JP2023133092A - Polycarbonate resin composition and molding - Google Patents

Abstract

To provide a polycarbonate resin composition that enables the production of a molding with excellent transparency, heat resistance, and flaw resistance, and a molding thereof.SOLUTION: The present invention provides a polycarbonate resin composition that contains polycarbonate resin and silica particles, and a molding thereof. The polycarbonate resin includes at least a structural unit A derived from a dihydroxy compound represented by the formula (1). The silica particles have an average primary particle size of less than 100 nm.SELECTED DRAWING: None

Description

The present invention relates to a polycarbonate resin composition containing a polycarbonate resin having a structural unit derived from a specific dihydroxy compound and silica particles, and a molded article thereof.

Polycarbonate resin has advantages such as transparency, heat resistance, and mechanical strength, and is widely used as a so-called engineering plastic in the optical field such as electrical and electronic parts, automobile parts, optical recording media, and lenses.

Among polycarbonate resins, studies have been made to improve the transparency and mechanical strength of aliphatic polycarbonate resins. For example, Patent Document 1 and Patent Document 3 describe blending amorphous silica in a specific proportion as an aliphatic polycarbonate in order to improve the transparency, blocking resistance, and mechanical strength of polypropylene carbonate. .

In recent years, polycarbonate resins using plant-derived raw materials such as isosorbide as monomer raw materials have been studied. Such polycarbonate resins are more advantageous than aliphatic polycarbonates in terms of mechanical strength, heat resistance, and transparency. Specifically, Patent Document 2 describes a polycarbonate resin using isosorbide as a monomer raw material as an aliphatic polycarbonate resin, and this polycarbonate resin is blended with glass powder or glass fiber to improve transparency and mechanical strength. It is stated that

Japanese Patent Application Publication No. 2014-19748 International Publication No. 2018/199033 pamphlet Japanese Patent Application Publication No. 2016-160323

However, in the polycarbonate resin composition described in Patent Document 2, clouding, coloring, etc. occurred in injection molded products, and transparency was insufficient. Another problem was that the surface was easily scratched.

The present invention has been made in view of this background, and it is an object of the present invention to provide a polycarbonate resin composition having excellent transparency, heat resistance, and scratch resistance, and a molded article thereof.

That is, the present invention has the following aspects.
[1] A polycarbonate resin containing at least a structural unit A derived from a dihydroxy compound represented by the following formula (1),
A polycarbonate resin composition containing silica particles having an average primary particle diameter of less than 100 nm.

[2] According to [1], the weight fraction of the structural unit A is 10% by weight or more and 90% by weight or less with respect to 100% by weight of structural units derived from all dihydroxy compounds constituting the polycarbonate resin. polycarbonate resin composition.
[3] The polycarbonate resin composition according to [1] or [2], wherein the silica particles are composed of amorphous silica.

[4] The polycarbonate according to any one of [1] to [3], wherein the content of the silica particles is 0.1 parts by weight or more and 10 parts by weight or less with respect to 100 parts by weight of the polycarbonate resin composition. Resin composition.
[5] The polycarbonate resin composition according to any one of [1] to [4], wherein the polycarbonate resin composition contains a dispersant.
[6] A molded article made of the polycarbonate resin composition according to any one of [1] to [5].

According to the above-mentioned polycarbonate resin composition, a molded article having excellent scratch resistance can be obtained while maintaining high transparency and heat resistance. In other words, the polycarbonate resin composition has excellent transparency, heat resistance, and scratch resistance. As a result, polycarbonate resin compositions are expected to be applied to injection molding fields such as automotive parts, electrical/electronic parts, and glass replacement applications, which require even higher specifications than conventional ones. In addition, the silica particles with an average primary particle diameter of less than 100 nm provide blocking resistance (that is, slipperiness) while maintaining high properties such as transparency and heat resistance, and the polycarbonate resin composition is suitable for film production. , Sheet field; Bottle and container field; Lens applications such as camera lenses, finder lenses, CCD lenses, CMOS lenses, etc.; Optical materials such as light diffusion sheets; Optical parts such as optical disks, immobilization of dyes, charge transfer agents, etc. It is also expected to be applied to binder applications. Further, as the dihydroxy compound represented by formula (1), isosorbide, which is abundantly available as a plant-derived resource and is produced from various easily available starches, can be used.

The embodiments of the present invention will be described in detail below, but the explanation of the configuration described below is an example (that is, a representative example) of the embodiments of the present invention, and the present invention does not exceed the gist thereof. It is not limited to the following contents. As used herein, the term "structural unit" refers to a specific partial structure that constitutes a resin and is included in a repeating structural unit. Specifically, "structural unit" refers to the partial structure sandwiched between adjacent linking groups in the polymer constituting the resin, and the polymerization-reactive group present in the terminal portion of the polymer and the polymerization-reactive group. A partial structure sandwiched between a connecting group and an adjacent linking group. More specifically, in the case of polycarbonate resin, a carbonyl group is a linking group, and a partial structure sandwiched between adjacent carbonyl groups is called a structural unit. Furthermore, when the expression "~" is used in this specification, it is used in a meaning that includes the numerical values or physical values described before and after it. In addition, numerical values or physical values described as upper limits and lower limits are used in a meaning that includes those values. Furthermore, "parts by weight" and "parts by mass" and "weight %" and "mass %" have substantially the same meaning.

<Raw materials for polycarbonate resin>
(dihydroxy compound)
The polycarbonate resin includes at least a structural unit derived from a dihydroxy compound represented by the following formula (1).

The dihydroxy compound represented by the above formula (1) (that is, dihydroxy compound A) includes isosorbide (that is, ISB), isomannide, and isoidet, which are stereoisomers. These may be used alone or in combination of two or more. Among these, ISB is the most preferred from the viewpoint of ease of acquisition and manufacture. ISB is an anhydrous sugar alcohol obtained by dehydration condensation of sorbitol, which is abundantly available as a plant-derived resource and is produced from various easily available starches.

The weight fraction of the structural unit A derived from the dihydroxy compound represented by the above formula (1) with respect to all the dihydroxy compounds constituting the polycarbonate resin is preferably from 10 to 90% by weight, and from 20 to 90% by weight. It is more preferably 90% by weight, and even more preferably 30 to 80% by weight. The higher the content of structural unit A, the higher the heat resistance, but the mechanical properties such as impact resistance and tensile elongation at break tend to decrease. Preferably, it is a copolymer with structural unit B that can be used.

Examples of the dihydroxy compound constituting the structural unit B (that is, dihydroxy compound B) include 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, and tricyclodecane dimethanol. It will be done. These may be used alone or in combination of two or more. Among them, 1,4-cyclohexanedimethanol and tricyclodecane dimethanol are most preferred from the viewpoint of ease of acquisition and production and from the viewpoint of improving mechanical properties such as impact resistance and tensile elongation at break of the polycarbonate resin.

The range of the weight fraction of the dihydroxy compound constituting the above-mentioned structural unit B with respect to all the dihydroxy compounds constituting the polycarbonate resin can be adjusted as appropriate depending on the desired physical properties. As the content of the structural unit B in the polycarbonate resin increases, the impact resistance increases, but since the content of the structural unit A relatively decreases, the heat resistance tends to decrease. From the viewpoint of improving mechanical properties such as impact resistance and heat resistance in a well-balanced manner, the weight fraction of structural unit B is 5 to 90% with respect to 100% by weight of structural units derived from all dihydroxy compounds constituting the polycarbonate resin. It is preferably % by weight, more preferably 10-80% by weight, even more preferably 15-70% by weight.

