JP5998568B2 - Method for producing polycarbonate resin composition - Google Patents

Description

  The present invention relates to a method for producing a polycarbonate resin composition, and more particularly, to a method for producing a polycarbonate resin composition in which a molten polycarbonate resin and an additive are supplied to an extruder and kneaded.

  As a method for producing a polycarbonate resin, a melting method in which a dihydroxy compound and a carbonic acid diester are polycondensed is known.

  As described in Patent Document 1, the polycarbonate resin produced by this method comes out of the polycondensation device in a molten state and is sent to a kneading extrusion device, where volatile components contained therein are removed as exhaust gas. At the same time, various additives are kneaded to obtain a polycarbonate resin composition as a product.

JP 2005-146050 A

  By the way, the kneading and extruding apparatus has at least a molten polycarbonate resin supply part, an additive supply part, a kneading part, a vent part for performing exhaust gas treatment, and a stabilization part. For this reason, it takes too much time for the molten polycarbonate resin to pass through the kneading extrusion apparatus, and it is exposed to high temperatures for a long time, or it takes too much heat. There is a tendency to deteriorate.

  On the other hand, by increasing the rotation of the screw of the kneading and extruding apparatus, the time spent in the kneading and extruding apparatus can be reduced. However, in this case, the screw shear becomes too strong, and on the contrary, the resin temperature rises, resulting in deterioration of quality.

  Accordingly, an object of the present invention is to maintain the quality of the obtained polycarbonate resin.

  The present invention is a method for producing a polycarbonate resin composition in which a molten polycarbonate resin and an additive are supplied to a kneading and extruding apparatus and kneaded, and the kneading and extruding apparatus requires kneading per unit mass of the polycarbonate resin composition. Since the specific energy is 0.03 kWh / kg or more and 0.08 kWh / kg or less, and the L / D (L: screw length, D: cylinder inner diameter) of the kneading and extruding apparatus is 30 or less, the above-mentioned problem has been achieved. is there.

  According to the present invention, the kneading and extruding device has an L / D (screw length / cylinder inner diameter) of a predetermined value or less and the specific energy required for kneading of the kneading and extruding device, that is, the rotation of the screw of the kneading and extruding device. Since the work for the target molten polycarbonate resin and additives is within a predetermined range, a polycarbonate resin composition having stable quality, particularly color tone, and little change in color tone with time can be stably produced.

Schematic diagram showing an example of a kneading extrusion device used in the present invention

Hereinafter, embodiments of the present invention will be described in detail.
The present invention relates to a method for producing a polycarbonate resin composition in which a melted polycarbonate resin and an additive are supplied to a kneading extrusion apparatus and kneaded.

(Polycarbonate resin)
The polycarbonate resin is preferably a polymer compound produced by polycondensation reaction (ester exchange reaction) of a carbonic acid diester and a dihydroxy compound.

(Carbonated diester)
Examples of the carbonic acid diester include substituted diphenyl carbonates such as diphenyl carbonate (DPC) and ditolyl carbonate, and dialkyl carbonates such as dimethyl carbonate, diethyl carbonate, and di-t-butyl carbonate. These carbonic acid diesters can be used alone or in admixture of two or more.

  These carbonic acid diesters are used in excess relative to the aromatic dihydroxy compound. That is, the carbonic acid diester is used in an amount of 1.01 to 1.30 times (molar ratio), preferably 1.02 to 1.20 times (molar ratio) with respect to the aromatic dihydroxy compound. When the molar ratio is too small, the terminal hydroxyl groups of the resulting aromatic polycarbonate increase, and the thermal stability of the polycarbonate resin composition tends to deteriorate. On the other hand, if the molar ratio is too large, the reaction rate of the transesterification reaction decreases, making it difficult to produce a polycarbonate resin having a desired molecular weight, or increasing the residual amount of carbonic acid diester in the polycarbonate resin composition. It may cause odor when processed or molded.

(Dihydroxy compound)
The dihydroxy compound is a compound having two hydroxyl groups in the molecule. In the present invention, among the dihydroxy compounds, the molecule has one or more aromatic rings, and the two hydroxyl groups are bonded to the aromatic rings, respectively. It is preferred to use the aromatic dihydroxy compound prepared.

  Specific examples of such aromatic dihydroxy compounds include, for example, bis (4-hydroxydiphenyl) methane, 2,2-bis (4-hydroxyphenyl) propane, and 2,2-bis (4-hydroxy-3-methyl). Phenyl) propane, 2,2-bis (4-hydroxy-3-tert-butylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (4- Bisphenols such as hydroxy-3,5-dibromophenyl) propane, 4,4-bis (4-hydroxyphenyl) heptane, 1,1-bis (4-hydroxyphenyl) cyclohexane; 4,4′-dihydroxybiphenyl, 3 , 3 ′, 5,5′-tetramethyl-4,4′-dihydroxybiphenyl and the like; bis (4-hydroxy Eniru) sulfone, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) ether, bis (4-hydroxyphenyl) ketone. Among these, 2,2-bis (4-hydroxyphenyl) propane (that is, bisphenol A (BPA)) is preferable. These aromatic dihydroxy compounds can be used alone or in admixture of two or more.

