Organic-inorganic composites

Abstract

To provide an organic-inorganic composite composition that includes inorganic fine particles uniformly dispersed in polycarbonate resin, wherein the composition can be practically used as an optical resin even after molding.SOLUTION: An organic-inorganic composite composition includes a polycarbonate resin having a structural unit of formula (1) at a polymer chain end, and inorganic fine particles. The inorganic fine particles are at least one selected from the group consisting of ZrO2 (zirconium oxide), TiO2 (titanium oxide), SnO2 (tin oxide), SiO2 (silicon oxide), and Al2O3 (aluminum oxide).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an organic-inorganic hybrid composition containing a polycarbonate resin and inorganic fine particles. [Background technology]

[0002] In recent years, the development of optical materials has been actively pursued. For example, in the field of optical lens materials, there is a demand for optical materials that have a high refractive index, a high Abbe number, heat resistance, and excellent transparency. Conventionally used glass is capable of achieving various required optical properties and has excellent environmental resistance, but suffers from the problem of poor processability. In response to this, resin materials, which are cheaper and more processable than glass materials, have been used in optical components. However, because resins generally have a lower refractive index than glass, the material itself must have a high refractive index in order to thin optical components.

[0003] One method for increasing the refractive index is to uniformly disperse fine particles of inorganic oxides such as titanium oxide and zirconium oxide in a resin. However, since such fine particles have a large surface energy, it is difficult to uniformly disperse them in a matrix resin, and various studies have been conducted to date.

[0004] One method for uniformly dispersing fine particles in a resin involves chemically modifying the surface of the fine particles with a surface modifier. For example, Patent Document 1 describes a method in which fine particles modified with a specific chemical structure are mixed with a resin to prepare a masterbatch, which is then melt-kneaded with a thermoplastic resin to obtain a transparent resin composition. While this method improves dispersibility to some extent by selecting a surface modifier, it is still difficult to say that sufficient dispersibility is achieved. Another problem is that the content of inorganic fine particles is low, which is insufficient in terms of achieving a high refractive index.

[0005] Patent Document 2 describes a method of introducing carboxyl groups to the terminals of a polycarbonate resin after polymerization, and a method of obtaining a carboxyl-containing polycarbonate resin by copolymerizing a diol compound having a carboxyl group, and describes that the resulting film composited with inorganic fine particles has excellent transparency. The method of introducing carboxyl groups to the terminals utilizes the reaction between hydroxyl groups at the polymer terminals and an acid anhydride. Because this method uses a polyfunctional compound as the acid anhydride, gelation may be a problem, especially during processing at high temperatures. Furthermore, in the copolymerization method, the carboxyl groups react with other diol compounds during polymerization, making it difficult to control the amount of carboxyl groups introduced, and the dispersion stability of the inorganic fine particles may be an issue, especially under high-temperature conditions. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-38012 [Patent Document 2] Japanese Patent Application Publication No. 2018-138624 Summary of the Invention [Problem to be solved by the invention]

[0007] Although a method of increasing the refractive index of polycarbonate by designing the molecular structure of the polymer to improve the electron density is commonly used, a method of increasing the refractive index by uniformly dispersing fine particles in the resin is rarely used in practice. This is because, in addition to the difficulty of obtaining a resin composition in which fine particles are uniformly dispersed, even if such a resin composition is obtained, when the resin composition is molded, the dispersion state of the fine particles may change and the fine particles may aggregate.

[0008] Therefore, an object of the present invention is to provide an organic-inorganic composite composition in which inorganic fine particles are sufficiently dispersed in a polycarbonate resin, which can be practically used as an optical resin even after molding. [Means for solving the problem]

[0009] As a result of extensive research, the present inventors have found that the dispersibility of inorganic fine particles in polycarbonate resin can be improved by using a polycarbonate resin having a specific structural unit at the polymer chain terminal, and have demonstrated that an organic-inorganic hybrid composition containing the polycarbonate resin and inorganic fine particles has excellent transparency, moldability, and refractive index, thereby completing the present invention. That is, according to the present invention, the object of the invention is achieved as follows.

[0010] 1. An organic-inorganic hybrid composition comprising a polycarbonate resin containing a structural unit represented by the following formula (1) at the polymer chain terminal, and inorganic fine particles. [ka] (In formula (1), R 1 and R 2 may be independent or the same, and represent at least one group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cycloalkyl group, a cycloalkoxy group, an alkenyl group, an aryl group, an aryloxy group, an aralkyl group, an aralkyloxy group, a nitro group, an aldehyde group, and a cyano group; a and b each represent an integer of 1 to 2; X represents a single bond or a group represented by the following formula (2): [ka] where R is a divalent group represented by 5 represents at least one group selected from the group consisting of an alkylene group, an aralkylene group, an arylene group, and a cycloalkylene group; R 3 and R 4each independently represents at least one group selected from the group consisting of an alkylene group, an aralkylene group, an arylene group, and a cycloalkylene group; R 4 The hydrogen atoms in may be substituted with carboxyl groups. 2. The organic-inorganic hybrid composition according to item 1 above, wherein the molar ratio of the polymer chain ends is 1.0 mol % or more and 10 mol % or less relative to 100 mol % of all carbonate repeating units. 3. The organic-inorganic hybrid composition according to item 1 or 2 above, wherein the formula (1) contains a structural unit represented by the following formula (3): [ka] (In formula (3), R 6 represents at least one group selected from the group consisting of a single bond, an alkylene group, an aralkylene group, an arylene group, and a cycloalkylene group. 4. The organic-inorganic hybrid composition according to item 1 or 2 above, wherein the formula (1) contains a structural unit represented by the following formula (4): [ka] (In formula (4), R 7 represents at least one group selected from the group consisting of an alkylene group, an aralkylene group, an arylene group, and a cycloalkylene group. 5. The organic-inorganic hybrid composition according to any one of items 1 to 4 above, wherein the polycarbonate resin has a carboxyl group amount of 1 eq / ton to 200 eq / ton. 6. The organic-inorganic hybrid composition according to any one of items 1 to 5 above, wherein the surfaces of the inorganic fine particles are modified with a surface modifying agent. 7. The organic-inorganic hybrid composition according to item 6 above, wherein the surface modifier has an acidic functional group. 8. The organic-inorganic hybrid composition according to item 7 above, wherein the acidic functional group is at least one acidic functional group selected from the group consisting of a sulfonic acid group, a phosphonic acid group, a phosphinic acid group, and a carboxylic acid group. 9. The organic-inorganic hybrid composition according to any one of items 6 to 8 above, wherein the surfaces of the inorganic fine particles are modified with the surface modifying agent in an amount of 1 to 30% by mass relative to the inorganic fine particles. 10. The organic-inorganic hybrid composition according to any one of items 1 to 9 above, wherein the inorganic fine particles have an average particle size of 1 to 20 nm. 11. The organic-inorganic hybrid composition according to any one of items 1 to 10 above, wherein the content of the inorganic fine particles is 1 to 50% by mass relative to the polycarbonate resin. 12. The organic-inorganic hybrid composition according to any one of items 1 to 11 above, wherein the inorganic fine particles are at least one selected from the group consisting of ZrO2 (zirconium oxide), TiO2 (titanium oxide), SnO2 (tin oxide), SiO2 (silicon oxide), and Al2O3 (aluminum oxide). 13. A molded article obtained by using the organic-inorganic hybrid composition according to any one of items 1 to 12 above. 14. A film or sheet obtained by using the organic-inorganic hybrid composition according to any one of items 1 to 12 above. [Effects of the Invention]