The polycarbonate resin contains a structural unit C derived from a dihydroxy compound (hereinafter appropriately referred to as "dihydroxy compound C") other than the above two types of dihydroxy compounds (that is, dihydroxy compound A and dihydroxy compound B). Good too. Examples of the dihydroxy compound C include dihydroxy compounds of linear aliphatic hydrocarbons, dihydroxy compounds of branched linear aliphatic hydrocarbons, dihydroxy compounds of alicyclic hydrocarbons other than dihydroxy compound B, oxyalkylene glycols, Examples include dihydroxy compounds having an ether group bonded to an aromatic group in the main chain, dihydroxy compounds having a heterocycle, aromatic bisphenols, and the like.

Examples of dihydroxy compounds of straight chain aliphatic hydrocarbons include ethylene glycol, 1,3-propanediol, 1,2-propanediol, 1,4-butanediol, 1,3-butanediol, and 1,2-butanediol. Examples include diol, 1,5-heptanediol, 1,6-hexanediol, 1,10-decanediol, 1,12-dodecanediol and the like.

Examples of the branched linear aliphatic hydrocarbon dihydroxy compound include neopentyl glycol, hexylene glycol, and the like.

Examples of dihydroxy compounds of alicyclic hydrocarbons include 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, tricyclodecane dimethanol, pentacyclopentadecane dimethanol, 2,6- Decalin dimethanol, 1,5-decalin dimethanol, 2,3-decalin dimethanol, 2,3-norbornane dimethanol, 2,5-norbornane dimethanol, 1,3-adamantanedimethanol, hydrogenated 2,2- Examples include dihydroxy compounds derived from terpene compounds such as bis(4-hydroxyphenyl)propane (that is, hydrogenated bisphenol A) and limonene.

Examples of oxyalkylene glycols include diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, polypropylene glycol, polytrimethylene glycol, polytetramethylene glycol, and the like.

Examples of dihydroxy compounds having an ether group bonded to an aromatic group in the main chain include 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene, 9,9-bis[4-(2- hydroxypropoxy)phenyl]fluorene, 9,9-bis[4-(2-hydroxyethoxy)-3-methylphenyl]fluorene, 9,9-bis[4-(2-hydroxypropoxy)-3-methylphenyl]fluorene , 9,9-bis[4-(2-hydroxyethoxy)-3-isopropylphenyl]fluorene, 9,9-bis[4-(2-hydroxyethoxy)-3-isobutylphenyl]fluorene, 9,9-bis [4-(2-hydroxyethoxy)-3-tert-butylphenyl]fluorene, 9,9-bis[4-(2-hydroxyethoxy)-3-cyclohexylphenyl]fluorene, 9,9-bis[4-( 2-hydroxyethoxy)-3-phenylphenyl]fluorene, 9,9-bis[4-(2-hydroxyethoxy)-3,5-dimethylphenyl]fluorene, 9,9-bis[4-(2-hydroxyethoxy) )-3-tert-butyl-6-methylphenyl]fluorene, 9,9-bis[4-(3-hydroxy-2,2-dimethylpropoxy)phenyl]fluorene, 2,2-bis[4-(2- hydroxyethoxy)phenyl]propane, 2,2-bis[4-(2-hydroxypropoxy)phenyl]propane, 1,3-bis(2-hydroxyethoxy)benzene, 4,4'-bis(2-hydroxyethoxy) Examples include biphenyl, bis[4-(2-hydroxyethoxy)phenyl]sulfone, and the like.
Examples of the dihydroxy compound having a heterocycle include spiroglycols represented by the following formula (2) and the following formula (3).

Examples of aromatic bisphenols include 2,2-bis(4-hydroxyphenyl)propane (that is, bisphenol A), 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, and 2,2-bis(4-hydroxyphenyl)propane (that is, bisphenol A). -bis(4-hydroxy-3,5-diethylphenyl)propane, 2,2-bis(4-hydroxy-(3,5-diphenyl)phenyl)propane, 2,2-bis(4-hydroxy-3,5 -dibromophenyl)propane, 2,2-bis(4-hydroxyphenyl)pentane, 2,4'-dihydroxy-diphenylmethane, bis(4-hydroxyphenyl)methane, bis(4-hydroxy-5-nitrophenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-2-ethylhexane, 1,1-bis(4-hydroxyphenyl)decane, 1,3-bis[2 -(4-hydroxyphenyl)-2-propyl]benzene, 2,2-bis(4-hydroxyphenyl)octane, 2,2-bis(4-hydroxyphenyl)nonane, 2,2-bis(4-hydroxyphenyl) ) Decane, 3,3-bis(4-hydroxyphenyl)pentane, 1,1-bis(4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenyl)sulfone, 2,4'-dihydroxydiphenylsulfone, bis(4 -hydroxyphenyl) sulfide, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dichlorodiphenyl ether, 4,4'-dihydroxy-2,5-diethoxydiphenyl ether, 9,9-bis( 4-hydroxyphenyl)fluorene, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, 9,9-bis(4-hydroxy-3-ethylphenyl)fluorene, (4-hydroxy-3-n- 9,9-bis(4-hydroxy-3-isopropylphenyl)fluorene, 9,9-bis(4-hydroxy-3-n-butylphenyl)fluorene, 9,9-bis(4-hydroxy -3-sec-butylphenyl)fluorene, 9,9-bis(4-hydroxy-3-tert-butylphenyl)fluorene, 9,9-bis(4-hydroxy-3-cyclohexylphenyl)fluorene, 9,9- Examples include bis(4-hydroxy-3-phenylphenyl)fluorene.

At least one of these dihydroxy compounds C may be used in combination with dihydroxy compound A, or dihydroxy compound A and dihydroxy compound B, depending on the required performance of the polycarbonate resin. From the viewpoint of further improving the color tone, weather resistance, and optical properties of the polycarbonate resin, it is preferable to use a dihydroxy compound that does not have an aromatic ring structure in its molecular structure as the dihydroxy compound C. That is, as the dihydroxy compound C, dihydroxy compounds of aliphatic hydrocarbons and dihydroxy compounds of alicyclic hydrocarbons are preferable, and these may be used in combination.

By using dihydroxy compound C in combination with dihydroxy compound A and dihydroxy compound B, it is also possible to obtain effects such as improving the flexibility and mechanical properties of the polycarbonate resin, and improving moldability. From the viewpoint of more reliably improving mechanical properties and heat resistance, the proportion of structural unit C derived from dihydroxy compound C is preferably 90 mol% with respect to 100 mol% of structural units derived from all dihydroxy compounds constituting the polycarbonate resin. The content is more preferably 30 mol% or less, further preferably 20 mol% or less.

Among the dihydroxy compounds C, the dihydroxy compounds containing aromatic components cause a decrease in the weather resistance of the polycarbonate resin, so the content of the aromatic dihydroxy compounds is preferably less than 10 mol%, and preferably less than 5 mol%. More preferably, it is less than 2 mol%, and most preferably 0.
All dihydroxy compounds used in the production of polycarbonate resins may contain stabilizers such as reducing agents, antioxidants, oxygen scavengers, light stabilizers, antacids, pH stabilizers or heat stabilizers. . Since the dihydroxy compound A tends to deteriorate particularly under acidic conditions, it is preferable that the dihydroxy compound contains a basic stabilizer.