(Transesterification catalyst)
In the transesterification reaction, a transesterification catalyst is used. Examples of the transesterification catalyst include a catalyst usually used for producing a polycarbonate resin by a transesterification method, and are not particularly limited. Generally, basic compounds such as compounds of Group 1 elements (excluding hydrogen), compounds of Group 2 elements, basic boron compounds, basic phosphorus compounds, basic ammonium compounds, and amine compounds are generally used. Can be mentioned.
Among these transesterification catalysts, practically, at least one compound selected from the group consisting of compounds of Group 1 elements (excluding hydrogen) and compounds of Group 2 elements is preferred. These transesterification catalysts may be used alone or in combination of two or more.

  The transesterification catalyst is generally used in an amount of 0.2 to 2.0 micromole, preferably 0.5 to 1.0 micromole per 1 mol of the aromatic dihydroxy compound. .

  The group 1 element (excluding hydrogen) includes an inorganic compound such as a hydroxide, carbonate, hydrogen carbonate compound, etc. of the group 1 element (excluding hydrogen); Group 1 element (excluding hydrogen) Organic compounds such as salts with alcohols, phenols, and organic carboxylic acids. Here, as a group 1 element (except hydrogen), lithium, sodium, potassium, rubidium, and cesium are mentioned, for example. Among these group 1 elements (excluding hydrogen), cesium compounds are preferable, and cesium carbonate, cesium hydrogen carbonate, and cesium hydroxide are particularly preferable.

  Examples of the Group 2 element compounds include hydroxides such as beryllium, magnesium, calcium, strontium, and barium; inorganic compounds such as carbonates; and alcohols, phenols, and organic carboxylic acids. Examples include salts.

  Examples of the basic boron compound include sodium salts, potassium salts, lithium salts, calcium salts, magnesium salts, barium salts, and strontium salts of boron compounds. Here, as the boron compound, for example, tetramethylboron, tetraethylboron, tetrapropylboron, tetrabutylboron, trimethylethylboron, trimethylbenzylboron, trimethylphenylboron, triethylmethylboron, triethylbenzylboron, triethylphenylboron, tributyl Examples include benzylboron, tributylphenylboron, tetraphenylboron, benzyltriphenylboron, methyltriphenylboron, and butyltriphenylboron.

  Examples of the basic phosphorus compound include trivalent phosphorus compounds such as triethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triphenylphosphine, and tributylphosphine, or the like. And quaternary phosphonium salts derived from these compounds.

  Examples of the basic ammonium compound include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, trimethylbenzylammonium hydroxide, trimethylphenylammonium hydroxide. Side, triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, Le triphenyl ammonium hydroxide, butyltriphenyl ammonium hydroxide, and the like.

  Examples of the amine compound include 4-aminopyridine, 2-aminopyridine, N, N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 2-hydroxypyridine, 2-methoxypyridine, 4- Examples include methoxypyridine, 2-dimethylaminoimidazole, 2-methoxyimidazole, imidazole, 2-mercaptoimidazole, 2-methylimidazole, and aminoquinoline.

(Manufacture of polycarbonate resin composition)
Next, the manufacturing method of a polycarbonate resin composition is demonstrated.
The polycarbonate resin is prepared by preparing a mixture of the above-mentioned dihydroxy compound and carbonic acid diester compound, which are raw materials, using a raw material preparation device (raw material preparation step), and then using the polycondensation reaction device in the presence of the transesterification reaction catalyst. A polycondensation reaction is performed (polycondensation step), and an additive or the like is added to the polycarbonate resin obtained in the polycondensation step to obtain a polycarbonate resin composition (kneading step).

(Polycondensation process)
A polycarbonate resin is obtained by subjecting the raw material mixture obtained in the raw material preparation step to polycondensation in a batch system, a continuous system, or a combination thereof. As an example of this polycondensation step, there is a method of performing a polycondensation reaction in multiple stages using a multistage polycondensation reaction apparatus. The number of stages is preferably 2 or more, preferably 3 to 7 stages. Specific conditions for the polycondensation reaction are temperature: 150 ° C. to 320 ° C., pressure: normal pressure to 0.01 Torr (1.3 Pa), and average residence time: 5 minutes to 300 minutes.

  In the multi-stage system, in order to more effectively remove monohydroxy compounds such as phenol as a by-product as the polycondensation reaction proceeds out of the system with the progress of the polycondensation reaction, the reaction temperature is increased stepwise. Set to a higher vacuum. In order to prevent quality deterioration such as hue of the obtained polycarbonate resin, it is preferable to set a low temperature and a short residence time as much as possible.

  When the polycondensation step is performed in a multistage manner, it is usually preferable to increase the average molecular weight of the polycarbonate resin by providing a plurality of vertical reactors followed by 1 to 2 horizontal reactors. Usually, the total number of reactors installed is 3 to 6 units, preferably 4 to 5 units.

  The reason why the horizontal reactor is used as a subsequent reactor in a group of polycondensation reactors is that the viscosity increases as the polycondensation reaction proceeds. This is to make the stirring of the above easier.

  Examples of the vertical and horizontal reactors include, for example, a stirred tank reactor, a thin film reactor, a centrifugal thin film evaporation reactor, a surface renewal biaxial kneading reactor, a biaxial horizontal stirred reactor, and a wet wall type A reactor, a perforated plate type reactor that polymerizes while freely dropping, a perforated plate type reactor with wire that polymerizes while dropping along a wire, and the like are used.

  Examples of the type of stirring blades in the vertical reactor include turbine blades, paddle blades, fouler blades, anchor blades, full zone blades (manufactured by Shinko Pantech Co., Ltd.), and Sun Meller blades (manufactured by Mitsubishi Heavy Industries, Ltd.). ), Max blend wing (manufactured by Sumitomo Heavy Industries, Ltd.), helical ribbon wing, twisted lattice wing (manufactured by Hitachi, Ltd.), and the like.

