TW201311762A - Method for continuously producing branched polycarbonate - Google Patents

Abstract

This invention provides a method for continuously producing branched polycarbonate containing (A) a step of producing a low molecular weight polycarbonate having a number-average molecular weight of 1000 to 10000 from an aromatic di-hydroxy compound and diester carbonate by an ester exchanging method, (B) a step of adding and mixing the multi-functional compound with liquid state in the low molecular weight polycarbonate, and (C) a step of continuously performing a polymerization reaction till the melt index of the low molecular weight polycarbonate becomes 10g/10min or lower and the branch index becomes 14 or more, to produce branched polycarbonate.

Description

Continuous manufacturing method of branched polycarbonate

This invention relates to a continuous process for the manufacture of branched polycarbonates using the transesterification process.

Polycarbonate is an engineering plastic with excellent mechanical strength such as transparency, heat resistance and impact strength. It has been widely used in industrial applications such as optical discs and electrical appliances, and automobiles. Among them, in recent years, large-scale bottling by blow molding has been widely used because of its design and toughness which is not easily broken even if it is dropped, and is used for providing drinking water and specific in countries without tap water conveying equipment. Mineral water delivery from the place of origin.

However, in order to stably perform such blow molding of such a large bottling, it is required to have a higher melt viscosity and a melt tension than a polycarbonate which is generally used. Therefore, in order to make it polymerizable and have a branched structure in a molecule, it is necessary to raise the melt tension of polycarbonate. However, in the phosgene method which has been used for a long time in the production method of polycarbonate, as in Patent Document 1, a polyfunctional compound is used as a branching agent to solve the problem of forming a branched structure of polycarbonate. . However, since the phosgene method uses highly toxic carbon dichloride and a large amount of a chlorine-containing solvent, the load on the environment is large. In response to this, in recent years, the awareness of environmental issues has risen, and the manufacturing method of polycarbonate has been converted to a transesterification method that does not use carbon dichloride and a large amount of chlorine-containing solvent. However, since the industrial continuous manufacturing process of branched polycarbonate which is currently carried out by the transesterification method is still in the development stage, many proposals are still needed to be improved.

Among them, the transesterification method is a method in which an aromatic dihydroxy compound, diphenyl carbonate, and a polyfunctional compound as a branching agent are melt-reacted in the presence of a catalyst, whereby a branched polycarbonate can be obtained. However, industrially, it is not easy to produce a good branched polycarbonate by a simple reaction. Therefore, in order to improve this situation, the following methods [1] to [3] have been proposed.

[1] A method of using a specific catalyst to reduce the Kolbe-Schmitt branching structure naturally occurring during the melting reaction (Patent Documents 2 to 4), and using a specific catalyst to improve A method of a hue (Patent Document 5), and a method of using a polyfunctional compound having a specific structure as a branching agent (Patent Documents 6 to 8).

[2] A method of adding a branching agent made of a polyfunctional compound and a transesterification catalyst to a polycarbonate which has been produced, and performing a reaction in an extruder to obtain a branched polycarbonate (Patent Document 9 to 11).

[3] A method for producing a branched polycarbonate which can actively produce a naturally occurring branched structure during the polymerization reaction without using a branching agent which is a cause of step contamination (Patent Documents 12 and 13).

[Previous Technical Literature] Patent literature:

[Patent Document 1] Japanese Patent Publication No. Sho 47-23918

[Patent Document 2] Japanese Patent Laid-Open No. 5-271400

[Patent Document 3] Japanese Patent Laid-Open No. Hei 5-271402

[Patent Document 4] Japanese Patent Laid-Open No. Hei 5-295101

[Patent Document 5] Japanese Patent Laid-Open No. Hei 4-89824

[Patent Document 6] Japanese Patent Laid-Open Publication No. 2001-302780

[Patent Document 7] Japanese Patent Publication No. 2002-508801

[Patent Document 8] Japanese Patent Laid-Open Publication No. 2006-131910

[Patent Document 9] Japanese Laid-Open Patent Publication No. 02-245023

[Patent Document 10] Japanese Patent Laid-Open No. Hei 11-209469

[Patent Document 11] Japanese Patent Laid-Open Publication No. 2000-290364

[Patent Document 12] Japanese Patent Laid-Open Publication No. 2002-308976

[Patent Document 13] Japanese Patent Laid-Open Publication No. 2004-002831

However, the polycarbonate produced by the production method [1] can improve the hue, but produces many fish-eyes and is inferior in hot water resistance. Further, since the branching agent is added together with the aromatic dihydroxy compound and diphenyl carbonate in the production step of the linear polycarbonate, when the raw material is a linear polycarbonate by the branched polycarbonate Later, the linear polycarbonate produced will produce fish eyes. In order to eliminate such adverse effects, there is a problem that it takes a long time to replace the raw materials, or it is necessary to clean the production equipment when the production is temporarily stopped.

Further, in the production method [2], although the above-mentioned problem occurring in the replacement of the raw material can be eliminated without adding a branching agent in the polymerization step, it can be seen that many fish eyes are produced in the produced branched polycarbonate. Since the hot water resistance is also lowered, there is a problem that polycarbonate of a good quality cannot be stably formed.

Further, in the production method [3], although there is an advantage that it is not necessary to add a branching agent, since the side reaction of the rearrangement reaction is actively caused, it is difficult to manufacture stably, and in addition, an unnecessary side reaction may be caused. There are problems such as deterioration of hue, generation of many fish eyes, and reduction of other hot water resistance, and there is also a problem of loss when replacing raw materials.

Accordingly, the present invention has been made in view of the above circumstances, and an object thereof is to provide a continuous production method of a branched polycarbonate which can reduce loss when replacing raw materials in the production of branched polycarbonate by a transesterification method, and at the same time, excellent color and hot water resistance, fish eyes There are also few.

The continuous production method of the branched polycarbonate provided by the present invention comprises: (A) preparing a low molecular weight polycarbonate having a number average molecular weight of 1,000 to 10,000 by transesterification from an aromatic dihydroxy compound and a carbonic acid diester. And a step (B) of adding and mixing a polyfunctional compound in a liquid state to the low molecular weight polycarbonate, and (C) continuing until the melt index of the low molecular weight polycarbonate is 10 g/10 min or less and the branch index becomes The polymerization reaction is carried out until 14 or more to form a branched polycarbonate. In this way, when the branched polycarbonate is continuously produced by the transesterification method, not only the loss in the replacement of the raw material but also the color and the hot water resistance are excellent, and the fisheye is also small.

Further, in the present invention, the range of ΔT (°C) defined by the following formula (I) is preferably -20 ° C to 20 ° C or less. In this case, the above effects of the present invention can be more exerted.

ΔT=T ₂ -T ₁ (I)

Wherein T ₁ represents the temperature (° C.) of the low molecular weight polycarbonate introduced into the final polymerization vessel in the above step (C); T ₂ represents the branching polymerization by the aforementioned final polymerization polymerization in the aforementioned step (C) The temperature of the carbonate (° C.) and T ₂ is 285 ° C or lower. ]

The above-mentioned polyfunctional compound is preferably added to a melt mixer which is provided in the middle of the piping between the apparatus for carrying out the step (A) and the apparatus for carrying out the step (C) in a state of being dissolved in a solvent. Thereby, the above effects of the present invention can be further exerted.

Further, the solvent is a mixture of a phenol, a carbonic acid diester, a ketone, an ether, a mixture of an aromatic dihydroxy compound and a carbonic acid diester, and a reactant, and a low molecular weight polycarbonate having a number average molecular weight of 5,000 or less. It is preferred to select at least one of the groups. Thereby, the above effects of the present invention can be further exerted.

Further, the above solvent is preferably a depolymerization solvent. Thereby, the above effects of the present invention can be further exerted. Moreover, the term "depolymerization solvent" as used herein means a solvent which causes a depolymerization reaction of polycarbonate.

Meanwhile, the present invention preferably further comprises, after the step (A), a step of producing a polycarbonate which is subjected to a polymerization reaction until the melt index is 100 g/10 min or less. According to this manufacturing method, a plurality of polycarbonates including a branched polycarbonate can be continuously produced by a transesterification method, and the branched polycarbonate can reduce loss in replacement of raw materials, and has excellent hue and hot water resistance and less fish eyes. .

The apparatus for performing the step (A) is carried out by means of a device capable of performing the step (C) and a device having the branched portion in the step (D), and the device performing the step (C) The apparatus of the step (D) is connected so that the above polyfunctional compound can be added to a melt mixer provided in the middle of the piping between the branching portion and the apparatus for performing the step (C). Thereby, the above effects of the present invention can be further exerted.

The present invention further provides a branched polycarbonate produced by the above method. The branched polycarbonate is excellent in hue and hot water resistance and has few fish eyes.

According to the continuous production method of the branched polycarbonate provided by the present invention, when the branched polycarbonate is produced by the transesterification method, the loss at the time of replacement of the raw material can be reduced, and the hue and hot water resistance are excellent and the fish eyes are small.

The invention will be described in detail below. In the continuous production method of the branched polycarbonate of the present embodiment, the aromatic dihydroxy compound, the diphenyl carbonate, and the polyfunctional compound can be converted into a branched polycarbonate by a transesterification method.

The aromatic dihydroxy compound in the present embodiment may, for example, be a compound represented by HO-Ar-OH. Wherein Ar is a divalent aromatic residue, and examples thereof include a diphenyl group represented by a stretching phenyl group, an anthranyl group, a stretched biphenyl group, a stretched pyridyl group, or an -Ar ¹ -Y-Ar ² - group. Family residue. Wherein, Ar ¹ and Ar ^{2 are} each independently, and represent an aryl group having a carbon number of 5 to 70 divalent carbocyclic or heterocyclic ring; and Y represents a divalent alkylene group having 1 to 30 carbon atoms.

