JPS62260824A - Production of polycarbonate copolymer - Google Patents

Abstract

PURPOSE:To obtain a polycarbonate copolymer of improved oil resistance, by subjecting a bisphenol, a bisphenol sulfone and phosgene to a specified reaction via a cooligomer thereof. CONSTITUTION:In the production of a polycarbonate copolymer formed of a bisphenol, a bisphenol sulfone and phosgene, the reaction is performed as follows. A mixture of the bisphenol with the bisphenol sulfone is reacted with the phosgene to produce a cooligomer. This cooligomer is reacted with the bisphenol and/or the bisphenol sulfone to obtain the purpose copolymer. As the bisphenol used, 2,2-bis(4-hydroxydiphenyl)propane (called also bisphenol A) is particularly preferable.

Description

DETAILED DESCRIPTION OF THE INVENTION ['Industrial Field of Application] This invention relates to a method for producing a polycarbonate copolymer.

[Prior art and its problems] Polycarbonate resin produced by the reaction of bisphenols such as bisphenol A with phosgene is an engineering resin that is transparent and has excellent heat resistance and impact resistance, but it is a petroleum-based resin. It has the disadvantage of low resistance to A polycarbonate copolymer copolymerized with bisphenol sulfone is known to improve this drawback.

As a method for producing this copolymer, there has been a method in which phosgene is continuously blown into a mixture of bisphenol A and bisphenol sulfone until the end (Japanese Patent Application Laid-open No. FFL 54-288).
No. 116), <@) Screw 7 x/k in advance
A: React with tophosgene to produce oligomers.

, a method in which bisphenol sulfone is added to the oligomer to perform a polycondensation reaction (41F Opening and Closing No. 58-87720),
■ A method of producing a cooligomer by reacting bisphenol A, bisphenol sulfone, and phosgene in the presence of a quaternary ammonium salt, and then polycondensing the cooligomer in the presence of a tertiary amine (#Opening/Closing 61- 4253
No. 8).

However, in the above method (1),
As pointed out in No. 20, when sulfone bisphenol is contained in an amount of 50 mol % or more, problems arise regarding phase separation and separation of the polycarbonate copolymer produced.

In the method (2) above, the amount of sulfone in the copolymer produced is 18
There was a limit at ~45 mol%.

Furthermore, in the method (2) above, in order to suppress the generation of emulsions, in addition to the conventional tertiary amine, a quaternary ammonium salt must be used at the stage of producing the cooligomer.

That is, in the conventional production techniques, there were problems such as difficulty in producing a polycarbonate copolymer with a large amount of sulfone and improved heat resistance, especially oil resistance.

[Purpose of the invention] This invention was made based on the above-mentioned circumstances.

That is, this:5i! The purpose of II Shell is to solve the above-mentioned problems in the production method of polycarbonate J''i combination using bisphenol such as bisphenol A, bisphenol sulfone, and phosgene as raw materials, and to increase the sulfone content and have excellent oil resistance. Furthermore, it is possible to easily and efficiently produce a polycarbonate copolymer having transparency and mechanical properties comparable to those of conventional copolymers.An object of the present invention is to provide a novel method.

As a result of extensive research into a method for producing a polycarbonate copolymer with increased oil resistance by increasing the sulfone content, the inventors found that a specific stepwise polymerization method was developed without using a quaternary ammonium salt. By using this, there are no problems such as generation of emulsions or phase separation, and
The present invention was achieved by discovering a new method capable of producing a polycarbonate copolymer with a high sulfone content.

[Efforts to solve the above problems] The outline of the present invention for solving the above problems is to provide a method for producing a polycarbonate copolymer using bisphenols, bisphenolsulfones, and phosgene as raw materials. A method for producing a polycarbonate copolymer, which comprises reacting a mixture of and bisphenolsulfones with phosgene to produce a cooligomer, and then reacting the cooligomer with bisphenols and/or bisphenolsulfones. It is.

The bisphenols have the linear [1] formula.

(However, in Shiki No. 11, X is a single bond, Cl-C
8 alkylene group, 02-C8 fullkenylene group or alkylidene group, cyclohexylene group, cyclohexenylene group, cyclohexylidene group, etc. having 8 or more carbon atoms
represents a divalent hydrocarbon group or s, o, or co (carbonyl group), R represents a chlorine atom, a bromine atom, or an alkylno S having 1 to 3 carbon atoms, p and p' are each an integer of θ to 2 means.