[0011] According to the present invention, by using a polycarbonate resin having a specific structural unit at a polymer chain terminal and inorganic fine particles, it is possible to provide an organic-inorganic hybrid composition that has improved dispersibility of the inorganic fine particles in the polycarbonate resin and is excellent in transparency, moldability, and refractive index. [Brief explanation of the drawings]

[0012] [Figure 1] The photograph in FIG. 1 shows a TEM image of the organic-inorganic composite composition prepared in Example 1. [Figure 2] The photograph in FIG. 2 shows a TEM image of the organic-inorganic hybrid composition produced in Comparative Example 3. DETAILED DESCRIPTION OF THE INVENTION

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure is not limited to the following embodiments, and various modifications can be made within the scope of the present invention.

[0014] One aspect of the present invention is characterized by using a polycarbonate resin containing a structural unit having a carboxyl group at the polymer chain terminal, as represented by the above formula (1). The organic-inorganic hybrid composition of the present invention has excellent dispersion stability of inorganic fine particles under high temperature conditions, and is excellent in transparency, moldability, and refractive index.

[0015] On the other hand, in the method described in the above Patent Document 2, a polymer having a carboxyl group at the side chain or end is used to produce an organic-inorganic composite composition having excellent transparency. However, according to the investigations of the present inventors, it has become clear that the transparency decreases under high temperature conditions such as injection molding, and decomposition occurs during molding, making it impossible to obtain a molded product.

[0016] Although not intended to limit the technical scope of the present invention, the mechanism by which such effects are obtained in the present invention is presumed to be as follows. By introducing a structural unit having a carboxyl group, such as that represented by the above formula (1), into the polymer chain terminal of a polycarbonate resin, it becomes easier to effectively coat the surface of inorganic fine particles, and high transparency can be maintained even under high-temperature conditions. Furthermore, since it is easier to coat the surface of inorganic fine particles, active hydroxyl groups on the surface of the inorganic fine particles are effectively shielded, which can suppress hydrolysis of the polymer under high-temperature conditions. As a result, it is possible to provide an organic-inorganic hybrid composition that achieves high transparency while suppressing hydrolysis and can be molded under high-temperature conditions.

[0017] The present invention will be described in detail below. <Polycarbonate resin> The polycarbonate resin used in the present invention is a polycarbonate resin having a structural unit represented by the following formula (1) at the polymer chain terminal.

[0018] [ka]

[0019] In formula (1), R 1 and R 2 may be independent or the same, and represent at least one group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cycloalkyl group, a cycloalkoxy group, an alkenyl group, an aryl group, an aryloxy group, an aralkyl group, an aralkyloxy group, a nitro group, an aldehyde group, and a cyano group; a and b each represent an integer of 1 to 2; X represents a single bond or a group represented by the following formula (2): [ka] where R is a divalent group represented by 5 represents at least one group selected from the group consisting of an alkylene group, an aralkylene group, an arylene group, and a cycloalkylene group; R 3 and R 4 each independently represents at least one group selected from the group consisting of an alkylene group, an aralkylene group, an arylene group, and a cycloalkylene group; R 4 The hydrogen atoms in may be substituted with carboxyl groups.

[0020] In the above formula (1), preferably, R 1 and R 2 R are each independently at least one group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a cycloalkyl group having 6 to 20 carbon atoms, a cycloalkoxy group having 6 to 20 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an aryl group having 6 to 14 carbon atoms, an aryloxy group having 6 to 14 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aralkyloxy group having 7 to 20 carbon atoms, a nitro group, an aldehyde group, a cyano group, and a carboxyl group. 1 and R 2 When there are a plurality of each of the above, they may be the same or different.

[0021] Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom. Examples of the alkyl group having 1 to 18 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a dodecyl group, and a tetradecyl group. An alkyl group having 1 to 6 carbon atoms is preferred.

[0022] Examples of the alkoxy group having 1 to 18 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group, a hexoxy group, an octoxy group, etc. An alkoxy group having 1 to 6 carbon atoms is preferred. Examples of the cycloalkyl group having 6 to 20 carbon atoms include a cyclohexyl group, a cyclooctyl group, etc. A cycloalkyl group having 6 to 12 carbon atoms is preferred.

[0023] Preferred examples of the cycloalkoxy group having 6 to 20 carbon atoms include a cyclohexyloxy group, a cyclooctyloxy group, etc. A cycloalkoxy group having 6 to 12 carbon atoms is preferred. Examples of the alkenyl group having 2 to 10 carbon atoms include a methenyl group, an ethenyl group, a propenyl group, a butenyl group, a pentenyl group, etc. An alkenyl group having 2 to 6 carbon atoms is preferred.

[0024] Examples of the aryl group having 6 to 14 carbon atoms include a phenyl group, a naphthyl group, etc. Examples of the aryloxy group having 6 to 14 carbon atoms include a phenyloxy group, a naphthyloxy group, etc. Examples of the aralkyl group having 7 to 20 carbon atoms include a benzyl group, a phenylethyl group, etc. Examples of the aralkyloxy group having 7 to 20 carbon atoms include a benzyloxy group, a phenylethyloxy group, etc.

[0025] Preferably, a and b in formula (1) are each an integer of 1 to 2, and more preferably, a and b are each an integer of 1. Preferably, R in formula (2) 5is at least one group selected from the group consisting of a single bond, an alkylene group having 1 to 10 carbon atoms, an aralkylene group having 7 to 20 carbon atoms, an arylene group having 6 to 10 carbon atoms, and a cycloalkylene group.