In the above-mentioned divalent aryl group (Ar ¹ , Ar ² ), one or more hydrogen atoms bonded to the aromatic ring may have other substituents, such as carbon number 1 to 1, without adversely affecting the reaction. An alkyl group of 10, a cycloalkyl group having a carbon number of 5 to 10 constituting a ring, an alkoxy group having 1 to 10 carbon atoms, a phenyl group, a phenoxy group, a vinyl group, a cyano group, an ester group, a decylamino group, and a nitrate Substituted by the base. Specific preferred examples of the heterocyclic aryl group include a heterocyclic aryl group having one or a plurality of nitrogen atoms, oxygen atoms or sulfur atoms in the ring.

Ar ¹ and Ar ² each preferably have a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted pyridine group, and the like.

The divalent alkyl group Y may, for example, be an organic group represented by the following formula.

(wherein R ¹ , R ² , R ³ and R ^{4 are} each independently, and represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and a carbon number of 5 to 10 a cycloalkyl group of 10, a carbocyclic aryl group having a carbon number of 5 to 10, or a carbocyclic aryl group having 6 to 10 carbon atoms, k representing an integer of 3 to 11; and R ⁵ and R ⁶ for each X For individual selection, represent mutually independent hydrogen atoms or alkyl groups having 1 to 6 carbon atoms; X represents carbon. Further, of R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , more than one hydrogen The atom may have other substituents in the range which does not adversely affect the reaction, such as an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a phenyl group, a phenoxy group, a vinyl group, and a cyano group. , ester, amidino, nitro, etc. substitution.)

The divalent aromatic residue Ar having a substituent as described above may, for example, be a compound represented by the following formula.

(wherein R ⁷ and R ^{8 are} each independently, and represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms constituting the ring or Phenyl; m and n represent an integer from 1 to 4, and when m is from 2 to 4, each R ⁷ may be the same or different, and when n is from 2 to 4, each R ⁸ may be the same or different.

Meanwhile, the divalent aromatic residue Ar may be a compound represented by -Ar ¹ -Z-Ar ² -. Ar ¹ and Ar ² are the same as described above; Z represents a single bond or a 2-valent such as -O-, -CO-, -S-, -SO ₂ -, -SO-, -COO-, -CON(R ¹ )-, etc. The basis. The R ¹ system is the same as described above.

The bivalent aromatic residue Ar may be a compound represented by the following formula.

(wherein R ⁷ , R ⁸ , m and n are the same as described above.)

The aromatic dihydroxy compound used in the present embodiment may be used alone or in combination of two or more. Representative examples of the aromatic dihydroxy compound include bisphenol A, and when used together with other aromatic dihydroxy compounds, the amount of bisphenol A used relative to the total amount of the aromatic dihydroxy compound used. It is preferable to use a ratio of 85 mol% or more. Further, such an aromatic dihydroxy compound is preferably one in which the chlorine atom and the alkali metal or alkaline earth metal are contained in a small amount, and it is preferred that the aromatic dihydroxy compound is substantially free of such a substance.

The carbonic acid diester used in the present embodiment may, for example, be a compound represented by the following formula.

(In the formula, each of Ar ³ and Ar ⁴ represents a monovalent aryl group.)

Preferable examples of Ar ³ and Ar ⁴ of the monovalent aryl group include a phenyl group, a naphthyl group, a biphenyl group, and a pyridyl group. In Ar ³ and Ar ⁴ , one or more hydrogen atoms bonded to the aromatic ring may have other substituents without adversely affecting the reaction, such as: an alkyl group having 1 to 10 carbon atoms, and a carbon number of 1 Substituted to alkoxy, phenyl, phenoxy, vinyl, cyano, ester, decyl, nitro, and the like. Among them, Ar ³ and Ar ⁴ may be the same or different from each other.

More preferable examples of Ar ³ and Ar ⁴ include the groups shown by the following formulas.

Representative examples of the carbonic acid diester include substituted or unsubstituted diphenyl carbonates represented by the following formulas.

(wherein R ⁹ and R ^{10 are} each independently, and represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms constituting the ring or Phenyl; p and q represent an integer of 1 to 5, and when R is 2 or more, each R ⁹ may be different, and when q is 2 or more, each R ¹⁰ may be different.)

Among the above-mentioned carbonic acid diesters, symmetrical types such as unsubstituted diphenyl carbonate and diphenyl carbonate substituted by a lower alkyl group such as ditolyl carbonate and di(t-butylphenyl) carbonate Diaryl carbonate is preferred, and diphenyl carbonate is preferred. These carbonic acid diesters may be used singly or in combination of two or more kinds. Further, such a carbonic acid diester is preferably one in which the content of the chlorine atom and the alkali metal or alkaline earth metal is small, and if it is possible, it is preferably not substantially contained.

The ratio (addition ratio) of the aromatic dihydroxy compound to the carbonic acid diester differs depending on the type of the aromatic dihydroxy compound and the carbonic acid diester to be used, the molecular weight of the target, the ratio of the hydroxyl group terminal, and the polymerization conditions. However, there is no particular limitation. The ratio of the carbonic acid diester to the 1 mole of the aromatic dihydroxy compound is preferably 0.9 to 2.5 moles, more preferably 0.95 to 2.0 moles, still more preferably 0.98 to 1.5 moles. Further, in the case of terminal transformation and molecular weight adjustment, an aromatic monohydroxy compound may also be used in combination.

The polyfunctional compound used in the present embodiment is a compound containing three or more functional groups reactive with a carbonic acid diester in the molecule, and a compound containing three or more phenolic hydroxyl groups and/or carboxyl groups is preferred. . Examples of the polyfunctional compound include 1,1,1-paraxyl(4-hydroxyphenyl)ethane and 4-[4-[1,1-indolyl(4-hydroxyphenyl)ethyl]-α. ,α-xylylenemethyl]phenol, 2,2',2"-parade (4-hydroxyphenyl)diisopropylbenzene, α,α',α"-parade (4-hydroxyphenyl)triisopropyl Benzene, phloroglucinol, 4,6-dimethyl-2,4,6-tris(4-hydroxyphenyl)heptane-2, 1,3,5-tris(4-hydroxyphenyl)benzene, 2,2'-贰-[4,4-(4,4'-dihydroxydiphenyl)cyclohexyl]-propane, α-methyl-α,α',α'-para (4-hydroxyphenyl) )-1,4-diethylbenzene, tris-(4-hydroxyphenyl)phenylmethane, 2,4-bis(4-hydroxyphenylisopropyl)phenol, 2,6-di(2-hydroxy-5) '-Methylbenzyl)-4-methylphenol, 2-(4-hydroxyphenyl)-2-(2,4-dihydroxyphenyl)propane, hexa-(4-(4-hydroxyphenyl) Propyl)phenyl)-terephthalate, tetra-(4-hydroxyphenyl)methane, tetra-(4-(4-hydroxyphenylisopropyl)phenoxy)methane, 1,4-two (4',4"-dihydroxy-triphenyl)toluene, 2,4-dihydroxybenzoic acid, trimesic acid, 3,3-bis(3-methyl-4-hydroxyphenyl)-2- Oxy-2,3-dihydroindole, benzotrimethyl chloride, α,α',α"-gin (4-hydroxyphenyl)-1,3,5-triisopropylbenzene, trimellitic acid, 1,3,5-benzenetricarboxylic acid, pyromellitic acid, C ₆ H ₅ -Si-(O-Si(CH ₃ ) ₂ -C ₃ H ₆ -C ₆ H ₄ -OH) ₃ , CH ₃ -Si-(O-Si(CH ₃ ) ₂ -C ₃ H ₆ -C ₆ H ₄ -OH) _{3 ,} etc., wherein 1,1,1-parameter (4-Hydroxyphenyl)ethane, and 4-[4-[1,1-indolyl(4-hydroxyphenyl)ethyl]-α,α-dimethylbenzyl]phenol are most preferred.

The polyfunctional compound is preferably used in an amount of 0.1 to 0.95 mol%, more preferably 0.2 to 0.8 mol%, particularly preferably 0.3 to 0.6 mol%, more preferably the aromatic dihydroxy compound. When the amount of the polyfunctional compound used is 0.95 mol% or less, it is less likely to cause an increase in fish eyes, and when it is 0.1 mol% or more, the melt tension can be increased.

The transesterification method refers to a method in which the above compound is subjected to polycondensation in a transesterification reaction in a molten state while being heated in a presence or absence of a catalyst under a reduced pressure and/or an inert gas, the polymerization method, The device and the like are not limited. The apparatus to be used may, for example, be used: a stirred tank type reactor, a thin film reactor, a centrifugal thin film evaporation reactor, a surface renewal type biaxial mixing reactor, a biaxial horizontal stirring reactor, and a wet wall type. The reactor, a multi-well plate type reactor in which polymerization is carried out while being freely dropped, and a line-containing multi-well plate type reactor which is polymerized while being dropped along the line. In the present embodiment, a stepwise polycondensation reaction can be carried out in such a combination to obtain a desired polycarbonate. Preferably, for example, a low-molecular-weight molten prepolymer can be produced in a stirred tank type reactor, which is formed into a molten prepolymer, and then dropped in a perforated plate type reactor in which polymerization is allowed to proceed while freely falling. The polymerization was carried out in a line-containing multi-well plate type reactor in which polymerization was simultaneously carried out. In particular, the polymerizer provided after the melt mixer is preferred because it can reduce the loss after replacement when it is used in place of the line-contact down-flow type polymerizer having excellent efficiency. For such a manufacturing method, for example, U.S. Patent No. 5,589,564 and the like can be referred to. Further, the material of the reactor is not particularly limited, but at least the constituent material of the inner wall of the reactor is preferably selected from stainless steel, nickel, glass, and the like.

The temperature at which the melt polycondensation reaction is carried out in the transesterification reaction is preferably 50 to 320 °C. An aromatic monohydroxy compound is formed as the reaction progresses, so that the operation other than the reaction system can be increased to increase the reaction rate. Therefore, it is preferred to introduce an inert gas such as nitrogen, argon, helium, carbon dioxide, and a lower hydrocarbon gas which does not adversely affect the reaction, so that the generated aromatic monohydroxy compound is removed together with the gases. The method, the method of carrying out the reaction under reduced pressure, and the like. The preferred reaction pressure varies depending on the molecular weight of the product, preferably from 10 mmHg to normal pressure at the initial stage of polymerization, and preferably 20 mmHg or less at the late stage of polymerization, particularly preferably 10 mmHg or less, especially in the final polymerization vessel. 5mmHg or less is even better.

