CN107709459B

CN107709459B - Polycarbonate resin composition, method for producing same, and molded article

Info

Publication number: CN107709459B
Application number: CN201580081298.6A
Authority: CN
Inventors: 田中智彦; 吴国章; 苏莉莉; 赖文钦
Original assignee: East China University of Science and Technology; Mitsubishi Chemical Corp
Current assignee: East China University of Science and Technology; Mitsubishi Chemical Corp
Priority date: 2015-06-30
Filing date: 2015-06-30
Publication date: 2020-06-19
Anticipated expiration: 2035-06-30
Also published as: WO2017000155A1; CN107709459A

Abstract

The present invention relates to a polycarbonate resin composition, a method for producing the same, and a molded article. The polycarbonate resin composition contains a specific polycarbonate resin (A) and an aromatic polycarbonate resin (B), has excellent transparency, and has a biomass content, heat resistance and mechanical strength in a highly balanced manner.

Description

Polycarbonate resin composition, method for producing same, and molded article

Technical Field

The present invention relates to a polycarbonate resin composition having excellent transparency and a well-balanced biomass content, heat resistance and mechanical strength.

Background

Conventional aromatic polycarbonate resins containing a chemical structure such as bisphenol a can be produced using raw materials derived from petroleum resources, but in recent years, there has been a demand for polycarbonate resins produced from biomass resources such as plants as raw materials because of concerns about depletion of petroleum resources. In addition, there is a concern that global warming due to excessive carbon dioxide emissions may cause climate change and the like, and there is also a demand for the development of polycarbonate resins produced from plant-derived monomers, which are carbon-neutral even when discarded.

Under such circumstances, there has been proposed a method for producing a polycarbonate resin by using Isosorbide (ISB), which is a dihydroxy compound derived from a biomass resource, as a monomer component and subjecting the monomer component to an ester exchange reaction with a carbonic acid diester, while distilling off a monohydroxy compound produced by a side reaction under reduced pressure (see, for example, patent documents 1 to 7).

However, dihydroxy compounds such as ISB have the following problems: compared with bisphenol compounds used in conventional aromatic polycarbonate resins, the polycarbonate resin has low thermal stability, and yellowing of the resin due to thermal decomposition during polycondensation reaction, molding and processing at high temperatures. Although the copolymers of ISB and bisphenol compounds described in patent documents 3 to 6 have a high glass transition temperature, the reactivity of ISB differs from that of bisphenol compounds, and bisphenol compounds are more likely to be terminal groups of the copolymers. In this case, if the polymerization reaction is carried out at a temperature lower than the polymerization temperature of the aromatic polycarbonate resin in consideration of color tone and thermal stability of ISB, the bisphenol compound may be a kind of a terminal capping group, and the polymerization degree cannot be sufficiently increased, and the impact toughness of the product may be poor, which is remarkable when the copolymerization amount of the bisphenol compound exceeds 20 mol%.

Further, patent document 7 discloses a polycarbonate copolymer containing an ISB-derived structural unit, an aliphatic dihydroxy compound-derived structural unit, and an aromatic bisphenol compound-derived structural unit, but this polycarbonate copolymer is excellent in heat resistance, moldability, and mechanical strength, but because of the bisphenol compound-derived structural unit, the degree of polymerization is not sufficiently increased, and the polymer may be poor in impact toughness. Further, the biomass content is low, and is not preferable from the viewpoint of environmental protection.

Polycarbonate resins containing dihydroxy compounds such as Isosorbide (ISB) which is a biomass-derived dihydroxy compound have high glass transition temperatures and excellent heat resistance, but have the following disadvantages: in addition to molecular chain stiffness, the viscosity at the time of melt polymerization is high, and a high molecular weight product cannot be obtained, and therefore, impact toughness is poor. In order to improve toughness, it has been attempted to copolymerize an aliphatic dihydroxy compound or an aromatic bisphenol compound.

Specifically, patent document 8 discloses a polycarbonate resin composition comprising a polycarbonate comprising two structural units of ISB and a dihydroxy compound derived from an aliphatic hydrocarbon and an aromatic polycarbonate resin, wherein the content of the dihydroxy compound structural unit derived from an aliphatic hydrocarbon in the former polycarbonate is 45 mol% or more. Further, patent document 9 discloses a polycarbonate resin composition having excellent pencil hardness, which is obtained by mixing an aromatic polycarbonate resin with a polycarbonate resin containing ISB and a dihydroxy compound structural unit of an aliphatic hydrocarbon.

Documents of the prior art

Patent document

Patent document 1: international publication No. 2004/111106 pamphlet

Patent document 2: international publication No. 2007/063823 pamphlet

Patent document 3: international publication No. 2005/066239 pamphlet

Patent document 4: international publication No. 2006/041190 pamphlet

Patent document 5: japanese laid-open patent publication No. 2009-062501

Patent document 6: japanese laid-open patent publication No. 2009-020963

Patent document 7: japanese patent laid-open publication No. 2011-

Patent document 8: international publication No. 2011/071162 pamphlet

Patent document 9: international publication No. 2012/1117212 pamphlet

Disclosure of Invention

Problems to be solved by the invention

However, there are the following problems: the aliphatic dihydroxy compound-containing copolymer has insufficient heat resistance, and the aromatic bisphenol compound-containing copolymer has high heat resistance, but a polycarbonate resin having a sufficient molecular weight cannot be obtained from the viewpoint of reactivity. Therefore, as described in patent document 8, a resin composition of an ISB copolymerized polycarbonate resin containing an aliphatic dihydroxy compound in an amount of 45 mol% or more and an aromatic polycarbonate resin is excellent in transparency, hue, thermal stability, moldability and mechanical strength, but if the glass transition temperature of the composition is increased to 120 ℃ or more in order to further improve heat resistance, it is necessary to increase the content of the aromatic polycarbonate resin to 50% by weight or more. This inevitably lowers the biomass content, and is therefore not preferable from the environmental viewpoint. Further, as described in patent document 9, a polycarbonate resin containing two structural units of ISB and a dihydroxy compound of an aliphatic hydrocarbon is mixed with an aromatic polycarbonate resin, and this polycarbonate resin composition has a problem that the total light transmittance is substantially less than 20% and the transparency is poor.

The present invention has been made in view of such a background, and provides a polycarbonate resin composition which is excellent in transparency and has a biomass content, heat resistance and mechanical strength in a well-balanced manner at a high level, a method for producing the same, and a molded article of the polycarbonate resin composition.

Means for solving the problems

The present inventors have conducted intensive studies to solve the above problems, and as a result, have found that a polycarbonate resin composition containing a specific polycarbonate resin (a) and an aromatic polycarbonate resin (B) has excellent transparency and has a biomass content, heat resistance and mechanical strength in a highly balanced manner, and have completed the present invention. The gist of the present invention is the following [1] to [4 ].

[1] A polycarbonate resin composition comprising a polycarbonate resin (A) containing a structural unit derived from a compound represented by the following formula (1), an aromatic polycarbonate resin (B), and at least one compound (C) selected from a tin compound represented by the following formula (2) or (3) and a basic nitrogen-containing compound, wherein the amount of the compound (C) added is 0.001 to 5 parts by weight based on 100 parts by weight of a resin composition comprising the polycarbonate resin (A) and the aromatic polycarbonate resin (B).

[ chemical formula 1]

[ chemical formula 2]

[ chemical formula 2]

(wherein R represents an alkyl group or an aryl group having 1 to 15 carbon atoms, and X1 to X4 represent 1-valent groups each containing an alkyl group having 1 to 15 carbon atoms, an aryl group, an allyloxy group, a cyclohexyl group, a hydroxyl group, a halogen atom or the like, and may be the same or different; and X5 represents a sulfur or oxygen atom.)

[2] The polycarbonate resin composition according to [1], wherein the polycarbonate resin composition has only one glass transition temperature as measured by differential scanning calorimetry.

[3] The polycarbonate resin composition according to [1] or [2], wherein the polycarbonate resin composition has a total light transmittance of 80% or more in a molded article having a thickness of 1 mm.

[4] The polycarbonate resin composition according to [2] or [3], wherein the polycarbonate resin composition has a glass transition temperature of 90 ℃ or more and 200 ℃ or less as measured by differential scanning calorimetry.

Effects of the invention

The polycarbonate resin composition and the molded article thereof of the present invention have excellent transparency and have a highly balanced combination of biomass content, heat resistance and mechanical strength. The polycarbonate resin composition of the present invention is obtained by the above-mentioned components through the addition step and the reaction step.

Detailed Description

The embodiments of the present invention will be described in detail below, but the description of the constituent elements described below is an example (representative example) of the embodiments of the present invention, and the present invention is not limited to the following as long as the invention does not exceed the gist thereof.

[ polycarbonate resin (A) ]

The polycarbonate resin (a) is preferably a polycarbonate resin containing a structural unit derived from a dihydroxy compound represented by the following formula (1) (simply referred to as "structural unit (a)") in a proportion exceeding 50 mol% relative to 100 mol% of structural units derived from all dihydroxy compounds. The polycarbonate resin (a) may be a homopolycarbonate resin having the structural unit (a), or a polycarbonate resin obtained by copolymerizing structural units other than the structural unit (a). From the viewpoint of optimizing impact toughness, a copolymerized polycarbonate resin is preferable.

[ chemical formula 5]

Examples of the dihydroxy compound represented by the formula (1) include: isosorbide (ISB), isomannide, and isoidide in a stereoisomeric relationship. These dihydroxy compounds may be used alone in1 kind, or may be used in combination in 2 or more kinds.

Among the dihydroxy compounds represented by the above general formula (1), Isosorbide (ISB) obtained by dehydration condensation of sorbitol which is abundant in plant sources and is easily converted from various starches is most preferable from the viewpoints of easiness of obtaining and producing, weather resistance, optical properties, moldability, heat resistance and carbon neutrality.

The dihydroxy compound represented by the above general formula (1) is easily and slowly oxidized by oxygen. Therefore, in order to prevent oxidative decomposition during storage or use, it is preferable to use a deoxidizer or under a nitrogen atmosphere without mixing water.

The polycarbonate resin (a) is preferably a copolymerized polycarbonate resin containing a structural unit (a) derived from a dihydroxy compound represented by general formula (1) and a structural unit (simply referred to as "structural unit (b)") selected from 1 or more kinds of dihydroxy compounds selected from a dihydroxy compound of an aliphatic hydrocarbon, a dihydroxy compound of an alicyclic hydrocarbon, or a dihydroxy compound containing an ether bond. Since these dihydroxy compounds have a flexible molecular structure, the impact toughness of the polycarbonate resin can be improved by using these dihydroxy compounds as raw materials. Among these dihydroxy compounds, aliphatic hydrocarbon dihydroxy compounds and alicyclic hydrocarbon dihydroxy compounds having a large effect of improving toughness are preferably used, and alicyclic hydrocarbon dihydroxy compounds are most preferably used. Specific examples of the dihydroxy compound of an aliphatic hydrocarbon, the dihydroxy compound of an alicyclic hydrocarbon, and the dihydroxy compound containing an ether bond are as follows.

The dihydroxy compounds selected from the group consisting of aliphatic hydrocarbons include: linear aliphatic dihydroxy compounds such as ethylene glycol, 1, 3-propanediol, 1, 2-propanediol, 1, 4-butanediol, 1, 5-heptanediol, 1, 6-hexanediol, 1, 9-nonanediol, 1, 10-decanediol, 1, 12-dodecanediol, and the like; and branched aliphatic dihydroxy compounds such as 1, 3-butanediol, 1, 2-butanediol, neopentyl glycol and hexanediol.

Dihydroxy compounds selected from alicyclic hydrocarbons include: dihydroxy compounds exemplified as primary alcohols of alicyclic hydrocarbons such as 1, 2-cyclohexanedimethanol, 1, 3-cyclohexanedimethanol, 1, 4-cyclohexanedimethanol, tricyclodecanedimethanol, pentacyclopentadecane dimethanol, 2, 6-decalin dimethanol, 1, 5-decalin dimethanol, 2, 3-norbornane dimethanol, 2, 5-norbornane dimethanol, 1, 3-adamantane dimethanol, and dihydroxy compounds derived from terpene compounds such as limonene; dihydroxy compounds of secondary alcohols or tertiary alcohols exemplified as 1, 2-cyclohexanediol, 1, 4-cyclohexanediol, 1, 3-adamantanediol, hydrogenated bisphenol a, 2,4, 4-tetramethyl-1, 3-cyclobutanediol, and the like.