In addition, it is preferable that the position of the substituent R is at the ortho position with respect to the hydroxyl group, and R may be the same type or different types. As a specific example, for example,
biphenyl-4,4'-diol, 3,5.3', 5
'-tetotehydroxybiphenyl; bis(4-hydroxyphenyl)methane, 1,2-bis(4-hydroxyphenyl)ethane, 1.1-bis(4-hydroxyphenyl)ethane, 1.3-bis(4-hydroxy phenyl)
Propane, 1.2-bis(4-hydroxyphenyl)propane, 1.1-bis(4-hydroxyphenyl)propane, 2.2-bis(4-hydroxyphenyl)propane (ff11 name: bisphenol A), 1. 1-bis (4
-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)butane, l,4-bis(4-hydroxyphenyl)butane, 3,3-bis(4-hydroxyphenyl)pentane, 2,2-bis (4-hydroxyphenyl)butane, 2,2-bis(3,5-dimethyl-4
゛ -Hydroxyphenyl)propane (also known as tetramethylbisphenol A), 2,2-bis(3-methyl-
Bis(4-hydroxyphenyl)alkanes such as 4-hydroxyphenyl)propane and 2-(hydroxyphenyl)-2-(3-methyl-4-hydroxyphenyl)propane: l,2-bis(hydroxyphenyl)ethylene, etc. bis(4-hydroxyphenyl) alkenes; 1,
4-bis(4-hydroxyphenyl)cyclohexane,
1.4-bis(4-hydroxyphenyl)cyclohexene; 2.2-bis(3,5-dichloro-4-hydroxyphenyl)propane (also known as tetrachlorobisphenol A), 2,2-(3,5-dibromo) -4-hydroxyphenyl)propane (also known as tetrabromobisphenol A), 2,2-bis(3-chloro-4-hydroxyphenyl)propane, 2-(3,5-dichloro-4
-hydroxyphenyl)-2-(4-hydroxyphenyl)propane, 2,2-bis(3-chloro-4-hydroxy-5-methylphenyl)propane, 2,2-bis(
Bis(substituted-4-hydroxyphenyl)flucanes such as 3-bromo-4-hydroxyphenyl)propane
4-hydroxyphenyl ethers such as 4-hydroxyphenyl)ether and di(3,5-dimethyl-4-hydroxyphenyl)ether; 4-hydroxyphenylthioethers such as di(4-hydroxyphenyl)thioether 9n di(4- Examples include di(4-hydroxyphenyl)ketones such as hydroxyphenyl)ketone. Among these, 2,2-bis(4-hydroxyphenyl)propane (also known as bisphenol A)
is particularly suitable.

These can be used alone or in combination of two or more.

The bisphenol sulfones are represented by the following formula [2].

(However, in the above formula [2] 1, R° represents an elementary atom, a bromine atom, an alkyl group having 1 to 4 carbon atoms, q,
q' each means an integer of 0 to 2. In addition, the above Z
It is preferable that the potential of tJlllJ&R'' is at the ortho position with respect to the hydroxyl group.

are compounds that are different types even if they are in the same category.

Specific examples include di(4-hydroxyphenyl)sulfone (also known as bisphenol sulfone), di(3,5-
dimethyl-4-hydroxyphenyl) sulfone (also known as:
tetradimethylbisphenol sulfone), di(3,5
-dichloro-4-hydroxyphenyl) sulfone (also known as tetrachlorobisphenol sulfone), di(3,5
-dibromo-4-hydroxyphenyl) sulfone (also known as tetrabromobisphenol sulfone). Among these, di(4-hydroxyphenyl)sulfone is particularly preferred.

In addition, these bisphenol sulfones.

One type can be used alone or two or more types can be used in combination.

In the method of the present invention, in the presence of an aqueous solution of an alkaline compound and an organic solvent, the bisphenols (hereinafter, this may be referred to as the [A] acid component) and the bisphenolsulfones (hereinafter, this may be referred to as [A] acid component), B] Jji,
Sometimes called minutes. ) and phosgene (COCJ12)
are reacted (condensed) to form a cooligomer. (Hereinafter, this step may be referred to as the first reaction step.) The alkaline compound is water-soluble and has a strong a! Basic alkali metal compounds and alkaline earth compounds can be used. Among others.

Alkali metal hydroxides are preferred, and sodium hydroxide is particularly preferred.