The steps (A), (B), and (C) of the present embodiment will be described below. Although the details are described in the first embodiment, the manufacturing method of the embodiment is not limited thereto.

The continuous production method of the branched carbonate of the present embodiment comprises: (A) a step of preparing a low molecular weight polycarbonate having a number average molecular weight of 1,000 to 10,000 by transesterification from an aromatic dihydroxy compound and a carbonic acid diester, and (B) a step of adding and mixing a polyfunctional compound in a liquid state to the low molecular weight polycarbonate, and (C) until the melt index (MI) of the low molecular weight polycarbonate is 10 g/10 min or less and the MIR is 14 or more. The step of carrying out the polymerization reaction.

The manufacturing system of the branched carbonate shown in Fig. 1 is composed of the following steps: a first agitation polymerization step including the agitation tank type first polymerization reactors 3A, 3B, and a second agitation tank type second polymerization device 3C a stirring polymerization step, a third agitation polymerization step including a stirred tank type third polymerization vessel 3D, a first line contact flow type polymerization step including a line contact flow type first polymerization unit 108A, and a second line contact flow type polymerization step The second line of the aggregator 108B contacts the down-flow polymerization step.

The step (A) includes the steps of 3A and 3B to 3C, 3D, and 108A.

The agitating tank type polymerizers 3A to 3D each include a polymerization raw material inlet 1A, 1B or a prepolymer inlet 1C, 1D, a vent 2A to 2D, an outlet 5A to 5D, and a stirrer 6A containing an anchor type stirring blade. 6D. In the stirring tank type first polymerization reactors 3A and 3B which are arranged in parallel, the aromatic dihydroxy compound and the diphenyl carbonate in the polymerization raw material are charged, and the first stirring polymerization step is carried out in batch form. The polymerization catalyst is generally added at this stage, but it may be added in a later step. The molten prepolymers 4A and 4B produced therein are supplied from the prepolymer inlet 1C through a transfer pipe in the agitating tank type second aggregator 3C. At this time, the transport of the molten prepolymers 4A and 4B can be carried out using the transport pump 8 provided in the middle of the transport line as needed. Further, the molten prepolymer 4C which is polymerized in the second agitation polymerization step is extruded by a transfer pump 7C provided on the outlet 5C of the agitating tank type second polymerization vessel 3C, and is transported in a stirring tank type third. The polymerizer 3D was supplied from the prepolymer inlet 1D. According to this operation, the second and third agitation polymerization steps can be continuously performed.

The molten prepolymer 4D produced in the third agitation polymerization step is further extruded from the transfer pump 7D from the outlet 5D of the agitation tank type third polymerization reactor 3D, and flows to the line to flow down the first polymerization device 108A via the transfer piping. transport.

Thereafter, the first and second lines are contacted with the flow-down polymerization step, and are continuously operated in the line contact flow type first and second polymerizers 108A, 108B. In the line contact flow type first and second polymerization reactors 108A, 108B, each of the prepolymer inlets 101A, 101B; the perforated plates 102A, 102B; the linear guides 103A, 103B; the gas supply ports 104A, 104B; Ports 105A, 105B; and outlets 107A, 107B.

The molten prepolymer 4D charged from the inlet 101A of the prepolymer is subjected to a polymerization reaction while flowing down while contacting the wire, and the molten prepolymer 109A is accumulated in the lower portion of the first polymerization device 108A of the linear contact flow type. Among them, the molten prepolymer 109A is preferably subjected to polymerization reaction until the number average molecular weight (Mn) is from 1,000 to 10,000. The number average molecular weight is preferably from 1,500 to 8,000, more preferably from 2,000 to 7,000. When Mn is 1000 or more, the loss at the time of replacement of the raw material can be reduced, and when it is 10,000 or less, the fish eye is reduced, and the hot water resistance tends to be lowered. The molten prepolymer 109A is extruded from the outlet 107A via the transfer pump 106A, and is transported to the prepolymer inlet 101B of the second polymerization type 108B of the line contact flow through the transfer piping. The number average molecular weight and the weight average molecular weight in the present embodiment can be measured by a gel chromatograph (GPC).

The step (B) is a step of adding and mixing a polyfunctional compound in a liquid state in the low molecular weight polycarbonate produced in the above step (A). This corresponds to the transfer pipe that is transported from the outlet 107A to the prepolymer inlet 101B in the first drawing, the melt mixer (pipe mixer) 110 that is installed in the middle of the transfer pipe, and the portion of the polyfunctional compound input pipe 111. Share. In this case, the polyfunctional compound is introduced into the melt mixer 110 via the polyfunctional compound introduction pipe 111 in a liquid state, and is mixed with the molten prepolymer 109A conveyed by the line contact flow type first polymerization device 108A. In the case where the depolymerization reaction occurs, it is operable to terminate in the melt mixer to reach equilibrium, and may be terminated in the subsequent transport piping. Further, since there is still a step (C), it is not necessary to react to the necessity of completely achieving the equilibrium of the depolymerization reaction in this step. Further, in order to make the mixing more uniform, a mixing zone such as a static mixer or the like may be provided in the transport pipe.

The operation of the step (B) may be carried out in the middle of the outlet 5D and the prepolymer inlet 101A in the system of Fig. 1, or in the middle of the piping of the outlet 5C and the prepolymer inlet 1D. In the step (B) of the present embodiment, a polyfunctional compound may be directly added to the transport pipe without using a melt mixer, and a mixed region may be provided in the transport pipe and the static mixer, and the reaction may be performed. The depolymerization reaction is also carried out during the polymerization. Among them, the melt mixer can use a mixing device such as a twin-screw extruder. In this case, the polyfunctional compound may be added in a molten state, and when it is a powder, it may be added in a state of being dissolved in a solvent. In order to reduce fish eyes and to improve hot water resistance, it is preferred that the polyfunctional compound is added in a molten state and dissolved in a solvent, and it is particularly preferably added in a state of being dissolved in a solvent.

In the present embodiment, the polyfunctional compound may be added to the melt mixer in a state of being dissolved in a solvent. a solvent for dissolving a polyfunctional compound, which is a mixture of a phenol, an aromatic dihydroxy compound, a carbonic acid diester, a ketone, an ether, an aromatic dihydroxy compound and a carbonic acid diester, a reactant, and a number average molecular weight of 5,000 or less. Compounds such as low molecular weight polycarbonates present in the factory are preferred. These solvents may be used singly or in combination of two or more. When such a compound is used as a solvent, the fisheye of the branched polycarbonate produced therefrom can be reduced. Although the reason is not clear, it is presumed that when these compounds are used as a solvent, the polyfunctional compound is more dispersed because the depolymerization reaction of the polycarbonate is caused. In this case, since the molecular weight of the polycarbonate is lowered by the depolymerization reaction, when the amount of reduction is too large, the production is not preferable, so it is preferable that the ratio of the molecular weight is lowered to less than 50%, more preferably less than 30%. The amount of solvent is determined by the method. Further, the solvent for dissolving the polyfunctional compound can also be added in a state of being dissolved in a solvent widely used such as methanol, ethanol, acetone or dichloromethane.

The "polyfunctional compound in a liquid state" in the present embodiment means a state in which the polyfunctional compound itself is in a molten state and a state in which a polyfunctional compound is dissolved in a solvent. Therefore, the polyfunctional compound forms a temperature in a liquid state, and any temperature can be selected in accordance with the solvent to be used.

The "polyfunctional compound in a liquid state" in the present embodiment means a state in which a polyfunctional compound reacts with a solvent and/or other components to be dissolved. Among them, other components may be catalysts that promote the reaction of the polyfunctional compound with the solvent. The catalyst may be selected according to the solvent, and a catalyst used in the polymerization reaction may also be used.

The step (C) is a step of carrying out a polymerization reaction of a low molecular weight polycarbonate to have a MI of polycarbonate of 10 g/min or less and a branching index MIR of 14 or more. This is equivalent to the portion of the second polymerizer 108B of the lower flow type in the first embodiment. The number of the aggregators in the step (C) is not particularly limited. When the number of the polymerizers is large, there is a concern that the replacement time in the raw material replacement becomes long and the loss is increased. Therefore, the polymerization reactor is preferably one.

The molten prepolymer 109A in the second polymerization device 108B of the lower flow type is in contact with the first polymerization device 108A of the linear contact flow type, and the polymerization reaction is carried out while flowing down the contact line, and the polymer 109B is melted. Accumulated in the lower portion of the first polymerization device 108B of the line contact flow. The molten polymer 109B is discharged from the outlet 107B via the discharge pump 106B, and is recovered as a branched polycarbonate.

The input line contacts the molten prepolymer 109A in the first polymerization reactor 108B in accordance with the temperature of the polymerization tank, and in the production of the higher molecular weight polymer, it is necessary to reduce the supply amount of the prepolymer to make it sufficient. Aggregation time. Therefore, the productivity of a polymer having a high molecular weight will be lowered. Further, when the supply of the prepolymer is small, there is a problem of quality problems other than productivity. When the supply is too slow, the retention of a portion of the prepolymer remaining on the wire will be the cause of the increase in fish eyes.

In the case of the previous method, there is a tendency to decrease productivity when MI < 5, and there is a concern that the fish eye increases in addition to the decrease in productivity when MI < 4.

In the method of the present embodiment, since a predetermined amount of the prepolymer is supplied to each of the wires, the productivity can be improved and the quality can be improved. In the case of the prior method, when the high molecular weight polymer is produced, the supply amount of the prepolymer to the line contact flow type second polymerization reactor 108B is limited. In contrast, in the method of the present embodiment, by putting the prepolymer to which the branching agent is added, it is possible to obtain an effect of enhancing the retention on the line when the line is flowed down.