Examples of the dihydroxy compound having an ether bond include: oxyalkylene glycols or dihydroxy compounds containing an acetal ring.

Examples of the oxyalkylene glycol include diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, and polypropylene glycol.

As the dihydroxy compound having an acetal ring, for example, a spirodiol represented by the following structural formula (5), a dioxan diol represented by the following structural formula (6), or the like can be used.

[ chemical formula 6]

[ chemical formula 7]

In the polycarbonate resin (a), the content ratio of the structural unit (a) to 100 mol% of the structural units derived from all dihydroxy compounds is preferably more than 50 mol%, more preferably 55 mol% or more and 95 mol% or less, still more preferably 60 mol% or more and 90 mol% or less, and particularly preferably 65 mol% or more and 85 mol% or less. When the content ratio of the structural unit (a) is 50 mol% or less, the biomass content is low and the heat resistance is insufficient. On the other hand, the structural unit (a) may be 100 mol%, but copolymerization is preferably carried out from the viewpoint of improvement of molecular weight and impact resistance.

The polycarbonate resin (a) may further contain a structural unit other than the structural unit (a) and the structural unit (b). As such a structural unit (dihydroxy compound), for example, a dihydroxy compound having an aromatic group or the like can be used. However, when the polycarbonate resin (a) contains a structural unit derived from an aromatic dihydroxy compound, a high molecular weight polycarbonate resin may not be obtained for the above reasons, and impact toughness may be poor. Therefore, the content ratio of the structural unit derived from the aromatic group-containing dihydroxy compound is preferably 10 mol% or less, and more preferably 5 mol% or less, based on 100 mol% of the structural units derived from all dihydroxy compounds.

As the aromatic group-containing dihydroxy compound, for example, the following dihydroxy compounds can be used, but dihydroxy compounds other than these can also be used. 2, 2-bis (4-hydroxyphenyl) propane, 2-bis (3-methyl-4-hydroxyphenyl) propane, 2-bis (4-hydroxy-3, 5-dimethylphenyl) propane, 2-bis (4-hydroxy-3, 5-diethylphenyl) propane, 2-bis (4-hydroxy- (3-phenyl) propane, 2-bis (4-hydroxy- (3, 5-diphenyl) phenyl) propane, 2-bis (4-hydroxy-3, 5-dibromophenyl) propane, bis (4-hydroxyphenyl) methane, 1-bis (4-hydroxyphenyl) ethane, 2-bis (4-hydroxyphenyl) butane, 2, 2-bis (4-hydroxyphenyl) pentane, 1-bis (4-hydroxyphenyl) -1-phenylethane, bis (4-hydroxyphenyl) diphenylmethane, 1-bis (4-hydroxyphenyl) -2-ethylhexane, 1-bis (4-hydroxyphenyl) decane, bis (4-hydroxy-3-nitrophenyl) methane, 3-bis (4-hydroxyphenyl) pentane, 1, 3-bis (2- (4-hydroxyphenyl) -2-propyl) benzene, 2-bis (4-hydroxyphenyl) hexafluoropropane, 1-bis (4-hydroxyphenyl) cyclohexane, Aromatic bisphenol compounds such as bis (4-hydroxyphenyl) sulfone, 2,4 '-dihydroxydiphenyl sulfone, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxy-3-methylphenyl) sulfide, bis (4-hydroxyphenyl) disulfide, 4' -dihydroxydiphenyl ether, and 4,4 '-dihydroxy-3, 3' -dichlorodiphenyl ether; dihydroxy compounds having an ether group bonded to an aromatic group, such as2, 2-bis (4- (2-hydroxyethoxy) phenyl) propane, 2-bis (4- (2-hydroxypropoxy) phenyl) propane, 1, 3-bis (2-hydroxyethoxy) benzene, 4' -bis (2-hydroxyethoxy) biphenyl, and bis (4- (2-hydroxyethoxy) phenyl) sulfone; 9, 9-bis (4- (2-hydroxyethoxy) phenyl) fluorene, 9-bis (4-hydroxyphenyl) fluorene, 9-bis (4-hydroxy-3-methylphenyl) fluorene, 9-bis (4- (2-hydroxypropoxy) phenyl) fluorene, 9-bis (4- (2-hydroxyethoxy) -3-methylphenyl) fluorene, 9-bis (4- (2-hydroxypropoxy) -3-methylphenyl) fluorene, 9-bis (4- (2-hydroxyethoxy) -3-isopropylphenyl) fluorene, 9-bis (4- (2-hydroxyethoxy) -3-isobutylphenyl) fluorene, 9-bis (4- (2-hydroxyethoxy) -3-t-butylphenyl) fluorene Dihydroxy compounds having a fluorene ring such as fluorene, 9-bis (4- (2-hydroxyethoxy) -3-cyclohexylphenyl) fluorene, 9-bis (4- (2-hydroxyethoxy) -3-phenylphenyl) fluorene, 9-bis (4- (2-hydroxyethoxy) -3, 5-dimethylphenyl) fluorene, 9-bis (4- (2-hydroxyethoxy) -3-tert-butyl-6-methylphenyl) fluorene, and 9, 9-bis (4- (3-hydroxy-2, 2-dimethylpropoxy) phenyl) fluorene.

The other dihydroxy compound may be appropriately selected depending on the properties required for the polycarbonate resin. The other dihydroxy compounds may be used alone in1 kind or in combination of two or more kinds. By using the above-mentioned other dihydroxy compound in combination with the dihydroxy compound represented by formula (1), the polycarbonate resin (a) can be improved in flexibility and mechanical properties, and can be improved in moldability.

The dihydroxy compound used as a raw material of the polycarbonate resin (A) may contain a reducing agent, an antioxidant, a deoxidizer, a light stabilizer, an antacid, a pH stabilizer, a heat stabilizer, and other stabilizers. In particular, since the dihydroxy compound represented by the above formula (1) has a property of being easily deteriorated in an acidic state, the deterioration of the dihydroxy compound represented by the above formula (1) can be suppressed by using an alkaline stabilizer in the synthesis process of the polycarbonate resin (a), and the quality of the obtained polycarbonate resin composition can be further improved.

As the basic stabilizer, for example, the following compounds can be used. Hydroxides, carbonates, phosphates, phosphites, hypophosphites, borates and fatty acid salts of metals of group IA or IIA of the long-period periodic Table (Nomenstratureof organic Chemistry IUPAC Recommendations 2005); basic ammonium compounds such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, trimethylbenzylammonium hydroxide, trimethylphenylammonium hydroxide, triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, methyltriphenylammonium hydroxide and butyltriphenylammonium hydroxide; amine compounds such as diethylamine, dibutylamine, triethylamine, morpholine, N-methylmorpholine, pyrrolidine, piperidine, 3-amino-1-propanol, ethylenediamine, N-methyldiethanolamine, diethylethanolamine, diethanolamine, triethanolamine, 4-aminopyridine, 2-aminopyridine, N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 2-dimethylaminoimidazole, 2-methoxyimidazole, imidazole, 2-mercaptoimidazole, 2-methylimidazole and aminoquinoline, and hindered amine compounds such as di (tert-butyl) amine and 2,2,6, 6-tetramethylpiperidine.

The content of the basic stabilizer in the dihydroxy compound is not particularly limited, and since the dihydroxy compound represented by formula (1) is unstable in an acidic state, the content of the basic stabilizer is preferably set so that the pH of an aqueous solution of the dihydroxy compound containing the basic stabilizer is about 7.

If the amount of the basic stabilizer is too small, the effect of preventing the dihydroxy compound represented by formula (1) from being deteriorated may not be obtained. On the other hand, if the amount of the basic stabilizer is too large, the dihydroxy compound may be modified by the basic stabilizer. In order to avoid such a problem, the content of the basic stabilizer is preferably 0.0001 to 1% by mass, more preferably 0.001 to 0.1% by mass, based on the dihydroxy compound represented by the formula (1).

As the carbonic acid diester used as a raw material for the polycarbonate resin [ A ], a compound represented by the following general formula (9) can be usually used. These carbonic acid diesters may be used alone in1 kind, or may be used in combination in 2 or more kinds.

[ chemical formula 8]

In the above general formula (9), A¹And A²Respectively is a substituted or unsubstituted aliphatic hydrocarbon group or a substituted or unsubstituted aromatic hydrocarbon group having 1 to 18 carbon atoms, A¹And A²May be the same or different. As A¹And A²Preferably, a substituted or unsubstituted aromatic hydrocarbon group is used, and more preferably, an unsubstituted aromatic hydrocarbon group is used.

Examples of the carbonic acid diester represented by the above general formula (9) include substituted diphenyl carbonates such as diphenyl carbonate (DPC) and ditolyl carbonate, dimethyl carbonate, diethyl carbonate, and di-t-butyl carbonate. Of these carbonic acid diesters, diphenyl carbonate or substituted diphenyl carbonate is preferably used, and diphenyl carbonate is particularly preferably used. Further, since the carbonic acid diester may contain impurities such as chloride ions and the impurities may inhibit the polycondensation reaction or deteriorate the color tone of the obtained polycarbonate resin, it is preferable to use a carbonic acid diester purified by distillation or the like as necessary.

The polycarbonate resin (a) can be synthesized by polycondensing the above dihydroxy compound and carbonic acid diester by an ester exchange reaction. More specifically, the polyester resin can be obtained by removing a monohydroxy compound and the like produced as a side reaction in the transesterification reaction out of the system simultaneously with the polycondensation.

The above-mentioned transesterification reaction is carried out in the presence of a transesterification catalyst (hereinafter, the transesterification catalyst is referred to as "polymerization catalyst"). The kind of the polymerization catalyst may greatly affect the reaction rate of the transesterification reaction and the quality of the obtained polycarbonate resin (A).

The polymerization catalyst is not limited as long as it satisfies the transparency, color tone, heat resistance, weather resistance and mechanical strength of the obtained polycarbonate resin (A). As the polymerization catalyst, for example, a metal compound of group IA or group IIA (hereinafter, referred to as "group IA" or "group IIA") in the long-period periodic table, and a basic compound such as a basic boron compound, a basic phosphorus compound, a basic ammonium compound, and an amine compound can be used, and among them, a group IA metal compound and/or a group IIA metal compound is preferable.

As the group IA metal compound, for example, the following compounds can be used. Sodium hydroxide, potassium hydroxide, lithium hydroxide, cesium hydroxide, sodium bicarbonate, potassium bicarbonate, lithium bicarbonate, cesium bicarbonate, sodium carbonate, potassium carbonate, lithium carbonate, cesium carbonate, sodium acetate, potassium acetate, lithium acetate, cesium acetate, sodium stearate, potassium stearate, lithium stearate, cesium stearate, sodium borohydride, potassium borohydride, lithium borohydride, cesium borohydride, sodium borohydride, potassium borohydride, lithium borohydride, potassium benzoate, lithium benzoate, cesium benzoate, disodium hydrogen phosphate, dipotassium hydrogen phosphate, dilithium hydrogen phosphate, dicesium hydrogen phosphate, disodium phenylphosphate, dipotassium phenylphosphate, dilithium phenylphosphate, and dicesium phenylphosphate; alkoxides, phenoxides of sodium, potassium, lithium, cesium; disodium, dipotassium, dilithium, and dicesium salts of bisphenol a, and the like.

As the group IA metal compound, a lithium compound is preferable from the viewpoint of polymerization activity and color tone of the obtained polycarbonate resin.

As the group IIA metal compound, for example, the following compounds can be used. Calcium hydroxide, barium hydroxide, magnesium hydroxide, strontium hydroxide, calcium hydrogen carbonate, barium hydrogen carbonate, magnesium hydrogen carbonate, strontium hydrogen carbonate, calcium carbonate, barium carbonate, magnesium carbonate, strontium carbonate, calcium acetate, barium acetate, magnesium acetate, strontium acetate, calcium stearate, barium stearate, magnesium stearate, strontium stearate, and the like.

