KR100676301B1 - Method for preparing polycarbonate-co-siloxane - Google Patents

Abstract

The present invention relates to a method for preparing a high molecular weight siloxane copolycarbonate resin, and more particularly, to a polymerization degree obtained by a transesterification reaction by introducing a condensation polymerization step in the preparation of a high molecular weight siloxane copolycarbonate resin. By lowering the mole fraction of allyl carbonate present in the end groups of the reaction by-products below and unreacted diaryl carbonate, the molecular weight increase of the siloxane copolycarbonate after solid phase polymerization can be maximized. It can significantly shorten the time required to manufacture, there is no risk because phosgene is not used as a toxic substance, there is an effect that can prevent the degradation of quality.

Siloxane copolycarbonate, transesterification, condensation polymerization, crystallization, solid phase polymerization

Description

Method for preparing siloxane copolycarbonate {Method for preparing poly (carbonate-co-siloxane)}

The present invention lowers the mole fraction of the end groups of the reaction by-products obtained as a result of the transesterification reaction and the unreacted diaryl carbonate in the unreacted diaryl carbonate by introducing a condensation polymerization step, thereby increasing the molecular weight of the siloxane copolycarbonate after solid phase polymerization. Not only to maximize, but also to a method for producing a siloxane copolycarbonate resin that can significantly shorten the time required to prepare a siloxane copolycarbonate of the same molecular weight.

Polycarbonate resins are very excellent in heat resistance, impact resistance, mechanical strength, transparency, and the like, and are widely used in the manufacture of compact discs, transparent sheets, packaging materials, automobile bumpers, and sunscreen films, and the demand is rapidly increasing.

However, when exposed to a conventional polycarbonate solvent, there is a problem in that the solvent resistance is poor, such as exhibiting a crazing or cracking phenomenon, and low impact strength at low temperatures. Therefore, various modified polycarbonates have been tried to improve these problems, among which siloxane-based copolycarbonates exhibit particularly excellent properties in terms of low temperature impact strength, formability, and flowability.

In the production of such siloxane copolycarbonates, conventional production processes can be classified into an interfacial polymerization step using phosgene, a melt polymerization step without phosgene, and a solid phase polymerization step. The interfacial polymerization process involves reacting an aromatic hydroxy compound with a dihydroxy compound, a phosgene and a catalyst with a hydroxyaryl terminated diorganopolysiloxane, as described in US Pat. No. 5,530,083. The above method can produce a high molecular weight siloxane copolycarbonate resin relatively easily in a continuous process, but there is a problem in that the use of toxic poison gas and chlorine-based organic solvents, which are pollutants, is very dangerous and thus requires huge equipment costs. .

On the other hand, the melt polymerization process is a method of proceeding the polymerization in the state of melting the starting material, as disclosed in US Patent No. 6,252,013, there is an advantage that there is little risk of using no toxic substances, but a high amount of extrusion siloxane system In order to produce copolycarbonates, high-temperature, high-vacuum equipment is required when treating high-viscosity reactants, and thus there is a problem in that quality is reduced.

On the other hand, the solid phase polymerization process is a method of crystallizing a low molecular weight siloxane-based copolycarbonate prepolymer and then proceeding the polymerization reaction at a temperature lower than the melting temperature. Although it is possible to prevent the deterioration, generally known solid phase polymerization process is a process for removing reaction by-products of less than 3 degree of polymerization and unreacted diaryl carbonate present with relatively low molecular weight (weight average molecular weight: 2,000 to 20,000 g / mol) prepolymer. There is a problem in that a high molecular weight siloxane copolycarbonate cannot be obtained within a short time due to the large molar ratio between the aromatic group and the aryl carbonate period by going through the crystallization process and the solid state polymerization process.

Therefore, there is no risk, it is possible to prevent the deterioration of quality, and further studies on a manufacturing method capable of economically manufacturing high molecular weight siloxane-based copolycarbonates in a short time are needed.

In order to solve the above problems, the first technical problem is to reduce the reaction time of the solid phase polymerization reaction step by introducing a reduced pressure condensation reaction step, there is no risk of using a phosgene as a toxic substance, to prevent quality degradation It is to provide a method for producing a siloxane copolycarbonate having an effect that can be.

The second technical problem of the present invention is to provide a siloxane-based copolycarbonate prepared by the above method.

In order to achieve the first task,

The present invention provides a) a low molecular weight amorphous siloxane-based copolycarbonate prepolymer having a weight average molecular weight of 1,500 to 20,000 g / mol by melting and transesterifying a diaryl carbonate, an aromatic dihydroxy compound, and a polysiloxane under a catalyst. Doing;

b) condensation polymerization of the low molecular weight amorphous siloxane copolycarbonate prepolymer of step a) to prepare a medium molecular weight amorphous siloxane copolycarbonate having a weight average molecular weight of 10,000 to 30,000 g / mol;

c) preparing a crystalline siloxane copolycarbonate from the medium molecular weight amorphous siloxane copolycarbonate of step b); And

d) solid-phase polymerization of the crystalline siloxane copolycarbonate of step c) to prepare a high molecular weight siloxane copolycarbonate having a weight average molecular weight of 20,000 to 200,000 g / mol. It provides a method for producing a polycarbonate resin.

In order to achieve the second task,

The present invention provides a siloxane copolycarbonate prepared by the above method.

Hereinafter, the present invention will be described in detail.

The inventors of the present invention have been studying a method for greatly improving the molecular weight of siloxane copolycarbonate within a short time, and the degree of polymerization obtained by the transesterification reaction by introducing a reaction step of condensation polymerization at a constant reaction temperature under reduced pressure or nitrogen injection. By lowering the mole fraction of the aryl carbonates present in the end groups of the reaction by-products and the unreacted diaryl carbonates, the molecular weight increase of the siloxane copolycarbonates after solid phase polymerization can be maximized, and siloxane copolycarbonates having the same molecular weight The present invention has been completed by finding that the time required for manufacture can be significantly reduced.

