbonates, in which a dihydroxy aromatic compound and phosgene undergo an interfacial oligomerization reaction in the presence of a catalyst and a base. Performed in a reactor system, without adding a chain terminator to the reaction mixture, and a catalyst of 200 ppm or less (based on an organic solvent)
And at least one static mixer and plug flow, optionally combined with a CSTR reactor. All of the examples described therein react with excess phosgene with 2,2-bis (4-hydroxyphenyl) propane (abbreviated as Bisphenol A, BPA), and the phosgene feed pressure has a high recycle ratio value. 1
It increases as it reaches zero, increasing the chance of phosgene leakage. In addition, this proposed European patent application has the same disadvantages as the above-mentioned U.S. Pat. No. 5,037,941 and U.S. Pat.

[0006] James M. Silva & Philip G. Kosky are Ind.
Eng. Chem. Res. 1991, 30, 468-474
Aqueous Phase in the Interfacial Synthesis of Poly
carbonate. 2.Appli-cation of Ionic Equilibria to
The Semibatch Polycarbonate shows that: (1) When BPA is completely dissolved in NaOH to form a saturated aqueous solution, its pH is>11; (2) The pH of the aqueous solution of the reaction mixture is 10-11. Time,
BPA solids dissolve completely only when the BPA conversion is about 0.8 or more.

In a continuous method for producing a polycarbonate,
Since the BPA feed is restricted to be continuously fed with the solution by the transport pump, BPA precipitation cannot be avoided unless the pH of the BPA saturated alkaline aqueous solution at the feed site is about 12.2. U.S. Pat. No. 5,037,941; U.S. Pat. No. 5,037,942 and EP-A-04728.
The 48A1 method recycles the oligomer mixture to the reactant feed location, so the pH of the aqueous solution at the feed location is affected by the recycle stream and is difficult to control.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is mainly to synthesize a polycarbonate ester prepolymer having a weight average molecular weight of about 21,000 and then mix it with a catalyst organic solvent to form a polymer polycarbonate. Provided is a method for continuously producing a polymer polycarbonate by an interfacial method for producing an ester.

Another object of the present invention is to provide an organic solution of phosgene at 0 to 15 ° C. and an aqueous alkaline solution of a dihydroxy phenol compound at 5 to 10 ° C. in a first stage static mixer maintained at 5 to 15 ° C. Provided is a method for continuously producing a polymer polycarbonate by an interfacial method in which a phenol compound is subjected to a phosgenation reaction.

Another object of the present invention is to carry out the production of a polycarbonate prepolymer in the circuit reactor system after the first stage static mixer, wherein the circuit reactor system includes a second stage static mixer. A CSTR reactor in series, wherein additional aqueous alkali solution is added to the CSTR reactor and a portion of the reaction mixture exiting the CSTR reactor is recycled to the inlet of the second stage static mixer, preferably the CSTR reactor. A continuous process for the production of polymeric polycarbonates by the interfacial method, in which all or part of the aqueous phase is removed before the reaction stream leaving the reactor is recycled.

Another object of the present invention is to provide an interfacial polycondensation reaction in which an aqueous solution of a polycarbonate prepolymer and an organic solution of an amine catalyst are mixed and introduced into a multi-layer plug-type fluid type CSTR reactor. Provided is a method for continuously producing a high molecular weight polycarbonate by a method.

[0012]

SUMMARY OF THE INVENTION A continuous process for producing a polycarbonate by the interfacial method of the present invention comprises the following steps: a. One or more kinds of dihydroxyphenols, any one or more kinds of phenols having two or more hydroxy, a caustic aqueous solution, a halogeno organic solvent, and phosgene are introduced into the first-stage static mixer, and the aqueous phase is added to the aqueous phase. Forming a dispersion of partially phosgenated derivatives of these phenols; b. The reaction mixture effluent from the first stage static mixer of step a is combined with the recycled oligomer reaction mixture and introduced into the second stage static mixer to further remove any remaining unreacted phenol in the aqueous phase. Invert; c. Introducing the reaction mixture effluent from the second stage static mixer of step b into the CSTR reactor and retaining it for about 10-60 minutes, while adding additional aqueous caustic to the reaction mixture of the CSTR reactor; d. The reaction mixture discharged from the CSTR reactor is divided into two streams, and the first stream is recycled to step b to form the recycled oligomer reaction mixture, and the polycarbonate ester prepolymer having a weight average molecular weight of about 21,000 is converted to the second stream. Formed in the split organic phase, and the second split phase is free of those unreacted phenol reactants. In the above method, preferably, the second split stream obtained in step d is mixed with an amine catalyst dissolved in an organic solvent or water, and an interfacial polycondensation reaction is carried out in a plug-like flow CSTR reactor having a plurality of layers.