The group IIA metal compound is preferably a magnesium compound, a calcium compound, or a barium compound, and from the viewpoint of polymerization activity and color tone of the obtained polycarbonate resin, a magnesium compound and/or a calcium compound is more preferable, and a calcium compound is most preferable.

In addition, a basic compound such as a basic boron compound, a basic phosphorus compound, a basic ammonium compound, and an amine compound may be used together with the above-mentioned group IA metal compound and/or group IIA metal compound, and it is particularly preferable to use only the group IA metal compound and/or group IIA metal compound.

As the basic phosphorus compound, for example, the following compounds can be used. Triethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triphenylphosphine, tributylphosphine, quaternary phosphonium salts, and the like.

As the basic ammonium compound, for example, the following compounds can be used. Tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, trimethylbenzylammonium hydroxide, trimethylphenylammonium hydroxide, triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, methyltriphenylammonium hydroxide, butyltriphenylammonium hydroxide, and the like.

As the amine compound, for example, the following compounds can be used. 4-aminopyridine, 2-aminopyridine, N-dimethyl-4-aminopyridine, 4-diethylaminopyridine, 2-hydroxypyridine, 2-methoxypyridine, 4-methoxypyridine, 2-dimethylaminoimidazole, 2-methoxyimidazole, imidazole, 2-mercaptoimidazole, 2-methylimidazole, aminoquinoline, guanidine, etc.

The amount of the polymerization catalyst used is preferably 0.1 to 300. mu. mol, more preferably 0.5 to 100. mu. mol, and particularly preferably 1 to 50. mu. mol, per 1mol of the total dihydroxy compound used in the reaction.

When a compound containing at least 1 metal selected from the group consisting of group IIA metals and lithium in the long-period periodic Table, particularly a magnesium compound and/or a calcium compound is used as the polymerization catalyst, the amount of the polymerization catalyst to be used is preferably 0.1. mu. mol or more, more preferably 0.3. mu. mol or more, particularly preferably 0.5. mu. mol or more per 1mol of the total dihydroxy compound to be used in the reaction, based on the metal atom amount of the compound containing the metal. The upper limit is preferably 10. mu. mol or less, more preferably 5. mu. mol or less, and particularly preferably 3. mu. mol or less.

If the amount of the polymerization catalyst used is too small, the polymerization rate becomes slow, and therefore, in order to obtain a polycarbonate resin having a desired molecular weight, the polymerization temperature must be increased accordingly. Therefore, there is a possibility that the obtained polycarbonate resin (a) may have a poor color tone, or that unreacted raw materials volatilize during polymerization to destroy the molar ratio of the dihydroxy compound and the carbonic acid diester, and the desired molecular weight may not be achieved. On the other hand, if the amount of the polymerization catalyst used is too large, undesirable side reactions may be caused, which may deteriorate the color tone of the obtained polycarbonate resin (a) or may cause coloration of the resin during molding.

In addition, when a large amount of sodium, potassium or cesium is contained in the polycarbonate resin in the group IA metal, the color tone may be adversely affected. In addition, if a large amount of iron is contained in the polycarbonate resin, there is also a possibility that the color tone is adversely affected. Further, these metals are not only derived from the catalyst used but also mixed in from the raw material or the reaction apparatus. In any case, the total amount of the compounds of these metals in the polycarbonate resin (a) is preferably 1 mass ppm or less, more preferably 0.5 mass ppm or less, in terms of the total content of sodium, potassium, cesium and iron.

(Synthesis of polycarbonate resin (A))

The polycarbonate resin (a) can be obtained by polycondensing a dihydroxy compound used as a raw material such as the dihydroxy compound represented by the above formula (1) and a carbonic acid diester by an ester exchange reaction in the presence of a polymerization catalyst.

The dihydroxy compound and the carbonic acid diester as raw materials are preferably uniformly mixed before the ester exchange reaction. The temperature of the mixing is usually 80 ℃ or more, preferably 90 ℃ or more, and usually 250 ℃ or less, preferably 200 ℃ or less, more preferably 150 ℃ or less, and among them, preferably 100 ℃ or more and 120 ℃ or less. If the mixing temperature is too low, the dissolution rate may be slow or the solubility may be insufficient, and problems such as solidification may be caused. On the other hand, if the mixing temperature is too high, thermal deterioration of the dihydroxy compound may be caused, and as a result, the color tone of the obtained polycarbonate resin (a) may be deteriorated or the weather resistance may be adversely affected.

From the viewpoint of suppressing deterioration of color tone and reduction of reactivity, the operation of mixing the dihydroxy compound and the carbonic acid diester as raw materials is preferably carried out in an atmosphere having an oxygen concentration of 10 vol% or less, further 0.0001 to 10 vol%, particularly 0.0001 to 5 vol%, and particularly 0.0001 to 1 vol%.

In order to obtain the polycarbonate resin (A), the carbonic acid diester is preferably used in a molar ratio of 0.90 to 1.20, more preferably 0.95 to 1.10, based on the total dihydroxy compounds used in the reaction. If the molar ratio is small, the amount of the hydroxyl terminal of the produced polycarbonate resin (a) increases, which may deteriorate the thermal stability of the polymer, cause coloration during molding, decrease the rate of transesterification reaction, or fail to obtain a desired high molecular weight product.

When the molar ratio is increased, the rate of the transesterification reaction may be decreased, or it may be difficult to produce the polycarbonate resin (a) having a desired molecular weight. Since a decrease in the transesterification reaction rate leads to an increase in the progress of the reaction under heat, the color tone and weather resistance of the obtained polycarbonate resin (a) may be deteriorated. Further, when the molar ratio of the carbonic acid diester to the total dihydroxy compounds is increased, the amount of the carbonic acid diester remaining in the polycarbonate resin (a) to be obtained may increase, which is not preferable because it may cause problems of contamination and odor during molding.

The method of polycondensing a dihydroxy compound and a carbonic acid diester is carried out in multiple stages using a plurality of reactors in the presence of the above catalyst. The reaction may be carried out in a batch type or a continuous type, or a combination of a batch type and a continuous type, and it is preferable to use a method capable of obtaining a polycarbonate resin with less heat history, and the production efficiency is also preferable to the continuous type.

From the viewpoint of controlling the polymerization rate and the quality of the obtained polycarbonate resin (a), it is important to appropriately select the jacket temperature, the internal temperature, and the pressure in the reaction system depending on the reaction stage. Specifically, it is preferable that the prepolymer is obtained at a relatively low temperature and a low vacuum in the initial stage of the polycondensation reaction, and the molecular weight is increased to a predetermined value at a relatively high temperature and a high vacuum in the latter stage of the polycondensation reaction. For example, if either one of the temperature and the pressure is changed too rapidly before the progress of the polycondensation reaction reaches a predetermined value, unreacted monomers may be distilled off, and the molar ratio of the dihydroxy compound and the carbonic acid diester may be deviated from a desired ratio. As a result, the polymerization rate may be reduced, or a polymer having a desired molecular weight or terminal group may not be obtained.

In addition, the polymerization rate in the polycondensation reaction is controlled by the balance of the hydroxyl group terminal and the carbonate group terminal. Therefore, if the balance of the terminal groups fluctuates due to the distillation-off of the unreacted monomer, it may be difficult to control the polymerization rate to be constant or the fluctuation in the molecular weight of the obtained resin may become large. Since the molecular weight of the resin is related to the melt viscosity, the melt viscosity may fluctuate during melt processing, and it is difficult to maintain the quality of the molded article. This problem is particularly likely to occur when the polycondensation reaction is carried out continuously.

In order to suppress the amount of unreacted monomer distilled off, it is effective to use a reflux condenser in the polymerization reactor, and particularly, to exhibit a high effect at the initial stage of the reaction when the amount of unreacted monomer is large. The temperature of the refrigerant introduced into the reflux condenser can be suitably selected depending on the monomer used, and is usually 45 to 180 ℃, preferably 80 to 150 ℃, and particularly preferably 100 to 130 ℃ at the inlet of the reflux condenser. If the temperature of the refrigerant is too high, the amount of reflux decreases, and the effect thereof decreases, whereas if the temperature is too low, the efficiency of distillation removal of the monohydroxy compound that should be distilled off may decrease, and the reaction rate may decrease, and the obtained resin may be colored. As the refrigerant, warm water, steam, heat medium oil, or the like can be used, and steam and heat medium oil are preferable.

In order to keep the polymerization rate at an appropriate rate, suppress the distillation-off of the monomer, and prevent the color tone of the obtained polycarbonate resin (A), it is important to select the kind and amount of the above-mentioned polymerization catalyst.

The polycarbonate resin (a) is usually produced through 2 or more stages of steps using a polymerization catalyst. The polycondensation reaction can be carried out in 2 or more stages by using 1 polycondensation reactor and changing the conditions in sequence, but from the viewpoint of production efficiency, it is preferable to carry out the polycondensation reaction in multiple stages by using a plurality of reactors and changing the respective conditions.

From the viewpoint of efficiently carrying out the polycondensation reaction, it is important to suppress the volatilization of the monomer while maintaining a necessary polymerization rate at the initial stage of the reaction in which the amount of the monomer contained in the reaction liquid is large. In addition, it is important to remove the monohydroxy compound produced by the side reaction by sufficient distillation at the latter stage of the reaction so that the equilibrium shifts toward the side of the polycondensation reaction. Therefore, the reaction conditions preferred in the initial stage of the reaction and the reaction conditions preferred in the latter stage of the reaction are usually different. Therefore, by using a plurality of reactors arranged in series, the respective conditions can be easily changed, and the production efficiency can be improved.

The number of polymerization reactors used for producing the polycarbonate resin (a) may be at least 2 as described above, but is 3 or more, preferably 3 to 5, and particularly preferably 4 from the viewpoint of production efficiency. When the number of the polymerization reactors is 2 or more, a plurality of reaction stages having different conditions or a continuous change in temperature and pressure may be further performed in each polymerization reactor.

The polymerization catalyst may be added to the raw material preparation tank or the raw material storage tank, or may be directly added to the polymerization reactor. From the viewpoint of stability of supply and control of the polycondensation reaction, it is preferable to provide a catalyst supply line in the middle of the raw material line before supply to the polymerization reactor and supply the polymerization catalyst as an aqueous solution.

If the temperature of the polycondensation reaction is too low, the productivity is lowered or the heat history applied to the product is increased, and if the temperature is too high, not only the volatilization of the monomer is caused, but also the decomposition or coloring of the polycarbonate resin (a) may be promoted. Specifically, the following conditions can be adopted as the reaction conditions in the 1 st stage reaction. That is, the maximum temperature of the internal temperature of the polymerization reactor is usually set in the range of 150 to 250 ℃, preferably 160 to 240 ℃, and more preferably 170 to 230 ℃. The pressure in the polymerization reactor (hereinafter, the pressure is expressed as an absolute pressure) is usually set in the range of 1 to 110kPa, preferably 5 to 70kPa, and more preferably 7 to 30 kPa. The reaction time is usually set in the range of 0.1 to 10 hours, preferably 0.5 to 3 hours. The reaction in the 1 st stage is carried out while distilling off the produced monohydroxy compound to the outside of the reaction system.

After the 2 nd stage, the pressure of the reaction system is gradually lowered from the pressure in the 1 st stage, and the pressure (absolute pressure) of the final reaction system is set to 1kPa or less while continuously removing the produced monohydroxy compound to the outside of the reaction system. The maximum temperature of the internal temperature of the polymerization reactor is usually set in the range of 200 to 260 ℃ and preferably 210 to 250 ℃. The reaction time is usually set in the range of 0.1 to 10 hours, preferably 0.3 to 6 hours, and particularly preferably 0.5 to 3 hours.

If the polymerization temperature is excessively increased and the polymerization time is prolonged, the color tone of the obtained polycarbonate resin (a) tends to be deteriorated. In particular, in order to obtain a polycarbonate resin (A) having a good color tone by suppressing coloring or thermal deterioration of the polycarbonate resin (A), it is preferable to set the maximum temperature of the internal temperature of the polymerization reactor at 210 to 240 ℃ in all the reaction stages. In order to suppress the decrease in the polymerization rate in the latter half of the reaction, deterioration due to the thermal process is minimized, and it is preferable to use a horizontal reactor having excellent plug flow properties and interface renewal properties in the final stage of the polycondensation reaction.