First step: transesterification step

As the aromatic dihydroxy compound which is one of the starting raw materials used in the transesterification reaction of the present invention, a compound represented by the following Chemical Formula 1 may be used:

[Formula 1]

In Chemical Formula 1,

R ¹ and R ² are each independently a halogen atom or an alkyl group having 1 to 8 carbon atoms; Each independently halogen atom such as fluorine, chlorine, bromine or iodine or methyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, secondary-butyl group, tert-butyl group, pentyl group, An alkyl group having 1 to 8 carbon atoms, such as a hexyl group, a cyclohexyl group, a heptyl group, or an octyl group,

Z is a single bond or an alkylene group having 1 to 8 carbon atoms, an alkylidene group having 2 to 8 carbon atoms, a cycloalkylene group having 5 to 15 carbon atoms, a cycloalkylidene group having 5 to 15 carbon atoms, -S, -SO-,- SO _2- , -O-, -CO-, a compound represented by the following formula (2) or a compound represented by the following formula (3). At this time, the alkylene group having 1 to 8 carbon atoms or the alkylidene group having 2 to 8 carbon atoms include methylene group, ethylene group, propylene group, butylene group, pentylene group, hexylene group, ethylidine group, isopropylidene group, and the like. , A cycloalkylene group having 5 to 15 carbon atoms or a cycloalkylidene group having 5 to 15 carbon atoms includes a cyclopentyl group, a cyclohexylene group, a cyclopentylidene group, a cyclohexylidene group, and the like:

a and b are each independently an integer of 0 to 4;

 [Formula 2]

[Formula 3]

Examples of the aromatic dihydroxy compound represented by Chemical Formula 1 include bis (4-hydroxyphenyl) methane, bis (3-methyl-4-hydroxyphenyl) methane and bis (3-chloro-4-hydroxyphenyl) methane , Bis (3,5-dibromo-4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, 1,1-bis (2-tert-butyl-4-hydroxy -3-methylphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane (bisphenol A), 2,2-bis (3-methyl-4-hydroxyphenyl) propane, 2,2-bis (2 -Methyl-4-hydroxyphenyl) propane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane, 1,1-bis (2-tert-butyl-4-hydroxy-5 -Methylphenyl) propane, 2,2-bis (3-chloro-4-hydroxyphenyl) propane, 2,2-bis (3-fluoro-4-hydroxyphenyl) propane, 2,2-bis (3- Bromo-4-hydroxyphenyl) propane, 2,2-bis (3,5-difluoro-4-hydroxyphenyl) propane, 2,2-bis (3,5-dichloro-4-hydroxyphenyl Propane, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) prop Ropan, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, 2,2-bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxy-1-methylphenyl) propane, 1,1-bis (4-hydroxy-tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3-bromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (4-hydroxy -3-chlorophenyl) propane, 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, 2,2-bis (3-bromo-4-hydroxy-5-chlorophenyl) propane, 2,2-bis (3-phenyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (3-methyl-4-hydroxyphenyl) butane, 1,1-bis (2-butyl-4-hydroxy-5-methylphenyl) butane, 1,1-bis (2-tert-butyl-4-hydroxy-5-methylphenyl) butane, 1,1-bis (tertiary 2-3) -part 4-hydroxy-5-methylphenyl) isobutane, 1,1-bis (2-tert-amyl-4-hydroxy-5-methylphenyl) butane, 2,2-bis (3,5-dichloro-4 -Hydroxyphenyl) butane, 2,2-bis (3,5-dibromo-4-hydrophenyl) butane, 4,4-bis (4-hydroxyphenyl) heptane, 1,1-bis (2- Bis (hydroxyaryl) such as tert-butyl-4-hydroxy-5-methylphenyl) heptane, 2,2-bis (4-hydroxyphenyl) octane, or 1,1- (4-hydroxyphenyl) ethane Alkane; 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (3-methyl-4-hydroxyphenyl) cyclohexane, 1 , 1-bis (3-cyclohexyl-4-hydroxyphenyl) cyclohexane, 1,1-bis (3-phenyl-4-hydroxyphenyl) cyclohexane, or 1,1-bis (4-hydroxyphenyl Bis (hydroxyaryl) cycloalkanes such as) -3,5,5-trimethylcyclohexane; Bis (hydroxyaryl) ethers such as bis (4-hydroxyphenyl) ether or bis (4-hydroxy-3-methylphenyl) ether; Bis (hydroxyaryl) sulfides such as bis (4-hydroxyphenyl) sulfide or bis (3-methyl-4-hydroxyphenyl) sulfide; Bis (hydroxyaryl) sulfoxides such as bis (hydroxyphenyl) sulfoxide, bis (3-methyl-4-hydroxyphenyl) sulfoxide, or bis (3-phenyl-4-hydroxyphenyl) sulfoxide; Bis (hydroxyaryl) sulfones such as bis (4-hydroxyphenyl) sulfone, bis (3-methyl-4-hydroxyphenyl) sulfone, or bis (3-phenyl-4-hydroxyphenyl) sulfone; Or 4,4'-dihydroxyphenyl, 4,4'-dihydroxy-2,2'-dimethylbiphenyl, 4,4'-dihydroxy-3,3'-dimethylbiphenyl, 4,4 Dihydroxybiphenyl, such as' -dihydroxy-3,3'- dicyclohexyl biphenyl or 3, 3- difluoro-4,4'- dihydroxy biphenyl, can be used.