[0013]

The main reaction which takes place in step a of the process of the present invention is the phosgenation reaction of these polyhydroxyphenols with phosgene, of which mono- or bischloroformate esters containing one or two phenol molecules are formed. I do. Since no recycle stream has yet been introduced into the first stage static mixer during step a, the pH of the aqueous solution of the reaction mixture therein and its conditions are easier to control, and phosgene is also fed at a lower pressure. Is done.

The main benefit of the second stage static mixer of step b of the process of the present invention is that the unreacted multi-hydroxyphenol compound is substantially lower, eg, less than about 2%, before entering the CSTR reactor of step c. Converted to content. The introduction of the recycled oligomer reaction mixture promotes the conversion of unreacted multi-hydroxyphenol compound because it increases the oligomer concentration in the reaction compound in the second stage static mixer. Preferably, a portion or all of the aqueous phase therein is first removed before being introduced into the second stage static mixer as a first split of the recycled oligomer reaction mixture.

In step c of the method of the present invention, the reaction mixture is controlled to a desired pH and the oligomerization reaction is carried out since an additional aqueous caustic solution is added.

[0016]

DISCLOSURE OF THE INVENTION The present invention relates to a continuous production method of a high-molecular-weight polycarbonate by an interfacial method.
, And then a catalytic reaction is carried out in the presence of an amine catalyst to produce a high-molecular-weight polycarbonate.

A more preferred embodiment of the invention comprises the following steps: a. In a first-stage static mixer having a cooling sleeve and maintaining the temperature at 5 to 20 ° C., one or more kinds of dihydroxyphenols, any one or more kinds of phenols having two or more hydroxys, and an aqueous caustic solution , A halogeno organic solvent and phosgene are mixed to form a dispersion of a partially phosgenated derivative of these phenols in the aqueous phase. The amount of the caustic used is such that the dihydroxyphenol and the polyhydroxyphenol are mixed in the aqueous phase. And the temperature of the reaction mixture feed is 0-15 ° C .; b. The reaction mixture discharged from the first-stage static mixer in step a is combined with the recycle oligomer reaction mixture and introduced into the second-stage static mixer. The second-stage static mixer is disconnected compared to the first-stage static mixer. Large area; c. Introducing the reaction mixture effluent from the second stage static mixer of step b into the CSTR reactor and retaining it for about 10-60 minutes, while adding additional aqueous caustic to the reaction mixture of the CSTR reactor; d. The reaction mixture discharged from the CSTR reactor is divided into two streams, and the first stream is separated into an aqueous phase and an organic phase, and the organic phase is recycled to the step b to obtain a recycled oligomer organic phase solution in the step b. Forming a polycarbonate prepolymer having an average molecular weight of about 21,000 in the second split organic phase, and the second split phase is substantially free of those unreacted phenol reactants; and e. The second split stream obtained in step d is mixed with an organic solvent containing an amine catalyst, and an interfacial polycondensation reaction is carried out in a plugged flow CSTR reactor having a plurality of layers.

In step a), the reaction temperature is kept low, the rate of phosgene hydrolysis is reduced, and the dihydroxyphenol and polyhydroxyphenol are completely dissolved in the aqueous phase, and the reaction of phosgene with those phenols Because of the increased rate, the degree of phosgene hydrolysis can be reduced.

In a preferred specific embodiment of the present invention,
When the reaction of step a is carried out with a feed mixture containing phosgene with a molar ratio to BPA of about 1.05, the conversion of BPA reaches 80-85 mol% and the pH of the aqueous solution is from about 12.2 to about 9 at the feed inlet. It decreased to -11.8.

The unreacted phenol feed in the reaction mixture from step a is followed by a phosgenation and oligomerization reaction in step b, the temperature of the reaction mixture leaving the second stage static mixer being about 15-25. C., the feed of unreacted phenol fell below 2%, and the pH of the aqueous solution further dropped. The increased cross-sectional area of the second stage static mixer compared to the first stage static mixer is to reduce sudden pressure rise due to the introduction of the recirculating flow.