[0026] Preferably, R in formula (2) 3 and R 4 Each of them may be independent or the same, and represents at least one group selected from the group consisting of an alkylene group, an alkylidene group, an aralkylene group, an arylene group, and a cycloalkylene group. 3 and R 4 may be independent or the same and are each an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, or an aralkylene group having 7 to 20 carbon atoms, and more preferably an alkylene group having 1 to 6 carbon atoms, an arylene group having 6 to 10 carbon atoms, or an aralkylene group having 7 to 12 carbon atoms.

[0027] The molar ratio of the polymer chain terminals having the structural unit represented by formula (1) is preferably 1.0 mol % to 10 mol % relative to 100 mol % of all carbonate repeating units in the polycarbonate resin, more preferably 1.5 mol % to 8.0 mol %, even more preferably 2.0 mol % to 7.0 mol %, and particularly preferably 3.0 mol % to 6.0 mol %. Within the above ranges, the effects of the present invention can be fully exhibited.

[0028] (Preferred embodiment (1)) In the present invention, a preferred embodiment (1) is one in which the formula (1) contains a structural unit represented by the following formula (3):

[0029] [ka]

[0030] In equation (3), R 6represents at least one group selected from the group consisting of a single bond, an alkylene group, an aralkylene group, an arylene group, and a cycloalkylene group. 6 is preferably at least one group selected from the group consisting of a single bond, an alkylene group having 1 to 10 carbon atoms, an aralkylene group having 7 to 20 carbon atoms, an arylene group having 6 to 10 carbon atoms, and a cycloalkylene group.

[0031] Polycarbonate resins containing the structure represented by formula (3) at their polymer chain ends can be produced by conventional reaction methods for producing polycarbonate resins, such as using a phenolic compound having a carboxyl group as a terminal terminator, or by performing a polymerization reaction using a phenolic compound having a carboxylic acid ester group as a terminal terminator, followed by an acid modification reaction to convert the carboxylic acid ester group to a carboxyl group, or by both. Polymerization methods include interfacial polycondensation, melt transesterification, and solid-phase transesterification of carbonate prepolymers. Among these, interfacial polycondensation, in which a phenolic compound having a carboxyl group, a phenolic compound having a carboxylic acid ester group, or both, act as terminal terminators, is preferred from the perspective of quantitatively introducing the structure represented by formula (3) into the polymer chain ends.

[0032] Examples of phenol compounds having a carboxyl group that can be used as end terminators include 4-hydroxybenzoic acid, 3-hydroxybenzoic acid, and 2-hydroxybenzoic acid. From the viewpoint of efficiency of introduction into the polymerization terminal, 4-hydroxybenzoic acid and 3-hydroxybenzoic acid are preferred, and 4-hydroxybenzoic acid is more preferred. These may be used alone or in combination of two or more.

[0033] Examples of phenolic compounds having a carboxylic acid ester group that can be used as end terminators include tertiary butyl 4-hydroxybenzoate, isopropyl 4-hydroxybenzoate, and methyl 4-hydroxybenzoate. From the viewpoint of the efficiency of the deprotection reaction described below, tertiary butyl 4-hydroxybenzoate and isopropyl 4-hydroxybenzoate are preferred, and tertiary butyl 4-hydroxybenzoate is more preferred. These compounds may be used alone or in combination of two or more. By converting the carboxyl group into a carboxylic acid ester structure, hydrophobicity is improved and it becomes easier to quantitatively introduce the carboxyl group into the polymer chain terminal.

[0034] Phenol compounds not having a carboxyl group or a carboxylic acid ester group may be used in combination as a terminal terminator. Examples of phenol compounds not having a carboxyl group or a carboxylic acid ester group include phenol, m-methylphenol, p-methylphenol, m-propylphenol, p-propylphenol, 1-phenylphenol, 2-phenylphenol, p-tert-butylphenol, p-cumylphenol, isooctylphenol, and p-long-chain alkylphenol. By using these phenol compounds not having a carboxyl group in combination as a terminal terminator, the amount of carboxyl groups at the polymer chain ends can be quantitatively adjusted, and the thermal stability of the organic-inorganic hybrid composition, the dispersibility of inorganic fine particles, and the fluidity during melting can be controlled.

[0035] In the method using a phenolic compound having a carboxylic acid ester group, a polycarbonate resin is produced by a polymerization reaction, and then the carboxylic acid ester group is converted to a carboxyl group by an acid modification reaction, thereby converting the polymer chain end to a structure represented by formula (3). Examples of known acid modification reactions include, but are not limited to, a method in which an acidic compound is reacted with the resin, a heat treatment method, and the like. From the viewpoint of reaction efficiency, the method using an acidic compound is preferred. Examples of acidic compounds include, but are not limited to, strong acidic compounds such as trifluoroacetic acid and hydrochloric acid. From the viewpoint of reaction efficiency, trifluoroacetic acid is particularly preferred.

[0036] The production process of the acid modification reaction using an acidic compound may be, for example, a process of dissolving a solidified polymer in a solvent and reacting with an acidic compound, or in the case of a polymerization method using a solvent such as interfacial polycondensation, a process of reacting an acidic compound with a polymer solution after the polymerization reaction has been completed may be used.

[0037] (Preferred embodiment (2)) In the present invention, a preferred embodiment (2) is one in which the formula (1) contains a structural unit represented by the following formula (4):

[0038] [ka]

[0039] In equation (4), R 7 represents at least one group selected from the group consisting of an alkylene group, an aralkylene group, an arylene group, and a cycloalkylene group. 7 is preferably an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, or an aralkylene group having 7 to 20 carbon atoms, and more preferably an alkylene group having 1 to 6 carbon atoms, an arylene group having 6 to 10 carbon atoms, or an aralkylene group having 7 to 12 carbon atoms.

[0040] The polycarbonate resin used in the present invention and having the structure represented by formula (4) can be produced, for example, by a process (step (I)) of producing a polycarbonate resin having a carbon-carbon double bond and a process (step (II)) of reacting the polycarbonate resin with a thiol compound having a carboxyl group.

[0041] (Process I) Polycarbonate resins having carbon-carbon double bonds at the polymer chain terminals are produced by using at least one phenolic compound having a carbon-carbon double bond by a reaction method known per se for producing ordinary polycarbonate resins. Examples of reaction methods include interfacial polycondensation, melt transesterification, and solid-phase transesterification of carbonate prepolymers. Among these, the interfacial polycondensation method in which a phenolic compound having a carbon-carbon double bond acts as a terminal terminator is preferred from the viewpoint of quantitatively introducing the structure represented by formula (4) into the polymer chain terminals.