Aromatic dihydroxy compounds usable in addition to the compound represented by Formula 1 include dihydroxybenzene, halogen, or alkyl-substituted dihydroxybenzene, and examples thereof include resorcinol and 3-methylresorci Knoll, 3-Ethyl Resorcinol, 3-Proplysorcinol, 3-butyl Resorcinol, 3-tert-butyl Resorcinol, 3-Phenyl Resorcinol, 3-Cumolesor Sinol, 2,3,4,6-tetrafluororesorcinol, 2,3,4,6-tetrabromoresorcinol, catechol, hydroquinone, 3-methylhydroquinone, 3-ethylhydro Quinone, 3-propylhydroquinone, 3-butylhydroquinone, tert-butylhydroquinone, 3-phenylhydroquinone, 3-cumylhydroquinone, 2,5-dichlorohydroquinone, 2,3,5,6 Tetramethylhydroquinone, 2,3,5,6-tetra-tert-butylhydroquinone, 2,3,5,6-tetrafluorohydroquinone, or 2,3,5,6-tetrabromohydro Quinones and the like.

Bisphenol A is most preferred as an aromatic dihydroxy compound which is a starting material used in the transesterification reaction of the present invention.                     

As the diaryl carbonate, which is one of the starting raw materials used in the transesterification reaction, a compound represented by the following Chemical Formula 4 or a compound represented by the following Chemical Formula 5 may be used:

[Formula 4]

In Chemical Formula 4,

Ar ¹ and Ar ² are each independently an aryl group,

[Formula 5]

In Chemical Formula 5,

Ar ³ and Ar ⁴ are each independently an aryl group,

D ¹ is a residue obtained by removing two hydroxyl groups from the aromatic dihydroxy compound represented by the formula (1).

Examples of the diaryl carbonate represented by Formula 4 or Formula 5 include diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, bis (m-cresyl) carbonate, dinaphthyl carbonate, and bis (diphenyl) Carbonates or bisphenol A-bisphenol carbonates.

Diphenyl carbonate is most preferred as the diallyl carbonate, which is the starting raw material used in the transesterification reaction of the present invention.

As the polysiloxane compound which is one of the starting raw materials used in the transesterification reaction, a compound represented by the following Chemical Formula 6 may be used.

[Formula 6]

In Chemical Formula 6,

n is an integer of 1 to 500, R ³ , R ^{3 '} , R ⁴ and R ^4' are each independently a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and some or all of the hydrogen atoms of the alkyl group are independently Can be substituted with halogen atoms,

R ⁵ and R ⁶ are each independently a linear or branched alkylene group having 1 to 20 carbon atoms, a monocyclic or polycyclic arylene group having 6 to 30 carbon atoms, or -R ⁷ -XR ^8- ; R ⁷ and R ⁸ are each independently a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, X is -O-, -S-, -SO-, -SO _2- , or -CO-.

Examples of the polysiloxane compound represented by Chemical Formula 6 include polydialkylsiloxane-bisalkyloxyalcohols and the like.

The polysiloxane compound which is the starting raw material used in the transesterification reaction of the present invention is most preferably a compound represented by the following Chemical Formula 7.

[Formula 7]

In Formula 7, x is an integer of 1 to 500.

The diaryl carbonate is preferably included in 1.0 to 1.5 moles with respect to 1 mole of the dihydroxy compound. More preferably, it is 1.0-1.3 mol, Most preferably, it is 1.0-1.2 mol. When the content is less than 1.0 mole or larger than 1.5 mole, the degree of polymerization is low by the following formula, which is not preferable.

[Equation 1]

Wherein r is the molar ratio of hydroxy compound groups to carbonate groups, X _n is the degree of polymerization and p is the extent of reaction. In this case, when the reaction degree p has a value of 1.0, Equation 1 can be represented by the following Equation 2, and by adjusting r to a value close to 1.0, the polymerization degree can be maximized within a short time.

 [Equation 2]

Preferably, the polysiloxane compound contains 0.01 to 20 mol% of siloxane repeating units in 1 mol of the dihydroxy compound. More preferably, it is 0.1-15 mol%, Most preferably, it is 0.5-5 mol%. If the content is less than 0.01 mol%, it is impossible to secure differentiated properties from polycarbonate. If the content is greater than 20 mol%, gelation occurs due to the increase in the concentration of polysiloxane locally, which adversely affects the reaction.

As the polymerization catalyst used in the present invention, the metal compound catalyst system and the non-metal compound catalyst system may be used independently, or may be used in combination. As a metal compound catalyst system, an organic metal compound containing a salt compound such as hydroxide, acetate, alkoxide, carbonate, hydride, hydroxide, or oxide of an alkali or alkaline earth metal and a transition metal such as zinc, cadmium, titanium, or lead And aluminum hydride or borohydride may be used.

In addition, as the non-metal compound catalyst system, tetramethyl ammonium hydroxide, tetramethyl ammonium acetate, tetramethyl ammonium formate, tetramethyl ammonium carbonate, tetraethyl ammonium hydroxide, tetrapropyl ammonium hydroxide, tetrabutyl ammonium hydroxide Quaternary ammonium salts such as tetraphenyl ammonium hydroxide and trimethylphenyl ammonium hydroxide; Tetramethyl phosphonium hydroxide, tetramethyl phosphonium acetate, tetramethyl phosphonium formate, tetramethylphosphonium carbonate, tetraethyl phosphonium hydroxide, tetrapropyl phosphonium hydroxide, tetrabutyl phosphonium hydroxide Quaternary phosphonium salts such as tetraphenyl phosphonium hydroxide and trimethylphenyl phosphonium hydroxide; Primary, secondary or tertiary amine compounds; Or aromatic compound derivatives containing nitrogen such as pyridine.

The non-metal compound catalyst system is preferably included in 10 ^-1 to 10 ^-6 mol for 1 mol of the dihydroxy compound used as a starting raw material of the transesterification reaction of the present invention, more preferably from ^10-2 to ^{10- It is} included in ⁵ moles, most preferably from 10 ^-3 to 10 ^-4 moles. If the content is less than 10 ^-6 moles, the catalyst activity can not be sufficiently exhibited at the beginning of the reaction, if the content is larger than 10 ^-1 moles there is a problem that the cost increases and is uneconomic.