Specifically, the supply amount of the prepolymer to the final polymerizer is in contact with the supply amount in the second polymerization device 108B, and the amount per unit time (hours) per kg line when using the line of 8 m (kg) More preferably, it is 0.3 to 3.0 kg / (hr ‧ ), more preferably 0.4 to 2.5 kg / (hr ‧ ), and more preferably 0.5 to 2.0 kg / (hr ‧ ) Among them, the supply amount of the prepolymer to the wire is proportional to the length of the wire.

When the supply amount is less than 0.3 kg / (hr ‧ ), the productivity is lowered, and at this time, some of the polymer is retained on the line to affect the product (increased fish eye, etc.). When the supply amount exceeds 3.0 kg/(hr ‧ ), the time during which the prepolymer having a residence time is in contact with the wire is shortened, so that it is difficult to form a sufficient molecular weight.

In the present embodiment, the reaction temperature in the steps (A) to (C) is preferably from 50 to 320 ° C, and from 100 to 300 ° C, from the viewpoint of having a sufficient MI and MIR, a hue, and a good number of fish eyes. Preferably, it is preferably from 130 to 280 ° C, especially from 150 to 270 ° C. Among them, the step (C) is preferably 250 to 320 ° C, more preferably 250 to 300 ° C, still more preferably 255 to 280 ° C, and even more preferably 260 to 270 ° C.

In the present embodiment, the range of ΔT (°C) defined by the following formula (I) is preferably -20 ° C to 20 ° C from the viewpoint of impact strength, hue, and gel formation of the branched polycarbonate obtained.

ΔT=T ₂ -T ₁ (I)

Wherein T ₁ represents the temperature (° C.) of the low molecular weight polycarbonate introduced into the final polymerization vessel in the step (C); T ₂ represents the temperature of the branched polycarbonate polymerized by the final polymerization reactor in the step (C) ( °C), T ₂ is 285 ° C or less.

T _{2 is} preferably from 250 to 285 ° C, more preferably from 260 to 275 ° C. In addition, the "final polymerizer" means a polymerization reactor in which the MI of the branched polycarbonate is 10 g/10 min or less.

In the general melt polymerization method, since the viscosity of the polymer increases as the molecular weight increases in the final polymerization vessel corresponding to the step (C) of the present embodiment, the temperature of the reactor must be greatly increased. The need to reduce the viscosity. In the method of the present embodiment, the final polymerizer uses an upright type polymerizer, whereby a branched polycarbonate having high viscosity and excellent physical properties and excellent quality which has not been obtained so far can be obtained.

In the present embodiment, MI can be measured in accordance with the method of ASTM D1238 at a temperature of 300 ° C and a load of 1.2 kg. The branch index MIR is similarly obtained by dividing the value measured by the load of 12 kg by the MI value. The branched polycarbonate produced in the step (C) of the present embodiment preferably has a MI of 10 g/10 min or less, more preferably 0.5 to 8 g/10 min, more preferably 1 to 6 g/10 min, particularly in use. In a large bottle such as a 5 gallon bottle, it is better at 2 to 4 g/10 min. When the ratio is smaller than this range, the formability tends to decrease, and when it is larger than 10 g/10 min, the formability tends to decrease. The branch index MIR is preferably in the range of 14 or more, more preferably 15 to 30, still more preferably 16 to 25. When the thickness is less than 14, the improvement in blow moldability is insufficient, so that molding defects and thickness deviation tend to occur, and when it is more than 30, there is a tendency for molding defects and thickness variations to increase fish eyes.

After the step (C), the produced branched polycarbonate is generally granulated, but it may be directly connected to a molding machine to form a molded article such as a sheet or a bottle. Further, in order to refine or remove the fish eye, a polymer filter having a filtration fineness of about 1 to 50 μm or the like may be further provided.

In another embodiment of the present embodiment, the step (A) may be followed by a step (D) of producing a polycarbonate by performing a polymerization reaction until the melt index is 100 g/10 min or less. In this manner, a plurality of polycarbonates can be produced. The following is a description of the aspect in which the step (D) is included, and is described with reference to FIG.

Fig. 2 is a schematic view showing a manufacturing system for manufacturing a plurality of polycarbonates. The manufacturing system is the same as the system shown in Fig. 1, and includes a first stirring polymerization step including agitating tank type first polymerization units 3A and 3B, and a second stirring polymerization step including a stirring tank type second polymerization unit 3C. And a third agitation polymerization step comprising a stirred tank type third polymerization vessel 3D, and a first line contact flow down polymerization step comprising a line contact flow type first polymerization vessel 108A, and a second polymerization reactor 108B containing a line contact flow type The second line contacts the downflow polymerization step. In addition to the above, the method for producing a plurality of types of polycarbonate according to the present embodiment further comprises: a third line contact flow type polymerization step comprising a line contact flow type third polymerization device 108C; a transfer pump 106A, 106D; and a branch portion 120.

The molten prepolymer 109A produced in the step (A) is discharged from the outlet 107A and then enters the delivery pipe. The transport piping includes branch portions 120 each forming a branch that communicates with the apparatus that performs the step (B) and the apparatus that performs the step (D). The molten prepolymer 109A flowing out of the outlet 107A flows toward the branch at the branch portion 120, at each downstream of its branch, and then by the transfer pump 106D and/or at the inlet of the step (B). The transfer pump 106A at the entrance of the step is extruded and transported to the prepolymer of the prepolymer inlet 101B of the line contact flow type second polymerization device 108B and/or the prepolymer of the line contact flow type third polymerization device 108C via the transfer piping. Entrance 101C.

When the transport pump 106D is operated, the branched polycarbonate is produced in the steps (A), (B), and (C) in the same manner as in the above embodiment. In the second diagram, the transport pump 106D is transported to the transport piping of 101B, the melt mixer (pipeline mixer) 110 provided in the middle of the transport piping, and the polyfunctional compound input piping 111, which are part of the step (B). Rather; the second aggregator 108B to the outlet 107B of the lower flow type is in contact with the portion of the step (C).

When the transport pump 106A is in operation, the first and third line contact flow down polymerization steps are continuously performed in the line contact flow down type first and third polymerizers 108A, 108C.

The step (D) is equivalent to the portion of the third type polymerizer 108C to the outlet 107C which is flow-contacted by the transport pump 106A. In the step (D), the molten prepolymer 109A which is transported by the transport 107A through the outlet 107A of the line first flow polymerization type first polymerization device 108A via the transport pipe is transported to the line contact flow type third aggregator 108C. The prepolymer is used for the inlet 101C.

The molten prepolymer 109A in the input line contact flow type third polymerization device 108C is the same as the line contact flow type first polymerization device 108A, and flows down while contacting the line while the molten polymer 109C is accumulated under the line contact flow. The lower portion of the first aggregator 108C. The molten polymer 109C is further discharged from the outlet 107C via the discharge pump 106C, and is recovered as a branched polycarbonate.

Further, the MI of the polycarbonate produced in the step (D) is 100 g/10 min or less, preferably 1 to 90 g/10 min, more preferably 5 to 80 g/10 min, which may be determined by the raw material of the production. When MI is in the above range, it can have excellent mechanical properties and formability.

The manufacturing system shown in Fig. 2 can be made into a branched polycarbonate comprising the step of introducing the polyfunctional compound into the melt mixer 110 (B) and in the subsequent step (C), and then in the step (D). Made of polycarbonate. At this time, the amount of the branched polycarbonate produced in the steps (B) and (C) and the polycarbonate produced in the step (D) can be adjusted by adjusting the operating conditions of the transport pumps 106A and 106D. At the same time, when either of the transport pumps 106A, 106D is stopped, the polycarbonate produced in the steps (B) and (C) or (D) can be produced in a single step. By operating in this embodiment, the loss of material replacement can be minimized. Further, in the second drawing, there are one (B) step, (C) step, and (D) step for each of the steps (A), but each of them may be plural.

In the present embodiment, in the viewpoints of obtaining sufficient MI and MIR, and having a good hue and a small number of fish eyes, the steps are (A), (B), (C), and (D). In any of the steps, the reaction temperature is preferably from 50 to 320 ° C, more preferably from 100 to 300 ° C, even more preferably from 130 to 280 ° C, particularly preferably from 150 to 270 ° C. Among them, the steps (C) and (D) are preferably in the range of 250 to 320 ° C, more preferably 250 to 300 ° C, particularly preferably 255 to 280 ° C, particularly preferably 260 to 270 ° C.

In the method of the present embodiment, when a branched polycarbonate composition containing a stabilizer such as a stabilizer, an antioxidant, a dye, a UV absorber, a flame retardant, or a reinforcing agent such as glass fiber or a filler is produced, Preferably, the branched polycarbonate is directly supplied to the extruder and the static type mixing agitator in a molten state in the final reactor of the steps (C) and (D), and then added, melted and mixed. Additives and the like are granulated.