In the continuous polymerization, in order to control the molecular weight of the finally obtained polycarbonate resin (a) to a certain level, it is necessary to adjust the polymerization rate as necessary. In this case, the pressure of the polymerization reactor in the final stage is adjusted to be a method with good operability.

Further, since the polymerization rate varies depending on the ratio of the hydroxyl group terminal to the carbonate group terminal as described above, it is possible to intentionally decrease one of the terminal groups, to suppress the polymerization rate, and to reduce the residual low-molecular-weight component in the resin represented by the monohydroxy compound by keeping the pressure in the polymerization reactor at the final stage at a high vacuum. However, in this case, if one end is too small, the reactivity may be extremely lowered only by slight fluctuation of the terminal group balance, and the molecular weight of the obtained polycarbonate resin (a) may not satisfy a desired molecular weight. In order to avoid such a problem, it is preferable that the polycarbonate resin (A) obtained in the final polymerization reactor contains 10mol/ton or more of both of the hydroxyl group terminal and the carbonate group terminal. On the other hand, when both end groups are too large, the polymerization rate becomes high and the molecular weight fluctuation becomes too high, and therefore, one end group is preferably 60mol/ton or less.

By adjusting the amount of the terminal group and the pressure of the polymerization reactor in the final stage to the preferred ranges as described above, the amount of the residual monohydroxy compound in the resin can be reduced at the outlet of the polymerization reactor. The residual amount of the monohydroxy compound in the resin at the outlet of the polymerization reactor is preferably 2000 mass ppm or less, more preferably 1500 mass ppm or less, and still more preferably 1000 mass ppm or less. By reducing the content of the monohydroxy compound in the outlet of the polymerization reactor as described above, the devolatilization of the monohydroxy compound and the like can be easily performed in the subsequent step.

The residual amount of the monohydroxy compound is preferably small, but if the residual amount is reduced to less than 100 mass ppm, it is necessary to use an operation condition in which the amount of one terminal group is extremely reduced and the pressure of the polymerization reactor is maintained at a high vacuum. In this case, as described above, it is difficult to maintain the molecular weight of the obtained polycarbonate resin (a) at a constant level, and therefore, the molecular weight is usually 100 mass ppm or more, preferably 150 mass ppm or more.

From the viewpoint of effective utilization of resources, the monohydroxy compound produced by the side reaction is preferably purified as necessary and reused as a raw material for another compound. For example, when the monohydroxy compound is phenol, it can be used as a raw material for diphenyl carbonate, bisphenol A, or the like.

The glass transition temperature of the polycarbonate resin (A) is preferably 90 ℃ or higher. When the glass transition temperature is less than 90 ℃, the resin composition may have difficulty in achieving a balance between heat resistance and biomass content. From the viewpoint of further improving the balance between the heat resistance and the biomass content, the glass transition temperature of the polycarbonate resin (a) is more preferably 100 ℃ or higher, still more preferably 110 ℃ or higher, and particularly preferably 120 ℃ or higher. On the other hand, the glass transition temperature of the polycarbonate resin (A) is preferably 170 ℃ or lower. When the glass transition temperature exceeds 170 ℃, the melt viscosity during the polymerization becomes high, and it becomes difficult to obtain a polymer having a sufficient molecular weight. In addition, in the method of increasing the molecular weight by lowering the melt viscosity by increasing the polymerization temperature, the heat resistance of the constituent unit (a) is insufficient, and there is a possibility that coloring is easily caused. From the viewpoint of improving the balance between the molecular weight and the prevention of coloration, the glass transition temperature of the polycarbonate resin (a) is more preferably 165 ℃ or lower, still more preferably 160 ℃ or lower, and particularly preferably 150 ℃ or lower.

The molecular weight of the polycarbonate resin (a) can be expressed in reduced viscosity, and a higher reduced viscosity indicates a higher molecular weight. If the reduced viscosity of the polycarbonate resin (a) is too low, the mechanical strength of the molded article may be lowered. Therefore, the reduced viscosity is usually 0.30dL/g or more, preferably 0.33dL/g or more. On the other hand, if the reduced viscosity is too high, fluidity at the time of molding tends to be lowered, and productivity or processability tends to be lowered. Therefore, the reduced viscosity is usually 1.20dL/g or less, preferably 1.00dL/g or less, and more preferably 0.80dL/g or less. The reduced viscosity of the polycarbonate resin (A) was measured at a temperature of 20.0 ℃ C. + -0.1 ℃ C. using an Ubbelohde viscosity tube, using a solution in which the concentration of the resin composition was precisely adjusted to 0.6g/dL using methylene chloride as a solvent. The details of the method for measuring the reduced viscosity are described in examples.

The melt viscosity of the polycarbonate resin (a) is preferably 400Pa · s or more and 3000Pa · s or less, more preferably 600Pa · s or more and 2500Pa · s or less, and particularly preferably 800Pa · s or more and 2000Pa · s or less. If the melt viscosity of the polycarbonate resin (a) is lower than the above range, a molded article of the resin composition may become brittle and may not be a material having sufficient mechanical properties. On the other hand, if the melt viscosity is higher than the above range, the flow may be insufficient during molding processing to impair the appearance of the molded article, or the dimensional accuracy may be deteriorated. In addition, there is a concern that the temperature of the resin may be increased by shear heat generation to cause coloring or foaming. In the present specification, the melt viscosity refers to a melt viscosity measured by a capillary rheometer (manufactured by Toyo Seiki Seisaku-Sho Ltd.)]Measured temperature 240 ℃ and shear rate 91.2sec^-1Melt viscosity of (b). The details of the method for measuring the melt viscosity are described in the examples below.

The polycarbonate resin (a) preferably contains a catalyst deactivator. The catalyst deactivator is not particularly limited as long as it is an acidic substance and has a function of deactivating the polymerization catalyst, and examples thereof include: sulfonium salts such as phosphoric acid, trimethyl phosphate, triethyl phosphate, phosphorous acid, tetrabutylsulfonium octylsulfonate, tetramethylsulfonium benzenesulfonate, tetrabutylsulfonium dodecylbenzenesulfonate, and tetrabutylsulfonium p-toluenesulfonate; ammonium salts such as tetramethylammonium decylsulfonate and tetrabutylammonium dodecylbenzenesulfonate; and alkyl esters such as methyl benzenesulfonate, butyl benzenesulfonate, methyl p-toluenesulfonate, butyl p-toluenesulfonate and ethyl hexadecylsulfonate.

The catalyst deactivator preferably contains a phosphorus compound (hereinafter referred to as a "specific phosphorus compound") containing any one of the partial structures represented by the following structural formula (10) or the following structural formula (11). The specific phosphorus-based compound is added after the end of the polycondensation reaction, i.e., for example, in the kneading step, the granulating step, or the like, whereby the polymerization catalyst described later is deactivated, and the subsequent polycondensation reaction can be prevented from proceeding unnecessarily. As a result, the progress of polycondensation at the time of heating the polycarbonate resin (a) in the molding step or the like can be suppressed, and the removal of the monohydroxy compound can be suppressed. In addition, by deactivating the polymerization catalyst, coloration of the polycarbonate resin (a) at high temperatures can be suppressed.

[ chemical formula 9]

[ chemical formula 10]

As the specific phosphorus-based compound containing a partial structure represented by the structural formula (10) or (11), phosphoric acid, phosphorous acid, phosphonic acid, hypophosphorous acid, polyphosphoric acid, phosphonate ester, acidic phosphate ester, and the like can be used. Of the specific phosphorus-based compounds, phosphorous acid, phosphonic acid, and phosphonic acid ester are more excellent in the catalyst deactivation and coloring suppression effects, and phosphorous acid is particularly preferable.

As the phosphonic acid, for example, the following compounds can be used. Phosphonic acid (phosphorous acid), methylphosphonic acid, ethylphosphonic acid, vinylphosphonic acid, decylphosphonic acid, phenylphosphonic acid, benzylphosphonic acid, aminomethylphosphonic acid, methylenediphosphonic acid, 1-hydroxyethane-1, 1-diphosphonic acid, 4-methoxyphenylphosphonic acid, nitrilotris (methylenephosphonic acid), propylphosphonic anhydride, and the like.

As the phosphonate, for example, the following compounds can be used. Dimethyl phosphonate, diethyl phosphonate, bis (2-ethylhexyl) phosphonate, dilauryl phosphonate, dioleyl phosphonate, diphenyl phosphonate, dibenzyl phosphonate, dimethyl methylphosphonate, diphenyl methylphosphonate, diethyl ethylphosphonate, diethyl benzylphosphonate, dimethyl phenylphosphonate, diethyl phenylphosphonate, dipropyl phenylphosphonate, diethyl methoxymethyl) phosphonate, diethyl vinylphosphonate, diethyl hydroxymethylphosphonate, dimethyl (2-hydroxyethyl) phosphonate, diethyl p-methylbenzylphosphonate, diethyl diethylphosphonoacetic acid, ethyl diethylphosphonoacetate, tert-butyl diethylphosphonoacetate, diethyl (4-chlorobenzyl) phosphonate, diethyl cyanophosphonate, diethyl cyanomethylphosphonate, diethyl 3, 5-di-tert-butyl-4-hydroxybenzylphosphonate, diethyl (di-tert-butyl-4-hydroxybenzylphosphonate), diethyl (di-n-butyl) phosphonate, diethyl (, Diethyl phosphonoacetaldehyde diethyl acetal, (methylthiomethyl) phosphonic acid diethyl ester, and the like.

As the acidic phosphate ester, for example, the following compounds can be used. Phosphoric acid diesters such as dimethyl phosphate, diethyl phosphate, divinyl phosphate, dipropyl phosphate, dibutyl phosphate, bis (butoxyethyl) phosphate, bis (2-ethylhexyl) phosphate, diisotridecyl phosphate, dioleyl phosphate, distearyl phosphate, diphenyl phosphate, dibenzyl phosphate, or a mixture of diesters and monoesters, diethyl chlorophosphate, stearyl phosphate, and the like.

The specific phosphorus-based compound may be used alone in1 kind, or may be used in combination in any ratio of 2 or more kinds.

The content of the specific phosphorus compound in the polycarbonate resin (a) is preferably 0.1 mass ppm or more and 5 mass ppm or less in terms of phosphorus atom. If the content of the specific phosphorus-based compound is too small, the effects of catalyst deactivation and suppression of coloring may become insufficient. On the other hand, if the content of the specific phosphorus-based compound is too large, the polycarbonate resin (a) may be colored. In this case, particularly in the durability test at high temperature and high humidity, the polycarbonate resin (a) is easily colored.

Further, by adjusting the content of the specific phosphorus-based compound in accordance with the amount of the polymerization catalyst, the effects of catalyst deactivation and suppression of coloration can be more reliably obtained. The content of the specific phosphorus-based compound is preferably 0.5-fold mol or more and 5-fold mol or less, more preferably 0.7-fold mol or more and 4-fold mol or less, and particularly preferably 0.8-fold mol or more and 3-fold mol or less, based on the amount of phosphorus atoms, based on 1mol of the metal atoms in the polymerization catalyst.

[ aromatic polycarbonate resin (B) ]

The aromatic polycarbonate resin (B) is a polycarbonate resin having, as a main structural unit, a structural unit derived from an aromatic dihydroxy compound represented by the following general formula (12).

[ chemical formula 11]

R in the above general formula (12)¹～R⁸Each independently represents a hydrogen atom or a substituent. Y represents a single bond or a 2-valent group. As R in the general formula (12)¹～R⁸The substituent(s) is an alkyl group having 1 to 10 carbon atoms which may have a substituent(s), an alkoxy group having 1 to 10 carbon atoms which may have a substituent(s), a halogen group, a haloalkyl group having 1 to 10 carbon atoms, or an aromatic group having 6 to 20 carbon atoms which may have a substituent(s). Among them, an alkyl group having 1 to 10 carbon atoms which may have a substituent or an aromatic group having 6 to 20 carbon atoms which may have a substituent is preferable. Examples of the 2-valent group of Y in the general formula (12) include: an alkylene group having a chain structure of 1 to 6 carbon atoms which may have a substituent, an alkylidene group having a chain structure of 1 to 6 carbon atoms which may have a substituent, an alkylene group having a cyclic structure of 3 to 6 carbon atoms which may have a substituent, an alkylidene group having a cyclic structure of 3 to 6 carbon atoms which may have a substituent, -O-, -S-, -CO-, or-SO₂-. Here, the substituent is not particularly limited as long as the effect of the present invention is not hindered, and the molecular weight is usually 200 or less. The substituent of the alkylene group having a chain structure of 1 to 6 carbon atoms is preferably an aryl group, and particularly preferably a phenyl group.