(carbonic diester)
The polycarbonate resin is obtained by polycondensing these raw materials, for example, by transesterification, using a dihydroxy compound including the above-mentioned specific dihydroxy compound and a carbonic acid diester as raw materials. Examples of carbonic diesters include those represented by the following formula (4). As carbonic acid diesters, one type may be used alone or two or more types may be used.

In the above formula (4), A ¹ and A ² are each ^a substituted or unsubstituted aliphatic hydrocarbon group having 1 to 18 ^carbon atoms or a substituted or unsubstituted aromatic hydrocarbon group; may be the same or different. A ¹ and A ² are preferably substituted or unsubstituted aromatic hydrocarbon groups, more preferably unsubstituted aromatic hydrocarbon groups.

Examples of the carbonic acid diester represented by formula (4) include substituted diphenyl carbonates such as diphenyl carbonate (that is, DPC) and ditolyl carbonate. Further, examples of the carbonic acid diester represented by formula (4) include dimethyl carbonate, diethyl carbonate, di-t-butyl carbonate, and the like. Among these, diphenyl carbonate or substituted diphenyl carbonate is preferred, and diphenyl carbonate is more preferred. Note that the diester carbonate may contain impurities such as chloride ions, and the impurities may inhibit the polymerization reaction or deteriorate the hue of the obtained polycarbonate resin. From the viewpoint of preventing polymerization reaction inhibition and further improving transparency, it is preferable to use carbonate diester purified by distillation or the like, if necessary.

<Transesterification reaction catalyst>
The polycarbonate resin is produced, for example, by transesterifying the dihydroxy compound and carbonic acid diester described above. More specifically, it is obtained by transesterifying and removing by-product monohydroxy compounds and the like from the system.

During the transesterification reaction, polycondensation is carried out in the presence of a transesterification catalyst, and a transesterification catalyst (hereinafter appropriately referred to as a "catalyst" or "polymerization catalyst") that can be used in the production of polycarbonate resin is used. By selecting, the reaction rate or the quality of the polycarbonate resin obtained by polycondensation can be appropriately adjusted.

The catalyst is not limited as long as it can satisfy the transparency, hue, heat resistance, weather resistance, and mechanical strength of the produced polycarbonate resin. For example, metal compounds of Group 1 or Group 2 (hereinafter referred to as "Group 1" or "Group 2" as appropriate) in the long periodic table, as well as basic boron compounds, basic phosphorus compounds, and basic ammonium compounds. and basic compounds such as amine compounds. Preferably, Group 1 metal compounds and/or Group 2 metal compounds are used.

Examples of Group 1 metal compounds include sodium hydroxide, potassium hydroxide, lithium hydroxide, cesium hydroxide, sodium hydrogen carbonate, potassium hydrogen carbonate, lithium hydrogen carbonate, cesium hydrogen carbonate, 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 boroborophenylate, Potassium boroboronate, Lithium boroborophenylate, Cesium boroboronate, Sodium benzoate, Potassium benzoate, Lithium benzoate, Cesium benzoate, Disodium hydrogen phosphate, Dipotassium hydrogen phosphate, Phosphorus Dilithium oxyhydrogen, dicesium hydrogen phosphate, disodium phenylphosphate, dipotassium phenylphosphate, dilithium phenylphosphate, dicesium phenylphosphate, sodium, potassium, lithium, cesium alcoholates, phenolates, bisphenols Examples include the disodium salt, dipotassium salt, dilithium salt, and dicesium salt of A. Among these, lithium compounds are preferred from the viewpoint of further improving the polymerization activity and the hue of the resulting polycarbonate resin.

Examples of Group 2 metal compounds include 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, Examples include strontium carbonate, calcium acetate, barium acetate, magnesium acetate, strontium acetate, calcium stearate, barium stearate, magnesium stearate, strontium stearate, and the like. Among these, preferred are magnesium compounds, calcium compounds, and barium compounds. From the viewpoint of polymerization activity and the hue of the polycarbonate resin, magnesium compounds and/or calcium compounds are more preferred, and calcium compounds are even more preferred.

In addition, as a catalyst, it is also possible to use a basic compound such as a basic phosphorus compound, a basic ammonium compound, or an amine compound as an auxiliary together with the above Group 1 metal compound and/or Group 2 metal compound. It is particularly preferred to use only Group 1 metal compounds and/or Group 2 metal compounds.

Examples of the basic phosphorus compound include triethylphosphine, tri-n-propylphosphine, triisopropylphosphine, tri-n-butylphosphine, triphenylphosphine, tributylphosphine, and quaternary phosphonium salts.

Examples of the basic ammonium compound include 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, Examples include butyltriphenylammonium hydroxide.

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

The amount of the polymerization catalyst used is preferably 0.1 μmol to 300 μmol, more preferably 0.5 μmol to 100 μmol, and even more preferably 1 μmol to 50 μmol, per mol of all dihydroxy compounds used in the polymerization.
Among them, when using a compound containing at least one metal selected from the group consisting of Group 2 in the long period periodic table and lithium, especially when using a magnesium compound and/or a calcium compound, per 1 mol of total dihydroxy compounds. It is preferable to use a catalyst so that the amount of metal in the catalyst is 0.1 μmol or more, more preferably to use a catalyst so that the amount of metal in the catalyst is 0.3 μmol or more, and it is more preferable to use a catalyst so that the amount of metal in the catalyst is 0.1 μmol or more. It is more preferable to use the catalyst in an amount of 5 μmol or more. Further, the upper limit of the amount of metal in the catalyst is preferably 20 μmol, more preferably 10 μmol, even more preferably 5 μmol, and even more preferably 3 μmol.

If the amount of catalyst is too small, the polymerization rate will be slow, and in order to obtain a polycarbonate resin with a desired molecular weight, the polymerization temperature must be increased accordingly. Therefore, there is a high possibility that the hue of the obtained polycarbonate resin will deteriorate, and unreacted raw materials will volatilize during polymerization, causing the molar ratio of dihydroxy compound and carbonic acid diester to collapse, making it possible that the desired molecular weight will not be reached. There is sex. By setting the catalyst amount to the above lower limit or more, the hue is further improved and it becomes easier to reach the desired molecular weight. On the other hand, if the amount of polymerization catalyst used is too large, undesirable side reactions may occur, resulting in deterioration of the hue of the resulting polycarbonate resin or coloring of the resin during molding. By controlling the amount of catalyst to be less than or equal to the above upper limit, the hue can be further improved and coloration during molding can be further prevented.

However, among the Group 1 metals, sodium, potassium, and cesium may have a negative effect on the hue if they are contained in large amounts in the polycarbonate resin. These metals may be introduced not only from the catalyst used but also from raw materials or reaction equipment. From the viewpoint of further improving the hue, the total amount of these metal compounds in the polycarbonate resin, regardless of the source, is preferably 1 ppm by weight or less, and 0.5 ppm by weight or less as a metal amount. is more preferable.