The pH of the aqueous solution of the reaction mixture in the CSTR reactor of step c is maintained at 11-12.5, preferably 11.5-12.0, by addition of the additional aqueous caustic solution and the reaction temperature is about 20-40 ° C. In the CSTR reactor of step c, the oligomerization reaction was carried out to the desired extent and the unreacted residual phenol reactant was almost completely converted. If the reaction mixture leaving the first stage static mixer of step a is at the appropriate pH, it is only necessary to recycle the organic phase solution of step d to step b. This is very advantageous, because the unreacted phenol feed (dissolved in the aqueous phase) entering the reaction mixture of step b is not diluted in the recycle stream and the pH of the aqueous solution is recycled. Not affected by flow. If necessary, recirculate part of the aqueous phase of step d together with said organic phase solution to step b,
The pH of the aqueous phase of the second stage static mixer reaction mixture can also be adjusted. The preferred recirculation volume ratio (ratio of the volumetric flow of the second stage static mixer to the volumetric flow of the first stage static mixer) is between 3-10.

Plug-like flow type CST having a plurality of layers in step e
In the R reactor, those having preferably 6 or more layers, particularly 10 layers, are optimal. Plug flow type CST having appropriate plural layers
The R reactor is already described in U.S. Pat. No. 4,737,573, the content of which is a reference for the present invention. An aqueous caustic solution is optionally introduced into the plugged fluid type CSTR reactor, and the aqueous solution for the polycondensation reaction is controlled between pH 9-11. Most of the polycondensation reactions are based on the multi-layer plug-like fluidized CST.
An aqueous acid solution is added to several layers (before the polycondensation reaction product leaves the plug-flow CSTR reactor) in the front several layers (one near the inlet) of the R reactor, and then the reaction product is obtained. Can be neutralized to pH. The dihydroxyphenol applied in the method of the present invention is disclosed in U.S. Pat.
573, the contents of which are used as reference material for the present invention.
Suitable dihydroxyphenols are, for example: 2,2-bis (hydroxyphenyl) propane (Bisphe
nol A, abbreviated as BPA), 4,4′-bis (4-hydroxyphenyl) propane, 4,4 ′-(1-α-methylbenzylidene) bisphenol, 4,4′-cyclohexylidene) bisphenol, 1'-bis (4-hydroxyphenyl) cyclohexane 2,2'-bis (4-hydroxy-3-methylphenyl) propane, tetramethyl-bisphenol-A, bis (4-hydroxy-3,5-dimethylphenyl) methane 4,4'-ethylidene-bisphenol, 4,4'-methylene-bisphenol, dihydroxydiphenylmethane, and methyl-isobutyl-methylene-bisphenol. The above dihydroxyphenols are used alone or in a mixture with one another. When the phenol having two or more hydroxy groups is fed, a branched polycarbonate can be formed. Preferred phenols having two or more hydroxy groups are found in US Pat. No. 5,037,942, the contents of which are incorporated by reference. A preferred example of a phenol having three or more hydroxy groups is 1,1,1-
Tris (4-hydroxyphenyl) ethane and 4,4'-
Bis (4-hydroxyphenyl) -4 "-(4-hydroxyphenyl) phenylmethane. These phenols having two or more hydroxy groups may be used in an amount of 0,1.
1-2.0% by weight (based on the weight of the dihydroxyphenol reactant).

The appropriate feed molar ratio of phosgene to dihydroxyphenol is 1.0-2.0, preferably 1.01.
-1.10.

Examples of the halogeno organic solvent applicable to the present invention include chlorobenzene, chloroform, carbon tetrachloride,
1,2-dichloroethane, methylene chloride, 1,1,2-
Trichloroethane, tetrachloroethane and mixtures thereof.

The common alkali in the aqueous caustic solution used in the present invention is an alkali metal or alkaline earth metal hydroxide such as sodium hydroxide, potassium hydroxide or calcium hydroxide. The concentration of the aqueous caustic solution is not particularly limited to 0.2-19M.

The static mixers used in the present invention are well known and are described, for example, in Chen et al., Chemical Engineer.
ing, Mar. 19, 1973, p. 105-111
Published on the Internet. The static mixer applied to the method of the present invention is a static mixer having 21 elements inside, and the speed of the feed fed to the static mixer is about 4.
0 cm / sec or more linear velocity, preferably 60-100
cm / sec.

The amine catalyst used in the present invention is a tertiary amine and a pyridine compound, particularly preferably a trialkylamine having 6 or more carbon atoms. As a suitable example,
Triethylamine, tri-n-propylamine, diethyl-n-propylamine, tri-n-butylamine, 4-dimethylpyridine and the like. Other catalysts that are the same in function or operation as the amine catalysts of the present invention can also be used.

[0028]

The method of the present invention will be described below with reference to examples, but is not intended to limit the scope of the present invention.