The aromatic polycarbonate resin (B) may be a homopolymer or a copolymer, and in the case of a copolymer, it is preferably a polycarbonate resin having the largest number of structural units derived from the dihydroxy compound represented by the above general formula (12) out of the total structural units derived from the dihydroxy compound. In the aromatic polycarbonate resin (B), the content ratio of the structural unit derived from the dihydroxy compound represented by the general formula (12) to 100 mol% of the total structural units derived from all dihydroxy compounds is more preferably 50 mol% or more, still more preferably 70 mol% or more, and particularly preferably 90 mol% or more.

The aromatic polycarbonate resin (B) may have a branched structure, a linear structure, or a mixture of a branched structure and a linear structure. Further, the aromatic polycarbonate resin (B) may contain a structural unit derived from a dihydroxy compound having a site represented by the above formula (1). However, in the case where the structural unit derived from the dihydroxy compound having a site represented by the above formula (1) is contained, a polycarbonate resin having a structural unit different from that of the polycarbonate resin (a) can be used.

The structural unit derived from the dihydroxy compound constituting the aromatic polycarbonate resin (B) is a structural unit obtained by removing a hydrogen atom from a hydroxyl group of the dihydroxy compound. Specific examples of the corresponding dihydroxy compound include the following dihydroxy compounds.

4,4' -biphenol, 2, 4' -biphenol, 3,3 ' -dimethyl-4, 4' -dihydroxy-1, 1 ' -biphenyl, 3,3 ' -dimethyl-2, 4' -dihydroxy-1, 1 ' -biphenyl, 3,3 ' -di (tert-butyl) -4, 4' -dihydroxy-1, 1 ' -biphenyl, 3,3 ', 5,5 ' -tetramethyl-4, 4' -dihydroxy-1, 1 ' -biphenyl, 3,3 ', 5,5 ' -tetra- (tert-butyl) -4, 4' -dihydroxy-1, 1 ' -biphenyl, 2 ', 3,3 ', 5,5 ' -hexamethyl-4, 4' -dihydroxy-1, biphenyl compounds such as 1' -biphenyl.

Bis (4-hydroxy-3, 5-dimethylphenyl) methane, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-3-methylphenyl) methane, 1-bis (4-hydroxyphenyl) ethane, 1-bis (4-hydroxyphenyl) propane, 2-bis (4-hydroxy-3-methylphenyl) propane, 2-bis (4-hydroxyphenyl) butane, 2-bis (4-hydroxyphenyl) pentane, 2-bis (4-hydroxyphenyl) -3-methylbutane, 2-bis (4-hydroxyphenyl) hexane, 2-bis (4-hydroxyphenyl) -4-methylpentane, bis (4-hydroxyphenyl) hexane, bis (4-hydroxyphenyl) -4-methylpentane, bis (4-hydroxyphenyl) propane, bis, 1, 1-bis (4-hydroxyphenyl) cyclopentane, 1-bis (4-hydroxyphenyl) cyclohexane, bis (3-phenyl-4-hydroxyphenyl) methane, 1-bis (3-phenyl-4-hydroxyphenyl) ethane, 1-bis (3-phenyl-4-hydroxyphenyl) propane, 2-bis (3-phenyl-4-hydroxyphenyl) propane, 1-bis (4-hydroxy-3-methylphenyl) ethane, 2-bis (4-hydroxy-3-ethylphenyl) propane, 2-bis (4-hydroxy-3-isopropylphenyl) propane, 2-bis (4-hydroxy-3-sec-butylphenyl) propane, 1-bis (3-hydroxyphenyl) cyclohexane, 1-bis (3-hydroxyphenyl) ethane, 1-bis (3-hydroxyphenyl) propane, 2-bis (4-hydroxy-3-sec-butylphenyl) propane, 2-, 1, 1-bis (4-hydroxy-3, 5-dimethylphenyl) ethane, 2-bis (4-hydroxy-3, 5-dimethylphenyl) propane, 1-bis (4-hydroxy-3, 6-dimethylphenyl) ethane, bis (4-hydroxy-2, 3, 5-trimethylphenyl) methane, 1-bis (4-hydroxy-2, 3, 5-trimethylphenyl) ethane, 2-bis (4-hydroxy-2, 3, 5-trimethylphenyl) propane, bis (4-hydroxy-2, 3, 5-trimethylphenyl) phenylmethane, 1-bis (4-hydroxy-2, 3, 5-trimethylphenyl) phenylethane, 1-bis (4-hydroxy-2, 3, 5-trimethylphenyl) phenylethane, 1, 1-bis (4-hydroxy-3, 3, 5-trimethylphenyl) cyclohexane, bis (4-hydroxyphenyl) phenylmethane, 1-bis (4-hydroxyphenyl) -1-phenylethane, 1-bis (4-hydroxyphenyl) -1-phenylpropane, bis (4-hydroxyphenyl) diphenylmethane, bis (4-hydroxyphenyl) dibenzylmethane, 4'- [1, 4-phenylenebis (1-methylethylidene) ] bis [ phenol ], 4' - [1, 4-phenylenebismethylene ] bis [ phenol ], 4'- [1, 4-phenylenebis (1-methylethylidene) ] bis [2, 6-dimethylphenol ], 4' - [1, 4-phenylenebismethylene bis [2, 6-dimethylphenol ], 4' - [1, 4-phenylenebismethylene ] bis [2,3, 6-trimethylphenol ], 4' - [1, 4-phenylenebis (1-methylethylidene) ] bis [2,3, 6-trimethylphenol ], 4' - [1, 3-phenylenebis (1-methylethylidene) ] bis [2,3, 6-trimethylphenol ], 4' -dihydroxydiphenyl ether, 4' -dihydroxydiphenyl sulfone, 4' -dihydroxydiphenyl sulfide, 3 ', 5,5 ' -tetramethyl-4, 4' -dihydroxydiphenyl ether, 3 ', 5,5 ' -tetramethyl-4, 4 '-dihydroxydiphenyl sulfone, 3', 5,5 '-tetramethyl-4, 4' -dihydroxydiphenyl sulfide phenolphthalein, 4'- [1, 4-phenylenebis (1-methylvinylene) ] bisphenol, 4' - [1, 4-phenylenebis (1-methylvinylene) ] bis [ 2-methylphenol ], (2-hydroxyphenyl) (4-hydroxyphenyl) methane, and bisphenol compounds such as (2-hydroxy-5-methylphenyl) (4-hydroxy-3-methylphenyl) methane, 1- (2-hydroxyphenyl) (4-hydroxyphenyl) ethane, 2- (2-hydroxyphenyl) (4-hydroxyphenyl) propane, and 1,1- (2-hydroxyphenyl) (4-hydroxyphenyl) propane.

Halogenated bisphenol compounds such as2, 2-bis (3, 5-dibromo-4-hydroxyphenyl) propane and 2, 2-bis (3, 5-dichloro-4-hydroxyphenyl) propane.

Among them, preferable dihydroxy compounds include: bis (4-hydroxy-3, 5-dimethylphenyl) methane, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-3-methylphenyl) methane, 1-bis (4-hydroxyphenyl) ethane, 2-bis (4-hydroxyphenyl) propane, 2-bis (4-hydroxy-3-methylphenyl) propane, 2-bis (4-hydroxy-3, 5-dimethylphenyl) propane, 1-bis (4-hydroxyphenyl) cyclohexane, 1-bis (4-hydroxy-3, 3, 5-trimethylphenyl) cyclohexane, bis (4-hydroxyphenyl) phenylmethane, 1-bis (4-hydroxyphenyl) -1-phenylethane, bis (4-hydroxyphenyl) methane, 1, 1-bis (4-hydroxyphenyl) -1-phenylpropane, bis (4-hydroxyphenyl) diphenylmethane, 2-hydroxyphenyl (4-hydroxyphenyl) methane, 2- (2-hydroxyphenyl) (4-hydroxyphenyl) propane.

Among them, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-3-methylphenyl) methane, bis (4-hydroxy-3, 5-methylphenyl) methane, 2-bis (4-hydroxyphenyl) propane, 2-bis (4-hydroxy-3-methylphenyl) propane, 2-bis (4-hydroxy-3, 5-dimethylphenyl) propane, 1-bis (4-hydroxyphenyl) cyclohexane, 1-bis (4-hydroxy-3, 3, 5-trimethylphenyl) cyclohexane are particularly preferable.

Any conventionally known method such as a phosgene method, an ester exchange method, a pyridine method and the like can be used for the production method of the aromatic polycarbonate resin (B). Hereinafter, a method for producing the aromatic polycarbonate resin (B) by the transesterification method will be described as an example.

The transesterification method is a production method in which a dihydroxy compound, a carbonic acid diester, a basic catalyst, and an acidic substance neutralizing the basic catalyst are added to perform melt transesterification polycondensation. Examples of the dihydroxy compound include the biphenyl compounds and bisphenol compounds exemplified above.

Typical examples of the carbonic acid diester include: diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, m-cresyl carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, diethyl carbonate, dimethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate, and the like. Among them, diphenyl carbonate is particularly preferably used.

The viscosity average molecular weight of the aromatic polycarbonate resin (B) is usually 8,000 or more and 30,000 or less, and preferably 10,000 or more and 25,000 or less, from the viewpoint of the balance between mechanical properties and molding processability. The reduced viscosity of the aromatic polycarbonate resin (B) is measured at a temperature of 20.0 ℃. + -. 0.1 ℃ with the polycarbonate concentration precisely adjusted to 0.60g/dl using methylene chloride as a solvent, and is usually in the range of 0.23dl/g to 0.72dl/g, preferably 0.27dl/g to 0.61 dl/g.

In the present invention, the aromatic polycarbonate resin (B) may be used alone in1 kind or in a mixture of 2 or more kinds.

[ Compound (C) ]

The compound (C) is at least one compound selected from the group consisting of the following formula (2) or (3) and a basic nitrogen-containing compound.

The compound represented by the general formula (2) is a compound represented by the following formula (2) or formula (3).

[ chemical formula 12]

[ chemical formula 13]

Specifically, there may be mentioned: dibutyl tin oxide (818-08-6), methylphenyl tin oxide, tetraethyl tin oxide, hexaethyl tin oxide, cyclohexyl tin oxide, didodecyl tin oxide, triethyl tin hydroxide (994-32-1), triphenyl tin hydroxide, triisobutyl tin acetate, dibutyl tin diacetate (1067-33-0), dibutyl tin dilaurate (77-58-7), dioctyl tin dilaurate (3648-18-8), diphenyl tin dilaurate, monobutyl tin trichloride (1118-46-3), dibutyl tin dichloride (683-18-1), tributyl tin chloride (1461-22-9), dibutyl tin sulfide, and monobutyl tin hydroxide (2273-43-0, MBTO _ MCC), and the like. Dibutyl tin dilaurate may be preferred.

As the other compound (C), stannic acid can be used, and in this case, there can be mentioned: alkyl stannoic acids such as methyl stannoic acid, ethyl stannoic acid, and butyl stannoic acid.

Examples of the basic nitrogen-containing compound include basic ammonium compounds and amine compounds. As the basic ammonium compound, for example, the following compounds can be used. Tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylethylammonium hydroxide, trimethylbenzylammonium hydroxide, trimethylphenylammonium hydroxide, triethylmethylammonium hydroxide, triethylbenzylammonium hydroxide, triethylphenylammonium hydroxide, tributylbenzylammonium hydroxide, tributylphenylammonium hydroxide, tetraphenylammonium hydroxide, benzyltriphenylammonium hydroxide, methyltriphenylammonium hydroxide, butyltriphenylammonium hydroxide, and the like.