In the method of the present embodiment, as the addition operation in the above step (A), a polymerization catalyst can be used. The polymerization catalyst to be used therein is not particularly limited as long as it is a user in the present category, and examples thereof include an alkali metal or an alkaline earth such as lithium hydroxide, sodium hydroxide, potassium hydroxide or calcium hydroxide. Metal hydroxides; alkali metal salts, alkaline earth metal salts, quaternary ammonium salts of hydrides of boron and aluminum such as lithium aluminum hydride, sodium borohydride, tetramethylammonium hydride, etc.; lithium hydride, sodium hydride, hydrogenation Alkali metal such as calcium or alkaline earth metal hydrogen compound; alkali metal or alkaline earth metal alkoxide such as lithium methoxide, sodium ethoxide or calcium methoxide; lithium benzene oxide, sodium phenoxide, magnesium phenate, LiO-Ar-OLi An alkali metal or an alkaline earth metal aryl oxide such as NaO-Ar-ONa (wherein Ar represents an aryl group); an alkali metal or an alkaline earth metal organic acid salt such as lithium acetate, calcium acetate or sodium benzoate; zinc oxide; Zinc compounds such as zinc acetate and zinc phenoxide; boron oxide, boric acid, sodium borate, trimethyl borate, tributyl borate, triphenyl borate, such as (R ¹ R ² R ³ R ⁴ )NB (R ¹ R ² R ³ R ⁴ ) represents ammonium borate, such as (R ¹ R ² R ³ R ⁴ )PB (R ¹ R ² R ³ R ⁴ ) The bismuth borate (wherein R ¹ , R ² , R ³ and R ^{4 are} each independently represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and a ring. a boron compound having 5 to 10 carbon atoms, a carbon ring aryl group having 5 to 10 carbon atoms, or a carbon ring aralkyl group having 6 to 10 carbon atoms; a bismuth compound such as sodium hydride, tetraalkyl hydrazine, tetraaryl fluorene or diphenyl-ethyl-ethoxy hydrazine; an antimony compound such as cerium oxide, cerium tetrachloride, cerium ethoxide or phenoxy hydrazine; a tin compound such as tin oxide, dialkyltin oxide, dialkyltin carboxylic acid, tin acetate or ethyltributoxytin bonded to an alkoxy group or an aryloxy group, or a tin compound such as an organotin compound Lead compounds such as lead oxide, lead acetate, lead carbonate, alkaline carbonate, lead and organic lead alkoxide or aryl oxide; quaternary ammonium salt, quaternary phosphonium salt, quaternary arsonium salt a compound such as a ruthenium compound such as ruthenium oxide or ruthenium acetate; a manganese compound such as manganese acetate, manganese carbonate or manganese borate; a titanium oxide, a titanium alkoxide or an aryl oxide; Compounds; zirconium acetate, zirconium oxide, zirconium alkoxide or aryl oxide, zirconium acetyl acetone and the like of the zirconium compound catalyst. When a catalyst is used, these catalysts may be used alone or in combination of two or more. Further, the amount of the catalyst used is preferably in the range of 10 ^-8 to 1 part by weight, more preferably 10 ^-7 to 10 ^-1 part by weight, based on 100 parts by weight of the raw material aromatic dihydroxy compound. .

The branched polycarbonate produced by the method of the present embodiment contains a main chain and a branch of a repeating unit represented by the following formula (1).

The branched polycarbonate produced by the method of the present embodiment may contain a branched structure (a) derived from a polyfunctional compound directly bonded to the main chain and the branched chain, and may contain the following formulas (2) and (3). And at least one branch structure (b) selected from the group consisting of the branch structures shown in (4).

The branched polycarbonate produced by the method of the present embodiment has a branched structure (a) and the following formulas (2), (3) and (4) with respect to the mass of the repeating unit represented by the above formula (1). The ratio of the total mass of the branched structure (b) shown is preferably from 0.2 to 1.0 mol%, more preferably from 0.3 to 0.9 mol%, even more preferably from 0.3 to 0.8 mol%. When it is more than 1.0 mol%, the increase in fisheye and the decrease in impact resistance or mechanical strength are caused. When it is less than 0.2 mol%, the effect of improving the formability tends to be reduced. The above-mentioned "mass" refers to the mass of the components derived from the respective structures which are produced when the branched polycarbonate is hydrolyzed.

(wherein Ar represents a divalent aromatic residue; Ar' represents a trivalent aromatic residue.)

The Ar system in the above formulae (1) and (3) is synonymous with Ar represented by HO-Ar-OH. Further, Ar' in the above formulas (2), (3), and (4) forms a bond with a substituent (for example, -COO-) which should be present at the branch starting point, and thus removes one hydrogen atom from Ar, and the like. Therefore, it represents a trivalent aromatic residue.

The branched polycarbonate produced by the method of the present embodiment preferably has a ratio of the mass of the branched structure (b) to the total mass of the branched structure (a) and the branched structure (b) of 0.1 to 0.6. More preferably from 0.2 to 0.6, and even more preferably from 0.3 to 0.6. When it is higher than 0.6, the hot water resistance tends to decrease; when it is less than 0.1, the MIR decreases and the increase in the melt tension tends to be small.

Further, with respect to the mass of the branched structure (b) represented by the above formulas (2) to (4), the ratio of the mass of the branched structure represented by the above formula (2) is preferably 0.5 or more, and is 0.85 or more. More preferably, it is better than 0.9. When it is less than 0.5, there is a tendency that impact resistance, mechanical strength is lowered, and fish eyes are increased.

The "main chain" in the present specification means a polymer chain formed by condensation of an aromatic dihydroxy compound as a raw material and a carbonic acid diester by transesterification. In this case, among the branched portions of the polyfunctional compound ("branched structure (a)"), among the branches existing in the plural, the longest branch in the branch is selected, and the branch is used as the primary bond.

The "branched structure (a)" in the present specification means a branched structure in which a branch is formed by a polyfunctional compound. For example, when 1,1,1-paraxan (4-hydroxyphenyl)ethane is used as the polyfunctional compound, the structure represented by the following formula becomes "branched structure (a)", and the branched structure (a) The mass of the material is the quantification of 1,1,1-paraxyl (4-hydroxyphenyl)ethane hydrolyzed.

In the present specification, the "branched structure (b)" refers to a branched structure which is formed naturally in the production process of a branched polycarbonate (for example, a Fries rearrangement reaction) with respect to a primary bond.

The branched polycarbonate produced in the present embodiment is preferably one which does not substantially contain a chlorine atom. According to the publication of International Publication No. 2005/121210, etc., in the present transesterification method, an aromatic dihydroxy compound substantially containing no chlorine atom, a diester carbonate, and a polyfunctional compound are used to form a branched polycarbonate. In the case where a chlorine-containing other compound is not added thereto, a branched polycarbonate having a chlorine atom content of 10 ppb or less, more preferably 1 ppb or less can be obtained.

In the branched polycarbonate produced in the present embodiment, when a film having a thickness of 50 μm and a width of 30 cm is formed, the number of fish eyes having a size of 300 μm or more is 100 or less, and 80 pieces are formed in an arbitrary length of 1 m. The following is better, preferably 50 or less.

The hue (b* value) of the branched polycarbonate produced in the present embodiment is preferably 0 to 3.0, more preferably 0 to 2.5, still more preferably 0 to 1.5. Above the above range, the branched polycarbonate seen will have a yellow color and thus its appearance is not good. Although it is possible to correct the yellow color contained in the coloring agent such as the blueing agent as needed, it is also necessary to consider the transparency.

The hue of the branched polycarbonate produced in the present embodiment can be measured and formed into a flat plate having a thickness of 3.2 mm at a cylinder temperature of 300 ° C and a mold temperature of 90 ° C, and then CR-made by Konica Minolta Co., Ltd., Japan. 400, placed on a white calibration plate and measured by a reflection method under the condition of measuring 8 mm in diameter, and then the difference between the b* value of the plate and the white calibration plate (b* value of the plate = measured value of the plate placed on the white calibration plate) - The measured value of the white calibration plate is calculated and found.

The branched structures (a) and (b) in the branched polycarbonate produced in the present embodiment can be completely hydrolyzed by the branched polycarbonate, and then quantified by reverse phase liquid chromatography. The hydrolysis of the polycarbonate can be carried out by a hydrolysis method at normal temperature as described in Polymer Degradation and Stability, 45 (1994): 127-137, which is easy to handle and does not cause side reactions during the decomposition, and can completely hydrolyze the branched polycondensation. Carbonate is preferred, and in the present embodiment, it can be carried out at room temperature (25 ° C).

In the continuous production method of the branched polycarbonate of the present embodiment, it may be further added according to the necessity thereof: a coloring agent, a heat stabilizer, an antioxidant, a weathering agent, an ultraviolet absorber, a mold release agent, and lubrication. Agent, antistatic agent, plasticizer, etc. Meanwhile, these additives or the like may be added to the polycarbonate resin in a molten state after the termination of the polymerization reaction, or may be added after the polycarbonate is first granulated, and then remelted and mixed.

Further, in the transesterification method, it is known that the branched structures (b) represented by the above formulas (2) to (4) are naturally formed. In the present embodiment, the branched structure may be formed again in the branched polycarbonate. In this case, the amount of the polyfunctional compound derived can be reduced by the amount of the branched structure (b). In this case, the total mass of the branched structure (a) derived from the polyfunctional compound and the branched structure (b) of the above formulas (2) to (4) naturally occurring in the transesterification method is relative to the formula (1) The mass of the repeating unit shown is preferably from 0.2 to 1.0 mol%, more preferably from 0.2 to 0.9 mol%, even more preferably from 0.3 to 0.8 mol%. When it is more than 1.0% by mole, the fish eye tends to increase. When it is less than 0.2% by mole, the MIR is lowered and the increase in the melt tension tends to be small.

When a representative bisphenol A of an aromatic dihydroxy compound is used, the above formulas (2) to (4) form the following formulas (9) to (11).

With such a branched structure, the branched polycarbonate can be completely hydrolyzed and then quantified by reverse phase liquid chromatography. The branched polycarbonate produced in the present embodiment has a ratio of the mass of the branched structure (b) to 0.1 to 0.6 with respect to the total mass of the branched structure (a) and the branched structure (b). Meanwhile, the ratio of the mass of the branched structure represented by the above formula (2) to the mass of the branched structure (b) is preferably 0.85 or more, more preferably 0.9 or more.

Example

Hereinafter, the present invention will be more specifically described by way of examples and comparative examples. However, the invention is not limited by the following examples.

Each of the evaluations was determined in the following manner.

(1) Molecular weight

(1-a) Number average molecular weight: using a gel chromatography instrument (HLC-8320GPC manufactured by Tosoh Corporation of Japan, using 2 TSK-GEL Super Multipore HZ-M, detected by RI detector) to eluent Tetrahydrofuran was measured at a temperature of 40 °C. The molecular weight was calculated from a calibration curve of standard monodisperse polystyrene (EasiVial manufactured by VARIAN Co., Ltd.) and a molecular weight calibration curve converted by the following formula.