[0029]

Example 1 Phosgene (20% in methylene chloride, flow rate 131.21 g / min) and methylene chloride (329.7)
9g / min) continuously, and the 5-
Cooled to 10 ° C. Before the above components enter the first stage static mixer via the nozzle, 21.114 L / hr of 5-
2,2-bis (hydroxyphenyl) cooled to 10 ° C
It is mixed with an aqueous solution of propane (abbreviated as Bisphenol A, BPA) and sent to the first stage static mixer together. The BP
The A aqueous solution is composed of 7487 g of BPA, 123 g of t-butylphenol, 5446 g of a 50% aqueous sodium hydroxide solution and 39.50 L of water. The first stage static mixer No. 6 It consists of a T4-21 static mixer unit, each unit is 16.5cm long and 5mm inside diameter
And manufactured by Noritake Japan. A cooling sleeve was installed in the first-stage static mixer, and 1
A 0 ° C refrigerant is passed through the cooling sleeve and the mixture in the first stage static mixer is maintained at 9-20 ° C.

The reaction mixture was placed in a second stage static mixer (No.
T6-21, length 25cm, inside diameter 8mm, Nori Japan
(manufactured by Take Inc.) merges with the recycle stream before introduction. The second stage static mixer consists of 16 T6-21 units.

The reaction mixture flowing out of the second-stage static mixer was charged to a reaction solution having a volume of 36 L and a C having an anchor type stirrer.
The reactor was introduced into the STR reactor, and a cooling sleeve was placed in the CSTR reactor, and the reaction liquid therein was maintained at 20-25 ° C. 50% aqueous sodium hydroxide solution 12-24 g / m
at a rate of 11-1 to the CSTR reactor and adjust the pH to 11-1.
Maintained at 2. The reaction mixture stream flowing out of the CSTR reactor is sent to a tank, and the inside of the tank becomes both an aqueous layer and an organic layer.
Is recirculated to the inlet of the second stage static mixer at a recycle ratio of (the definition of the recirculation ratio is the ratio of the volume flow of the second stage static mixer to the volume flow of the first stage static mixer) , Merging with the reaction mixture flowing out of the first stage static mixer.

Before the reaction stream flowing out of the CSTR reactor enters the tank, a part of it is led out in a tributary manner, and when the reaction time is about 140 minutes, this tributary is fed into a 10-layer plug-flow type CSTR reactor. To perform a polycondensation reaction. At the same time, a solution of triethylamine in methylene chloride (5% by volume) is introduced, the amount of which is 1 mol% of the BPA feed.
It is. A 50% aqueous sodium hydroxide solution is optionally introduced to maintain the pH of the reaction mixture at 9-11. The liquid flowing out of the tenth layer is introduced into a separation tank, where it is separated into two phases, an organic layer and an aqueous solution layer. The organic layer is taken out and the volume of the diluted alkaline liquid (about 1/4 to 1/5) (150 g 3%
Wash with sodium hydroxide aqueous solution and 5 L water), further take out the organic layer, dilute acid solution of about 1/4 to 1/5 its volume (100 g 0.74% hydrochloric acid aqueous solution and 5 L water mixed)
And finally three times with the same volume of water as the organic layer. The organic solvent contained therein was evaporated from the separated organic layer to obtain a crude polycarbonate film. The intrinsic viscosity (IV) of the film is 1%
(G / ml) measured with a methylene chloride solution and a Ubbelode viscometer. Table 1 shows the experimental conditions and results.
Shown in

[Table 1]

The water-washed organic solution of polycarbonate obtained above is mixed with the same volume of n-hexane to precipitate a polycarbonate resin. The average molecular weight is 1% (g / g).
ml) methylene chloride solution and three GPC columns (Mil
lipore WatersNo. 10681, 7.8
× 300 nm, 3 columns in series), eight of which were polystyrene (having a molecular weight of 3100K,
240K, 35K, 5K, 390K, 102K, 8.5
K, 1.8K) and chloroform as the eluent. Table 2 shows the results. This polycarbonate resin has a higher average molecular weight than the crude polycarbonate film,
Molecular weight distribution and I.I. V. The values are narrow, because some of the low molecular weight oligomers and impurities were dissolved in the n-heptane solvent.

[Table 2]

[0034]

Example 2 The procedure was as in Example 1, except that the recirculation ratio was 4.0 and the second stage static mixer consisted of eight T6-21s. The experimental conditions and results are shown in Tables 3 and 4.