  By the way, the horizontal reactor refers to a reactor in which a rotating shaft of a stirring blade is a horizontal type (horizontal direction). As a stirring blade of a horizontal reactor, for example, a single-shaft type stirring blade such as a disk type or a paddle type, HVR, SCR, N-SCR (manufactured by Mitsubishi Heavy Industries, Ltd.), Vivolak (Sumitomo Heavy Industries, Ltd.) Or a biaxial stirring blade such as a spectacle blade or a lattice blade (manufactured by Hitachi, Ltd.).

In addition, the transesterification catalyst used for the polycondensation of a dihydroxy compound and a carbonic acid diester is usually prepared in advance as an aqueous solution. The concentration of the catalyst aqueous solution is not particularly limited, and is adjusted to an arbitrary concentration according to the solubility of the catalyst in water. Moreover, it can replace with water and other solvents, such as acetone, alcohol, toluene, and phenol, can also be selected.
The properties of water used for dissolving the catalyst are not particularly limited as long as the type and concentration of impurities contained are constant, but usually distilled water, deionized water, and the like are preferably used.

(Kneading process)
The polycarbonate resin A obtained in the polycondensation step is sent to a kneading and extruding apparatus 11 as shown in FIG. 1 in a molten state and kneaded with additives and the like to obtain a polycarbonate resin composition. Examples of the kneading and extruding apparatus 11 include a twin screw extruder and a single screw extruder, but a twin screw extruder is preferable because of good kneadability.

  The kneading and extruding apparatus 11 includes at least a resin supply unit 12 that supplies the molten polycarbonate resin, an additive supply unit 13, a kneading unit 14 that performs kneading, and devolatilization of volatile components including unreacted raw materials and reaction byproducts. It comprises a vent part 15 to be performed and a stabilizing part 16.

  In the additive supply unit 13, an additive or the like is supplied. These additives include transesterification catalyst deactivators, mold release agents, heat stabilizers, UV absorbers, bluing agents, antistatic agents, flame retardants, heat ray shielding agents, fluorescent dyes (including fluorescent whitening agents). Pigments, light diffusing agents, reinforcing fillers, and the like. In addition, when the recovered polycarbonate resin or polycarbonate resin composition is reused, it is supplied together with additives. As this additive, not only powdery and solid additives but also liquid or heated and melted additives may be used.

  As a mold release agent, what consists of ester compound of alcohol and a fatty acid is mentioned. Specific examples of the ester compound of alcohol and fatty acid include a monohydric alcohol and fatty acid ester compound and / or a partial ester compound of polyhydric alcohol and fatty acid or a total ester compound. The monohydric alcohol and fatty acid ester compound is preferably an ester compound of a monohydric alcohol having 1 to 20 carbon atoms and a saturated fatty acid having 10 to 30 carbon atoms. The partial ester or total ester compound of a polyhydric alcohol and a fatty acid is preferably a partial ester compound or a total ester compound of a polyhydric alcohol having 1 to 25 carbon atoms and a saturated fatty acid having 10 to 30 carbon atoms.

  Specific examples of ester compounds of monohydric alcohols and saturated fatty acids include stearyl stearate, palmityl palmitate, butyl stearate, methyl laurate, isopropyl palmitate, and stearyl stearate is preferred.

  Specific examples of partial ester compounds or total ester compounds of polyhydric alcohols and saturated fatty acids include stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride, stearic acid monosorbate, behenic acid monoglyceride, pentaerythritol monostearate, penta All ester compounds of dipentaerythritol, such as erythritol tetrastearate, pentaerythritol tetrapelargonate, propylene glycol monostearate, biphenyl biphenate, sorbitan monostearate, 2-ethylhexyl stearate, dipentaerythritol hexastearate or Examples thereof include partial ester compounds.

  Among these ester compounds, stearic acid monoglyceride, stearic acid triglyceride, pentaerythritol tetrastearate, and a mixture of stearic acid triglyceride and stearyl stearate are preferably used.

  The amount of the ester in the release agent is preferably 90% by weight or more, and more preferably 95% by weight or more when the release agent is 100% by weight.

  The content of the release agent in the polycarbonate resin composition is preferably in the range of 0.005 to 2.0 parts by weight with respect to 100 parts by weight of the polycarbonate resin, and 0.01 to 0.6 parts by weight. Is more preferable, and a range of 0.02 to 0.5 parts by weight is even more preferable.

  Examples of the heat stabilizer include a phosphorus heat stabilizer, a sulfur heat stabilizer, and a hindered phenol heat stabilizer.

  Examples of the phosphorus-based heat stabilizer include phosphorous acid, phosphoric acid, phosphonous acid, phosphonic acid, and ester compounds thereof. Specifically, triphenyl phosphite, tris (nonylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, tris (2,6-di-tert-butylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl monophenyl Phosphite, dioctyl monophenyl phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) Pentaellis Tall diphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) Pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, tributyl phosphate, triethyl phosphate, trimethyl phosphate, triphenyl phosphate, diphenyl monoorthoxenyl phosphate, dibutyl phosphate, dioctyl phosphate, diisopropyl phosphate, dimethyl benzenephosphonate, benzenephosphone Diethyl acetate, dipropyl benzenephosphonate, tetrakis (2,4-di-tert-butylphenyl) -4,4'-biphenylene Phosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,3′-biphenylenediphosphonite, tetrakis (2,4-di-tert-butylphenyl) -3,3′-biphenylenediphosphonite, Examples thereof include bis (2,4-di-tert-butylphenyl) -4-phenyl-phenylphosphonite and bis (2,4-di-tert-butylphenyl) -3-phenyl-phenylphosphonite.