M _PC =0.3591M _PS ^1.0388

(In the formula, the molecular weight of M _PC- based polycarbonate; the molecular weight of M _PS polystyrene.)

(1-b) Weight average molecular weight: using a gel chromatography instrument (HLC-8320GPC manufactured by Tosoh Corporation of Japan, using 2 TSK-GEL Super Multipore HZ-M, detected by RI detector) to eluent = tetrahydrofuran, liquid injection amount = 5 μl, measurement temperature = 40 ° C, detector = RI detector measurement. Adjustment of the test sample = 10 mg of the branched polycarbonate was dissolved in 10 ml of dichloromethane. The molecular weight was calculated from a calibration curve of standard monodisperse polystyrene (EasiVial (RED, YELLOW, GREEN), manufactured by Japan VARIAN Co., Ltd.) and a molecular weight calibration curve converted by the following formula.

M _PC =0.3591M _PS ^1.0388

(In the formula, the molecular weight of M _PC- based polycarbonate; the molecular weight of M _PS polystyrene.)

(2) MI, MIR: MI (melt index) was measured by the method of ASTM D1238 at a temperature of 300 ° C and a load of 1.2 kg. The MIR (branch index) was also obtained by dividing the value measured by the load of 12 kg by the MI value in the same manner.

(3) Hue: A plate having a cylinder temperature of 300 ° C and a mold temperature of 90 ° C was injection-molded into a plate of 15 cm × 15 cm × 3.2 mm in thickness, and then a CR-400 manufactured by Konica Minolta Co., Ltd., Japan, and a standard whiteboard. The difference in b* values (Δb*).

(4) Fisheye: Film forming machine (manufactured by Japan Tanabe Plastic Machinery Co., Ltd., 30mm Φ single-axis extruder, screw rotation speed 100rpm, discharge amount 10kg/hr, barrel temperature 280°C, T-die temperature 260°C, roller temperature 120 ° C) A film having a thickness of 50 μm and a width of 30 cm was formed, and the number of fish eyes having a size of 300 μm or more in any length of 1 m was visually calculated.

(5) Time until the end of the series change: After the preparation of the branched polycarbonate, the supply of the polyfunctional compound is stopped, and after the production of the polycarbonate having a MI of 10 g/10 min, the polymerization is measured every one hour. In the fisheye of carbonate, the time until the measured value becomes 1 or less is obtained.

(6) Amount of branching structure: After dissolving 55 mg of the polycarbonate in 2 ml of tetrahydrofuran, 0.5 ml of a solution of 5 equivalents of potassium hydroxide in methanol was added thereto, and stirred at 25 ° C for 2 hours to complete hydrolysis. Thereafter, 0.3 ml of concentrated hydrochloric acid was added thereto, followed by reverse phase liquid chromatography (LC-1100, manufactured by Agilent, USA). The reverse phase liquid chromatography was performed by Inertsil ODS-3 column (manufactured by GL Scientific Co., Ltd.), and the eluent was mixed with methanol and 0.1% phosphoric acid aqueous solution, and the column oven was 40 ° C. Measured by a gradient of 20/80 to 100/0 in a ratio of methanol/0.1% phosphoric acid aqueous solution, and quantified by a UV detector having a wavelength of 300 nm.

(7) Hot water resistance: The flat plate formed in the above (3) was immersed in hot water of 95 ° C for 300 hours, and then taken out, and placed in a constant temperature and humidity chamber maintained at 23 ° C and 50 RH %. After 24 hours, the occurrence of cracks was visually confirmed. A: no crack is generated, B: 1 to 9 cracks are generated, and C: 10 or more cracks are generated.

(8) Impact strength: A 5 gallon water bottle was formed using an injection molding machine ASB-650EXHS manufactured by Nippon Seiki ASB Co., Ltd. at a barrel temperature of 295 ° C, a mold center temperature of 60 ° C, a mold cavity of 30 ° C, and injection blow molding. It is about 25cm in diameter and about 50cm in height).

(8-a) Bottle strength: Fill the water bottle formed by the above operation with water, and drop the same bottle from the height of 1.5m from four directions of up, down, obliquely upward and obliquely downward, and then assess whether there is any rupture. (A: no cracking, C: cracking) (8-a) Shaby impact strength: Test pieces were prepared by injection molding in accordance with ISO 306 at a cylinder temperature of 300 ° C and a mold temperature of 90 ° C, and then tested by a notch.

<Example 1>

A branched polycarbonate was produced by the manufacturing system as shown in Fig. 1. The agitation tank type first polymerization devices 3A and 3B are provided with agitator 6A, 6B containing an anchor type stirring blade having an internal volume of 100 liters. The agitation tank type second aggregator 3C and the agitation tank type third aggregator 3D are provided with mixers 6C and 6D containing an anchor type stirring blade having an internal volume of 50 liters. The line contact flow type first and second polymerizers 108A and 108B include a perforated plate 102A having five holes, a perforated plate 102B having three holes, and linear guides 103A and 103B made of SUS316L having a diameter of 1 mm and a length of 8 m. The agitation tank type first polymerizers 3A and 3B can be alternately used, and the agitation tank type second aggregator 3C can be used continuously.

80 kg of a polymerization raw material obtained from bisphenol A as an aromatic dihydroxy compound and diphenyl carbonate as a carbonic acid diester (mole ratio of 1.06 to bisphenol A), and bisphenol A as a catalyst The sodium salt (75% by weight ppb based on the bisphenol A in the polymerization raw material) was added to the stirred tank type first polymerization vessel 3A from the polymerization raw material using the inlet 1A. The mixture was further stirred at a reaction temperature of 180 ° C, a reaction pressure of 1 atm, and a nitrogen flow rate of 1 liter / hr. After 4 hours, the outlet 5A was opened, and the molten prepolymer 4A was supplied to the stirring tank type second polymerization vessel 3C at a flow rate of 7 liters/hr.

Thereafter, the agitation tank type first polymerization vessel 3B is operated in the same manner as the agitation tank type first polymerization vessel 3A to obtain a molten prepolymer 4B. After the agitation tank type first polymerization vessel 3A is emptied, the outlet 5A of the agitation tank type first polymerization vessel 3A is closed, and the outlet 5B of the agitation tank type first polymerization vessel 3B is opened, and the molten prepolymer 4B is flowed at 7 liters. /hr is supplied from the agitation tank type first polymerization vessel 3B to the agitation tank type second polymerization vessel 3C. By repeating this operation, the molten prepolymers 4A and 4B can be continuously and continuously supplied to the stirring tank type second aggregator 3C.

Further, the molten prepolymer 4C was prepared by maintaining the stirring tank type second polymerization vessel 3C at a reaction temperature of 230 ° C and a reaction pressure of 13.0 kPa. Thereafter, after the capacity of the molten prepolymer 4C reaches 20 liters, a part of the molten prepolymer 4C is continuously taken out and supplied to the stirring tank type third polymerization reactor 3D while maintaining the content of 20 liters.

Further, the molten prepolymer 4D was prepared by maintaining the stirring tank type third polymerization vessel 3D at a reaction temperature of 265 ° C and a reaction pressure of 2.6 kPa. Thereafter, after the capacity of the molten prepolymer 4D reached 20 liters, a portion of the molten prepolymer 4D was taken out and continuously supplied to the line contact flow type first polymerization device 108A while maintaining the content of 20 liters in a fixed manner.

Further, the molten prepolymer 109A was prepared by maintaining the line contact flow type first polymerization device 108A at a reaction temperature of 265 ° C and a reaction pressure of 400 Pa. Thereafter, after the capacity of the molten prepolymer 109A reaches 10 liters, a portion of the molten prepolymer 109A is taken out by keeping the content of 10 liters in a fixed manner, and is continuously supplied to the line contact flow type second polymerization via the pipe mixer 110. 108B. The number average molecular weight of the molten prepolymer 109A was 7,500.

In a pipe mixer 110 maintained at a temperature of 265 ° C and a rotation speed of 15 rpm, a polyfunctional compound 1,1,1-gin(4-hydroxyphenyl)ethane and a solvent as a solvent are dissolved in a homogeneous solution (polyfunctional compound / The phenol ratio of phenol = 1/1.5 was mixed, and the molar ratio of the polyfunctional compound to the bisphenol A skeleton in the molten prepolymer 109A was 0.004, and was supplied from the pipe 111 at a temperature of 180 °C. The molten prepolymer, which was engraved before the addition of the second polymerization vessel 108B under the line contact flow, had a number average molecular weight of 4,000.

The branched polycarbonate was prepared by maintaining the wire contact flow type second polymerization device 108B at a reaction temperature of 265 ° C and a reaction pressure of 118 Pa. Then, after the capacity of the branched polycarbonate reaches 10 liters, the content of 10 liters is kept in a fixed manner, and the discharge pump 106B is continuously taken out from the outlet 107B in the form of a strand, and after being cooled, it is cut into pellets. Branched polycarbonate. The evaluation results of the produced branched polycarbonate are shown in Table 1. Further, in Tables 1 to 3, T ₁ represents the temperature (° C.) of the low molecular weight polycarbonate introduced into the final polymerization vessel; T ₂ represents the temperature (° C.) of the branched polycarbonate polymerized in the final polymerization vessel. ΔT is 0 °C.

<Example 2>

The solvent in Example 1 was changed to a solution in which acetone and phenol were uniformly dissolved (mixed in a weight ratio of polyfunctional compound / acetone / phenol = 1 / 2.5 / 0.1). The uniformly dissolved solution was supplied from a pipe 111 to a pipe mixer 110 at a temperature of 40 °C. Further, the wire was brought into contact with the flow-down type first polymerization vessel 108A, and maintained at a reaction temperature of 265 ° C and a reaction pressure of 790 Pa to prepare a molten prepolymer 109A. The molten prepolymer 109A had a number average molecular weight of 5,500. The molten prepolymer was engraved with a number average molecular weight of 4,200 before being fed into the second polymerization vessel 108B of the type below the line contact flow. Further, the flow rate of the molten prepolymer in the step (A) was adjusted so that the flow rate of the molten prepolymer per line in the final polymerization vessel was such that the values shown in Table 1 were obtained. Except for these changes, the same operation as in the first embodiment was carried out. The evaluation results of the produced branched polycarbonate are shown in Table 1. Its ΔT is 0 °C.