[Table 3]

[Table 4] From the results in Tables 3 and 4, this example used a second-stage static mixer shorter than Example 1 and a high recirculation ratio, but the results were not inferior to Example 1.

[0035]

Example 3 The second stage static mixer used for test C818 was composed of four T6-21s and had a recirculation ratio of 7.2.
To 5; 12 second stage static mixer used for test C821
The same procedure as in Example 1 was carried out except that the recycle ratio was 3.96. The experimental conditions and results are shown in Tables 5 and 6.

[Table 5]

[Table 6]

[0036]

EXAMPLE 4 The procedure was as in Example 1, except that the recirculation ratio was 4.0 and the second stage static mixer consisted of eight T6-21s. The experimental conditions and results are as shown in Tables 7, 8 and 9.

[Table 7]

[Table 8]

[Table 9]

[0037]

Example 5 The procedure was as in Example 4, except that the linear velocity, recirculating stream velocity and recirculating ratio of the feed mixture were as shown in Tables 10 and 11. Experimental conditions and results are shown in Tables 10 and 11.
It is as follows.

[Table 10]

[Table 11]

Claims (12)

(57) [Claims] 1. A method according to claim 1, One or more kinds of dihydroxyphenols, any one or more kinds of phenols having two or more hydroxy, a caustic aqueous solution, a halogeno organic solvent, and phosgene are introduced into the first-stage static mixer, and the aqueous phase is added to the aqueous phase. Forming a dispersion of partially phosgenated derivatives of these phenols; b. The reaction mixture effluent from the first stage static mixer of step a is combined with the recycled oligomer reaction mixture and introduced into the second stage static mixer to further remove any remaining unreacted phenol in the aqueous phase. Invert; c. Introducing the reaction mixture effluent from the second stage static mixer of step b into the CSTR reactor and retaining it for about 10-60 minutes, while adding additional aqueous caustic to the reaction mixture of the CSTR reactor; d. The reaction mixture discharged from the CSTR reactor is divided into two streams, and the first stream is recycled to step b to form the recycled oligomer reaction mixture, and the polycarbonate ester prepolymer having a weight average molecular weight of about 21,000 is converted to the second stream. A continuous production of polycarbonate by an interfacial method comprising forming in the split organic phase and said second split phase contains substantially no unreacted phenolic reactants. 2. The process of claim 1 wherein prior to introducing the first split stream of step d into the second stage static mixture of step b, the aqueous phase is partially or almost entirely removed therein. 3. The process of claim 1 wherein prior to introducing the first split stream of step d into the second stage static mixture of step b, substantially all of the aqueous phase therein is removed. 4. The method of claim 1 wherein the cross-sectional area of the second stage static mixer is greater than the cross-sectional area of the first stage static mixer. 5. The method of claim 1 wherein the speed of the feed mixture in the first and second stage static mixers is a linear speed of 40 cm / sec or more. 6. The reactant introduced into the first-stage static mixer is zero.
Between −15 ° C. and the second stage static mixer has a cooling sleeve to reduce the temperature of the reaction mixture therein to 5-2
The method of claim 1 wherein the temperature is maintained at 0 ° C. 7. The dihydroxyphenol is 2,2-bis (hydroxyphenyl) propane, and the aqueous solution of caustic introduced into the first-stage static mixer has a caustic content of 2,2-bis. (Hydroxyphenyl)
7. The method of claim 6, which is sufficient to completely dissolve propane. 8. The process of claim 7 wherein substantially all of the aqueous phase is first removed prior to introducing the first split of step d into the second stage static mixture of step b. 9. The method according to claim 2, wherein said second stage static mixer has a volumetric flow rate.
The recirculation ratio value representing the ratio of the volumetric flow rate of the first stage static mixer is
9. The method of claim 8, which is between 3-10. 10. The residence time of the reactant in the second-stage static mixer is about 1-10 seconds, the temperature of the reaction mixture flowing out of the second-stage static mixer is 15-25 ° C., and the aqueous phase The method according to claim 9, wherein the pH of the polymer is 9-11.8 and the amount of unreacted 2,2-bis (hydroxyphenyl) propane monomer is 2.0% by weight or less. 11. The temperature of the reaction mixture in the CSTR reactor of step c is -20.degree.-40.degree.
11. The method of claim 10, wherein the temperature is maintained between 12.5. 12. The method according to claim 1, wherein the second split stream obtained in the step d is mixed with an amine catalyst dissolved in an organic solvent or water, and an interfacial polycondensation reaction is carried out in a plugged fluidized CSTR reactor having a plurality of layers.