<Production method of polycarbonate resin>
The polycarbonate resin is obtained by polycondensing at least dihydroxy compound A and carbonic acid diester by transesterification. In the transesterification reaction, dihydroxy compound B and/or dihydroxy compound C, which are selective components, can also be further used as the dihydroxy compound.
It is preferable that the dihydroxy compound and diester carbonate, which are raw materials, are uniformly mixed before the transesterification reaction. If the temperature during mixing is too low, the dissolution rate will be slow and the solubility may be insufficient, often leading to problems such as solidification. On the other hand, if the temperature at the time of mixing is too high, it may cause thermal deterioration of the dihydroxy compound, which may adversely affect the hue and thermal stability of the polycarbonate resin. From the viewpoint of preventing problems such as solidification, the temperature during mixing is usually 80°C or higher, preferably 90°C or higher. From the viewpoint of further improving hue and thermal stability, the temperature during mixing is usually 250°C or lower, preferably 200°C or lower, and more preferably 150°C or lower. The temperature during mixing is particularly preferably 100°C or more and 120°C or less.

From the viewpoint of preventing hue deterioration, the operation of mixing the dihydroxy compound and diester carbonate is preferably carried out in an atmosphere with an oxygen concentration of 10 vol% or less, and more preferably in an atmosphere with an oxygen concentration of 0.0001 vol% to 10 vol%. It is more preferable to carry out the reaction in an atmosphere of % to 5 vol %, and even more preferably to carry out in an atmosphere of 0.0001 vol % to 1 vol %.

The amount of diester carbonate to be used relative to all dihydroxy compounds is preferably 0.90 to 1.20 in molar ratio, more preferably 0.95 to 1.10. In this case, the increase in terminal hydroxyl groups in the polycarbonate resin is suppressed, the thermal stability of the polymer is further improved, and coloring during molding is further suppressed.

Furthermore, when the molar ratio of diester carbonate to all dihydroxy compounds becomes large, the rate of transesterification reaction decreases, and it may become difficult to produce a polycarbonate resin having a desired molecular weight. By controlling the amount of diester carbonate within the above range, the transesterification reaction rate becomes sufficiently high, and a polycarbonate resin having a desired molecular weight can be easily obtained. Furthermore, an increase in thermal history during the polymerization reaction is prevented, and the hue and weather resistance of the resulting polycarbonate resin are further improved. Furthermore, when the molar ratio of diester carbonate to all dihydroxy compounds increases, the amount of diester carbonate remaining in the resulting polycarbonate resin increases, which may lead to problems with staining and odor during molding. By controlling the amount of diester carbonate within the above range, it is possible to prevent stains and odors from occurring during molding.

The polycondensation reaction between a dihydroxy compound and a carbonic acid diester is usually carried out in multiple stages using a plurality of reactors in the presence of the above-mentioned catalyst. The reaction may be carried out in batch mode, continuous mode, or a combination of batch mode and continuous mode, but from the viewpoints that polycarbonate resin can be obtained with less heat history and is superior in productivity, continuous mode is preferred. Formula is preferred.
In the early stage of polymerization, it is preferable to obtain a prepolymer at a relatively low temperature and low vacuum, and in the late stage of polymerization, it is preferable to increase the molecular weight to a predetermined value at a relatively high temperature and high vacuum. It is preferable to appropriately select the internal temperature and the pressure within the reaction system. In this case, the polymerization rate can be controlled and the quality of the polycarbonate resin can be further improved. For example, if either the temperature or pressure is changed too quickly before the polymerization reaction reaches a predetermined value (specifically, molecular weight), unreacted monomers will distill out and the molar amount of dihydroxy compound and carbonic diester will be reduced. This may upset the ratio, leading to a decrease in the polymerization rate, or making it impossible to obtain a polymer with a predetermined molecular weight or terminal group.

Furthermore, in order to suppress the amount of monomer distilled out, it is effective to use a reflux condenser in the polymerization reactor, and this effect is particularly great in the reactor at the initial stage of polymerization, where there are many unreacted monomer components.
The temperature of the refrigerant introduced into the reflux condenser can be selected appropriately depending on the monomer used, but usually the temperature of the refrigerant introduced into the reflux condenser is 45 to 180°C at the inlet of the reflux condenser. The temperature is preferably 80 to 150°C, particularly preferably 100 to 130°C. If the temperature of the refrigerant is too high, the amount of reflux decreases and the effect is lowered, and if the temperature is too low, the efficiency of distilling off the monohydroxy compound that should originally be distilled off tends to decrease. As the refrigerant, hot water, steam, heat medium oil, etc. are used, and steam and heat medium oil are preferable.

It is preferable to appropriately select the type and amount of the catalyst described above from the viewpoint of maintaining the polymerization rate appropriately, suppressing monomer distillation, and not impairing the hue of the final polycarbonate resin. . The polycarbonate resin is preferably produced by polymerization in multiple stages in multiple reactors using a catalyst. The reason why polymerization is carried out in multiple reactors is that at the beginning of the polymerization reaction, there are many monomers contained in the reaction solution, so it is preferable to maintain the necessary polymerization rate and suppress the volatilization of monomers. This is because in the latter stage of the reaction, it is preferable to sufficiently distill off the by-product monohydroxy compound in order to shift the equilibrium toward the polymerization side. In this way, in order to set different polymerization reaction conditions, it is preferable to use a plurality of polymerization reactors arranged in series from the viewpoint of production efficiency.

As mentioned above, the number of reactors used in the production of polycarbonate resin may be at least two or more, but from the viewpoint of production efficiency, it is preferable to use three or more reactors, preferably three to five, and particularly preferably four. It is. In the present invention, if there are two or more reactors, a plurality of reaction stages with different conditions may be provided in the reactor, or the temperature and pressure may be continuously changed.

The polymerization catalyst can be added to the raw material preparation tank, raw material storage tank, or directly to the polymerization tank, but from the viewpoint of supply stability and polymerization control, it is recommended to add it to the raw material line before being supplied to the polymerization tank. A catalyst supply line is installed in the middle of the catalyst, and preferably an aqueous solution is supplied.

If the temperature of the polymerization reaction is too low, it will reduce productivity and increase the thermal history of the product, and if it is too high, it will not only cause volatilization of the monomer, but also may promote decomposition and coloration of the polycarbonate resin. Specifically, in the first stage reaction, the maximum internal temperature of the polymerization reactor is 130 to 250°C, preferably 150 to 240°C, more preferably 170 to 230°C, and 1 to 110 kPa, preferably is carried out under a pressure of 5 to 70 kPa, more preferably 7 to 30 kPa (absolute pressure), for 0.1 to 10 hours, preferably 0.5 to 3 hours, while distilling the generated monohydroxy compound out of the reaction system. be done.

In the second and subsequent stages, the pressure of the reaction system is gradually lowered from the pressure of the first stage, and while the monohydroxy compound that is subsequently generated is removed from the reaction system, the pressure (absolute pressure) of the reaction system is finally lowered. 200 Pa or less, the maximum internal temperature is 210 to 270°C, preferably 220 to 250°C, particularly preferably 210 to 230°C, usually for 0.1 to 10 hours, preferably 1 to 6 hours, particularly preferably 0. . Do this for 5 to 3 hours.
If the polymerization temperature is too high and the polymerization time is too long in order to obtain a polycarbonate resin with a predetermined molecular weight, the color tone tends to deteriorate. In particular, in order to suppress coloring and thermal deterioration of the polycarbonate resin and obtain a polycarbonate resin with a good hue, it is preferable that the maximum internal temperature in all reaction steps is less than 250°C, particularly 220 to 245°C. In addition, in order to prevent a decrease in the polymerization rate in the latter half of the polymerization reaction and to minimize deterioration due to thermal history, it is recommended to use a horizontal reactor with excellent plug flow and interface renewability in the final stage of polymerization. preferable.