  Among them, tris (2,4-di-tert-butylphenyl) phosphite, tris (2,6-di-tert-butylphenyl) phosphite, tetrakis (2,4-di-tert-butylphenyl) -4 , 4′-biphenylenediphosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,3′-biphenylenediphosphonite, tetrakis (2,4-di-tert-butylphenyl) -3,3 '-Biphenylenediphosphonite, bis (2,4-di-tert-butylphenyl) -4-phenyl-phenylphosphonite and bis (2,4-di-tert-butylphenyl) -3-phenyl-phenylphosphonite And particularly preferably tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylene Phosphonite is used.

  The content of the phosphorous heat stabilizer in the polycarbonate resin composition is preferably 0.001 to 0.2 parts by weight with respect to 100 parts by weight of the polycarbonate resin.

As the sulfur-based heat stabilizer, pentaerythritol-tetrakis (3-laurylthiopropionate), pentaerythritol-tetrakis (3-myristylthiopropionate), pentaerythritol-tetrakis (3-stearylthiopropionate), Examples include dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate, distearyl-3,3′-thiodipropionate, and pentaerythritol-tetrakis (3- Laurylthiopropionate), pentaerythritol-tetrakis (3-myristylthiopropionate), dilauryl-3,3′-thiodipropionate, dimyristyl-3,3′-thiodipropionate. Particularly preferred is pentaerythritol-tetrakis (3-laurylthiopropionate). The thioether compounds are commercially available from Sumitomo Chemical Co., Ltd. as Sumilizer TP-D (trade name), Sumilizer TPM (trade name), and the like, and can be easily used.
As content of the sulfur type heat stabilizer in a polycarbonate resin composition, 0.001 weight part-0.2 weight part are preferable with respect to 100 weight part of polycarbonate resin.
Examples of the hindered phenol heat stabilizer include triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3 , 5-di-tert-butyl-4-hydroxyphenyl) propionate], pentaerythritol-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3 5-di-tert-butyl-4-hydroxyphenyl) propionate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, N, N-hexamethylene bis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamide) 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate and 3,9-bis {1,1- And dimethyl-2- [β- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl} -2,4,8,10-tetraoxaspiro (5,5) undecane. Octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate is particularly preferably used.

  The content of the hindered phenol heat stabilizer in the polycarbonate resin composition is preferably 0.001 to 0.3 parts by weight with respect to 100 parts by weight of the polycarbonate resin.

  The ultraviolet absorber is at least one selected from the group consisting of benzotriazole ultraviolet absorbers, benzophenone ultraviolet absorbers, triazine ultraviolet absorbers, cyclic imino ester ultraviolet absorbers, and cyanoacrylate ultraviolet absorbers. A UV absorber is preferred.

  Examples of the benzotriazole ultraviolet absorber include 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy- 3,5-dicumylphenyl) phenylbenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2,2'-methylenebis [4- (1,1 , 3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol], 2- (2-hydroxy-3,5-di-tert-butylphenyl) benzotriazole, 2- ( 2-hydroxy-3,5-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy 3,5-di-tert-amylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-butylphenyl) benzotriazole 2- (2-hydroxy-4-octoxyphenyl) benzotriazole, 2,2′-methylenebis (4-cumyl-6-benzotriazolephenyl), 2,2′-p-phenylenebis (1,3- Benzoxazin-4-one), 2- [2-hydroxy-3- (3,4,5,6-tetrahydrophthalimidomethyl) -5-methylphenyl] benzotriazole, and these may be used alone or in combination of two or more. Can be used in a mixture.

  Preferably, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy-3,5-dicumyl) Phenyl) phenylbenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2,2′-methylenebis [4- (1,1,3,3-tetra Methylbutyl) -6- (2H-benzotriazol-2-yl) phenol], 2- [2-hydroxy-3- (3,4,5,6-tetrahydrophthalimidomethyl) -5-methylphenyl] benzotriazole And more preferably 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2,2 ′ Methylenebis [4- (1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl) phenol].

  Examples of benzophenone-based ultraviolet absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, 2-hydroxy-4- Methoxy-5-sulfoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxytrihydridolate benzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5-sodiumsulfoxybenzophenone, bis (5-benzoyl-4-hydroxy-2- Methoxyphenyl) meta , 2-hydroxy -4-n-dodecyloxy benzoin phenone, 2-hydroxy-4-methoxy-2'-carboxy benzophenone.

  Examples of the triazine ultraviolet absorber include 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5-[(hexyl) oxy] -phenol, 2- (4,6-bis ( 2,4-dimethylphenyl) -1,3,5-triazin-2-yl) -5-[(octyl) oxy] -phenol and the like.