The compound containing the alkali metal or alkaline earth metal used in the present invention is not particularly limited, but preferably hydroxides such as lithium, sodium, potassium, rubidium, cesium, beryllium, magnesium, calcium, strontium, barium, Preference is given to using carbonate, acetate, alkoxide, or borohydride compounds.

The compound containing the alkali metal or alkaline earth metal is preferably contained in a molar amount of 10 ^-3 to 10 ^-8 moles with respect to 1 mole of the dihydroxy compound used as a starting raw material of the transesterification reaction of the present invention, more preferably 10 ^-4 to 10 ^-7 mol, and most preferably 10 ^-5 to 10 ^-6 mol. If the content is less than 10 ^-8 moles, the catalytic activity can not be sufficiently exhibited in the later stage of the reaction, if the content is greater than 10 ^-3 moles, the cost is increased, and the heat resistance and hydrolysis resistance of the final siloxane copolycarbonate resin There is a problem that can damage the physical properties of the back.

In the production of the polycarbonate resin through the transesterification reaction of the present invention, additives such as terminal stoppers and antioxidants may be further used as necessary.

The terminating agent is on-butylphenol, mn-butylphenol, pn-butylphenol, o-isobutylphenol, m-isobutylphenol, p-isobutylphenol, o-tert-butylphenol, m-tertiary Butylphenol, p-tert-butylphenol, on-pentylphenol, mn-pentylphenol, pn-pentylphenol, on-hexylphenol, mn-hexylphenol, pn-hexylphenol, o-cyclohexylphenol, m- Cyclohexylphenol, p-cyclohexylphenol, o-phenylphenol, m-phenylphenol, p-phenylphenol on-nonylphenol, mn-nonylphenol, pn-nonylphenol, o-cumylphenol, m-cumylphenol, p Cumylphenol, o-naphthylphenol, m-naphthylphenol, p-naphthylphenol, 2,6-di-tert-butylphenol, 2,5-di-tert-butylphenol, 2,4- Di-tert-butylphenol, 3,5-di-tert-butylphenol, 3,5-di-cumylphenol, 3,5-dicumylphenol, a compound represented by the following formula (8), represented by the following formula (9) Compound, a compound represented by Formula 10, a compound represented by Formula 11, a compound represented by Formula 12, Group formula 13 compound, or can be used to be displayed as a monovalent phenol derivatives, such as only chroman of the formula 14 or formula 15:

[Formula 8]

[Formula 9]

[Formula 10]

[Formula 11]

In Formula 10 and Formula 11,

n is an integer of 7-30.

[Formula 12]

[Formula 13]

In Chemical Formula 12 and Chemical Formula 13,                     

R ¹³ are each independently an alkyl group having 1 to 12 carbon atoms,

k is an integer of 1-3.

[Formula 14]

[Formula 15]

Preferably, the terminator is p-butylphenol, p-cumylphenol, p-phenylphenol, the compound represented by the formula (12), the compound represented by the formula (13), the compound represented by the formula (14) or the It is preferable to use a compound represented by the formula (15).

The terminator is preferably included in an amount of 0.01 to 10 mol% based on 1 mol of the aromatic dihydroxy compound used as a starting material for the transesterification reaction of the present invention.

All of the terminating agent may be added in advance to the transesterification reaction, or some may be added in advance and the rest may be added as the reaction proceeds. In some cases, after some transesterification of the aromatic dihydroxy compound and the diaryl carbonate is carried out, all of the terminal stoppers may be added.

The antioxidant is preferably to use a phosphorus antioxidant, for example trimethyl phosphite, triethyl phosphite, tributyl phosphite, trioctyl phosphite, trinonyl phosphite, tridecyl phosphite, trioctadecyl phosph Trialkyl phosphites such as fighter, distearyl pentaerythritol diphosphite, tris (2-chloroethyl) phosphite, or tris (2,3-dichloropropyl) phosphite; Tricycloalkyl phosphites such as tricyclohexyl phosphite; Triaryl phosphites such as triphenyl phosphite, tricresyl phosphite, tris (ethylphenyl) phosphite, tris (butylphenyl) phosphite, tris (nonylphenyl) phosphite, or tris (hydroxyphenyl) phosphite ; Monoalkyl diaryl phosphites such as 2-ethylhexyl diphenyl phosphite; Trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, tridecyl phosphate, trioctadecyl phosphate distearyl pentaerythritol diphosphate, tris (2-chloroethyl) phosphate, or tris (2,3-dichloropropyl Trialkyl phosphates such as phosphate; Tricycloalkyl phosphates such as tricyclohexyl phosphate; Or triaryl phosphates such as triphenyl phosphate, tricresyl phosphate, tris (nonylphenyl) phosphate, or 2-ethylphenyl diphenyl phosphate.

In the preparation of the siloxane copolycarbonate resin of the present invention, the transesterification reaction is carried out in the presence of the polymerization catalyst, the aromatic dihydroxy compound and the diaryl carbonate, and at this time, additives such as end stoppers, branching agents, antioxidants, etc. It may be added additionally.

The end stoppers, branching agents, antioxidants and the like can be added in the form of powders, liquids, gases, etc., and these serve to improve the quality of the siloxane-based copolycarbonate resins obtained.

Although the reaction temperature in the transesterification reaction is not particularly limited, it is preferably carried out at a temperature of 100 to 330 ℃, preferably at a temperature of 180 to 300 ℃, more preferably gradually with the progress of the reaction It is advisable to raise the temperature from 180 to 300 ° C. If the reaction temperature is less than 100 ℃ can lower the rate of transesterification reaction, if larger than 330 ℃ there is a problem that can be colored by the side reaction or the produced siloxane copolycarbonate resin.