From the viewpoint of effective resource utilization, the by-produced monohydroxy compound is preferably purified as necessary and then reused as a raw material for diphenyl carbonate, bisphenol A, and the like.
After polycondensation as described above, the polycarbonate resin is usually cooled and solidified, and pelletized using a rotary cutter or the like. The method of pelletizing is not limited, but it can be extracted from the final polymerization reactor in a molten state, cooled and solidified in the form of a strand, and then pelletized, or uniaxial or twin-screw extrusion in the molten state from the final polymerization reactor. The resin is supplied to the machine, melted and extruded, then cooled and solidified to form pellets. Alternatively, the resin is extracted from the final polymerization reactor in a molten state, cooled and solidified in the form of a strand, once pelletized, and then re-uniaxially extruded. Alternatively, the resin may be supplied to a twin-screw extruder, melted and extruded, and then cooled and solidified to form pellets.

When an extruder is used, residual monomers are devolatilized under reduced pressure, and commonly known heat stabilizers, neutralizing agents, ultraviolet absorbers, light stabilizers, mold release agents, colorants, and antistatic agents are used. , a lubricant, a plasticizer, a compatibilizer, a flame retardant, etc. can also be added and kneaded.
The melt-kneading temperature in the extruder depends on the glass transition temperature and molecular weight of the polycarbonate resin, but is preferably 200 to 300°C. In this case, the load on the extruder is reduced and productivity is improved. Furthermore, in this case, thermal deterioration is reduced, mechanical strength is further improved, coloring of the resin is further suppressed, and gas generation is further prevented. From the viewpoint of further improving these effects, the melt-kneading temperature in the extruder is more preferably 210 to 280°C, and even more preferably 220 to 270°C.

The molecular weight of polycarbonate resin can be expressed in terms of reduced viscosity. From the viewpoint of further improving the mechanical strength of the molded article, the reduced viscosity of the polycarbonate resin is preferably 0.30 dL/g or more, more preferably 0.35 dL/g or more. From the viewpoint of improving fluidity during molding and improving productivity and moldability, the reduced viscosity of the polycarbonate resin is preferably 1.20 dL/g or less, and 1.00 dL/g or less. is more preferable, and even more preferably 0.80 dL/g or less. The reduced viscosity of the polycarbonate resin was measured using an Ubbelohde viscosity tube at a temperature of 20.0°C ± 0.1°C using methylene chloride as a solvent and precisely adjusting the polycarbonate resin concentration to 0.6 g/dL. Ru. The reduced viscosity of the polycarbonate resin can be adjusted within the above range by adjusting the molecular weight and composition ratio, for example.

This improves the toughness of polycarbonate resin and further improves mechanical properties, improves fluidity during molding, improves the appearance of molded products, improves dimensional accuracy, and improves resin temperature due to shear heat generation. From the viewpoint of suppressing the increase and further preventing resin coloring and foaming, the melt viscosity of the polycarbonate resin is preferably 300 to 3000 Pa·s, more preferably 400 to 2800 Pa·s, and 500 Pa·s. More preferably, it is from s to 2500 Pa·s. In this specification, the melt viscosity refers to the melt viscosity at a measurement temperature of 240° C. and a shear rate of 91.2 sec ⁻¹ using a capillary rheometer [manufactured by Toyo Seiki Co., Ltd.]. The melt viscosity of the polycarbonate resin can be adjusted within the above range by, for example, adjusting the molecular weight and composition ratio.

From the perspective of further suppressing the deformation of molded products under high temperature and high humidity conditions and improving heat resistance, it prevents the temperature from becoming excessively high during molding processing, and reduces the molecular weight reduction and coloring of polycarbonate resin during molding processing. The glass transition temperature of the polycarbonate resin is preferably 80°C or higher and 180°C or lower, and preferably 90°C or higher, from the viewpoint of further preventing thermal deterioration such as heat deterioration, and preventing poor appearance of molded products due to gas generation. , more preferably 160°C or lower, and still more preferably 95°C or higher and 140°C or lower. Note that the glass transition temperature of the polycarbonate resin is measured using a differential scanning calorimeter (DSC). The glass transition temperature of the polycarbonate resin can be adjusted within the above range, for example, by adjusting the blending ratio of dihydroxy compound A in all dihydroxy compounds.

<Silica particles>
Preferably, the silica particles are composed of amorphous silica. Amorphous silica refers to silica in which the molecules that make up the silica structure do not form a regular crystal lattice. The silica particles may be surface-treated with a hydrophobic silane coupling agent or may not be surface-treated. Hydrophobic silane coupling agents (hereinafter appropriately referred to as "surface treatment agents") are those that can react with hydrophobic functional groups such as alkyl groups and aryl groups and hydrophilic groups such as silanol groups on the surface of silica particles. It has a hydrolyzable functional group that generates a group.

A typical example of the hydrophobic silane coupling agent is represented by the following formula (5).
R ¹ -Si-(R ² ) _n ...(5)
In formula (5), R ¹ is an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 1 to 30 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and R ² is a hydrolyzable group. , n represents an integer from 1 to 3. The surface of the silica particles is preferably composed of silica modified with an alkyl group having 1 to 30 carbon atoms, silica modified with an alkenyl group having 1 to 30 carbon atoms, or silica modified with an aryl group having 6 to 12 carbon atoms.

Examples of R ² in the above formula (5) include a halogen group such as a chloro group, an alkoxy group having 1 to 12 carbon atoms, an amino group having 1 to 12 carbon atoms, and the most common is an alkoxy group. preferable. From the viewpoint of hydrolyzability and ease of synthesis, the alkoxy group is preferably a lower alkoxy group having 4 or less carbon atoms, and more preferably a methoxy group, an ethoxy group, or a propoxy group.

Further, R ¹ in formula (5) is a hydrophobic group, and examples of R ¹ include an alkyl group and an aryl group. Examples of alkyl groups include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, octyl group, decyl group, dodecyl group, hexadecyl group, octadecyl group, etc., and these groups have a cyclic structure. or may have a branched structure. Examples of the alkyl group having a cyclic structure include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Examples of the alkyl group having a branched structure include an alkyl group having at least one side chain, such as a tertiary butyl group, an isobutyl group, and an isopropyl group. Examples of alkenyl groups include vinyl, allyl, and butenyl groups, and examples of aryl groups include phenyl and naphthyl groups.

Examples of surface treatment agents include dimethyldichlorosilane, hexamethyldisilazane, methyltrimethoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, isopropyltrimethoxysilane, n-butyltrimethoxysilane, and isobutyltrimethoxysilane. , pentyltrimethoxysilane, n-hexyltrimethoxysilane, n-octyltrimethoxysilane, isooctyltrimethoxysilane, n-decyltrimethoxysilane, dodecyltrimethoxysilane, hexadecyltrimethoxysilane, n-octadecyltrimethoxysilane , styrylethyltrimethoxysilane, phenethyltrimethoxysilane, cyclohexyltrimethoxysilane, cyclopentyltrimethoxysilane, phenyltrimethoxysilane, benzyltrimethoxysilane, 3-(pentafluorophenyl)propyltrimethoxysilane, (3,3,3 -trifluoropropyl)trimethoxysilane, chlorophenyltrimethoxysilane, (chloromethyl)phenylethyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3-bromopropyltrimethoxysilane, 3-iodopropyltrimethoxysilane, vinyltrimethoxysilane Particularly preferred are methoxysilane, allyltrimethoxysilane, dimethylpolysiloxane, and the like.