  Examples of cyclic imino ester UV absorbers include 2,2′-bis (3,1-benzoxazin-4-one) and 2,2′-p-phenylenebis (3,1-benzoxazin-4-one). 2,2′-m-phenylenebis (3,1-benzoxazin-4-one), 2,2 ′-(4,4′-diphenylene) bis (3,1-benzoxazin-4-one), 2,2 ′-(2,6-naphthalene) bis (3,1-benzoxazin-4-one), 2,2 ′-(1,5-naphthalene) bis (3,1-benzoxazin-4-one) ), 2,2 ′-(2-methyl-p-phenylene) bis (3,1-benzoxazin-4-one), 2,2 ′-(2-nitro-p-phenylene) bis (3,1- Benzoxazin-4-one) and 2,2 ′-(2-chloro-p-ph) Ylene) bis (3,1-benzoxazin-4-one) is illustrated. Among them, 2,2′-p-phenylenebis (3,1-benzoxazin-4-one), 2,2 ′-(4,4′-diphenylene) bis (3,1-benzoxazin-4-one) And 2,2 ′-(2,6-naphthalene) bis (3,1-benzoxazin-4-one) are preferred, especially 2,2′-p-phenylenebis (3,1-benzoxazine-4 -On) is preferred. Such a compound is commercially available from Takemoto Yushi Co., Ltd. as CEi-P (trade name) and can be easily used.

  As the cyanoacrylate ultraviolet absorber, 1,3-bis-[(2′-cyano-3 ′, 3′-diphenylacryloyl) oxy] -2,2-bis [(2-cyano-3,3-diphenyl) Examples include acryloyl) oxy] methyl) propane and 1,3-bis-[(2-cyano-3,3-diphenylacryloyl) oxy] benzene.

  The blending amount of the ultraviolet absorber is preferably 0.01 part by weight to 3.0 parts by weight, more preferably 0.02 part by weight to 1.0 part by weight with respect to 100 parts by weight of the polycarbonate resin. Preferably it is 0.05 weight part-0.8 weight part. If it is the range of this compounding quantity, it is possible to provide sufficient weather resistance to a polycarbonate resin molded product according to a use.

Examples of the bluing agent include Macrolex Violet B, Macrolex Blue RR from Bayer, and Polysynthremble-RLS from Clariant.
The bluing agent is effective for eliminating the yellow color of the polycarbonate resin. In particular, in the case of a polycarbonate resin composition imparted with weather resistance, since a certain amount of ultraviolet absorber is blended, there is a reality that the polycarbonate resin composition tends to be yellowish depending on the action and color of the ultraviolet absorber, especially In order to give a natural transparency to a sheet or lens, the formulation of a bluing agent is very effective.

  The blending amount of the bluing agent is preferably 0.05 to 1.5 ppm, more preferably 0.1 to 1.2 ppm with respect to the polycarbonate resin.

  In the additive supply unit 13, as shown in FIG. 1, the above additives and the like may be supplied to the kneading and extruding apparatus 11 through the side feeder 17. That is, using the side feeder 17 composed of an extruder or the like, solid additives such as the additives, solid additives such as recovered polycarbonate resin and polycarbonate resin composition, etc. B, the additives, etc. Mixing and kneading liquid additives such as liquid additives, catalyst deactivators, and the like C, and supplying them quantitatively to the kneading and extruding device 11 facilitates kneading in the kneading and extruding device 11.

It is preferable that the inner surface of the transfer pipe for the solid additive B supplied to the side feeder 17 is buffed with a mirror finish. By applying this processing finish, there is a possibility that the solid additive B at the time of transfer can be prevented from being blocked in the pipe, causing uneven supply, or causing uneven quality of the obtained polycarbonate resin composition. Is preferable.
Furthermore, the installation angle of the transfer pipe, that is, the transfer angle to the hopper of the side feeder 17 is preferably within ± 20 °, more preferably within ± 10 °, and even more preferably with respect to the vertical direction. ± 0 ° (vertical). When the installation angle (verticality) is larger than ± 20 °, there may be a problem that the solid additive or the like B is blocked in the pipe during transfer.

  In the kneading part 14, the molten polycarbonate resin and additives are kneaded. When the kneading part 14 has at least a forward feed kneading screw and a reverse feed kneading screw, the kneading is performed more reliably. Is preferable.

  Moreover, it is preferable that the said reverse feed kneading screw is 1.0D or more, and it is more preferable that it is 1.5D or more. If it is less than 1.0 D, the mixing and dispersion of the polycarbonate resin and various additives may be insufficient, resulting in a problem of uneven quality. On the other hand, the upper limit is preferably 3.0D, and more preferably 2.5D. If it is larger than 3.0D, the shear during kneading becomes too strong and the color tone of the resin may deteriorate over time. “D” represents the cylinder inner diameter, and “1.0D” represents 1.0 times the cylinder inner diameter (D).

  Since the temperature and pressure of the kneading and extruding device 11 have ranges described later, the component D that is gasified under this condition is removed from the system in the vent portion 15.

  The stabilizer 16 has an effect of constantly and stably extruding the kneaded polycarbonate resin composition, stabilizing the resin filling rate in the kneading and extruding apparatus, and preventing vent-up and the like.

  The polycarbonate resin composition kneaded by the kneading and extruding apparatus is sent to the pelletizing step of the next step to be pelletized and commercialized.

(Each condition in the kneading process)
The specific energy (Esp) required for kneading per unit mass of the polycarbonate resin composition in the kneading extruder is 0.03 kWh / kg or more, preferably 0.04 kWh / kg or more. If it is less than 0.03 kWh / kg, kneading may be insufficient. On the other hand, the upper limit of the specific energy required for kneading is 0.08 kWh / kg, preferably 0.07 kWh / kg. If it is larger than 0.08 kWh / kg, the shear of the screw of the kneading and extruding apparatus becomes too strong, the resin temperature rises, and the color tone may be deteriorated.
The specific energy required for kneading per unit mass of the polycarbonate resin composition refers to the value expressed per unit extrusion mass of the work performed on the raw material by the kneading extrusion device, taking into account the motor efficiency and mechanical efficiency. The amount of electric power consumed by the extruder motor can be obtained by dividing by the extrusion mass, that is, the mass of the resin extruded per unit time.