[0042] Examples of phenol compounds having a carbon-carbon double bond that can be used as end terminators include parahydroxyallylphenol, metahydroxyallylphenol, and orthohydroxyallylphenol. From the viewpoint of efficiency of introduction into the polymerization terminal, orthohydroxyallylphenol is particularly preferred. These compounds may be used alone or in combination of two or more.

[0043] Phenol compounds having no carbon-carbon double bonds may be used in combination as end terminators. Examples of phenol compounds having no carbon-carbon double bonds include phenol, m-methylphenol, p-methylphenol, m-propylphenol, p-propylphenol, 1-phenylphenol, 2-phenylphenol, p-tert-butylphenol, p-cumylphenol, isooctylphenol, and p-long-chain alkylphenol. By using these phenol compounds having no carbon-carbon double bonds in combination as end terminators, the amount of carboxyl groups at the polymer chain ends can be quantitatively adjusted, and the thermal stability of the organic-inorganic hybrid composition, the dispersibility of inorganic fine particles, and the fluidity during melting can be controlled.

[0044] (Process II) A polycarbonate resin having the structure represented by formula (4) can be produced by reacting the polycarbonate resin having a carbon-carbon double bond produced in step (I) with a thiol compound having a carboxyl group (enethiol reaction). The enethiol reaction is a reaction in which a carbon-carbon double bond and a thiol group are added in a one-to-one ratio. That is, when a thiol is irradiated with light or a radical generator is added, a thiyl radical is easily generated and added to the carbon-carbon double bond. The resulting carbon radical abstracts a hydrogen atom from the thiol group, producing a one-to-one adduct. The thiol group from which the hydrogen has been abstracted becomes a thiyl radical, leading to a chain reaction. In this way, the enethiol reaction can be used to quantitatively produce a polycarbonate resin having a carboxyl group in high yield.

[0045] Examples of thiol compounds having a carboxyl group include 3-mercaptopropanoic acid, 3-mercapto-2-methylpropanoic acid, mercaptosuccinic acid, 2-mercaptobenzoic acid, and 1-(mercaptomethyl)cyclopropaneacetic acid.

[0046] In the enethiol reaction, it is preferable to use a radical generator as a reaction catalyst. However, a radical reaction caused by irradiation with light (ultraviolet rays) may also be performed. Examples of radical generators include azo compounds and organic peroxides, and either those that generate radicals by heat or by irradiation with light can be suitably used. Examples of azo compounds include azobisisobutyronitrile (AIBN) and 1,1'-azobis(cyclohexanecarbonitrile) (ABCN). Examples of organic peroxides include di-tert-butyl peroxide and benzoyl peroxide.

[0047] More specifically, the enethiol reaction can be carried out by dissolving a polycarbonate resin having a carbon-carbon double bond, a thiol compound having a carboxyl group, and a radical generator in an organic solvent and maintaining the solution under conditions in which radicals are generated. Examples of organic solvents include alcohols (alkyl alcohols such as ethanol, propanol, and isopropanol, glycols such as ethylene glycol and propylene glycol), hydrocarbons (aliphatic hydrocarbons such as hexane, alicyclic hydrocarbons such as cyclohexane, aromatic hydrocarbons such as toluene and xylene), halogenated hydrocarbons (methylene chloride, chloroform, etc.), ethers (chain ethers such as dimethyl ether and diethyl ether, cyclic ethers such as dioxane and tetrahydrofuran), esters (methyl acetate, ethyl acetate, butyl acetate, ethyl lactate, ethyl butyrate, etc.), ketones (acetone, ethyl methyl ketone, methyl isobutyl ketone, cyclohexanone, N-methyl-2-pyrrolidone, etc.), Examples of organic solvents include cellosolves (methyl cellosolve, ethyl cellosolve, butyl cellosolve, etc.), carbitols (methyl carbitol, ethyl carbitol, butyl carbitol, etc.), propylene glycol monoalkyl ethers (propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-butyl ether, etc.), glycol ether esters (ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, etc.), amides (N,N-dimethylformamide, N,N-dimethylacetamide, etc.), sulfoxides (dimethyl sulfoxide, etc.), nitriles (acetonitrile, benzonitrile, etc.), and N-methylpyrrolidone. These organic solvents may be used alone or in combination. The reaction temperature is not particularly limited, but is preferably 50 to 120°C.

[0048] (Other units) Examples of units other than the polymer chain terminals, i.e., main chain units, include various diol compounds. Such diol compounds may be aromatic diol compounds, aliphatic diol compounds, or alicyclic diol compounds, including the diol compounds described in International Publication Nos. 2004 / 111106 and 2011 / 021720, and oxyalkylene glycols such as diethylene glycol, triethylene glycol, tetraethylene glycol, and polyethylene glycol. These may be used alone or in combination. Representative examples of diol components are shown below, but the other components of the present invention are not limited thereto.