The reaction pressure during the transesterification reaction is not particularly limited, and can be adjusted according to the vapor pressure and the reaction temperature of the monomers used, but in the initial stage of the reaction, it is to be pressurized to an atmospheric pressure (atmospheric pressure) of 1 to 10 atm, and after the reaction In the decompression state to finally be 0.1 to 100 mbar.

In addition, the reaction time during the transesterification reaction can be carried out until the target weight average molecular weight is usually 1,500 to 20,000 g / mol, it is usually carried out for 0.2 to 10 hours.

The transesterification reaction is usually carried out in the absence of an inert solvent, but may be carried out in the presence of an inert solvent corresponding to 1 to 150% by weight of the siloxane copolycarbonate resin obtained as necessary. Examples of the inert solvent include aromatic compounds such as diphenyl ether, halogenated diphenyl ether, benzophenone, polyphenylene ether, dichlorobenzene, and methylnaphthalene; Or cycloalkanes such as tricyclo (5,2,10) decane, cyclooctane, cyclodecane and the like can be used.

In addition, it may be carried out under an inert gas atmosphere if necessary, and examples of the inert gas include gases such as argon, carbon dioxide, dinitrogen monoxide and nitrogen; Chlorofluoro hydrocarbons, alkanes such as ethane or propane, or alkenes such as ethylene or propylene and the like.

Phenols or esters thereof corresponding to diallylcarbonate used as the transesterification reaction proceeds under the above conditions; And inert solvent is stripped from the reactor. Such detachment may be separated, purified, and regenerated. The transesterification can be carried out batchwise or continuously using any apparatus. At this time, the reaction apparatus of the transesterification reaction can be used as long as it has a normal stirring function, it is good to have a high viscosity type stirring function by increasing the viscosity in the reaction later.

Also preferred types of reactors are vessel type or extruder type.

Second step: condensation polymerization reaction step

The low molecular weight siloxane copolycarbonate prepolymer having a weight average molecular weight of 1,500 to 20,000 g / mol prepared through the transesterification reaction is decompressed to a high temperature or condensation-polymerized under nitrogen injection to remain in an unreacted state after the transesterification. To remove the diaryl carbonate and the reaction by-products of low polymerization degree of less than 3 degree of polymerization and the reaction by-products such as phenol newly generated during the reaction, to prepare a molecular weight amorphous siloxane copolycarbonate of increased molecular weight.

In the condensation reaction, in addition to phenol, which is a reaction byproduct, unreacted diaryl carbonate and a reaction by-product of less than 3 degree of polymerization that are not participating in the reaction are evaporated together with phenol and extracted out of the reactor. In comparison, the solid phase polymerization has the effect of promoting the increase in molecular weight of the polycarbonate.

In addition, in the conventional process, not only the diaryl carbonate used in excess in the transesterification step and the reaction byproducts having a polymerization degree of less than 3 are removed through the condensation polymerization step before the solid phase polymerization as in the present invention, and consequently, the molecular weight of the prepolymer. With the increase, the molar ratio of the resulting prepolymer-terminated aryl carbonate and aromatic hydroxy becomes large, and thus a long time is required to prepare a high molecular weight polycarbonate in solid phase polymerization.

The condensation polymerization reaction of the present invention can use all of the common condensation reactor, for example a rotating disk reactor (rotating disk reactor) or a rotating cage reactor (rotating cage reactor), in addition to the thin film reactor (Thin film reactor) ) Can be used.

In this case, the reaction temperature is preferably 180 to 330 ° C, more preferably 200 to 300 ° C.

In addition, the condensation polymerization reaction is a dialkyl (aryl) carbonate present in the unreacted state after the transesterification reaction and the reaction by-product of the polymerization degree less than 3 and the newly generated by-product phenol as described above and 0 to 50 mmHg. Under reduced pressure, more preferably 0 to 20 mmHg under reduced pressure.

According to one embodiment of the present invention, it may be carried out while removing the reaction by-products by nitrogen injection instead of the reduced pressure, wherein the amount of nitrogen injected is preferably 0.01 to 1.0 Nm ³ / kg ㅇ h. The reaction time may vary depending on the reaction conditions, but generally 2 to 120 minutes is preferred.

The medium molecular weight amorphous siloxane copolycarbonate prepolymer prepared by the above process preferably has a weight average molecular weight of 10,000 to 30,000 g / mol.

Phase 3: Crystallization and Solid State Polymerization

A high molecular weight siloxane copolycarbonate resin is prepared by solid phase polymerizing a siloxane copolycarbonate having a weight average molecular weight of 10,000 to 30,000 g / mol prepared through the condensation polymerization reaction.

The siloxane-based copolycarbonate prepolymer prepolymerized by transesterification and condensation polymerization as described above is prepared by heating to a solid phase under an inert gas atmosphere or under reduced pressure, that is, by solid-phase polymerization to produce a high molecular weight siloxane-based copolycarbonate resin. do.

The weight average molecular weight (Mw) of the medium molecular weight siloxane copolycarbonate prepolymer used in the solid phase polymerization is preferably 10,000 to 30,000, more preferably 13,000 to 25,000. If the weight average molecular weight is less than 10,000, there is a problem in that it requires a long reaction time during the solid phase polymerization.

In this case, if necessary, the step of crystallizing the siloxane copolycarbonate prepolymer may be further performed before the solid phase polymerization. The crystallization treatment is carried out in order to increase the melting point of the siloxane copolycarbonate prepolymer by crystallization and to prevent fusion of the siloxane copolycarbonate prepolymer during solid phase polymerization.

There is no restriction | limiting in particular in the said crystallization processing method, Although various methods can be used, it is preferable to carry out especially by a solvent treatment method or a heat crystallization method.