The amount of the compound (C) added is 0.001 to 5 parts by weight per 100 parts by weight of the resin composition containing the polycarbonate resin (a) and the aromatic polycarbonate resin (B). Preferably 0.01 part by weight or more, and more preferably 0.05 part by weight or more. Further, it is preferably 3 parts by weight or less, and more preferably 2 parts by weight or less. When the amount is less than 0.001 part by weight, the effect of making transparent is insufficient, and when it is more than 5 parts by weight, the transparency is increased, but the coloring is remarkable, the decrease in molecular weight is large, and the mechanical strength is insufficient.

In the method of adding the compound (C), the solid compound may be supplied in a solid state, and the compound soluble in water or a solvent may be supplied as an aqueous solution or a solution. The polycarbonate resin may be added to the raw material, and in the case of an aqueous solution or solution, the polycarbonate resin may be fed from a raw material inlet of an extruder, or a liquid may be added from a cylinder using a pump or the like.

[ polycarbonate resin composition ]

The polycarbonate resin composition is preferably molded into a molded article having a thickness of 1mm, and has a total light transmittance in the thickness direction of 80% or more. The total light transmittance is more preferably 85% or more, still more preferably 88% or more, and particularly preferably 90% or more. The method for measuring the total light transmittance is described in the examples below. The haze can also be measured by the same method as the total linear transmittance.

In addition, in the polycarbonate resin composition, it is preferable that the glass transition temperature is single as measured by DSC method. The glass transition temperature of the polycarbonate resin composition is preferably 100 ℃ or higher and 200 ℃ or lower. In the case where the glass transition temperature is less than 100 ℃, there is a possibility that deformation may occur in a moist heat resistance test or a weather resistance test. On the other hand, when the glass transition temperature exceeds 200 ℃, the polycarbonate resin (a) component is easily thermally decomposed, and when it is left for a long period of time during molding, appearance defects such as silver streaks or foaming may occur. When a resin composition is produced, the polycarbonate resin (a) may be thermally deteriorated to lower the impact resistance. The glass transition temperature of the polycarbonate resin is more preferably 110 ℃ to 190 ℃, and still more preferably 120 ℃ to 180 ℃.

The polycarbonate resin composition exhibiting the above-mentioned predetermined total light transmittance and glass transition temperature comprises a polycarbonate resin (a) containing a structural unit derived from a compound represented by the above formula (1), an aromatic polycarbonate resin (B), and the above-mentioned specific compound (C), and can be obtained by adjusting the content of the compound (C) to the above-mentioned predetermined range.

The blending ratio of the polycarbonate resin (a) and the aromatic polycarbonate resin (B) in the polycarbonate resin composition may be arbitrarily selected depending on the desired physical properties. The weight ratio (A/B) of the polycarbonate resin (A) to the aromatic polycarbonate resin (B) is preferably 95/5 to 50/50, more preferably 90/10 to 60/40, from the viewpoint of improving the biomass content. If the amount deviates from the above range, it may be difficult to well balance the heat resistance, impact resistance and biomass content.

[ other additives ]

Various additives may be added to the polycarbonate resin composition. Examples of the additives include dyes and pigments, antioxidants, UV absorbers, light stabilizers, mold release agents, heat stabilizers, flame retardants, flame retardant aids, inorganic fillers, impact modifiers, hydrolysis inhibitors, foaming agents, and nucleating agents, and additives generally used for polycarbonate resins can be used.

"dye pigment"

Examples of the dye and pigment include: organic dyes and pigments such as inorganic pigments, organic pigments, and organic dyes.

Specific examples of the inorganic pigment include: carbon black; oxide pigments such as titanium oxide, zinc white, red iron oxide, chromium oxide, iron black, titanium yellow, zinc-iron brown, copper-chromium black, and copper-iron black.

Specific examples of the organic dye pigment such as an organic pigment and an organic dye include: phthalocyanine-based dye pigments; azo, thioindigo, perinone, perylene, quinacridone, dioxazine, isoindolinone, quinophthalone, and other condensed polycyclic dyes; anthraquinone-based, violet-ring ketone-based, perylene-based, methine-based, quinoline-based, heterocyclic-based, and methyl-based dyes and pigments.

These dyes and pigments may be used alone in1 kind, or may be used in combination in 2 or more kinds.

Among the organic dye pigments such as the inorganic pigments, organic pigments and organic dyes, inorganic pigments are preferred, and the inorganic pigments are used as colorants, whereby the molded articles can maintain a clear image for a long time even when used outdoors or the like.

The amount of the dye pigment is 0.05 parts by weight or more and 5 parts by weight or less based on 100 parts by weight of the total of the polycarbonate resin (A) and the aromatic polycarbonate resin (B). More preferably 0.05 parts by weight or more and 3 parts by weight or less, and still more preferably 0.1 parts by weight or more and 2 parts by weight or less. When the amount of the coloring agent is less than 0.05 part by weight, a dyed molded article having a sharp image is not easily obtained. When the amount is more than 5 parts by weight, the surface roughness of the molded article becomes large, and it is difficult to obtain a dyed molded article having a clear image.

"antioxidant"

As the antioxidant, a general antioxidant used in a resin can be used, but from the viewpoint of oxidation stability and thermal stability, a phosphite-based antioxidant, a sulfur-based antioxidant, and a phenol-based antioxidant are preferable. The amount of the antioxidant to be added is usually preferably 0.001 part by weight or more, more preferably 0.002 part by weight or more, and still more preferably 0.005 part by weight or more, based on 100 parts by weight of the total of the polycarbonate resin (a) and the aromatic polycarbonate resin (B). The amount of the antioxidant to be added is usually preferably 5 parts by weight or less, more preferably 3 parts by weight or less, and still more preferably 2 parts by weight or less, based on 100 parts by weight of the total. If the amount of the antioxidant added is more than 5 parts by weight, the mold may be contaminated during molding, and a molded article having an excellent surface appearance may not be obtained. If the amount is less than 0.001 parts by weight, a sufficient improvement effect with respect to molding stability tends not to be obtained.

(phosphite-based antioxidant)

Examples of phosphite antioxidants include: triphenyl phosphite, tris (nonylphenyl) phosphite, tris (2, 4-di-tert-butylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecylmonophenyl phosphite, dioctylmonophenyl phosphite, diisopropyl monophenyl phosphite, monobutyldiphenyl phosphite, monodecyl diphenyl phosphite, monooctyldiphenyl phosphite, bis (2, 6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, 2-methylenebis (4, 6-di-tert-butylphenyl) octyl phosphite, bis (nonylphenyl) pentaerythritol diphosphite, bis (2, 4-di-tert-butylphenyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite or the like.

Among them, trisnonylphenyl phosphite, tris (2, 4-di-t-butylphenyl) phosphite, bis (2, 4-di-t-butylphenyl) pentaerythritol diphosphite, bis (2, 6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite are preferably used. These compounds may be used in1 kind or in combination of 2 or more kinds.

(Sulfur-based antioxidant)

Examples of the sulfur-based antioxidant include: dilauryl-3, 3 '-thiodipropionate, ditridecyl-3, 3' -thiodipropionate, dimyristyl-3, 3 '-thiodipropionate, distearyl-3, 3' -thiodipropionate, lauryl stearyl-3, 3 '-thiodipropionate, pentaerythritol tetrakis (3-laurylthiopropionate), bis [ 2-methyl-4- (3-laurylthiopropionyloxy) -5-tert-butylphenyl ] sulfide, octadecyl disulfide, mercaptobenzimidazole, 2-mercapto-6-methylbenzimidazole, 1' -thiobis (2-naphthol), and the like. Among the above, pentaerythritol tetrakis (3-laurylthiopropionate) is preferred. These compounds may be used in1 kind or in combination of 2 or more kinds.

(phenol antioxidant)

Examples of the phenolic antioxidant include pentaerythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (3-laurylthiopropionate), glycerol-3-stearylthiopropionate, 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-hexamethylenebis (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, 4 '-biphenylenediphosphonic acid tetrakis (2, 4-di-tert-butyl-4-hydroxyphenyl) propionyl ester, 3, 5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 4' -biphenylenediphosphonic acid tetrakis (2, 3, 5-di-tert-butyl-4-hydroxyphenyl) propionyl ester, 1, 5-dimethyl-2- [3- (3, 5-tert-butyl-4-hydroxyphenyl) ethyl ] phenyl ] phenol, 5-tert-methyl-4-oxa-4-hydroxy-phenyl ] isocyanurate, and the like.

Of these compounds, aromatic monohydroxy compounds in which 1 or more alkyl groups having 5 or more carbon atoms are substituted are preferable, and specifically, octadecyl-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, pentaerythritol-tetrakis {3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate }, are preferable, 1, 6-hexanediol-bis [3- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate ], 1,3, 5-trimethyl-2, 4, 6-tris (3, 5-di-t-butyl-4-hydroxybenzyl) benzene, etc., and pentaerythritol-tetrakis {3- (3, 5-di-t-butyl-4-hydroxyphenyl) propionate is more preferable. These compounds may be used in1 kind or in combination of 2 or more kinds.

UV absorbers "

Examples of the ultraviolet absorber include: benzotriazole-based compounds, benzophenone-based compounds, triazine-based compounds, benzoate-based compounds, hindered amine-based compounds, phenyl salicylate-based compounds, cyanoacrylate-based compounds, malonate-based compounds, oxalanilide-based compounds, and the like. These may be used alone in1 kind or in combination of 2 or more kinds.

More specific examples of the benzotriazole-based compound include: 2- (2 ' -hydroxy-3 ' -methyl-5 ' -hexylphenyl) benzotriazole, 2- (2 ' -hydroxy-3 ' -tert-butyl-5 ' -hexylphenyl) benzotriazole, 2- (2 ' -hydroxy-3 ', 5 ' -di-tert-butylphenyl) benzotriazole, 2- (2 ' -hydroxy-3 ' -methyl-5 ' -tert-octylphenyl) benzotriazole, 2- (2 ' -hydroxy-5 ' -tert-dodecylphenyl) benzotriazole, 2- (2 ' -hydroxy-3 ' -methyl-5 ' -tert-dodecylphenyl) benzotriazole, 2- (2 ' -hydroxy-5 ' -tert-butylphenyl) benzotriazole, benzotriazole derivatives thereof, and the like, Methyl-3- (3- (2H-benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl) propionate, and the like.

Examples of the triazine compound include: 2- [4- [ (2-hydroxy-3-dodecyloxypropyl) oxy ] -2-hydroxyphenyl ] -4, 6-bis (2, 4-dimethylphenyl) -1,3, 5-triazine, 2, 4-bis (2, 4-dimethylphenyl) -6- (2-hydroxy-4-isooctyloxyphenyl) -s-triazine, 2- (4, 6-diphenyl-1, 3, 5-triazin-2-yl) -5- [ (hexyl) oxy ] -phenol (BASF Japan, Tinuvin1577FF), and the like.

Examples of the hydroxybenzophenone-based compound include: 2,2 ' -dihydroxybenzophenone, 2 ', 4,4' -tetrahydroxybenzophenone, 2-hydroxy-4-octoxybenzophenone, and the like.

Examples of the cyanoacrylate-based compound include: ethyl-2-cyano-3, 3-diphenylacrylate, 2' -ethylhexyl-2-cyano-3, 3-diphenylacrylate, and the like.

Examples of the malonate-based compound include: 2- (1-arylalkylidene) malonates. Among them, preferred are [ (4-methoxyphenyl) -methylene ] -dimethyl malonate (manufactured by Clariant Co., Ltd., HostavinnPR-25) and dimethyl 2- (p-methoxybenzylidene) malonate.

Examples of the oxalanilide compound include: 2-Ethyl-2' -ethoxy-oxalanilide (Sanduvor VSU, manufactured by Clariant corporation), and the like.

Among them, 2- (2 ' -hydroxy-3 ' -tert-butyl-5 ' -hexylphenyl) benzotriazole, 2- (2 ' -hydroxy-5 ' -tert-butylphenyl) benzotriazole, 2- [4- [ (2-hydroxy-3-dodecyloxypropyl) oxy ] -2-hydroxyphenyl ] -4, 6-bis (2, 4-dimethylphenyl) -1,3, 5-triazine, and 2,2 ', 4' -tetrahydroxybenzophenone are preferable.