Examples of the organic solvent include dichloromethane (methylene chloride), trichloromethane (chloroform), tetrachloromethane, dichloroethane, dichloroethane, dichloroethylene, trichloroethylene, chlorobenzene, dichlorobenzene, chlorotoluene, etc. Inert organic solvents such as hydrogen, dioxane, cyclic oxy compounds such as tetrahydrofuran, etc. can be used. Among these, methylene 111 is particularly suitable.

In the first reaction, the cooligomer produced has an average degree of polymerization of 1, usually 2 to 2G.

Preferably, it is set to 2-4. The structure of the cooligomer can be expressed by the following formula [3] according to the usual convenient general formula representation method (however, the structure [3]
In the formula, R, X, R', p.

p', q, and q' have the same meanings as above.

n and m each mean an integer of 0 or more, and (n
+ m) is 1 usually 2 to 30. Preferably it is 2-4. ) If the average degree of polymerization or the value of (n+m) is outside the above range, the desired sulfone-rich polycarbonate copolymer may not be obtained, or the cooligomer may be difficult to separate. be.

In order to produce the cooligomer, the blending ratio of each component is as follows.

That is, the blending ratio of the [A] acid component and [B] acid component is 0 to 80 moles of the [B] acid component when the sum of [A] m and [B] acid component is 109 mol%. % (therefore, the [A] acid component is 100 to 20 mol%), preferably 0 to 50 mol% (therefore, the [A] acid component is 100 to 50 mol%). Set. [B] If the acid component exceeds 80 mol %, the resulting oligomer may contain substances that are insoluble in the solvent, which is not preferable.

The machine for using the alkali compound is 1. Usually, the machine for using the alkali compound is
The amount is set to be at least the amount (stoichiometric amount) that neutralizes all the phenolic hydroxyl groups in component A] and component [B], preferably 1.1 to 1.8 times the amount of the phenolic hydroxyl group.

For example, if the alkaline compound is 1 such as sodium hydroxide,
In the case of alkaline compounds of high valence, their usage (number of moles)
is at least twice the usual total amount (total number of moles) of [A] acid component [B] acid component used, preferably 2.2 to 3.9
shall be.

The alkali compound is usually used as an aqueous solution.

The age of the trees constituting the alkaline compound aqueous solution during the reaction (i.e., the total 11 cm of water used to prepare the reaction system) is the total amount of the [A] acid component and [B] acid component!
Normally, the amount is set to 300 to 1,000 parts per side, preferably 9 parts by weight of 500 to 700 parts.

The usage fee for the organic solvent is 100 parts by weight of the total amount of the acid component [A] and [B] acid component, usually 300 to 30 parts by weight.
part, preferably in the range of 400 to 500 parts.

The oligomer is prepared by mixing the [A] acid component such as bisphenol A, the [B] acid component such as bisphenol sulfone, the alkali compound aqueous solution such as a sodium hydroxide aqueous solution, and the organic solvent such as methylene chloride in the above blending ratio (mixing).
It can be produced by preparing a liquid mixture and bringing the liquid mixture into contact with phosgene.

There are no particular restrictions on the order or method of blending each component to make the above-mentioned mixed solution 7A, but usually, first, [A] I & Min and [B] an aqueous solution of an alkali compound as an acid component are blended, and then A method of adding an organic solvent to the solution is preferably used.

As the method of contacting the blended solution with phosgene, a method is preferably used in which phosgene is introduced into the blended solution by blowing it into the blended solution while stirring the blended solution. At this time, the supply rate of phosgene is usually about 100 to 500 m11 minutes, preferably 2
It should be about 00 to 300 meters long.

By introducing this phosgene, the mutual sulfurization reaction proceeds, but when the pH of the reaction system (blended solution) reaches a range of 9 to 12, the introduction (blowing) of phosgene is stopped.

The temperature when preparing the above-mentioned liquid mixture is usually lθ~80°C,
Preferably it is 20-30°C.

The temperature at which the phosgene is introduced, that is, the reaction temperature for producing the cooligomer, is usually 0 to 50°C,
Preferably it is 30-40°C.

In addition, during the reaction, if necessary, in the mixed solution,
A cooligomer can also be produced by coexisting a known molecular weight regulator.

Examples of the molecular weight regulator include □methanol,
Alcohols such as ethanol, isopropyl alcohol, and butanol; and phenols such as phenol, cresol, butylphenol, and p-tert-butylphenol. Among these, P-tert-butylphenol and the like are particularly preferred.