<Example 3>

The solvent in Example 2 was changed to a prepolymer having a number average molecular weight of 2,500. Wherein the weight ratio of the branching agent to the prepolymer is 1:2. The uniformly dissolved solution was supplied from the pipe 111 to the pipe mixer 110 at a temperature of 180 °C. The molten prepolymer 109A had a number average molecular weight of 5,700. The molten prepolymer of the former encapsulating second polymerizer 108B was added to the line contact flow, and its number average molecular weight was determined to be 4,900. Further, the flow rate of the molten prepolymer in the step (A) was adjusted so that the flow rate of the molten prepolymer of each line in the final polymerization vessel was such that the values shown in Table 1 were obtained. Except for these changes, the same operation as in the second embodiment was carried out. The evaluation results of the produced branched polycarbonate are shown in Table 1. Its ΔT is 0 °C.

<Example 4>

The solvent of Example 2 was changed to diphenyl carbonate (DPC) and bisphenol A (BPA). The uniformly dissolved solution was supplied from the pipe 111 to the pipe mixer 110 at a temperature of 180 °C. The mixing ratio of the branching agent to DPC and BPA is 1.5:0.5:1. Further, a disodium salt of bisphenol A (in terms of its sodium atom, 75 wt ppb based on bisphenol A in the polymerization raw material) was further added as a catalyst. The molten prepolymer 109A had a number average molecular weight of 5,700. The molten prepolymer of the former type of the second polymerizer 108B was added to the line contact flow, and the number average molecular weight thereof was determined to be 4,200. Further, the flow rate of the molten prepolymer in the step (A) was adjusted so that the flow rate of the molten prepolymer of each line in the final polymerization vessel was such that the values shown in Table 1 were obtained. Except for these changes, the same operation as in the second embodiment was carried out. The evaluation results of the produced branched polycarbonate are shown in Table 1. Its ΔT is 0 °C.

<Example 5>

The solvent in Example 2 was changed to DPC. The mixing ratio of the branching agent to the DPC was set to 1:0.67. The uniformly dissolved solution was supplied from the pipe 111 to the pipe mixer 110 at a temperature of 180 °C. The molten prepolymer 109A had a number average molecular weight of 5,700. The molten prepolymer of the former type of the second polymerization device 108B was added to the line contact flow, and the number average molecular weight thereof was determined to be 4,000. Further, the flow rate of the molten prepolymer in the (A) step was adjusted in such a manner that the flow rate of the molten prepolymer of each line in the final polymerization vessel was such that the values shown in Table 1 were obtained. Except for these changes, the same operation as in the second embodiment was carried out. The evaluation results of the produced branched polycarbonate are shown in Table 1. Its ΔT is 0 °C.

<Example 6>

As the solvent of the polyfunctional compound, acetone was used, and it was put into the stirring tank type third polymerization device 3D instead of being put into the pipe mixer 110. Further, the flow rate of the molten prepolymer in the step (A) was adjusted in such a manner that the flow rate of the molten prepolymer of each of the wires in the final polymerization reactor was such that the values shown in Table 1 were obtained. Except for these changes, the same operation as in the second embodiment was carried out. In this way, although there are some variations in the MI, it is possible to stably form branched polycarbonate. The evaluation results of the produced branched polycarbonate are shown in Table 1. Its ΔT is 0 °C.

<Example 7>

The polyfunctional compound in Example 2 was 4-[4-[1,1-indolyl(4-hydroxyphenyl)ethyl]-α,α-dimethylbenzyl]phenol, and the solvent was changed to acetone. The molten prepolymer 109A was prepared by maintaining the line contact flow type first polymerization device 108A at a reaction temperature of 265 ° C and a reaction pressure of 1000 Pa. Further, the flow rate of the molten prepolymer in the (A) step was adjusted in such a manner that the flow rate of the molten prepolymer of each line in the final polymerization vessel was such that the values shown in Table 1 were obtained. Except for these changes, the same operation as in the second embodiment was carried out. The evaluation results of the produced branched polycarbonate are shown in Table 2. Its ΔT is -0.2 °C.

<Example 8>

Dividing the ventilating pair at the end of the outlet 107B of the second polymerizer of the second type in contact with the solvent used in the phenol (mixed in a weight ratio of polyfunctional compound/phenol = 6/4) Shaft extruder (PCM30mm, L/D30, 265°C manufactured by Chiba Steel Co., Ltd.), and its polyfunctional compound 1,1,1-gin(4-hydroxyphenyl)ethane (relative to bisphenol A) The molar ratio of the skeleton was 0.004), which was supplied in the same manner as in Example 2 except that the vent port of the above-described twin-screw extruder was supplied in a powder form without being supplied through the pipe mixer 110. The evaluation results of the produced branched polycarbonate are shown in Table 2. Further, the flow rate of the molten prepolymer in the (A) step was adjusted in such a manner that the flow rate of the molten prepolymer of each line in the final polymerization vessel was such that the values shown in Table 1 were obtained. Its ΔT is 25 °C.

<Comparative Example 1>

A two-axis extruder equipped with a vent (a PCM 30 mm, L/D 30, and a temperature of 265 ° C manufactured by Chiba Steel Co., Ltd.) is provided at the end of the outlet 107B of the second polymerization device of the second type in contact with the line of Fig. 1 and has many The 1,1,1-paraxyl (4-hydroxyphenyl)ethane of the functional compound (the molar ratio to the bisphenol A skeleton is 0.004) is not supplied via the pipe mixer 110 and is ventilated by the above-described twin screw extruder. The operation was carried out in the same manner as in Example 2 except that the mouth was put into a powder form. The evaluation results of the produced branched polycarbonate are shown in Table 3. Further, the flow rate of the molten prepolymer in the step (A) was adjusted so that the flow rate of the molten prepolymer of each line in the final polymerization vessel was such that the values shown in Table 1 were obtained. Its ΔT is 0 °C.

<Comparative Example 2>

Except that the pipe mixer 110 in Fig. 1 is replaced with a ventilated single-shaft extruder, and the pipe of 107A is connected to the supply port of the single-shaft extruder, and the outlet of the single-axis extruder is connected to On the piping of 101B. Further, the polyfunctional compound 1,1,1-gin(4-hydroxyphenyl)ethane (molar ratio of 0.004 relative to the bisphenol A skeleton) was powdered from the vent of the above-mentioned uniaxial extruder. Other than the input, the other operations were carried out in the same manner as in the second embodiment. The evaluation results of the produced branched polycarbonate are shown in Table 3. Further, the flow rate of the molten prepolymer in the step (A) was adjusted so that the flow rate of the molten prepolymer of each line in the final polymerization vessel became the value shown in Table 1. Its ΔT is 0 °C.

<Comparative Example 3>

In addition to replacing the pipe mixer 110 of Fig. 1 with a vented twin-screw extruder (PCM30mm, L/D30, temperature 265 °C manufactured by Chiba Steel Co., Ltd.), and piping of 107A is connected to the twin-shaft extrusion. The supply port of the machine is connected to the outlet of the cross-type polymerization reactor (not shown). Further, the polyfunctional compound 1,1,1-gin(4-hydroxyphenyl)ethane (molar ratio of 0.004 relative to the bisphenol A skeleton) was put into the vent of the above-mentioned twin-screw extruder at room temperature. . It is connected to the final polymerizer of the twin-screw extruder, and instead of the polymerizer 108B, a horizontal-type aggregator is provided for the final polymerization reaction. The temperature of the horizontal polymerization reactor was set to 320 °C. Except for these changes, the same operation as in the second embodiment was carried out. The evaluation results of the produced branched polycarbonate are shown in Table 3. Its ΔT is 30 °C.

<Comparative Example 4>

In Fig. 1, the pipe mixer 110 is replaced with a ventilated twin-screw extruder (PCM30mm, L/D30, 265°C manufactured by Chiba Steel Co., Ltd.), and is connected to the twin-shaft extrusion by a pipe of 107A. The supply port of the machine is connected to the outlet of the cross-type polymerization reactor (not shown). And the polyfunctional compound 1,1,1-paran (4-hydroxyphenyl)ethane (mole ratio of 0.004 relative to the bisphenol A skeleton) and DPC, at room temperature by the above-mentioned twin-screw extruder The vent is put in. The weight ratio of branching agent to DPC was set to 1:0.6. And it is connected to the final polymerizer of the twin-screw extruder, and instead of the polymerizer 108B, a horizontal polymerization reactor is provided for the final polymerization reaction. The temperature of the horizontal polymerization reactor was set to 320 °C. Except for these changes, the same operation as in the second embodiment was carried out. The evaluation results of the produced branched polycarbonate are shown in Table 3. Its ΔT is 25 °C.

<Comparative Example 5>

In Example 2, no polyfunctional compound and a solvent were added. Among them, in order to produce a high molecular weight polymer of MI = 3, the supply amount to the final polymerization vessel 108B was minimized, and the supply amount per line was 0.2 kg/hr ‧ . Since it is necessary to extend the residence time in 103B to produce a polymer of MI = 3, it is made into a polymer having many fish eyes. Further, the productivity was rather inferior to that in the case of Example 2.

<Example 9>

Branched polycarbonate was produced using the manufacturing system shown in Fig. 2. Among them, the agitation tank type first polymerization devices 3A and 3B are provided with agitator 6A, 6B containing an anchor type stirring blade having an internal volume of 100 liters. The agitation tank type second aggregator 3C and the agitation tank type third aggregator 3D are provided with mixers 6C and 6D containing an anchor type stirring blade having an internal volume of 50 liters. The line contact flow type first and second polymerizers 108A and 108B include a perforated plate 102A having five holes, a perforated plate 102B having three holes, and linear guides 103A and 103B made of SUS316L having a diameter of 1 mm and a length of 8 m. The agitation tank type first polymerizers 3A and 3B can be alternately used, and the agitation tank type second aggregator 3C can be used continuously.