Light stabilizer "

Examples of the light stabilizer include: the molecular weight of the hindered amine light stabilizer is preferably 1000 or less, more preferably 900 or less. If the molecular weight exceeds 1000, sufficient weather resistance may not be obtained when the composition is molded. The molecular weight is preferably 300 or more, more preferably 400 or more. When the molecular weight is less than 300, heat resistance may be poor, and a mold may be contaminated during molding, so that a molded article having an excellent surface appearance may not be obtained. Further, a compound having a piperidine structure is preferable. The piperidine structure defined herein may be an amine structure of a saturated six-membered ring, and includes a structure in which a part of the piperidine structure is substituted with a substituent. Examples of the substituent include an alkyl group having 4 or less carbon atoms, and a methyl group is particularly preferable. Particularly preferred are compounds having a plurality of piperidine structures, and compounds in which these plurality of piperidine structures are linked by an ester structure are preferred.

Examples of such a light stabilizer include condensates of 4-piperidinol-2, 2,6, 6-tetramethyl-4-benzoate, bis (2,2,6, 6-tetramethyl-piperidyl) sebacate, bis (1,2,2,6, 6-pentamethyl-4-piperidyl) sebacate, tetrakis (2,2,6, 6-tetramethylpiperidine-4-carboxylic acid) 1,2,3, 4-butanetetrayl, condensates of 2,2,6, 6-tetramethyl-piperidinol with tridecyl alcohol and 1,2,3, 4-butanetetracarboxylic acid, 1,2,2,6, 6-pentamethyl-4-piperidyl, and condensates of tridecyl alcohol and tridecyl-1, 2,3, 4-butanetetracarboxylate, bis (1,2,3,6, 6-pentamethyl-4-piperidyl) [3, 5-bis (1, 1-dimethylethyl) -4-hydroxyphenyl ] methyl ] butyl malonate, bis (1, 1-dimethylethyl) -4-hydroxyphenyl ] propane diacid, bis (1,2,3,6, 6-tetramethylbutyl) propane-bis (1,2, 6-bis (1, 6-tetramethylpiperidyl) -4-piperidyl) piperidine, bis (1,2,3, 6-tetramethylpiperidyl) piperidine, 5-bis (1,2, 6-bis (1, 6-tetramethylbutyl) 4-hydroxyethoxy) -2, 6-1, 6-tetramethylpiperidine), bis (1, 6-tetramethylpiperidine) propane-bis (1, 6-tetramethylpiperidine) propane-4-tetramethylpiperidine), and bis (1, 6-tetramethylpiperidine), condensation products of bis (1, 6-tetramethylpiperidine), 2, 6-butanediamine, 6-tetramethylpiperidine), and bis (1, 6-tetramethylpiperidine), and bis (1, 6-tetramethylpiperidine) piperidine), and 1, 5-bis (1, 6-4-bis (1, 6-tetramethylbutyl) piperidine), and 5-bis (1, 6-bis (1, 6-bis-.

The content of the light stabilizer is preferably 0.001 parts by weight or more and 5 parts by weight or less based on 100 parts by weight of the total of the polycarbonate resin (a) and the aromatic polycarbonate resin (B). More preferably 0.005 to 3 parts by weight, and still more preferably 0.01 to 1 part by weight. When the amount of the hindered amine-based light stabilizer added is more than 5 parts by weight, coloring tends to occur, and a jet black having a deep and clear feeling is not easily obtained even when a colorant is added. If the amount is less than 0.001 part by weight, sufficient weather resistance may not be obtained when the polycarbonate resin composition is used for, for example, interior and exterior automotive parts. In addition, the aromatic polycarbonate resin (B) tends to be easily decomposed by the hindered amine light stabilizer. Therefore, when the amount of the aromatic polycarbonate resin (B) is large, the amount of the light stabilizer to be added is preferably carefully set in the ratio of the polycarbonate resin (a) to the aromatic polycarbonate resin (B).

Release agent "

The polycarbonate resin composition may contain, as a mold release agent for imparting mold releasability during molding, 0.0001 to 2 parts by weight of a fatty acid ester of a polyhydric alcohol per 100 parts by weight of the polycarbonate resin.

When the content of the fatty acid ester of the polyhydric alcohol is less than 0.0001 part by weight, the addition effect may not be sufficiently obtained, and the molded article may crack due to poor mold release during mold release in molding. On the other hand, when the amount exceeds 2 parts by weight, the resin composition may be clouded or the amount of the deposit adhering to the mold during molding may increase. The content of the fatty acid ester of the polyhydric alcohol is more preferably 0.01 part by weight or more and 1.5 parts by weight or less, and still more preferably 0.1 part by weight or more and 1 part by weight or less.

The fatty acid ester of a polyhydric alcohol is preferably a partial ester or a full ester of a polyhydric alcohol having 1 to 20 carbon atoms and a saturated fatty acid having 10 to 30 carbon atoms. Examples of partial esters or full esters of such polyhydric alcohols and saturated fatty acids include: stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride, stearic acid sorbitan ester, behenic acid monoglyceride, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tetrastearate, pentaerythritol tetrapelargonate, propylene glycol monostearate, isopropyl palmitate, sorbitan monostearate, and the like. Among them, stearic acid monoglyceride, stearic acid triglyceride, and pentaerythritol tetrastearate are preferably used.

From the viewpoint of heat resistance and moisture resistance, full esters are more preferable as the fatty acid esters of polyhydric alcohols.

The fatty acid is preferably a higher fatty acid, and more preferably a saturated fatty acid having 10 to 30 carbon atoms. Examples of such fatty acids include: myristic acid, lauric acid, palmitic acid, stearic acid, behenic acid, and the like.

Among fatty acid esters of polyhydric alcohols, ethylene glycol is preferable as the polyhydric alcohol. In this case, when added to a resin, the releasability can be improved without impairing the transparency of the resin.

The fatty acid ester of the polyhydric alcohol is preferably a fatty acid diester of a dihydric alcohol. In this case, when added to the resin, the molecular weight of the resin composition can be suppressed from decreasing in a hot and humid environment.

In the present embodiment, the timing and method of adding the release agent to the polycarbonate resin composition are not particularly limited. Examples of the addition timing include: when the polymerization reaction in the case of producing a polycarbonate resin by the transesterification method is completed; further, regardless of the polymerization method, the polycarbonate resin composition is in a molten state during kneading of the polycarbonate resin composition and other compounding agents; and blending or kneading the polycarbonate resin composition in a solid state such as pellets or powder using an extruder or the like. Examples of the addition method include: a method of directly mixing or kneading a release agent with a polycarbonate resin composition; a method of adding the polycarbonate resin composition or another resin and a release agent in the form of a high-concentration master batch prepared by using a small amount of the polycarbonate resin composition or the other resin and the release agent.

"other resins"

The polycarbonate resin composition may be used AS a polymer alloy by kneading with 1 or 2 or more kinds of synthetic resins such AS aromatic polyesters, aliphatic polyesters, polyamides, polystyrenes, polyolefins, acrylic acids, amorphous polyolefins, ABS and AS, and biodegradable resins such AS polylactic acid and polybutylene succinate, for example, within a range not to impair the effects of the present invention.

Inorganic filler and organic filler "

In the polycarbonate resin composition, calcium silicate such as glass fiber, glass milled fiber, glass flake, glass bead, silica, alumina, titanium dioxide, calcium sulfate powder, gypsum whisker, barium sulfate, talc, mica, wollastonite, and the like may be added within a range in which the design properties can be maintained; inorganic fillers such as carbon black, graphite, iron powder, copper powder, molybdenum disulfide, silicon carbide fiber, silicon nitride fiber, brass fiber, stainless steel fiber, potassium titanate fiber, and whiskers thereof; and powdery organic fillers such as wood flour, bamboo powder, coconut starch, cork flour, and starch; a capsule-spherical organic filler such as crosslinked polyester, polystyrene, a styrene-acrylic acid copolymer, and urea resin; fibrous organic fillers such as carbon fibers, synthetic fibers, and natural fibers.

[ method for producing polycarbonate resin composition ]

The polycarbonate resin composition can be produced by the following steps: an addition step of adding the specific compound (C) in an amount of 0.5 ppm by weight or more and 1000 ppm by weight or less in terms of metal amount to the specific polycarbonate resin (a) and the aromatic polycarbonate resin (B); then, a reaction step of melt-reacting the polycarbonate resin (a) and the aromatic polycarbonate resin (B) is performed. In the reaction step, the presence of the compound (C) promotes the ester interchange reaction between the polycarbonate resin (A) and the aromatic polycarbonate resin (B), thereby obtaining a resin composition having high compatibility. The polycarbonate resin (a), the aromatic polycarbonate resin (B) and the compound (C) may be the same as those described above.

The polycarbonate resin composition can be produced as follows: the above components are mixed at a specific ratio simultaneously or in an arbitrary order by a mixer such as a tumbler mixer, a V-type mixer, a nauta mixer, a Banbury mixer, a mixing roll, or an extruder, and the mixture is produced. Among them, in the case of melt-mixing, more preferred is a substance which can be mixed in a state of reduced pressure.

[ formed article ]

The polycarbonate resin composition can be molded by a generally known method such as injection molding, extrusion molding, and compression molding. The molded article obtained by molding is excellent in color tone, transparency, heat resistance, weather resistance, optical properties, and mechanical strength, and contains few residual low-molecular components and foreign matters, and thus is suitable for interior parts for vehicles.

[ examples ]

The present invention will be described in further detail below with reference to examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded.

[ evaluation method ]

The physical properties and characteristics of the polycarbonate resin (a), the aromatic polycarbonate resin (B) and the resin composition were evaluated by the following methods.

(1) Determination of reduced viscosity

A sample of the polycarbonate resin (A) or the aromatic polycarbonate resin (B) was dissolved in methylene chloride to prepare a polycarbonate resin solution having a concentration of 0.6 g/dL. The solvent passage time t was measured at 20.0 ℃. + -. 0.1 ℃ using an Ubbelohde type viscosity tube manufactured by Senyou chemical industry Co₀And a solution passage time t, and a relative viscosity η calculated based on the following formula (i)_relThen from relative viscosity η_relThe specific viscosity η was determined based on the following formula (ii)_sp。

η_rel＝t/t₀···(i)

η_sp＝η_rel-1···(ii)

The reduced viscosity was determined by dividing the obtained specific viscosity η sp by the concentration c (g/dL) of the solution (η)_spAnd c) the reaction solution is mixed. The higher the value of the reduced viscosity, the larger the molecular weight.

(2) Determination of glass transition temperature (Tg)

The glass transition temperature was measured using a differential scanning calorimeter (DSC: modulated DSC 2910, TA America) under a nitrogen atmosphere at a temperature rise rate of 10 ℃/min, and all the glass transition temperatures are described as ○ in the case of having a single transition temperature and as x in the case of having 2 or more transition temperatures.

(3) Measurement of Total light transmittance

The total light transmittance was measured by a standard C light source using a hot-pressed sheet having a thickness of 1mmt (described later) and a haze meter (WGW, manufactured by Shanghai Shen Co., Ltd.) in accordance with GB2410-80 standard. By visual inspection, a visibly opaque condition is described as opaque.

(4) Elongation at break

Elongation at break was determined according to ASTM D638.

(5) Calculation of Biomass content

Radioactive carbon 14(C14) is produced by cosmic rays in the atmosphere at a certain rate and disappears at a certain rate (half-life: 5370 years), and therefore exists in a certain amount in nature. Plants that absorb carbon dioxide from the atmosphere contain a certain amount of this C14, and when felling or the like does not produce carbonation, they disappear at a certain rate, and therefore, a radiocarbon dating method is established using this property. Since fossil fuels are not affected by cosmic rays for a long time, C14 disappears completely. On the other hand, since the supply of the biologically-derived chemical has only elapsed a short time after the supply of C14 is stopped, the content of C14 can be said to be a substantially constant value.

The method for calculating the biomass content will be described in detail using the above method.

First, the ISB carbonate structural unit of ISB-PC is composed of 6 carbons of ISB derived from a biological source and 1 carbon derived from DPC of fossil fuel, and therefore, the biomass content of ISB-PC is the number of carbon atoms of the biological source: 6/total number of carbon atoms: 7-85.7%. Here, since the polymer chain is sufficiently long, the influence of the terminal can be ignored. In addition, in the case of a copolymerized polycarbonate resin as described in production example 1 described later, since CHDM is a fossil fuel-derived raw material, the biomass content of CHDM-PC is the number of carbon atoms of biological origin: 0/total number of carbon atoms: and 9-0%. When the ISB/CHDM of production example 1 was 70/30 mol%, the biomass content was 85.7% × 70 mol%: 60% because only the ISB-PC component was a biological source.