In addition, during the reaction, Jiffi the blending ratio of each component such as the ratio of the [AI acid component to the [B] acid component,
By controlling the reaction conditions, the molecular weight y
It is also possible to arbitrarily adjust the molecular weight of the cooligomer produced and the sulfone content in the cooligomer by selecting the am agent, the A section of the needle used, etc.

After the introduction of phosgene is stopped and the reaction is interrupted, the reaction product solution is allowed to stand, phase-separated into an aqueous layer and an organic layer, and the organic layer is collected.

By producing the cooligomer as described above, no emulsion is generated in the reaction product liquid, and the aqueous layer and aqueous layer are separated.
Phase separation with MI becomes extremely easy.

Note that the target cooligomer can be recovered in good yield as a component in the a-layer.

Next, a method for producing a polycarbonate copolymer by reacting bisphenols and/or bisphenol sulfone of the cooligomer will be described.

In the method of the present invention, the cooligomer and the [A] acid component or the [B] acid component are combined in the presence of the aqueous solution of the alkaline compound, the organic solvent, the catalyst, and optionally the molecular weight regulator. or the [A] acid component and the [A] acid component;
81 components to perform a single polycondensation reaction (interfacial polycondensation), a bricarpone composite is produced (this step may be referred to as the second reaction step hereinafter). The organic layer recovered in the first reaction step can be used as is as part of the cooligomer and organic solvent used in the second reaction step. Also, the second
The aqueous solution of the alkaline compound, the organic solvent, the [A] acid component, the [B] acid component, and the molecule 14 JRm agent used in the reaction step may each be the same type as that used in the first reaction step. However, as in the first reaction step, sodium hydroxide aqueous solution, methylene chloride, bisphenol A, bisphenol sulfone, and p-tart-butylbenzene are preferred for each component. It's a monkey.

In the second reaction step. The blending ratio of each component is
It is as follows.

That is, the amount of the [A] acid component and/or the [B] acid component used is 100 fr! of the cooligomer! .

Per 1g of amount, the total amount of [A] acid component [B]
It is usually set at 15 to 38 parts, preferably 21 to 29 parts. However, the ratio of the AI acid component to the total amount of the A1 component and the acid component B can be in the range of 0 to 100%.

The C degree of the aqueous solution of the alkaline compound is usually 1.9 to
3°3 normal, preferably 1.7 to 2.5 normal.

The amount of the alkaline compound aqueous solution used is usually set at 100 to 300 parts by weight, preferably 150 to 180 parts by weight, per 100 parts by weight of the cooligomer.

The amount of the organic solvent used is usually 150 to 300 parts by weight, preferably 2 parts by weight, per 100 parts by weight of the cooligomer.
The amount is set at 10 to 240 parts by weight. However, when the organic layer containing the cooligomer is used, this usage amount includes the amount of the organic solvent in the organic layer.

The amount of the molecular weight modifier to be used cannot be uniformly prescribed because it varies depending on the type, reaction conditions, and other various conditions, but it is usually 1.0 parts per 100 parts of the cooligomer.
~4-0 rabbit parts, preferably.

The amount is 2.0 to 2.5 parts by weight.

Examples of the catalyst include conventional polycarbonate or polycarbonate copolymer production methods ( Examples include known catalysts that can be used in the phosgene method). Among these, triethylamine is particularly preferred. In addition to the compounds exemplified above, quaternary ammonium salts are known as the known catalysts, and these quaternary ammonium salts can also be used as catalysts. .

However, when this quaternary ammonium salt is used as a catalyst, the reaction rate of the polycondensation reaction may not reach a practical level.

The reaction temperature of the polycondensation reaction is usually 10 to 80°C,
Preferably, the temperature is set at 30 to 40°C. Note that this reaction can be suitably carried out at room temperature.

The reaction time is usually 30 minutes to 180 hours, preferably 80 minutes to 120 hours.

In carrying out the 1t1 subcondensation reaction, there is no particular restriction on the reaction operation method used, and for example, a batch method, a continuous method, etc. can be used. In any reaction operation method, it is desirable that the aqueous layer and organic layer constituting one reaction system come into contact with each other efficiently, so it is preferable to stir the reaction system sufficiently. Polycondensation reactions can be carried out efficiently.