In the solvent treatment method, after dissolving the siloxane copolycarbonate prepolymer in a suitable solvent, the solvent is evaporated, and a semi-solvent for the siloxane copolycarbonate prepolymer is added to precipitate a solid siloxane copolycarbonate prepolymer, Alternatively, the siloxane copolycarbonate prepolymer may be contacted with a liquid solvent or a solvent vapor having a low solubility for the siloxane copolycarbonate prepolymer to penetrate the solvent into the siloxane copolycarbonate prepolymer to crystallize.

Preferred solvents for the solvent treatment of such siloxane copolycarbonate prepolymers include chloromethane, methylene chloride, chloroform, carbon tetrachloride, chloroethane, dichloroethane (various), trichloroethane (various), trichloroethylene, or Aliphatic halogen hydrocarbons such as tetrachloroethane (various); Aromatic hydrogenated hydrocarbons such as chlorobenzene or dichlorobenzene; Ether compounds such as tetrahydrofuran or dioxane; Ester compounds such as methyl acetate or ethyl acetate; Ketone compounds such as acetone or methyl ethyl ketone; Aromatic hydrocarbons such as benzene, toluene, or xylene.

The amount of the solvent used for the solvent treatment is different depending on the type of siloxane copolycarbonate prepolymer or solvent, the required degree of crystallization, the treatment temperature, etc., but preferably 0.05 to 100 times the weight of the siloxane copolycarbonate prepolymer, more preferably. Is preferably used 0.1 to 50 times.

On the other hand, the heat crystallization method is a method of crystallizing by heating the glass transition temperature of the siloxane copolycarbonate resin to obtain the siloxane copolycarbonate prepolymer to a range below the temperature at which the siloxane copolycarbonate prepolymer starts to melt. . The method can be crystallized by simply heating the siloxane copolycarbonate prepolymer, which is a very easy method.

The temperature Tc (° C.) for performing such heat crystallization is preferably in the range from the glass transition temperature (Tg) of the siloxane copolycarbonate resin to be obtained to the melting temperature Tm (° C.) of the siloxane copolycarbonate prepolymer. In particular, since the crystallization rate of the siloxane copolycarbonate prepolymer is low at low temperatures, the preferable heat crystallization temperature Tc (° C.) is preferably in the range represented by the following equation (3).                     

[Equation 3]

Tm-50 ≤ Tc ≤ Tm

The heating crystallinity of the siloxane copolycarbonate prepolymer may be carried out while maintaining a constant temperature in the range of Equation 3, may be carried out while changing the temperature continuously or discontinuously, or may be carried out by mixing them have. As the method of changing the temperature, the melting temperature of the siloxane copolycarbonate prepolymer generally increases as the heat crystallization progresses. At this time, it is preferable to heat-crystallize while raising the temperature at the same rate as the rising temperature.

The method of heating crystallization while changing the temperature as described above has the advantage that the crystallization rate of the siloxane-based copolycarbonate prepolymer is faster and the melting temperature can be higher than that of the heating crystallization method performed at a constant temperature.

The time of heat crystallization is different depending on the chemical composition of the siloxane copolycarbonate prepolymer, the presence or absence of a catalyst, the crystallization temperature, the crystallization method, and the like, but it is preferably performed for 1 to 200 hours.

In the solid phase polymerization, the catalyst used during the prepolymerization remains so that the polymerization can be carried out without adding a catalyst. The monohydroxy compound or aryl carbonate produced by the solid phase polymerization can be reacted by extracting it out of the reaction system. Can be promoted. As a method for extracting the monohydroxy compound or the aryl carbonate out of the reaction system, an inert gas such as nitrogen, argon, helium or carbon dioxide, a lower hydrocarbon gas, or the like is introduced, and the monohydroxy compound or the aryl carbonate is introduced into the gas. May be used in combination with a method of removing the same, a method of carrying out the reaction under reduced pressure, or a combination thereof. In addition, when introducing a companion gas (inert gas, lower hydrocarbon gas), it is preferable to heat the gas to a temperature near the reaction temperature in advance.

The form of the siloxane copolycarbonate prepolymer used in the solid phase polymerization is not particularly limited, but the bulky siloxane copolycarbonate prepolymer has a pellet shape, a bead shape, a granule shape, and a powder shape because it delays the reaction rate and is difficult to handle. Preferred are siloxane copolycarbonate prepolymers. In addition, the solid siloxane copolycarbonate prepolymer may be crushed to an appropriate size to be used. In particular, siloxane-based copolycarbonate prepolymers crystallized by solvent treatment after the prepolymerization are usually obtained in the form of porous granules or powders, and these porous siloxane-based copolycarbonate prepolymers are monohydroxy which are by-products in the case of solid phase polymerization. The extraction of the compound or aryl carbonate is preferred since it is easy.

In addition, the solid phase polymerization may further use additives such as powders, liquids, or gaseous end stoppers, branching agents, antioxidants, and the like, which have an effect of improving the quality of the resulting siloxane copolycarbonate resin. Do it.

The reaction temperature Tp (° C.) and the reaction time during the solid phase polymerization may include the type (chemical structure, molecular weight, etc.) or type of the siloxane-based copolycarbonate prepolymer, the type or amount of the catalyst, the crystallinity or the melting temperature Tm of the siloxane-based copolycarbonate prepolymer. May vary according to (° C.). In addition, although the degree of polymerization or other reaction conditions of the desired siloxane copolycarbonate resin may vary, the polycarbonate prepolymer may not be melted from the glass transition temperature (Tg) of the desired siloxane copolycarbonate resin. It is preferable that it is a range up to the temperature which maintains a solid phase without. More preferably, it is preferably performed for 1 minute to 100 hours, most preferably 0.1 minutes to 50 hours.