[0049] Specific examples of aromatic diol compounds include 4,4'-biphenol, 3,3',5,5'-tetrafluoro-4,4'-biphenol, α,α'-bis(4-hydroxyphenyl)-o-diisopropylbenzene, α,α'-bis(4-hydroxyphenyl)-m-diisopropylbenzene (commonly referred to as "BPM"), α,α'-bis(4-hydroxyphenyl)-p-diisopropylbenzene, α,α'-bis(4-hydroxyphenyl)-m-bis(1,1,1,3,3,3-hexafluoroisopropyl)benzene, 1,1 ...1,1-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,1-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,1-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,1-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,1-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,1-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,1-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,1-bis(4-hydroxyphenyl)-p-diisopropylbenzene, 1,1- 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 1,1-bis(4-hydroxyphenyl)-4-isopropylcyclohexane, 1,1-bis(3-cyclohexyl-4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)cyclopentane, 1,1-bis(3-fluoro-4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)perfluorocyclohexane, 4,4'-dihydroxydiphenyl ether, 4,4'- Dihydroxy-3,3'-dimethyldiphenyl ether, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxydiphenyl sulfide (hereinafter sometimes abbreviated as "TDP"), 3,3'-dimethyl-4,4'-dihydroxydiphenyl sulfide (hereinafter sometimes abbreviated as "HMPS"), 3,3'-dimethyl-4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxy-3,3'-diphenyl sulfide, 4,4'-dihydro 4,4'-dihydroxy-3,3'-diphenyl sulfoxide, 4,4'-dihydroxy-3,3'-diphenyl sulfone, 1,1-bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)propane (commonly referred to as "BPA"), 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2,2-bis(4-hydroxy-3-methylphenyl)propane (commonly referred to as "BPC"), 9,9-bis(4-hydroxyphenyl)fluorene (hereinafter sometimes abbreviated as "BPF"), 9,9-bis(4-hydroxy-3-methylphenyl)fluorene (hereinafter sometimes abbreviated as "BCF"), 9,9-bis(4-hydroxy-3-phenylphenyl)fluorene (hereinafter sometimes abbreviated as "BPPF"), 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)pentane, 2,2-bis(4-hydroxy-3-phenylphenyl)propane, 2,2-bis(3-isopropyl-4-hydroxyphenyl)propane, 2,2-bis(3-t-butyl-4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)pentane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)pentane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)but ... Bis(4-hydroxyphenyl)butane, 4,4-bis(4-hydroxyphenyl)heptane, 2,2-bis(4-hydroxyphenyl)octane, 1,1-bis(4-hydroxyphenyl)decane, 1,1-bis(3-methyl-4-hydroxyphenyl)decane, 1,1-bis(2,3-dimethyl-4-hydroxyphenyl)decane, 2,2-bis(3-bromo-4-hydroxyphenyl)propane, bis(4-hydroxyphenyl)diphenylmethane, 1,1-bis(4-hydroxyphenyl)-4-isopropylcyclohexane, 2,2-bis(4-hydroxyphenyl)decane, 1,1 ... Bis(4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane (commonly referred to as "BPAF"), 6,6'-dihydroxy-3,3,3',3'-tetramethyl-1,1'-spirobiindane, 7,7'-dimethyl-6,6'-dihydroxy-3,3,3',3'-tetramethyl-1,1'-spirobiindane, 7,7'-diphenyl-6,6'-dihydroxy-3,3,3',3'-tetramethyl-1,1'-spirobiindane, 2,2-bis(4-hydroxy-3-methylphenyl)-1,1,1,3,3,3-hexafluoropropane Fluoropropane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-bis(3-fluoro-4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane, and 2,2-bis(3,5-difluoro-4-hydroxyphenyl)-1,1,1,3,3,3-hexafluoropropane, 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane, 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane, and 2,2-bis(3-cyclohexyl-4-hydroxyphenyl)propane. Among the above, BPM, TDP, HMPS, BPA, BPC, BPF, BCF, and BPPF are preferred.

[0050] Aliphatic diol compounds include 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 2-n-butyl-2-ethyl-1, Examples include 3-propanediol, 2,2-diethyl-1,3-propanediol, 2,4-diethyl-1,5-pentanediol, 1,2-hexane glycol, 1,2-octyl glycol, 2-ethyl-1,3-hexanediol, 2,3-diisobutyl-1,3-propanediol, 2,2-diisoamyl-1,3-propanediol, and 2-methyl-2-propyl-1,3-propanediol.

[0051] Examples of the alicyclic diol compound include cyclohexanedimethanol, tricyclodecane dimethanol, adamantanediol, pentacyclopentadecanedimethanol, 2,2,4,4-tetramethyl-1,3-cyclobutanediol, and isosorbide (1,4;3,6-dianhydro-D-sorbitol).

[0052] (Method for producing polycarbonate resin polymer) In reactions using, for example, phosgene as a carbonate precursor, the reaction is usually carried out in the presence of an acid binder and a solvent. Examples of acid binders include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and amine compounds such as pyridine. Examples of solvents include halogenated hydrocarbons such as methylene chloride and chlorobenzene. To promote the reaction, a catalyst such as a tertiary amine or a quaternary ammonium salt can also be used. The reaction temperature is usually 0 to 40°C, and the reaction time is several minutes to 5 hours.

[0053] Transesterification using, for example, a carbonate diester as a carbonate precursor is carried out by stirring a predetermined proportion of aromatic dihydroxy component with the carbonate diester under heating in an inert gas atmosphere, and distilling off the resulting alcohol or phenol. The reaction temperature varies depending on the boiling point of the resulting alcohol or phenol, but is typically in the range of 120 to 300°C. The reaction is completed by reducing the pressure from the beginning of the reaction to distill off the resulting alcohol or phenol. A catalyst typically used in transesterification can also be used to promote the reaction. Examples of carbonate diesters used in the transesterification reaction include diphenyl carbonate, dinaphthyl carbonate, bis(diphenyl)carbonate, dimethyl carbonate, diethyl carbonate, and dibutyl carbonate. Of these, diphenyl carbonate is particularly preferred.

[0054] The polycarbonate resin of the present invention can be copolymerized with a fatty acid, if necessary, such as 1,10-dodecanedioic acid, adipic acid, hexanedioic acid, isophthalic acid, 1,3-benzenedicarboxylic acid, terephthalic acid, 1,4-benzenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 3-hydroxybenzoic acid, and 4-hydroxybenzoic acid.

[0055] The polycarbonate resin of the present invention includes a polyester carbonate copolymerized with an aromatic or aliphatic (including alicyclic) bifunctional carboxylic acid. The aliphatic bifunctional carboxylic acid is preferably an α,ω-dicarboxylic acid. Preferred examples of the aliphatic bifunctional carboxylic acid include linear saturated aliphatic dicarboxylic acids such as sebacic acid (decanedioic acid), dodecanedioic acid, tetradecanedioic acid, octadecanedioic acid, and icosane dicarboxylic acid, as well as alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. These carboxylic acids may be copolymerized to the extent that the objective is not impaired. The polycarbonate resin of the present invention may also be copolymerized with a structural unit containing a polyorganosiloxane unit, if necessary.

[0056] The polycarbonate resin of the present invention can also be made into a branched polycarbonate by copolymerizing a structural unit containing a trifunctional or higher polyfunctional aromatic compound, if necessary. Suitable examples of trifunctional or higher polyfunctional aromatic compounds used in branched polycarbonates include 4,6-dimethyl-2,4,6-tris(4-hydroxydiphenyl)heptene-2,2,4,6-trimethyl-2,4,6-tris(4-hydroxyphenyl)heptane, 1,3,5-tris(4-hydroxyphenyl)benzene, 1,1,1-tris(4-hydroxyphenyl)ethane, 1,1,1-tris(3,5-dimethyl-4-hydroxyphenyl)ethane, 2,6-bis(2-hydroxy-5-methylbenzyl)-4-methylphenol, and trisphenols such as 4-{4-[1,1-bis(4-hydroxyphenyl)ethyl]benzene}-α,α-dimethylbenzylphenol. Of these, 1,1,1-tris(4-hydroxyphenyl)ethane is preferred. The structural units derived from such polyfunctional aromatic compounds preferably account for 0.03 to 1.5 mol %, more preferably 0.1 to 1.2 mol %, and particularly preferably 0.2 to 1.0 mol %, of a total of 100 mol % including structural units derived from other divalent components.