Since the copolymer produced as described above is contained in the Ja-containing layer, the aqueous layer and the aP-containing layer are separated by layer separation, and the organic layer containing the copolymer is recovered. The recovered a-layer is washed with water and acid until it becomes neutral or near neutral, and then the water and organic layer are separated again using phase separation #, etc., and the generated organic layer is collected. The desired copolymer (polycarbonate copolymer) can be obtained by distilling off the solvent or adding a precipitant.

In addition, even at the stage of the m-condensation reaction, the formulation regulation of the [B]r& component such as bisphenol sulfone is changed to i3!
1m, the sulfone content in the copolymer is
Can be adjusted over a wide range.

With the method of the present invention, a copolymer with a high sulfone content can be easily produced compared to conventional methods.

By increasing the sulfone content, the heat resistance, gasoline resistance, and other oil resistance of the copolymer can be significantly improved. However, for gasoline resistance, it is preferable that the sulfone content of the copolymer is usually in the range of 10 to 40 mol%, and even if the content exceeds 40 mol%, further improvement in gasoline resistance is expected. Can not.

The polycarbonate copolymer produced by the above method is
If necessary, stabilizers, plasticizers, and organic/inorganic fillers may be added and molded into various shapes, such as various industrial parts such as automobiles and home appliances, tableware, containers, medical equipment, etc. It can be used for various purposes.

Regarding the moldability of copolymers, in general, as the sulfone content increases, fluidity tends to decrease.

Therefore, as a self-weighted polycarbonate copolymer that maintains the moldability of polycarbonate (polycarbonate) 1 and has heat resistance and gasoline resistance, for example, a sulfone content of 10
It is preferable to set the content to about 15 to 30 mol%, preferably about 15 to 30 mol%.

[Effects of the Invention] According to the present invention, a polycarbonate copolymer having a higher sulfone content can be produced compared to conventional methods.

That is, according to the method of the present invention, there is no generation of emulsions and phase separation is possible, so that the cooligomer can be easily separated from the aqueous layer, so that a copolymer with a high sulfone content can be efficiently obtained. .

Also, the sulfone content in the copolymer can be adjusted virtually arbitrarily. Since the sulfone content can be increased, a polycarbonate copolymer with significantly improved heat resistance can be easily produced. In addition, since the sulfone content can be adjusted over a wide range, it has excellent heat resistance.

Polycarbonate copolymers with significantly improved gasoline resistance can be produced. Furthermore, since the sulfone content can be easily controlled, it is possible to easily produce a polycarbonate copolymer that has excellent heat resistance and gasoline resistance, and has good processability.

The polycarbonate copolymer produced by the method of the present invention does not impair the properties of conventional polycarbonate (transparency: 1 mechanical: 9-).

[Example] (Example 1) Production example of polycarbonate copolymer containing 20 mol% of sulfone 131.8 g of bisphenol A, 48.2 g of bisphenol sulfone, 1020 ml of 13.10% aqueous sodium hydroxide solution, 600 m of methylene chloride
After charging into the reactor of love, p at Phosdef 250m1/min
Blow was carried out until H9 was reached to produce a cooligomer.

(Bisphenol/bisphenol: 75/25
(Molar ratio)) Subsequently, the organic layer and the aqueous layer were separated, and the organic layer and the aqueous layer were separated. j273
+nl (oligomer concentration 3 to g/l) was collected and added with 19.8 g of bisphenol A, 130 mJL of 8.10% aqueous sodium hydroxide solution, and 177 m of methylene chloride.
0.039 g of triethylamine and 1.8 g of pt-butylphenol were charged into a 1 fL □ reactor and stirred at room temperature for 60 minutes to perform interfacial polycondensation.

After that, the organic layer and the aqueous layer were separated, and the organic layer was washed with dilute hydrochloric acid and water according to the usual procedure until the washing solution became neutral.
Thereafter, the solvent in the a-layer was evaporated and dried to obtain a polycarbonate copolymer.

After crushing the obtained copolymer, it was tested by injection molding.

Pieces were prepared and their 1M physical properties were measured. The results are shown in Table 1.

(Example 2) Polycarbonate copolymer bisphenol A containing 40 mol% of sulfone 73.3 g, bisphenol sulfone 98.4 g, 8.23% sodium hydroxide aqueous solution 10
Example 1 from 20 ml, 600 mJl of methylene chloride
Cooligomers were produced in the same manner as in . (Bisphenol/
Bisphenol sulfone 5G15G (molar ratio)) Subsequently, the organic layer and the aqueous layer were separated, and 273 mfL of the organic layer (oligomer concentration 317 g/u) was collected, and this was added with 9.8 g of bisphenol AI and 8.10% sodium hydroxide. 130 mJL of an aqueous solution, 177 m of fluorinated methylene, 0.039 gt of triethylamine, and 2.2 g of pt-butylphenol were charged into a 141 reactor and stirred at room temperature for 130 minutes to perform interfacial qrm combination. The results are shown in Table 1.