80 kg of a polymerization raw material prepared from bisphenol A as an aromatic dihydroxy compound and diphenyl carbonate as a carbonic acid diester (molar ratio of 1.07 to bisphenol A), and bisphenol A as a catalyst The sodium salt (in terms of its sodium atom, 50 parts by weight ppb relative to the bisphenol A in the polymerization raw material) was charged into the stirred tank type first polymerization vessel 3A. The reaction was further carried out at a reaction temperature of 185 ° C, a reaction pressure of 1 atm, and a nitrogen gas flow rate of 1 liter / hr. After 4 hours, the outlet 5A was opened, and the molten prepolymer 4A was supplied to the stirred tank type second aggregator at a flow rate of the flow rate of the molten prepolymer of each line in the final polymerization vessel to the value shown in Table 2. 3C.

Thereafter, the agitation tank type first polymerization vessel 3B is operated in the same manner as the agitation tank type first polymerization vessel 3A to prepare a molten prepolymer 4B. After the agitation tank type first polymerization vessel 3A is emptied, the outlet 5A of the agitation tank type first polymerization vessel 3A is closed, and the outlet 5B of the agitation tank type first polymerization vessel 3B is opened, and the prepolymer 4B is melted to finally polymerize. The flow rate of the molten prepolymer of each of the wires is a flow rate of the value shown in Table 2, and is supplied from the agitation tank type first polymerization device 3B to the agitation tank type second polymerization device 3C. By repeating this operation, the molten prepolymers 4A and 4B can be continuously and continuously supplied to the stirring tank type second aggregator 3C.

The molten prepolymer 4C was prepared by maintaining the stirring tank type second polymerization reactor 3C at a reaction temperature of 232 ° C and a reaction pressure of 12.8 kPa. Thereafter, after the capacity of the molten prepolymer 4C reaches 20 liters, a part of the molten prepolymer 4C is continuously taken out and supplied to the stirring tank type third polymerization reactor 3D while maintaining the content of 20 liters.

Further, the molten tank type third polymerization device 3D was maintained at a reaction temperature of 266 ° C and a reaction pressure of 2.5 kPa to obtain a molten prepolymer 4D. Thereafter, after the capacity of the molten prepolymer 4D reached 20 liters, a portion of the molten prepolymer 4D was taken out and continuously supplied to the line contact flow type first polymerization device 108A while maintaining the content of 20 liters in a fixed manner.

Further, the wire was brought into contact with the flow-down type first polymerization vessel 108A, and maintained at a reaction temperature of 266 ° C and a reaction pressure of 770 Pa to prepare a molten prepolymer 109A. Thereafter, after the capacity of the molten prepolymer 109A reached 10 liters, a part of the molten prepolymer 109A was taken out while maintaining the content of 10 liters in a fixed manner. The number average molecular weight of the molten prepolymer 109A was determined to be 5,000. The extracted molten prepolymer 109A is continuously supplied to the line contact flow type second polymerization device 108B via the pipe mixer 110 in a 1/2 amount thereof, and the other 1/2 amount is continuously supplied to the line contact flow type third. Aggregator 108C.

The polyfunctional compound 1,1,1-gin(4-hydroxyphenyl)ethane and the phenol as a solvent were uniformly dissolved in a weight ratio of 6:4 in a pipe mixer 110 maintained at a temperature of 266 ° C and a rotation speed of 15 rpm. The solution was supplied from a pipe 111 at a temperature of 185 ° C with respect to the bisphenol A skeleton in the molten prepolymer 109A in a molar ratio of 0.003. The amount of the pre-molten molten prepolymer of the second polymerizer 108B under the line contact flow was measured to have a number average molecular weight of 4,400.

Further, the wire was brought into contact with the second polymerization reactor 108B, and maintained at a reaction temperature of 266 ° C and a reaction pressure of 122 Pa to prepare a branched polycarbonate. Then, after the capacity of the branched polycarbonate reaches 10 liters, the content of the branched polycarbonate is maintained at 10 liters, and the discharge pump 106B is continuously taken out from the outlet 107B in the form of a strand, and then cooled and cut to obtain a granular shape. Branched polycarbonate. The evaluation results of the produced branched polycarbonate are shown in Table 3.

Further, the wire was brought into contact with the flow-down third polymerization device 108C to maintain a reaction temperature of 266 ° C and a reaction pressure of 135 Pa to obtain a polycarbonate. Then, after the capacity of the polycarbonate reaches 10 liters, the amount of the content is kept to 10 liters, and the discharge pump 106C is continuously taken out from the outlet 107C in the form of a strand, and after being cooled and cut, the MI is made 10 g/ A linear polycarbonate having a particle size of 0.6 and a fishy eye with a measured value of 0. After 50 hours of continuous operation, the flow ratio of 106A to 106D is 50:50, and the production ratio of branched polycarbonate to linear polycarbonate is changed to control the production amount without loss during the replacement of raw materials. Production of polycarbonate. The evaluation results of the produced branched polycarbonate are shown in Table 2.

Industrial use possibility

In the production method of the present invention, when the branched polycarbonate is produced by the transesterification method, the loss at the time of replacement of the raw material can be reduced, and the hue and hot water resistance are excellent, and the fish eyes are small, so that the MIR can be provided, the extrusion use and the blowing can be provided. Branched polycarbonate excellent in gas formability.

1A, 1B. . . Polymer raw material inlet

1C, 1D. . . Prepolymer inlet

2A, 2B, 2C, 2D, 105A, 105B, 105C. . . Vent

3A, 3B. . . Stirred tank type first aggregator

3C. . . Stirred tank type second aggregator

3D. . . Stirred tank type third aggregator

4A, 4B, 4C, 4D, 109A. . . Melted prepolymer

5A, 5B, 5C, 5D, 107A, 107B, 107C. . . Export

6A, 6B, 6C, 6D. . . Mixer

7C, 7D, 8, 106A. . . Transport pump

101A, 101B, 101C. . . Prepolymer inlet

102A, 102B, 102C. . . Multiwell plate

103A, 103B, 103C. . . Linear guide

104A, 104B, 104C. . . Gas supply埠

106B, 106C. . . Drain pump

108A. . . Line contact flow type first aggregator

108B. . . Line contact flow type second aggregator

108C. . . Line contact flow type third aggregator

109B, 109C. . . Molten polymer

110. . . Melt mixer (pipe mixer)

111. . . Polyfunctional compound input piping

120. . . Branch

Fig. 1 is a schematic view showing a manufacturing system for producing a branched polycarbonate according to an embodiment of the present invention.

Fig. 2 is a schematic view showing a manufacturing system for producing a plurality of types of polycarbonates according to an embodiment of the present invention.

1A, 1B. . . Polymer raw material inlet

1C, 1D. . . Prepolymer inlet

2A, 2B, 2C, 2D, 105A, 105B. . . Vent

3A, 3B. . . Stirred tank type first aggregator

3C. . . Stirred tank type second aggregator

3D. . . Stirred tank type third aggregator

4A, 4B, 4C, 4D, 109A. . . Melted prepolymer

5A, 5B, 5C, 5D, 107A, 107B. . . Export

6A, 6B, 6C, 6D. . . Mixer

7C, 7D, 8, 106A. . . Transport pump

101A, 101B. . . Prepolymer inlet

102A, 102B. . . Multiwell plate

103A, 103B. . . Linear guide

104A, 104B. . . Gas supply埠

106B. . . Drain pump

108A. . . Line contact flow type first aggregator

108B. . . Line contact flow type second aggregator

109B. . . Molten polymer

110. . . Melt mixer (pipe mixer)

111. . . Polyfunctional compound input piping

Claims (8)

A method for continuously producing a branched polycarbonate comprising the following steps (A) to (C): (A) a transesterification method from an aromatic dihydroxy compound and a carbonic acid diester to form a number average molecular weight of 1,000 to 10,000 a step of low molecular weight polycarbonate, and (B) a step of adding and mixing a polyfunctional compound in a liquid state in the aforementioned low molecular weight polycarbonate, and (C) continuing until the melt index of the low molecular weight polycarbonate is 10 g The polymerization reaction is carried out until /10 min or less and the branch index is 14 or more to prepare a branched polycarbonate. The method according to claim 1, wherein the ΔT (°C) defined by the following formula (I) ranges from -20 ° C to 20 ° C, and ΔT = T _{2 -} T ₁ (I) , T ₁ represents the temperature (° C.) of the low molecular weight polycarbonate introduced into the final polymerization vessel in the above step (C); T ₂ represents the temperature of the branched polycarbonate polymerized by the aforementioned final polymerization reactor in the above (C) step (° C. ), T ₂ is 285 ° C or less]. The method according to claim 1 or 2, wherein the polyfunctional compound is added to the apparatus for performing the above step (A) and the apparatus for performing the above (C) in a state of being dissolved in a solvent. The piping is in the middle of the melt mixer. The method of claim 3, wherein the solvent is a mixture of a phenol, a carbonic acid diester, a ketone, an ether, an aromatic dihydroxy compound and a carbonic acid diester, and a reactant, and an average amount. At least one selected from the group consisting of low molecular weight polycarbonates having a molecular weight of 5,000 or less. The method according to any one of claims 1 to 4, wherein the solvent is a depolymerization solvent. The method according to any one of claims 1 to 5, wherein the step (A) is continued, and (D) is further carried out until the melt index becomes 100 g/10 min or less to carry out a polymerization reaction to produce a polycarbonate. step. The method of claim 6, wherein the apparatus for performing the step (A) is branched by means of a device having the steps (C) and the step (D) The piping of the branching portion is connected to the apparatus for performing the above step (C) and the apparatus for performing the above step (D), and the polyfunctional compound is added between the branching portion and the device for performing the above step (C). The piping is in the middle of the melt mixer. A branched polycarbonate produced by the method of any one of claims 1 to 7.