[0057] The branched structural units may be derived not only from polyfunctional aromatic compounds but also from side reactions occurring during polymerization by melt transesterification without using polyfunctional aromatic compounds. 1 It can be calculated by H-NMR measurement.

[0058] (viscosity average molecular weight) The viscosity average molecular weight of the polycarbonate resin of the present invention is preferably 5,000 to 40,000, more preferably 8,000 to 30,000, still more preferably 10,000 to 25,000, and particularly preferably 12,000 to 23,000. A range like this is preferred because it provides an excellent balance between moldability and mechanical strength.

[0059] The viscosity average molecular weight of the polycarbonate resin of the present invention can be determined by first calculating the specific viscosity (η SP ) was determined using an Ostwald viscometer from a solution of 0.7 g of resin dissolved in 100 ml of methylene chloride at 20°C. Specific viscosity (η SP )=(t-t0) / t0 [t0 is the number of seconds that methylene chloride falls, and t is the number of seconds that the sample solution falls] The calculated specific viscosity (η SP ) and the viscosity average molecular weight Mv was calculated using the following formula: η SP / c=[η]+0.45×[η] 2 c (where [η] is the intrinsic viscosity) [η]=1.23×10 -4 Mv 0.83 c=0.7

[0060] (glass transition temperature: Tg) The glass transition temperature (Tg) of the polycarbonate resin is preferably 90 to 200°C, more preferably 100 to 190°C, and even more preferably 110 to 180°C. A Tg within the above range is preferred because it provides good heat resistance stability and moldability when used as an optically molded article. The glass transition temperature (Tg) is measured using a 2910 DSC manufactured by TA Instruments Japan, Inc., at a heating rate of 20°C / min.

[0061] (carboxyl group amount) The amount of carboxyl groups in the polycarbonate resin of the present invention is preferably 1 to 200 eq / ton, more preferably 10 to 170 eq / ton, even more preferably 30 to 150 eq / ton, and particularly preferably 50 to 120 eq / ton. If the amount of carboxyl groups is equal to or greater than the lower limit, the dispersion stability of inorganic fine particles under high-temperature conditions is sufficient, and a transparent organic-inorganic hybrid composition can be obtained. If the amount is equal to or less than the upper limit, a decrease in the molecular weight of the polycarbonate resin can be suppressed, which can have a favorable effect on physical properties.

[0062] The amount of carboxyl groups in the present invention can be measured, for example, as follows: First, polycarbonate resin is dissolved in benzyl alcohol under a nitrogen atmosphere, and titrated with a benzyl alcohol solution of sodium hydroxide using phenol red as an indicator, and the amount of carboxyl groups is calculated from the amount of the solution added.

[0063] <Inorganic fine particles> The inorganic fine particles used in the present invention are preferably modified with a surface modifier. The inorganic fine particles preferably have an average particle size in the nanoscale range of 20 nm or less and are preferably modified with a surface modifier having an acidic functional group.

[0064] Examples of types of inorganic fine particles include ZrO2 (zirconium oxide), TiO2 (titanium oxide), SnO2 (tin oxide), SiO2 (silicon oxide), Al2O3 (aluminum oxide), etc. Among these, in the present invention, ZrO2 and TiO2 are preferred from the viewpoint of use as optical members and optical components, with ZrO2 being particularly preferred.

[0065] The surface modifier for inorganic fine particles in the present invention is not particularly limited as long as it can ensure the dispersibility of the inorganic fine particles in the polycarbonate resin or the like to be composited, but it is preferable that the surface modifier has an acidic functional group such as a sulfonic acid group, a phosphonic acid group, a phosphinic acid group, or a carboxylic acid group, as this provides excellent dispersibility and refractive index improvement effects. Representative examples of surface modifiers are shown below, but the surface modifier of the present invention is not limited thereto. They may be used alone, or multiple types may be used in combination. In particular, when dispersing inorganic fine particles after surface modification treatment in a resin, it is desirable to appropriately select and use a surface modifier that easily improves affinity with the resin, depending on the type of resin.

[0066] Examples of sulfonic acids include alkylsulfonic acids such as butanesulfonic acid, hexanesulfonic acid, and dodecanesulfonic acid, and arylsulfonic acids such as benzenesulfonic acid, methylbenzenesulfonic acid, and dodecylbenzenesulfonic acid. Among these, arylsulfonic acids are preferred in view of their dispersibility in resins and their effect of improving the refractive index.

[0067] Examples of phosphonic acids include alkylphosphonic acids such as propanephosphonic acid, and arylphosphonic acids such as benzenephosphonic acid. Among these, arylphosphonic acids are preferred in view of their dispersibility in resins and their effect of improving the refractive index.

[0068] Examples of phosphinic acids include alkylphosphinic acids such as dimethylphosphinic acid, diethylphosphinic acid, and di(2-ethylhexyl)phosphinic acid, and arylphosphinic acids such as phenylphosphinic acid and diphenylphosphinic acid. Furthermore, by using thiophosphinic acid or dithiophosphinic acid, in which the oxygen atoms constituting the phosphinic acid group are replaced with sulfur atoms, inorganic particles with a higher refractive index than those obtained by using phosphinic acid can be obtained. Among these, in view of dispersibility in resins and the effect of improving the refractive index, arylphosphinic acids are preferred, phenylphosphinic acid and diphenylphosphinic acid are more preferred, and diphenylphosphinic acid is particularly preferred.

[0069] Examples of carboxylic acids include alkyl carboxylic acids such as butanoic acid, isobutanoic acid, methacrylic acid, hexanoic acid, octanoic acid, oleic acid, linoleic acid, and lauric acid, and aryl carboxylic acids such as benzoic acid, hydroxybenzoic acid, and phenoxybenzoic acid. Furthermore, by using thiocarboxylic acids or dithiocarboxylic acids in which the oxygen atom constituting the carboxyl group of a carboxylic acid is replaced with a sulfur atom, inorganic fine particles with a higher refractive index than when a carboxylic acid is used can be obtained. Among these, in view of dispersibility in resins and the effect of improving the refractive index, aryl carboxylic acids are preferred, and phenoxybenzoic acids having a phenoxy group at the ortho, meta, or para position are more preferred, with paraphenoxybenzoic acid being particularly preferred.