(Example 3) Polycarbonate copolymer containing 40 mol% of sulfone 273 mJL of cooligomer solution obtained in Example 1 (oligomer concentration 310 g/mu) Bisphenol, 21.5 g of sulfone, 128 m of 8.21% aqueous sodium hydroxide solution 177 mjL of methylene chloride, 0.077 g of triethylamine, and 2.2 g of p-t-butylphenol were charged into a reactor No. 11, and the mixture was stirred at room temperature for 130 minutes to perform interfacial polycondensation. The results are shown in Table 1.

(χ flow side 4) Polycarbonate copolymerization containing 60 mol% of sulfone Cooligomer obtained in Example 2 273 rnl (oligomer 6 degree 3ty g/mi) Bisphenol sulfone 21
．． 5g, 128ml of 8.21% aqueous sodium hydroxide solution
1. methylene methylene 17? mJL,) ethylamine 0.
077 g, p-t-butylphenol 2.8
g into a ti reactor, stirred at room temperature for 80 minutes,
Interfacial polycondensation was performed. The results are shown in Table 1.

(Comparative Example 1) Bisphenol Al 31.8 g, bisphenol sulfone 48.2 g, 8.1% sodium hydroxide aqueous solution 10
20 m cross, 3.7 g of pt-butylphenol, 0.081 g of triethylamine, 800 ml of methylene chloride
After charging the reactor, the pH was controlled at 13 during the zero reaction in which phosgene was blown in at a rate of 250 m/min. After 2 hours, the blowing of phosgene was stopped to complete the first reaction. Even though methylene chloride was added to the resulting suspension and the mixture was leveled for 5 hours, the organic layer and aqueous layer did not separate and remained in an emulsion state.

(Comparative Example 2) Bisphenol Al 80 g, 8.1% sodium hydroxide aqueous solution 1020 m, methylene chloride 809 mu 2
After charging the reactor, phosgene was blown in at 250 ml/min until the pH reached 9 to generate oligomers.

Subsequently, the organic layer and the aqueous layer were separated, and 273 ml of the organic layer (oligo concentration 310 g/l) was collected, and this was added with 30.0 g of bisphenol sulfone, 120 tnl of a 12.3% aqueous sodium hydroxide solution, and methylene chloride. 177m1,
Triethylamine 0.078 g, p-t-
Butylphenol t, sg was charged into a 14 reactor and stirred at room temperature for 80 minutes to perform interfacial polycondensation.

Thereafter, methylene chloride was added to try to separate the organic layer and the aqueous layer, but they did not separate and remained in an emulsion state.

Procedural amendment (voluntary) 1 Indication of the case Patent Application No. 90953 of 1985 2 Name of the invention Process for producing polycarbonate copolymer 3 Person making the amendment Relationship with case 41G Patent applicant address Marunoshiratama, Chiyoda-ku, Tokyo Chome 111 FI No. 4
Address of agent: 5-5 Nishi-Shinjuku 8-chome, Shinjuku-ku, Tokyo Number of inventions increased by amendment: None 8. Contents of amendment (1) “Tetradimethylbisphenol sulfone” described in the second line from the bottom of page 9 of the specification " is corrected to "tetramethylbisphenol sulpon."

(2) "Butylbenzene" written on page 18, line 7 of Ming Zhu is corrected to "butylphenol."

(3) "Trimylamine" described on page 19, line 15 of the specification is corrected to "trimethylamine."

−1 above

Claims (3)

[Claims] (1) Bisphenols, bisphenol sulfones,
and a method for producing a polycarbonate copolymer using phosgene as a raw material, in which a mixture of bisphenols and bisphenolsulfones is reacted with phosgene to produce a cooligomer; 1. A method for producing a polycarbonate copolymer, the method comprising reacting a polycarbonate copolymer with a polycarbonate copolymer. (2) The method for producing a polycarbonate copolymer according to claim 1, wherein the bisphenol is bisphenol A. (3) Claim 1 or 2, wherein the bisphenol sulfone is bisphenol sulfone.
The method for producing a polycarbonate copolymer described in 2.