Silica particles have extremely fine particle sizes on the nano-order, and their average primary particle size is less than 100 nm. Preferably, the average primary particle diameter of the silica particles is 1 nm or more. The average primary particle diameter of the silica particles is more preferably 1 to 50 nm, even more preferably 5 to 30 nm, even more preferably 5 to 20 nm, and particularly preferably 5 to 15 nm. Preferably, the silica particles are substantially non-agglomerated. As a result, when blended with polycarbonate resin, nano-order silica particles are dispersed in the resin, making it possible to improve mechanical properties such as surface hardness and strength without impairing transparency or heat resistance. Furthermore, in the field of films and sheets, anti-blocking properties (that is, slip properties) can be improved.

<Method for measuring average primary particle diameter of silica particles>
The average primary particle diameter of silica particles is measured by the BET method. Specifically, the specific surface area of the silica particles is measured using an automatic specific surface area measuring device, and the average primary particle diameter is calculated based on the following formula (I).
Average primary particle diameter (nm) = 6000/(specific surface area (m ² /g) x density (g/cm ³ ))...(I)

From the viewpoint of improving mechanical properties, the content of silica particles relative to 100 parts by weight of the polycarbonate resin composition is preferably 0.1 to 10 parts by weight, more preferably 0.5 to 10 parts by weight, and 1 to 10 parts by weight. It is more preferably from 1 to 10 parts by weight, even more preferably from 1 to 5 parts by weight, and particularly preferably from 1 to 3 parts by weight. In this case, the effect of improving scratch resistance and heat resistance is fully exhibited, and the distance between silica particles is maintained sufficiently to suppress aggregation of silica particles, thereby further improving transparency.

In addition, from the viewpoint of improving blocking resistance (that is, slipperiness) in the field of films and sheets, the content of silica particles with respect to 100 parts by weight of the polycarbonate resin composition is preferably 0.01 parts by weight or more, and 0.01 parts by weight or more. The amount is more preferably 0.03 parts by weight or more, and even more preferably 0.05 parts by weight or more. On the other hand, from the viewpoint of transparency, the amount is preferably 0.45 parts by weight or less, more preferably 0.33 parts by weight or less, and even more preferably 0.2 parts by weight or less. In this case as well, the effect of improving blocking resistance (that is, slipperiness) is fully exhibited, and the distance between silica particles is maintained sufficiently to suppress agglomeration of silica particles, further improving transparency. .

<Dispersant>
A dispersant can be added to the polycarbonate resin composition as needed. In this case, aggregation of silica particles is suppressed, and nano-order silica particles are easily dispersed in the polycarbonate resin. The blending amount of the dispersant is preferably 0.1 to 40 parts by weight, more preferably 0.5 to 30 parts by weight, and 0.5 to 20 parts by weight based on 100 parts by weight of silica. It is even more preferable.

The dispersant may be one that prevents agglomeration of silica particles contained in the polycarbonate resin composition (that is, a silica dispersant), such as DISPERLAST-1018, DISPERLAST-1142, DISPERLAST-1150 manufactured by Bikkemie Japan. , DISPERBYK-192, BYK-9076, BYK-P-4100, BYK-P-4102, etc. can be used.

<Additives>
Additives may include antioxidants, ultraviolet absorbers, heat stabilizers, weather stabilizers, antistatic agents, anti-shrinkage agents, mold release agents, lubricants, impact modifiers, as long as they do not impair the effects of the present invention. Agents, plasticizers, flame retardants, preservatives, etc. may be added to the polycarbonate resin composition as appropriate.

<Polycarbonate resin composition>
The polycarbonate resin composition contains a polycarbonate resin and silica having an average primary particle size of less than 100 nm.

<Glass transition temperature of polycarbonate resin composition>
The glass transition temperature of the polycarbonate resin composition is preferably 80°C or higher and 180°C or lower, more preferably 90°C or higher and 160°C or lower, and preferably 95°C or higher and 140°C or lower. More preferred. In this case, deformation of the molded product under high temperature and high humidity conditions is further suppressed, and heat resistance is further improved. Moreover, in this case, the temperature during molding can be prevented from becoming excessively high, and thermal deterioration such as molecular weight reduction and coloring of the polycarbonate resin composition during molding can be further prevented. Furthermore, in this case, it is possible to prevent the appearance of the molded product from deteriorating due to the generation of gas. Note that the glass transition temperature of the polycarbonate resin composition is measured using a differential scanning calorimeter (DSC). Details of the measurement conditions are described in the Examples section. The glass transition temperature of the polycarbonate resin composition can be adjusted within the above range, for example, by adjusting the blending ratio of dihydroxy compound A in all dihydroxy compounds constituting the polycarbonate resin composition.

<Haze of polycarbonate resin composition>
The haze of the polycarbonate resin composition is preferably 40% or less, more preferably 20% or less, and even more preferably 10% or less. Note that a method for measuring Haze of a polycarbonate resin composition will be explained in Examples. Haze of a polycarbonate resin composition can be determined by, for example, the blending ratio of dihydroxy compound A in all dihydroxy compounds constituting the polycarbonate resin composition, the blending ratio of silica particles, and the blending ratio of a dispersant for silica particles that is selectively added. By adjusting, it is possible to adjust to the above range.

<Kneading method>
When kneading polycarbonate resin and silica using an extruder, either blend them in advance and feed them from a raw material hopper and melt-knead them, or alternatively, feed the polycarbonate resin from the raw material hopper and add silica from a side feeder. A polycarbonate resin composition can be obtained by melt-kneading the mixture. The polycarbonate resin composition can be cooled and solidified in the form of a strand to be pelletized. The melt-kneading temperature in the extruder depends on the glass transition temperature and molecular weight of the polycarbonate resin composition, but is usually 200 to 300°C, preferably 210 to 280°C, more preferably 220 to 270°C. By setting the melt-kneading temperature within the above range, the melt viscosity of the polycarbonate resin composition is reduced, the load on the extruder is reduced, and productivity is improved. In addition, by keeping the melt-kneading temperature within the above range, thermal deterioration of the polycarbonate resin composition is further suppressed, the molecular weight becomes sufficiently high, mechanical strength is further improved, and coloration and gas generation are further suppressed. Ru.

<Method for molding polycarbonate resin composition>
The polycarbonate resin composition can be molded by commonly known methods such as injection molding, extrusion molding, and compression molding. A molded article made of a polycarbonate resin composition has excellent scratch resistance and blocking resistance while maintaining transparency and heat resistance. Furthermore, the molded product can also have excellent mechanical strength while maintaining its hue, transparency, heat resistance, weather resistance, and the like.

<Applications of polycarbonate resin composition>
Because molded bodies of polycarbonate resin compositions have the above characteristics, they can be used in the fields of injection molding, films, and sheets, including automotive parts, electrical and electronic parts, and glass replacement applications, which require even higher specifications than conventional ones. is expected to be applied. In addition, in the field of bottles and containers; lens applications such as camera lenses, finder lenses, CCD lenses, and CMOS lenses; optical materials such as light diffusion sheets; optical components such as optical discs; binders that immobilize dyes and charge transfer agents, etc. It is also expected to be applied to other uses.

EXAMPLES The present invention will be described in more detail by way of Examples below, but the present invention is not limited by the Examples unless the gist thereof is exceeded.