[0070] The surface modification of inorganic fine particles in the present invention is carried out, for example, by the following process. That is, a surface modifier having an acidic functional group is added to a mixture of a transparent aqueous dispersion in which hydrophilic inorganic fine particles having an average particle size of about 20 nm or less are dispersed and methanol, and then the water and methanol are removed by azeotropy and the solvent is replaced with toluene or methylene chloride to prepare a toluene dispersion or methylene chloride dispersion in which the surface-modified inorganic fine particles are dispersed. The solvent is then distilled off to obtain a white powder of the surface-modified inorganic fine particles.

[0071] In inorganic fine particles modified with a surface modifier, the content of the surface modifier relative to the inorganic fine particles is preferably 1 to 30% by mass, more preferably 3 to 28% by mass, and particularly preferably 5 to 25% by mass, in consideration of dispersibility in resin and the effect of improving the refractive index. From the viewpoint of dispersibility in a resin composite, the higher the content of the surface modifier, the better, while from the viewpoint of the effect of improving the refractive index, the lower the content of the surface modifier, the better. It is desirable to adjust the content of the surface modifier appropriately depending on the dispersibility and the desired refractive index.

[0072] <Components other than polycarbonate resin and inorganic fine particles> The organic-inorganic hybrid composition of the present invention may contain, in addition to the polycarbonate resin and inorganic fine particles, functional agents known per se, such as a release agent, a heat stabilizer, an ultraviolet absorber, a flow modifier, and an antistatic agent, within the range that does not impair the effects of the present invention.

[0073] The method for blending a resin other than the polycarbonate resin and an additive into the organic-inorganic composite composition of the present invention is not particularly limited, and any known method can be used. The most commonly used method is to premix the polycarbonate resin, inorganic fine particles, and additives, then feed the mixture into an extruder to melt-knead, cool the extruded thread, and cut it with a pelletizer to produce a pellet-shaped molding material.

[0074] <Method of producing organic-inorganic composite composition> The method for producing the organic-inorganic hybrid composition of the present invention includes obtaining a polycarbonate resin having a structure represented by formula (1) at the polymer chain terminal, and dispersing inorganic fine particles whose surfaces have been modified with a surface modifier in the polycarbonate resin.

[0075] The step of dispersing inorganic fine particles in polycarbonate resin is not particularly limited, but specific examples include a method of mixing a polycarbonate resin solution with an inorganic fine particle dispersion, and a method of melt-mixing polycarbonate resin powder with inorganic fine particle powder, and any of these methods may be used to prepare the dispersion.

[0076] For example, in the method of mixing a polycarbonate resin solution and an inorganic particle dispersion, the polycarbonate resin solution and the inorganic particle dispersion may be mixed at once, or the polycarbonate resin solution may be gradually added dropwise to the inorganic particle dispersion and mixed. In addition, a plasticizer may be present, and such a plasticizer may be added to the resin solution or the inorganic particle dispersion in advance, or may be added when the resin solution and the inorganic particle dispersion are mixed.

[0077] The content of inorganic fine particles in the organic-inorganic hybrid composition of the present invention is preferably 1 to 50 mass %, more preferably 3 to 40 mass %, and most preferably 5 to 30 mass %. If the surface-modified inorganic fine particles are less than the lower limit, it is difficult to obtain the effect of containing the inorganic fine particles, and if the content exceeds the upper limit, the strength of the organic-inorganic hybrid decreases.

[0078] An organic-inorganic composite composition containing a polycarbonate resin having the structure represented by formula (1) at the polymer chain terminal and inorganic fine particles surface-modified with a surface modifier can also be added to another resin as a master resin and mixed for use. By using this method, it is possible to adjust the refractive index and Abbe number within any range and obtain an organic-inorganic composite composition suitable as an optical resin.

[0079] (Molding method) The organic-inorganic composite composition of the present invention can be molded by common molding methods for polycarbonate resins, such as injection molding, extrusion molding, compression molding, and solution casting. The organic-inorganic composite composition of the present invention has excellent transparency and a high refractive index, and can therefore be used to form a variety of molded articles. In particular, the composition can be advantageously used as molded articles suitable for structural materials for optical components such as optical lenses, optical disks, liquid crystal panels, optical cards, sheets, films, optical fibers, connectors, vapor-deposited plastic reflectors, and displays; electrical and electronic components such as exteriors and front panels for personal computers and mobile phones; automotive applications such as automobile headlamps and windows; or functional material applications, and is particularly suitable for optical lenses and optical films.

[0080] (Average particle size) In the organic-inorganic hybrid composition of the present invention, the inorganic fine particles have an average particle size of preferably 1 to 100 nm, more preferably 1 to 50 nm, and even more preferably 1 to 20 nm. If the average particle size exceeds the upper limit of this range, the transparency of the organic-inorganic hybrid composition may be insufficient.

[0081] (transmittance) The organic-inorganic hybrid composition of the present invention preferably has high transmittance. A molded article having a thickness of 1 mm preferably has a D-ray transmittance of 70% or more, and more preferably has a D-ray transmittance of 80% or more. By satisfying these properties, the composition can be suitably used for optical lenses and optical films.

[0082] (refractive index) The refractive index (hereinafter sometimes abbreviated as nD) of the organic-inorganic hybrid composition of the present invention at a wavelength of 589 nm measured at 25° C. is preferably 1.500 to 2.000. When the refractive index is equal to or greater than the lower limit, the spherical aberration of the lens can be reduced, and further the focal length of the lens can be shortened. [Example]

[0083] The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. In the examples, "parts" means "parts by mass." The polycarbonate resin, inorganic fine particles, and evaluation methods used in the examples are as follows.

[0084] <Evaluation method> (composition ratio) Each repeating unit was measured by proton NMR using JNM-AL400 manufactured by JEOL Ltd., and the polymer composition ratio (molar ratio) was calculated.