  Further, the ratio (L / D) of the screw length (L) to the cylinder inner diameter (D) of the kneading extruder is preferably 30 or less, more preferably 25 or less, and still more preferably 20 or less. If it is greater than 30, the resin temperature rises in the kneading and extrusion apparatus, causing residence heat deterioration, and the quality (color tone) may deteriorate over time. On the other hand, the lower limit of L / D is preferably 10, and more preferably 14. If it is less than 10, kneading may be insufficient.

  By the way, as a method of adjusting the specific energy (Esp) within the above range, a method of adjusting the polycarbonate resin temperature (extruder inlet), and a viscosity average molecular weight (Mv) of the polycarbonate resin at the extruder inlet are adjusted. Method, method of adjusting the L / D of the extruder, method of adjusting the configuration of the screw configuration (especially kneading, kneading part), method of adjusting the length of the kneading part, screw rotation speed N and extrusion amount Q There are methods for adjustment, etc., and by optimizing them in combination, Esp can be controlled within a specific range, quality (good color tone) and stable (color blur over time is small) ) A polycarbonate resin composition product can be obtained.

  Regarding the adjustment of the polycarbonate resin temperature (extruder inlet), if this temperature is too low, the dispersion tends to be insufficient (the resin viscosity is too high and cannot be well dispersed with the low viscosity additive, etc.). Although it is necessary to increase Esp, the extruder motor tends to be excessive. On the other hand, if this temperature is too high, Esp can be suppressed, but the color tone tends to deteriorate. The temperature satisfying this purpose is preferably 270 ° C. or higher, and preferably 280 ° C. or higher. On the other hand, the upper limit of this temperature is preferably 310 ° C, and preferably 290 ° C.

  Next, regarding the adjustment of the viscosity average molecular weight (Mv) of the polycarbonate resin at the extruder inlet, when Mv is too large, dispersion tends to be insufficient (resin viscosity is too high, and dispersion with a low viscosity additive is successful. However, it is necessary to increase Esp, but the extruder motor tends to be excessive. On the other hand, Mv may be too low, but the target polycarbonate resin composition may not be obtained in some cases.

  The viscosity average molecular weight (Mv) of the polycarbonate resin that satisfies this purpose is preferably 20,000 or more, and preferably 20,500 or more. On the other hand, the upper limit of Mv is preferably 24,000, and preferably 23,500.

  Next, regarding the adjustment of the L / D of the extruder, if this value is too small, Esp is low, and there is a possibility that poor dispersion and quality fluctuation may occur. On the other hand, if this value is too large, there is a risk of poor color tone due to increased shear heat generation. The range of L / D is as described above.

  Next, regarding the adjustment of the screw configuration, particularly the kneading and the configuration of the kneading section, the screw that has the most influence on the kneading is the reverse feed kneading screw. It is effective to combine a screw for forward feed kneading and reverse feed kneading. If this screw zone is not present or is too short, Esp does not increase, and there is a risk of quality fluctuation due to poor dispersion. On the other hand, if it is too long, the color tone may deteriorate. The length of the screw for the forward feed kneading and the reverse feed kneading, particularly the range of the length of the reverse feed kneading, is as described above.

  Next, the adjustment of the length of the kneading part is performed by adjusting the length of the reverse feed kneading. If this length is too short, Esp does not increase, and there is a risk of quality fluctuation due to poor dispersion. On the other hand, if it is too long, the color tone may deteriorate.

  Next, the screw rotation speed N and the extrusion amount Q are adjusted for the following reason. This is because if the rotational speed N is too small, Esp is small, the dispersion is insufficient, and there is a risk of venting up. On the other hand, if the rotational speed N is too large, the dispersibility is good. (Quality blur is stable), but the color itself tends to deteriorate.

  On the other hand, if the extrusion amount Q is too small, Esp becomes too large, the residence time increases, the thermal deterioration proceeds, and the color tone tends to deteriorate. On the other hand, if the extrusion amount Q is too large, the kneading becomes insufficient, and if it is severe, there is a risk of venting up.

  Furthermore, it is preferable to adjust these ratios Q / N. When Q / N is too low, Esp increases, the temperature of the polycarbonate resin increases, and the color tone may deteriorate. On the other hand, if Q / N is too high, kneading is insufficient, and if it is severe, there is a risk of venting up. Specifically, it is preferable to select this Q / N appropriately according to the capability of the kneading and extruding apparatus.

  The temperature of the molten polycarbonate resin in the kneading extruder is preferably 270 ° C. or higher, and more preferably 280 ° C. or higher. Since the melting point of the polycarbonate resin is around 250 ° C., if it is lower than 270 ° C., it may be necessary to increase the size of the extruder motor due to crystallization of the polycarbonate resin or increase in viscosity, and the problem of poor dispersion with additives. May cause dots. In addition, it is often difficult to knead a molten polycarbonate resin, which has a high viscosity when the temperature is low, with an additive having a low viscosity, if the viscosity difference between them is too large. On the other hand, the upper limit of the resin temperature supplied to the apparatus is preferably 310 ° C, and more preferably 290 ° C. When it is higher than 310 ° C., there may be a problem that the color tone of the resin deteriorates or burns.