[Evaluation method]
In the following, the physical properties and characteristics of the polycarbonate resin and polycarbonate resin composition were evaluated by the following method.

(1) Test piece preparation method Pellets of the polycarbonate resin composition were dried at 105° C. for 20 hours in the atmosphere. Next, the dried pellets were supplied to an injection molding machine (small injection molding machine C.Mobile-0813 manufactured by Shinko Selbic Co., Ltd.), and an injection molded plate (width 13 mm x length 53 mm x thickness 3 mm). This injection molded plate was used as a test piece.

(2) Test film production method Pellets of the polycarbonate resin composition were dried at 105° C. for 20 hours under vacuum. Next, the dried pellets were pressed using a heat press machine (Mini Test Press machine manufactured by Toyo Seiki Co., Ltd.) at a resin temperature of 220°C to produce a film of 100 mm square and 100 μm thick. This film is used as the test film.

(3) Glass transition temperature The glass transition temperature was measured using a differential scanning calorimeter (DSC6220 manufactured by SII Nanotechnology). Specifically, first, approximately 10 mg of a polycarbonate resin composition sample was placed in an aluminum pan made by the same company and sealed, and the aluminum pan was heated from room temperature to 200 °C at a temperature increase rate of 20 °C/min under a nitrogen flow of 50 mL/min. The temperature was raised. After maintaining the temperature at 200°C for 3 minutes, it was cooled to 30°C at a rate of 20°C/min. The temperature was maintained at 30°C for 3 minutes, and then the temperature was raised again to 200°C at a rate of 20°C/min. From the DSC data obtained during the second temperature increase, we found a straight line extending the baseline on the low temperature side to the high temperature side, and a tangent line drawn at the point where the slope of the curve of the step-like change part of the glass transition is maximum. The extrapolated glass transition start temperature, which is the temperature at the intersection of , was determined and used as the glass transition temperature.
[Judgment criteria]
The case where the glass transition temperature was 119°C or more and 140°C or less was evaluated as "○", and the case where it was less than 119.0°C was evaluated as "x". Note that cases where the temperature exceeded 140.0°C were also evaluated as "x".

(4) Scratch resistance The scratch resistance of the test piece obtained in (1) above was measured using an abrasion tester (Daei Scientific It was measured using a plane abrasion tester PA-300A (manufactured by Seiki Seisakusho). Specifically, a test piece was set at the measurement position of an abrasion tester, an abrasive material was slid on the surface of the test piece, and the degree of damage on the surface of the test piece was visually observed and evaluated. Tissue (Nippon Paper Industries Scotty Cresia folded into three) and work gloves were used as wear materials. Note that the conditions of the wear tester are as follows.
Stroke: 2.0cm
Number of wear: 500 times Sliding speed: 50 strokes/min
Load: 1kg
In addition, the scratch resistance was visually evaluated using the following five-level criteria.
[Judgment criteria]
1: Scratches are clearly visible throughout the stroke width.
2: Although it is about 1/2 of the stroke width, the scratch is clearly visible.
3: Slight scratches can be seen throughout the stroke width.
4: A slight scratch can be seen at about 1/2 of the stroke width.
5: No scratches at all.

(5) Haze
Haze (%) was measured using a color/turbidity simultaneous measuring device COH-400 (Nippon Denshoku Industries Co., Ltd.) using the test piece of (1) above and the test film of (2) above.
In this example, from the viewpoint of practicality, 40% or less of the test piece was considered to be excellent in haze, and 5% or less of the test film was considered to be excellent in haze.

(6) Film blocking resistance (i.e. slipperiness)
Two test films from (2) above were stacked and pinched between the thumb and forefinger as if the load was about 200 g, and the slippage was evaluated when the films were shifted by 2 cm.
In addition, the slipperiness was evaluated using the following three-level criteria.
1: No slipping at all.
2: I slipped about 1cm.
3: I slipped 2cm.

[silica]
The following silica was used in the polycarbonate resin composition.
・Silica 1 AEROSIL 300CF (untreated silica) manufactured by Nippon Aerosil Co., Ltd. Average primary particle size: 10 nm
・Silica 2 AEROSIL R805 (octyl group modified silica) manufactured by Nippon Aerosil Co., Ltd. Average primary particle diameter: 12 nm
・Silica 3 Admatex YA010C-SP3 (phenyl group modified silica) Average primary particle size: 10 nm
・Silica 4 AEROSIL R976S (dimethyl silica) manufactured by Nippon Aerosil Co., Ltd. Average primary particle size: 7 nm
・Silica 5 AEROSIL RX300 (trimethyl silica) manufactured by Nippon Aerosil Co., Ltd. Average primary particle size: 7 nm
・Silica 6 Admatex S0-C1 (untreated silica) Average primary particle size: 300 nm
・Silica 7 Admatex S0-C6 (untreated silica) Average primary particle diameter: 2000 nm
・Silica 8 Manufactured by Admatex FEF75H (untreated silica) Average primary particle diameter: 24300 nm
・Silica 9 Admatex S0-C2 (untreated silica) Average primary particle size: 500 nm

[Dispersant]
The following silica dispersants were used in the polycarbonate resin composition.
・Dispersant (1) BYK-P-4102 manufactured by BYK Chemie Japan Co., Ltd.
・Dispersant (2) DISPERPLAST-1018 manufactured by BIC Chemie Japan Co., Ltd.

[Production Example 1: Production of polycarbonate resin]
Isosorbide (i.e., ISB) and 1,4-cyclohexanedimethanol (i.e., CHDM) were added to a polymerization reactor equipped with a stirring blade and a reflux condenser controlled at 100°C, and the chloride ion concentration was reduced to 10 ppb or less by distillation purification. diphenyl carbonate (i.e., DPC) and calcium acetate monohydrate in a molar ratio of ISB/CHDM/DPC/calcium acetate monohydrate = 0.7/0.3/1.00/1.3× The mixture was charged to a concentration of 10 ^-6 and sufficiently replaced with nitrogen (oxygen concentration 0.0005% to 0.001% by volume). Subsequently, the contents were heated using a heating medium. Stirring was started when the internal temperature reached 100°C, and while controlling the internal temperature to 100°C, the contents were melted and the raw material preparation liquid was made uniform. Thereafter, temperature increase was started, and the internal temperature was brought to 210° C. over 40 minutes. When the internal temperature reaches 210°C, control is performed to maintain this temperature, and pressure reduction is started, and after reaching 210°C, the pressure is increased to 13.3 kPa (absolute pressure, the same applies hereinafter) over 90 minutes. This pressure was then maintained for an additional 60 minutes. Phenol vapor produced as a by-product during the polymerization reaction was led to a reflux condenser. The components condensed in the reflux condenser were returned to the polymerization reactor, and the uncondensed phenol vapor was subsequently led to a condenser using 45° C. hot water as a refrigerant and recovered.