Next, as described in examples, the biomass content when the polycarbonate resin (a) and the aromatic polycarbonate resin (B) are blended is 0% since the aromatic polycarbonate resin (B) is a polymer produced from a fossil fuel-derived raw material. Examples since the polycarbonate resins were blended in a weight ratio, the molar mass (unit: g/mol) of each polycarbonate resin was calculated, and the molar mass was divided by the weight, thereby converting into a molar fraction. Then, the blended biomass content was calculated by the product of the biomass content of the above polycarbonate resin (a) and the mole fraction thereof. The biomass was calculated from only the resin component, and components such as the compound (C), the heat stabilizer, and the release agent were not considered.

[ materials used ]

Abbreviations for compounds used in the following examples and comparative examples, and manufacturers thereof are as follows.

< dihydroxy Compound >

ISB: isosorbide [ manufactured by Roquette fres corporation ]: raw material of biological origin

CHDM: 1, 4-cyclohexanedimethanol [ manufactured by SK Chemical Co. ]: feedstock derived from fossil fuel

< diester carbonate >

DPC: diphenyl carbonate [ manufactured by Mitsubishi chemical corporation ]: feedstock derived from fossil fuel

< Heat stabilizer (antioxidant) >

Irganox 1010: pentaerythritol tetrakis [3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ] [ manufactured by BASF corporation ]

AS 2112: tris (2, 4-di-tert-butylphenyl) phosphite [ (manufactured by ADEKA Co., Ltd.) (molecular weight 646.9)

< Release agent >

E-275: ethylene glycol distearate [ manufactured by Nichisu oil Co., Ltd ]

Production example 1 of polycarbonate resin (a) ═ D7340R

The polycarbonate resin was polymerized using a continuous polymerization apparatus composed of 3 vertical stirred reactors, 1 horizontal stirred reactor and a twin screw extruder. Specifically, ISB, CHDM, and DPC were melted in a tank, and ISB, CHDM, and DPC were continuously supplied to the 1 st vertical stirred reactor at a flow rate of 35.2kg/hr, 14.9kg/hr, and 74.5kg/hr (molar ratio, ISB/CHDM/DPC is 0.700/0.300/1.010). Meanwhile, an aqueous solution of calcium acetate monohydrate as a catalyst was supplied to the 1 st vertical stirred reactor so as to be 1.5. mu. mol with respect to 1mol of the total dihydroxy compound. The reaction temperature, internal pressure and residence time of each reactor were set as 1 st vertical stirred reactor: 190 ℃, 25kPa, 90 minutes, vertical stirred reactor 2: 195 ℃,10 kPa, 45 minutes, No. 3 vertical stirred reactor: 210 ℃, 3kPa, 45 minutes, horizontal stirred reactor 4: at 225 ℃ under 0.5kPa for 90 minutes. The reaction was carried out while slightly adjusting the internal pressure of the horizontal stirred reactor 4 so that the reduced viscosity of the polycarbonate resin obtained was 0.41dL/g to 0.43 dL/g.

The polycarbonate resin was taken out from the 4 th horizontal stirred reactor in an amount of 60kg/hr, and then supplied in a molten state directly to a vented twin-screw extruder (TEX 30 α, L/D: 42, made by Japan Steel works, Ltd.) the polycarbonate resin passed through the extruder was passed through a candle filter (SUS 316) having a mesh opening of 10 μm in a molten state directly, and foreign matters were filtered.

The extruder had 3 vacuum vents, in which the residual low molecular weight components in the resin were devolatilized and removed. 2000 ppm by mass of water was added to the resin in front of the 2 nd exhaust port to carry out water injection and devolatilization. Irganox1010, AS2112 and E-275 were added in an amount of 0.1 part by mass, 0.05 part by mass and 0.3 part by mass, respectively, to 100 parts by mass of the polycarbonate resin in front of the 3 rd exhaust port. The above procedure gave an ISB/CHDM copolymer polycarbonate resin. The polycarbonate resin (A) obtained in production example 1 was referred to as "PC-A1".

Production example 2 of polycarbonate resin (a) ═ D5360R

A resin was prepared in the same manner as in production example 1 above except that the amount of each raw material supplied to the reactor was 25.4kg/hr of ISB, 25.0kg/hr of CHDM, and 74.8kg/hr of DPC (ISB/CHDM/DPC being 0.500/0.500/1.006 in terms of molar ratio), and 1mol of an aqueous solution of calcium acetate monohydrate to the total of dihydroxy compounds was 1.5 μmol, and the reduction viscosity of the obtained polycarbonate resin was changed from 0.60dL/g to 0.63dL/g, thereby obtaining a polycarbonate resin having an ISB/CHDM molar ratio of 50/50 mol%. The polycarbonate resin (A) obtained in production example 2 was referred to as "PC-A2".

Production example 3 of polycarbonate resin (a) ═ ISB/CHDM 27/73 mol%

In a polymerization reaction device provided with stirring blades and a reflux condenser controlled at 100 ℃, the molar ratio of ISB/CHDM/DPC/calcium acetate monohydrate is 0.27/0.73/1.00/6.5X 10^-7Then, DPC and calcium acetate monohydrate were charged in ISB and CHDM and distilled and purified so that the chloride ion concentration was 10ppb or less, and nitrogen substitution was sufficiently performed. Then, the contents were melted and homogenized while heating with a heating medium and starting stirring at a time when the internal temperature was 100 ℃. Then, the temperature was increased to 210 ℃ over 40 minutes, and the internal temperature was controlled to 210 ℃ so as to maintain the temperature, while the pressure was reduced to 210 ℃ and then 13.3kPa (absolute pressure, the same applies hereinafter) over 90 minutes, and the pressure was maintained for 30 minutes.

Phenol vapor generated by a side reaction together with the polymerization reaction is introduced into a reflux condenser using as a refrigerant vapor at an inlet temperature controlled to 100 ℃ as a reflux condenser, and a monomer component contained in the phenol vapor in a certain amount is returned to the polymerization reactor, and the phenol vapor that has not been condensed is then introduced into a condenser using as a refrigerant warm water at 45 ℃ and recovered.

After the contents subjected to the oligomerization were once repressurized to atmospheric pressure, the reaction mixture was transferred to another polymerization reactor equipped with a stirring blade and a controlled reflux cooler as described above, and the temperature and pressure were increased to 210 ℃ and 200Pa for 60 minutes after the start of temperature increase and pressure reduction. Then, the internal temperature was set to 220 ℃ and the pressure was set to 133Pa or less for 20 minutes, and the pressure was restored at the time when the predetermined stirring power was reached, and the polycarbonate resin in a molten state from the outlet of the polymerization reaction apparatus was pelletized by a pelletizer to obtain pellets. The reduced viscosity was 0.63 dl/g.

The above operation gave a polycarbonate resin having an ISB/CHDM molar ratio of 27/73 mol%. The polycarbonate resin (A) obtained in production example 3 was referred to as "PC-A3".

[ aromatic polycarbonate resin (B) ]

PC-B1: ifpilon S3000 manufactured by Mitsubishi engineering plastics: aromatic polycarbonate resin containing 100 mol% of bisphenol A structural unit, product of interfacial polymerization method, reduced viscosity of 0.46 dl/g): feedstock derived from fossil fuel

PC-B2: NOVAREX 7022, mitsubishi engineering plastics: aromatic polycarbonate resin containing 100 mol% of bisphenol A structural unit, product of transesterification method, reduced viscosity of 0.47 dl/g): feedstock derived from fossil fuel

[ Compound (C) ]

C-1: dibutyl tin dilaurate (dibutyl dilaurate) (manufactured by Aladdin Co., Ltd.)

C-2: tetramethylhydroxylammonium (manufactured by Aladdin Co., Ltd.)

[ example 1]

50 parts by weight of PC-A2 obtained in production example 2, 50 parts by weight of PC-B1 as the aromatic polycarbonate resin (B) and 0.03 part by weight of C-1 as the compound (C) were put into a small kneader (Rheochard 300P, manufactured by Hakke) and kneaded. The resulting mixture was kneaded at a rotation speed of 80rpm and a set temperature of 250 ℃ for 8 minutes to obtain a pelletized resin. The obtained pellets were dried at 80 ℃ for 12 hours by a vacuum dryer, then pressed at a set temperature of 250 ℃ and a pressure of 10MPa for 10 minutes by a hot press (manufactured by Shanghai Seama rubber and Plastic machinery Co., Ltd.), and then solidified by cold pressing to obtain test pieces of 50mm X1 mmt. The results are shown in Table 1.

[ example 2]

The procedure of example 1 was repeated except that C-1 in example 1 was changed to 0.2 parts by weight. The results are shown in Table 1.

[ example 3]

The procedure of example 1 was repeated except that the PC-A2 obtained in production example 2 of example 1 was changed to the PC-A1 obtained in production example 1. The results are shown in Table 1.

[ example 4]

The procedure of example 1 was repeated, except that C-1 was used in example 1 in an amount of 30.05 parts by weight instead of C-1. The results are shown in Table 1.

[ example 5]

The procedure of example 1 was repeated, except that C-1 was used in example 3 in an amount of 30.2 parts by weight instead of C-1. The results are shown in Table 1.

[ example 6]

The procedure of example 1 was repeated, except that C-40.05 parts by weight was used instead of C-1 in example 1. The results are shown in Table 1.

[ example 7]

The procedure of example 1 was repeated, except that C-1 was used in example 3 in an amount of 40.2 parts by weight instead of C-1. The results are shown in Table 1.

Comparative example 1

The procedure was carried out in the same manner as in example 1 except that 0 part by weight of C-1 was used in example 1. The results are shown in Table 1.

Comparative example 2

The procedure was carried out in the same manner as in example 2 except that 0 part by weight of C-1 was used in example 2. The results are shown in Table 1.

Comparative example 3

The procedure of comparative example 1 was repeated except that PC-A1 was used in comparative example 2 instead of PC-A3 and the kneading time was changed to 5 minutes. The results are shown in Table 1.

Comparative example 4

The procedure of comparative example 1 was repeated except that PC-A3 was changed to 70 parts by weight and PC-B3 was changed to 30 parts by weight in comparative example 3. The results are shown in Table 1.

Further, such a polycarbonate resin composition has excellent transparency and has a biomass content, heat resistance and mechanical strength in a highly balanced manner.

Claims

1. A polycarbonate resin composition comprising a polycarbonate resin (A) containing a structural unit derived from a compound represented by the following formula (1), an aromatic polycarbonate resin (B), and at least one or more compounds (C) selected from a tin compound represented by the following formula (2) or (3) and a basic nitrogen-containing compound, wherein the amount of the compound (C) added is 0.001 to 5 parts by weight based on 100 parts by weight of a resin composition comprising the polycarbonate resin (A) and the aromatic polycarbonate resin (B),

the mass ratio of the polycarbonate resin (A) to the aromatic polycarbonate resin (B) is 95/5-50/50,

the polycarbonate resin (A) has a content of a structural unit derived from a dihydroxy compound represented by the following formula (1) of 60 mol% or more based on 100 mol% of structural units derived from all dihydroxy compounds,

[ chemical formula 1]

[ chemical formula 2]

[ chemical formula 2]

Wherein R represents an alkyl group or an aryl group having 1 to 15 carbon atoms, X1 to X4 represent 1-valent groups each containing an alkyl group having 1 to 15 carbon atoms, an aryl group, an allyloxy group, a cyclohexyl group, a hydroxyl group and a halogen, and may be the same or different, and X5 represents a sulfur or oxygen atom.

2. The polycarbonate resin composition of claim 1, wherein the polycarbonate resin composition has only one glass transition temperature as determined by differential scanning calorimetry.

3. The polycarbonate resin composition according to claim 1 or 2, wherein the polycarbonate resin composition has a total light transmittance of 80% or more in a molded article having a thickness of 1 mm.

4. The polycarbonate resin composition according to claim 3, wherein the polycarbonate resin composition has a glass transition temperature of 90 ℃ or more and 200 ℃ or less as measured by differential scanning calorimetry.