  The temperature of the molten polycarbonate resin composition obtained by kneading with the kneading extruder is preferably 350 ° C. or lower, more preferably 330 ° C. or lower, and further preferably 310 ° C. or lower. When the temperature is higher than 350 ° C., there is a case where a problem of deterioration in color tone occurs. On the other hand, the lower limit of the temperature is preferably 280 ° C, and more preferably 290 ° C. When the temperature is lower than 280 ° C., the specific energy required for kneading is small, which may cause a problem of quality fluctuations due to poor dispersion of additives.

  The pressure in the kneading extruder is 4 kPa-Abs. To normal pressure, 20 kPa-Abs. ~ 80 kPa-Abs. Is more preferable. If it is larger than this range, devolatilization tends to be difficult. On the other hand, it may be smaller than this range, but the lower limit of this range is sufficient because of problems on the apparatus.

Hereinafter, the present invention will be described using experimental examples.
First, measurement methods for each evaluation will be described.

<Evaluation method>
(Measurement of Esp)
Measure the motor output P (kW) of the kneading extruder and multiply the motor efficiency by 0.9 to calculate the power consumption of the extruder motor. The power consumption is expressed as the extrusion rate Q (kg / h) of the polycarbonate resin. It was calculated by dividing.
Esp = (P × 0.9) / Q

(Measurement of viscosity average molecular weight (Mv))
Using a methylene chloride solution having a polycarbonate resin concentration (C) of 0.6 g / dl, a specific viscosity (ηsp) measured at a temperature of 20 ° C. with an Ubbelohde viscometer, using both of the following equations, a viscosity average molecular weight: (Mv) was calculated.
ηsp / C = [η] (1 + 0.28 ηsp)
[Η] = 1.23 × 10 ⁻⁴ (Mv) ^0.83

(Measurement of color tone (initial YI value, ΔYI))
[Sample plate forming]
The polycarbonate resin composition pellets obtained in the examples were plasticized at 360 ° C. using an injection molding machine (Nihon Steel Co., Ltd., product name: JSW J75EII) and then retained in a cylinder for 180 seconds to obtain a thickness of 3. Sample plates of 2 mm and 60 mm square were formed. In this molding, the YI values of the first and tenth shot sample plates were measured, and the difference (ΔYI) was taken as a measure of thermal stability.

[Measurement of color tone]
About the said sample board, the color tone (YI value) was measured using the color difference meter (Konica Minolta Sensing Co., Ltd. product name CM-3700D). Of the measured values, the YI value for the first shot is small, indicating that the color tone during steady molding is good, and the difference in the YI value between the first shot and the tenth shot (ΔYI) is small. It shows that the thermal stability is good.

[DPC production example]
While continuously supplying molten commercial phenol and pyridine catalyst to the reactor, phosgene gas was continuously supplied under mixing at 150 ° C. The hydrogen chloride gas produced as a by-product in the phosgenation reaction was cooled to 10 ° C., the condensate was returned to the reactor, and the uncondensed gas was discharged after neutralization with an alkaline aqueous solution. On the other hand, a reaction solution containing about 91% by weight of DPC was continuously extracted from the reactor. The reaction rate of phosgene in the reaction step was almost 100%.

  Next, the reaction solution and about 5% by weight of sodium hydroxide aqueous solution were respectively supplied to a neutralization mixing tank made of Teflon lining, mixed at about 80 ° C. for about 10 minutes, and adjusted to pH 8.5. After neutralization, the organic phase after neutralization was transferred to a washing and mixing tank. In the washing and mixing tank, it is washed with warm water corresponding to about 30% by weight with respect to the organic phase, the aqueous phase is separated, and crude DPC (containing 1% by weight of water, 2% by weight of pyridine, 8% by weight of phenol, 89% by weight of DPC) )

  Next, the crude DPC was continuously fed to the middle stage of the low boiling distillation column at about 30 kg / hr. The low-boiling distillation column has an inner diameter of 150 mm, a height of 4.0 m, a reflux device at the top, a raw material supply unit at the center, and a sulzer packing (manufactured by Sumitomo Heavy Industries, Ltd.) packed in the concentration unit and the recovery unit. A continuous distillation column having 8 stages was used. Distillation of water, pyridine, and phenol, which are lower boiling substances than DPC, by distillation under the conditions of a vacuum degree of 20 torr, a heating medium oil temperature of about 220 ° C., a top temperature of 80 ° C. to 100 ° C., a column temperature in the tower of 160 ° C., and a reflux ratio of 1. Left. From the column bottom, DPC (water 10 wt ppm or less, pyridine 1 wt ppm or less, phenol 50 wt ppm) was continuously extracted at about 26 kg / hr.

  Further, this DPC (the bottoms of the low boiling distillation column) was continuously supplied to the high boiling distillation column. The high-boiling distillation column has an inner diameter of 200 mm and a height of 4.0 m, has a reflux device at the top, a raw material supply unit at the center, and is packed with sulzer packing (manufactured by Sumitomo Heavy Industries, Ltd.) in the concentration unit and recovery unit. A continuous distillation column having 8 stages was used. Distillation was carried out under the conditions of a degree of vacuum of 20 torr, a heating medium oil temperature of about 240 ° C., a top temperature of about 180 ° C., and a reflux ratio of 0.5 to obtain purified DPC from the top.