After the contents oligomerized in the above polymerization reactor were once restored to atmospheric pressure, they were transferred to another polymerization reactor equipped with a stirring blade and a reflux condenser controlled in the same manner as above, and then heated and Depressurization was started, and the internal temperature was adjusted to 220° C. and the pressure to 200 Pa over 60 minutes. Thereafter, the internal temperature was adjusted to 228° C. and the pressure to 133 Pa or less over 20 minutes, and when the predetermined stirring power was reached, the pressure was restored to obtain a polycarbonate copolymer in a molten state from the exit of the polymerization reactor.
Further, the molten polycarbonate copolymer was continuously fed into a twin screw extruder equipped with three vent ports and water injection equipment, and Irganox 1010 (as an antioxidant) was added to 100 parts by weight of the polycarbonate copolymer. BASF Japan Co., Ltd., pentaerythritol-tetrakis [3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]) 0.1 part by weight, ADEKA STAB 2112 (ADEKA Co., Ltd., tris(2) , 4-di-tert-butylphenyl) phosphite) and 0.3 parts by weight of Unistar E-275 (manufactured by NOF Corporation) as a mold release agent were added continuously, and the mixture was subjected to twin-screw extrusion. After low molecular weight substances such as phenol were devolatilized under reduced pressure at each vent section provided in the machine, pelletization was performed using a pelletizer to obtain a polycarbonate resin.

[Production Example 2: Production of polycarbonate resin]
A polycarbonate resin was obtained in the same manner as Production Example 1 except that CHDM was changed to tricyclodecane dimethanol (ie, TCDDM) and that Adekastab 2112 and Unistar E-275 were not used.

[Example 1]
Using 97.6 parts by weight of the polycarbonate resin obtained in Production Example 1, 2.0 parts by weight of Silica 1 (AEROSIL300CF manufactured by Nippon Aerosil Co., Ltd.) as silica, and 0.4 parts by weight of dispersant (1) as a silica dispersant. , these were blended in advance, and using a twin-screw kneader (manufactured by Japan Steel Works, TEX30SST42BW: screw diameter 30 mm, L/D = 42), the cylinder temperature was 240°C, the screw rotation speed was 200 rpm, and the discharge amount was 12 kg/ The resin composition sample was extruded into a strand using a strand cutter to obtain a resin composition sample in the form of pellets.
The obtained pellet-like samples were evaluated according to the evaluation methods (1), (3) to (5) described above, and the results are shown in Table 1.

[Example 2]
A pellet sample was obtained in the same manner as in Example 1 except that 0.4 parts by weight of dispersant (2) was used as the silica dispersant. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

[Example 3]
A pellet sample was obtained in the same manner as in Example 1 except that Silica 2 (AEROSILR805, manufactured by Nippon Aerosil Co., Ltd.) was used as the silica. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

[Example 4]
A pellet sample was obtained in the same manner as in Example 2, except that Silica 2 (AEROSILR805, manufactured by Nippon Aerosil Co., Ltd.) was used as the silica. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

[Example 5]
A pellet sample was obtained in the same manner as in Example 1, except that Silica 3 (YA010C-SP3, manufactured by Admatex) was used as the silica. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

[Example 6]
A pellet sample was obtained in the same manner as in Example 2, except that Silica 3 (YA010C-SP3, manufactured by Admatex) was used as the silica. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

[Example 7]
A pellet sample was prepared in the same manner as in Example 1, except that 99.0 parts by weight of polycarbonate resin, 1.0 parts by weight of silica 4 (AEROSILR976S, manufactured by Nippon Aerosil Co., Ltd.) was used as silica, and no dispersant was used. I got it. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

[Example 8]
A pellet sample was obtained in the same manner as in Example 7 except that Silica 5 (AEROSIL RX300, manufactured by Nippon Aerosil Co., Ltd.) was used as the silica. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 1.

[Example 9]
A pellet sample was prepared in the same manner as in Example 1, except that 99.9 parts by weight of the polycarbonate resin obtained in Production Example 2 and 0.1 part by weight of Silica 1 (AEROSIL 300CF, manufactured by Nippon Aerosil Co., Ltd.) were used as the silica. Obtained. The pellet samples were evaluated according to the evaluation methods (1) to (6) described above, and the results are shown in Table 1.

[Comparative example 1]
A pellet sample was obtained in the same manner as in Example 1 except that silica was not used. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[Comparative example 2]
A pellet sample was obtained in the same manner as in Example 2 except that silica was not used. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[Comparative example 3]
A pellet sample was obtained in the same manner as in Example 1 except that silica and dispersant (1) were not used (that is, 100 parts by weight of polycarbonate resin was used). The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[Comparative example 4]
A pellet sample was obtained in the same manner as in Example 1 except that silica 6 (S0-C1, manufactured by Admatex) was used as the silica. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[Comparative example 5]
A pellet sample was obtained in the same manner as in Comparative Example 4 except that 0.4 parts by weight of dispersant (2) was used as the silica dispersant. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[Comparative example 6]
A pellet sample was obtained in the same manner as in Example 1, except that Silica 7 (S0-C6, manufactured by Admatex) was used as the silica. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[Comparative Example 7]
A pellet sample was obtained in the same manner as in Comparative Example 6 except that 0.4 parts by weight of dispersant (2) was used as the silica dispersant. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[Comparative example 8]
A pellet sample was obtained in the same manner as in Example 1 except that Silica 8 (FEF75H manufactured by Admatex) was used as the silica. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[Comparative Example 9]
A pellet sample was obtained in the same manner as in Comparative Example 8 except that 0.4 parts by weight of dispersant (2) was used as the silica dispersant. The pelleted sample was evaluated in the same manner as in Example 1, and the results are shown in Table 2.

[Comparative Example 10]
A pellet sample was obtained in the same manner as in Example 9 except that 100 parts by weight of polycarbonate resin was used without using silica. The pelleted sample was evaluated in the same manner as in Example 9, and the results are shown in Table 2.

[Comparative Example 11]
A pellet sample was obtained in the same manner as in Example 9, except that 0.1 part by weight of Silica 9 (S0-C2, manufactured by Admatex) was used as the silica. The pelleted sample was evaluated in the same manner as in Example 9, and the results are shown in Table 2.

As understood from Tables 1 and 2, the polycarbonate resin composition ( It can be seen that Examples 1 to 9) have improved scratch resistance compared to Comparative Examples 1 to 3 and 10, and improved transparency compared to Comparative Examples 4 to 9 and 11. Further, the above-mentioned specific polycarbonate resin compositions (see Examples 1 to 9) have excellent transparency without reducing heat resistance. In other words, it has excellent transparency, heat resistance, and scratch resistance. Moreover, the polycarbonate resin composition of Example 9 has good slipperiness in a film state and is also excellent in blocking resistance. In addition, as in Example 9, when the polycarbonate resin has a structural unit derived from TCDDM as well as a structural unit derived from ISB, the heat resistance is further improved, so it can be used in the film/sheet field where heat resistance is required, and in optical materials. , it becomes more suitable for applications such as optical parts.

Claims (6)

A polycarbonate resin containing at least a structural unit A derived from a dihydroxy compound represented by the following formula (1),
A polycarbonate resin composition containing silica particles having an average primary particle diameter of less than 100 nm.

The polycarbonate resin according to claim 1, wherein the weight fraction of the structural unit A is 10% by weight or more and 90% by weight or less with respect to 100% by weight of structural units derived from all dihydroxy compounds constituting the polycarbonate resin. Composition. The polycarbonate resin composition according to claim 1 or 2, wherein the silica particles are composed of amorphous silica. The polycarbonate resin composition according to claim 1 or 2, wherein the content of the silica particles is 0.1 parts by weight or more and 10 parts by weight or less with respect to 100 parts by weight of the polycarbonate resin composition. The polycarbonate resin composition according to claim 1 or 2, wherein the polycarbonate resin composition contains a dispersant. A molded article made of the polycarbonate resin composition according to claim 1 or 2.