[Equation 4]

Tm'-50 ≤ Tp ≤ Tm '

As the temperature range, for example, when preparing a siloxane copolycarbonate resin of bisphenol A, solid phase polymerization is preferably performed at 150 to 260 ° C, more preferably at 180 to 230 ° C.

In order to give uniform heat to the polymer during the polymerization during the solid phase polymerization, or to facilitate extraction of the by-product monohydroxy compound or aryl carbonate, a method using a stirring blade, a reactor having a structure in which the reactor itself rotates It is preferable to use a stirring method such as a method or a method of flowing with a heating gas.

The weight average molecular weight (Mw) of the siloxane copolycarbonate resin obtained by solid state polymerization as mentioned above is 20,000-200,000, Preferably it is 30,000-100,000. The siloxane copolycarbonate resin of the present invention having the above weight average molecular weight can be usefully used for industrial purposes.

The shape of the siloxane copolycarbonate resin obtained by the solid phase polymerization may vary depending on the shape of the siloxane copolycarbonate prepolymer used, but is usually a powder such as beads, granules, or powder. In addition, the crystallinity of the obtained siloxane copolycarbonate is usually higher than that of the siloxane copolycarbonate prepolymer. That is, the siloxane copolycarbonate resin prepared according to the present invention is a crystalline resin in powder form. In addition, the crystalline resin in the form of powder homogenized to a predetermined molecular weight by solid phase polymerization may be introduced into the compressor as it is, without being cooled, or pelletized, or may be introduced into a molding machine without cooling to be molded.

The reaction apparatus used in the preliminary polymerization, crystallization, and solid phase polymerization carried out to prepare the siloxane-based copolycarbonate resin of the present invention may be batch, fluidized, or a combination thereof. In addition, in general, prepolymerization is to prepare a relatively low molecular weight siloxane-based copolycarbonate prepolymer, whereas in the present invention, prepolymerization by transesterification does not require an expensive reactor for high viscosity fluids required for high temperature melt polymerization. In addition, the crystallization process may crystallize the siloxane-based copolycarbonate prepolymer by solvent treatment or heat treatment, and no special apparatus is required. Solid phase polymerization can also be polymerized with any device that can substantially heat the siloxane-based copolycarbonate prepolymer and remove by-product monohydroxy compounds or arylcarbonates.

Hereinafter, preferred examples are provided to help understanding of the present invention, but the following examples are merely to illustrate the present invention, and the scope of the present invention is not limited to the following examples.                     

Example

Example 1

(Preparation of amorphous siloxane copolycarbonate prepolymer)

1,484 g (6.50 mole), 1478 g (6.90 mole), and 5.08 g (1.13 × 10 ^-3 mole) of bisphenol-A, diphenyl carbonate, and polysiloxane (Dow Corning 3058) were mixed together into a reactor under a nitrogen atmosphere. After injection, sodium acetate and tetrabutylphosphonium hydroxide were injected into the polymerization catalyst at a molar concentration of 1 × 10 ⁻⁶ and 2.5 × 10 ⁻⁴ , respectively, based on bisphenol-A, followed by stirring at a jacket temperature of 230 ° C. The reaction was carried out for 5 minutes. Then, a low molecular weight amorphous siloxane copolycarbonate prepolymer having a weight average molecular weight of 9,095 g / mol was subjected to esterification and transesterification for 30 minutes under a reduced pressure of 1 to 4 mmHg.

(Preparation of amorphous siloxane copolycarbonate through condensation polymerization reaction)

Condensation polymerization of polycarbonate was carried out in a thin film reactor in which the temperature of the reactor was set at 300 ° C. and the reaction pressure was adjusted to 1 mmHg or less so that the low molecular weight amorphous siloxane-based copolycarbonate prepolymer was maintained for 30 minutes. To proceed, a medium molecular weight amorphous siloxane copolycarbonate having a weight average molecular weight of 15,659 g / mol was prepared.

(Manufacture of crystalline siloxane copolycarbonate)

The prepared medium-molecular weight amorphous siloxane copolycarbonate was dissolved in methylene chloride at a temperature of 0.15 g / mL at room temperature, and 100% methanol was used as a non-solvent. Polycarbonate was obtained as a precipitate.

(Manufacture of high molecular weight crystalline siloxane copolycarbonate)

The powdered crystalline siloxane copolycarbonate prepared above was injected into a solid phase polymerization reactor, and the solid phase polymerization reaction was performed under a reduced pressure of 1 mmHg at 200 ° C isothermal conditions. The results are shown in Table 1.

Comparative Example 1

(Manufacture of crystalline siloxane copolycarbonate)

A powdery crystalline siloxane copolycarbonate was prepared in the same manner as in Example 1, except that the condensation polymerization step was not performed in Example 1.

(Manufacture of high molecular weight crystalline siloxane copolycarbonate resin)

The powdery crystalline siloxane copolycarbonate prepared above was subjected to solid phase polymerization in the same manner as in Example 1, and the results are shown in Table 1.

Solid State Polymerization Time Example 1 Comparative Example 1 0 15,659 9,095 2 33,227 30,448 4 35,767 31,356 6 37,817 33,693 8 37,914 34,246 10 38,726 34,734

Through the above Example 1 and Comparative Example 1, after the condensation polymerization reaction of the low molecular weight amorphous siloxane-based copolycarbonate prepolymer according to the present invention, the high-molecular-weight crystalline siloxane copolymer of Example 1 The carbonate could not be obtained within 10 hours by the conventional solid phase polymerization process compared with the high molecular weight crystalline siloxane copolycarbonate of Comparative Example 1 prepared according to the conventional process where the solid phase polymerization was carried out without the condensation polymerization reaction. A siloxane copolycarbonate resin having a weight average molecular weight of 35,000 g / mol or more could be produced within 4 hours.