[Production example of polycarbonate resin]
The above purified DPC and commercially available BPA (bisphenol-A) were mixed at a molar ratio of 1.07: 1.00 to obtain a raw material mixture melt at a temperature of 150 ° C. and a pressure of normal pressure to 900 Torr. Then, an aqueous cesium carbonate solution was added so as to be equivalent to 0.6 micromol with respect to 1 mol of BPA, and used for a polycondensation reaction apparatus. As the polycondensation reaction apparatus, an apparatus in which three vertical reactors and one horizontal reactor were connected in series was used. The conditions are: first reactor-second reactor-third reactor-fourth reactor in the order of 220 ° C., 100 Torr-260 ° C., 30 Torr-270 ° C., 1 Torr-285 ° C., 0.7 Torr. The raw material mixture was polycondensed in order to obtain a molten polycarbonate resin (Mv = 21,400).

(Examples 1-5, Comparative Examples 1-5)
As a kneading and extruding device, a twin-screw extruder TEX65 (L / D = 17.5) provided with Nippon Steel Works Co., Ltd .: a biaxial co-rotating side feeder was used. And the installation vertical angle of the transfer pipe | tube of the solid additive to a side feeder was made into 5 degrees or less. The kneading and extruding apparatus has a molten polycarbonate resin supply unit, an additive supply unit, a kneading unit, a vent unit, and a stabilization unit. The kneading unit has a forward kneading screw and a reverse feeding kneading screw, respectively. And the reverse feed kneading screw was 1.0D.

First, the molten polycarbonate resin was supplied to a molten polycarbonate resin supply unit of a kneading extruder. Next, with respect to 100 parts by weight of molten polycarbonate resin, 2.0 parts by weight of polycarbonate resin pellets as solid additives, 0.01 part by weight of ADK STAB 2112 as heat stabilizer, and catalyst deactivation as liquid additives After adding 0.0006 parts by weight of p-toluenesulfonate butyl sulfonate and 0.35 parts by weight of Unistar H-476, which was previously melted as a release agent, to the side feeder and mixing with the side feeder, It supplied to the additive supply part. More specifically, the solid additive is supplied to the upstream side of the hopper of the side feeder, and the liquid additive is dropped to the downstream side of the hopper so as to spread the liquid additive on the solid additive. did. At this time, the molten polycarbonate resin was supplied so that the extrusion amount (kg / hr) of the obtained molten polycarbonate resin composition was the amount shown in Table 1.
At this time, the inlet resin temperature of the kneading extruder was 285 ° C. Moreover, the rotational speed of the screw of the kneading extruder was set to the values shown in Table 1.
As a result, as shown in Table 1, an appropriate specific energy (Esp) could be obtained in the examples.
The obtained molten polycarbonate resin composition was cut into pellets by a cutter, and the pellets obtained under the same conditions were subjected to aging (10 minutes, 13 minutes, 16 minutes, 19 minutes, 22 minutes, 25 minutes, 28 minutes after starting operation). A total of 8 points were collected in a minute, 31 minutes), a sample plate was molded by the above method, and the color tone was measured. Whether the color tone of the pellets with time was stable was arranged with a standard deviation, and this was used as a scale for evaluating whether the kneaded dispersion state with the additive or the like was good.

DESCRIPTION OF SYMBOLS 11 Kneading extrusion apparatus 12 Polycarbonate resin supply part 13 Additive supply part 14 Kneading part 15 Vent part 16 Stabilization part 17 Side feeder A Molten polycarbonate resin B Solid additive etc. C Liquid additive etc. D Gasification component

Claims (9)

A method for producing a polycarbonate resin composition in which a molten polycarbonate resin and an additive are supplied to a kneading extrusion apparatus and kneaded,
The specific energy required for kneading per unit mass of the polycarbonate resin composition of the kneading and extruding apparatus is 0.03 kWh / kg or more and 0.08 kWh / kg or less, and the L / D of the kneading and extruding apparatus is 30 or less. The
The kneading and extruding apparatus has a kneading section, the kneading section has at least a forward feeding kneading screw and a reverse feeding kneading screw, and the reverse feeding kneading screw is 1.0 D or more,
A method for producing a polycarbonate resin composition, wherein the temperature of the polycarbonate resin composition obtained by kneading with the kneading and extruding apparatus is 350 ° C or lower .   2. The polycarbonate resin composition according to claim 1, wherein the molten polycarbonate resin is obtained by a polycondensation reaction between a dihydroxy compound and a carbonic acid diester compound, and is supplied to a kneading and extruding apparatus in a molten state. Manufacturing method. Manufacturing method of the kneading extruder apparatus, supply of the molten polycarbonate resin, supply of additives, base cement unit, and the polycarbonate resin composition according to claim 1 or 2, characterized in that it comprises at least a stabilizer. The method for producing a polycarbonate resin composition according to any one of claims 1 to 3 , wherein the additive is supplied to a kneading extruder through a side feeder. The method for producing a polycarbonate resin composition according to claim 4 , wherein the additive is mixed with the polycarbonate resin or the polycarbonate resin composition by the side feeder, and the mixture is supplied to a kneading extruder. . The method for producing a polycarbonate resin composition according to claim 5 , wherein a liquid additive is further mixed with the mixture. The method for producing a polycarbonate resin composition according to any one of claims 3 to 6 , wherein an inner surface of a transfer pipe of the additive to the side feeder is buffed with a mirror finish. The method for producing a polycarbonate resin composition according to any one of claims 4 to 7 , wherein an installation angle of the transfer pipe to the side feeder with respect to a vertical direction of the additive is within a vertical angle of 20 °. . The method for producing a polycarbonate resin composition according to any one of claims 1 to 8 , wherein the temperature of the molten polycarbonate resin is 270 ° C or higher.

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