The production method of the siloxane copolycarbonate of the present invention introduces a pressure reduction condensation reaction step to shorten the reaction time of the solid phase polymerization reaction step, and does not use toxic chemicals, so there is no risk, and it is possible to prevent quality deterioration. There is.

Claims (13)

a) melting and transesterifying the diaryl carbonate, the aromatic dihydroxy compound, and the polysiloxane under a catalyst to prepare a low molecular weight amorphous siloxane copolycarbonate prepolymer having a weight average molecular weight of 1,500 to 20,000 g / mol; b) condensation polymerization of the low molecular weight amorphous siloxane copolycarbonate prepolymer of step a) to produce a medium molecular weight amorphous siloxane copolycarbonate having a weight average molecular weight of 10,000 to 30,000 g / mol; c) preparing a crystalline siloxane copolycarbonate from the medium molecular weight amorphous siloxane copolycarbonate of step b); And d) solid-phase polymerization of the crystalline siloxane copolycarbonate of step c) to prepare a high molecular weight siloxane copolycarbonate having a weight average molecular weight of 20,000 to 200,000 g / mol. Method for producing a polycarbonate resin. The method for producing a high molecular weight siloxane copolycarbonate resin according to claim 1, wherein the aromatic dihydroxy compound used in step a) is a compound represented by the following Formula 1.

(One) (In Formula 1, R ¹ and R ² are each independently a halogen atom or an alkyl group having 1 to 8 carbon atoms; a and b are each independently an integer of 0 to 4; Z is an alkylene group having 1 to 8 carbon atoms, an alkylidene group having 2 to 8 carbon atoms, a cycloalkylene group having 5 to 15 carbon atoms, a cycloalkylidene group having 5 to 15 carbon atoms, -S, -SO-, -SO _2- , -O-, -CO-, a compound represented by the following formula 2 or a compound represented by the following formula 3)

(2)

(3) The method for producing a high molecular weight siloxane copolycarbonate resin according to claim 1, wherein the diaryl carbonate used in step a) is a compound represented by the following Formula 4 or a compound represented by the following Formula 5.

(4) (In Formula 4, Ar ¹ and Ar ² are each independently an aryl group)

(5) (In Formula 5, Ar ³ and Ar ⁴ are each independently an aryl group, D ¹ is two from the aromatic dihydroxy compound represented by the formula (1) of claim 2 Residues obtained by removing hydroxyl groups). The method for producing a high molecular weight siloxane copolycarbonate resin according to claim 1, wherein the polysiloxane compound used in step a) is a compound represented by the following Formula 6.

(6) (In Formula 6, n is an integer of 1 to 500, R ³ , R ^{3 '} , R ⁴ and R ^4' are each independently a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and some or all of the hydrogen atoms of the alkyl group are independently Can be substituted with halogen atoms, R ⁵ and R ⁶ are each independently a linear or branched alkylene group having 1 to 20 carbon atoms, a monocyclic or polycyclic arylene group having 6 to 30 carbon atoms, or -R ⁷ -XR ^8- , R ⁷ and R ⁸ are each independently a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, or a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, X is -O-, -S-, -SO-, -CO-.) The method for producing a high molecular weight siloxane copolycarbonate resin according to claim 1, wherein the polysiloxane compound used in step a) is a compound represented by the following Formula 7.

(7) (Wherein x is an integer of 1 to 500) The method for producing a high molecular weight siloxane copolycarbonate resin according to claim 1, wherein the diaryl carbonate is 1.0 to 1.5 moles with respect to 1 mole of the dihydroxy compound. The method for producing a high molecular weight siloxane copolycarbonate resin according to claim 1, wherein the polysiloxane compound contains 0.01 to 20 mol% of siloxane repeating units in 1 mol of the dihydroxy compound. The method of claim 1, wherein the catalyst is a metal compound catalyst system and a non-metal compound catalyst system, each of which is used independently or mixed. 8. The metal compound catalyst system of claim 7, wherein the metal compound catalyst system comprises a salt compound such as hydroxide, acetate, alkoxide, carbonate, hydride, hydroxide, or oxide of an alkali or alkaline earth metal and a transition metal such as zinc, cadmium, titanium, or lead. The organometallic compound and aluminum hydride or borohydride containing the method of producing a high molecular weight siloxane copolycarbonate resin. The method of claim 7, wherein the nonmetallic compound catalyst system is tetramethyl ammonium hydroxide, tetramethyl ammonium acetate, tetramethyl ammonium formate, tetramethyl ammonium carbonate, tetraethyl ammonium hydroxide, tetrapropyl ammonium hydroxide, tetrabutyl Quaternary ammonium salts such as ammonium hydroxide, tetraphenyl ammonium hydroxide and trimethylphenyl ammonium hydroxide; Tetramethyl phosphonium hydroxide, tetramethyl phosphonium acetate, tetramethyl phosphonium formate, tetramethylphosphonium carbonate, tetraethyl phosphonium hydroxide, tetrapropyl phosphonium hydroxide, tetrabutyl phosphonium hydroxide Quaternary phosphonium salts such as tetraphenyl phosphonium hydroxide and trimethylphenyl phosphonium hydroxide; Primary, secondary or tertiary amine compounds; Or an aromatic compound derivative containing nitrogen, such as pyridine. The method of claim 7, wherein the metal compound catalyst system is contained in 10 ^-3 to 10 ^-8 mole and the non-metal compound catalyst system is contained in 10 ^-1 to 10 ^-6 mole with respect to 1 mole of the aromatic dihydroxy compound. Method for producing a high molecular weight siloxane copolycarbonate resin. The method of claim 1, wherein the step b) is performed in a reactor selected from the group consisting of a rotating disk reactor, a rotating cage reactor and a thin film reactor. A method for producing a high molecular weight siloxane copolycarbonate resin. A siloxane copolycarbonate resin produced by the method of any one of claims 1 to 12.