[0085] (viscosity average molecular weight) The specific viscosity (η SP ) was measured using an Ostwald viscometer from a solution of 0.7 g of sample dissolved in 100 ml of methylene chloride at 20°C. Specific viscosity (ηSP )=(t-t0) / t0 [t0 is the number of seconds that methylene chloride falls, and t is the number of seconds that the sample solution falls] The calculated specific viscosity (η SP ) and the viscosity average molecular weight Mv was calculated using the following formula: η SP / c=[η]+0.45×[η] 2 c (where [η] is the intrinsic viscosity) [η]=1.23×10 -4 Mv 0.83 c=0.7

[0086] (glass transition temperature (Tg)) Using 8 mg of sample, measurements were performed using a thermal analysis system DSC-2910 manufactured by TA Instruments Co., Ltd. in accordance with JIS K7121 under conditions of a nitrogen atmosphere (nitrogen flow rate: 40 ml / min) and a heating rate of 20°C / min.

[0087] (carboxyl group amount) The sample was dissolved in benzyl alcohol under a nitrogen atmosphere, and the content was calculated by titrating with a benzyl alcohol solution of sodium hydroxide using phenol red as an indicator.

[0088] (Moldability) The pellets were melted and mixed in an extruder and molded in an injection molding machine (Japan Steel Works J-75E3) under conditions of a cylinder temperature of 300°C, a mold temperature of 80°C, a dwell time of 20 seconds, and a cooling time of 20 seconds to form three-layer resin plates measuring 50 mm wide, 90 mm long, and 3 mm (20 mm long), 2 mm (45 mm long), and 1 mm (25 mm long) thick from the gate side. Various evaluations were performed. If a three-layer resin plate was obtained under the above conditions, it was rated as "◎." If a resin plate was obtained but had poor appearance such as the generation of bubbles, it was rated as "〇." If a resin plate could not be obtained due to insufficient resin strength due to hydrolysis or other reasons, it was rated as "×."

[0089] (Average particle size) The pellets melted and mixed in the extruder were press-molded using a hot press molding machine (Shinto Metal Industries Co., Ltd., compression molding machine: SFV-10, vacuum pump unit: GXD-360) to obtain a molded plate approximately 1 mm thick. The press molding conditions were a mold temperature of 220°C, a primary pressure of 1 MPa (30 seconds), and a secondary pressure of 1.5 MPa (5 minutes). The molded plate was cut to prepare ultrathin sections, which were attached to a grid (JEOL Ltd., EM FINE GRID No. 2632 F-200-CU 100PC / CA), and observed using a JEOL Ltd., TEM JEM-2100 transmission electron microscope at an accelerating voltage of 200 kV.

[0090] Particle analysis was performed using micrographs taken at a magnification of 100,000x with the image analysis software WinROOF Ver. 6.6 (Mitani Corporation) to obtain the average size and particle size distribution (frequency distribution) of inorganic particles in the sample slice. The maximum major axis (the length between any two points on the outer contour of the particle chosen so that the distance between them is the maximum) was used as the size of each particle. Similar analysis was performed on three sample slices, and the average value was used as the value for each sample.

[0091] (transparency) The three-stage resin plate obtained by injection molding was evaluated as ◯ when the spectral transmittance at 589 nm in a thickness of 1.0 mm was 80% or more, and x when it was less than 80%.

[0092] (refractive index) The refractive index (nD) (wavelength: 589 nm) of the three-stage resin plate obtained by injection molding at 25° C. was measured using an ATAGO DR-M2 Abbe refractometer.

[0093] <Production of polycarbonate resin> (Production Example 1) (Polymerization reaction) A reactor equipped with a thermometer, stirrer, and reflux condenser was charged with 8,523 parts of ion-exchanged water and 3,787 parts of 25% aqueous sodium hydroxide. 901 parts of 2,2-bis(4-hydroxyphenyl)propane (hereinafter sometimes referred to as BPA) and 1,010 parts of 2,2-bis(4-hydroxy-3-methylphenyl)propane (hereinafter sometimes referred to as BPC) were dissolved as dihydric phenols, and 5.73 parts of hydrosulfite were dissolved. 6,708 parts of methylene chloride was then added, and 1,000 parts of phosgene (hereinafter sometimes abbreviated as "FH") was bubbled in over 70 minutes at 16-24°C with stirring. 631 parts of 25% aqueous sodium hydroxide was then added, followed by a solution of 58.2 parts of tert-butyl 4-hydroxybenzoate (Fujifilm Wako Pure Chemical Industries, Ltd.) dissolved in 580 parts of methylene chloride as an end-capping agent. The mixture was stirred to form an emulsion, and then vigorously stirred again. With stirring, 2.0 parts of triethylamine was added when the reaction solution was at 28°C, and stirring was continued for 1 hour at a temperature of 26-31°C to terminate the reaction. After the reaction was completed, the organic phase was separated, diluted with methylene chloride, and repeatedly washed with water. When the washings became neutral, it was washed with hydrochloric acid-acidified water. After that, it was repeatedly washed with ion-exchanged water, and when the conductivity of the aqueous phase became almost the same as that of the ion-exchanged water, it was placed in a kneader filled with warm water, and the methylene chloride was evaporated while stirring to obtain a resin powder. After dehydration, it was dried for 12 hours at 100°C in a hot air circulation dryer.

[0094] (Acid denaturation reaction) 500 parts of this resin powder was placed in a reactor equipped with a thermometer, stirrer, and reflux condenser and dissolved in 650 parts of methylene chloride. 500 parts of trifluoroacetic acid (Fujifilm Wako Pure Chemical Industries, Ltd.) was added over 30 minutes while stirring, and the reaction was terminated by continuing stirring at a temperature of 20-30°C for 5 hours. After the reaction was completed, the mixture was diluted with methylene chloride and repeatedly washed with ion-exchanged water until the conductivity of the aqueous phase was almost the same as that of the ion-exchanged water. The mixture was then placed in a kneader filled with warm water, and the methylene chloride was evaporated while stirring to obtain resin powder. After dehydration, the mixture was dried in a hot air circulating dryer at 100°C for 12 hours. The resulting resin had a viscosity-average molecular weight of 19,800, a glass transition temperature of 130°C, and a carboxyl group content of 68 eq / ton.

[0095] (Production Example 2) This was produced in the same manner as in Production Example 1, except that the dihydric phenol was changed to 1,988 parts of BPA, and the end terminators were changed to 54.1 parts of tert-butyl 4-hydroxybenzoate and 7,401 parts of methylene chloride.

[0096] (Acid denaturation reaction) It was produced in the same manner as in Production Example 1. The viscosity average molecular weight of the obtained resin was 22,300, the glass transition temperature was 148°C, and the amount of carboxyl groups was 72 eq / ton.

[0097] (Production Example 3) (Polymerization reaction) This was produced in the same manner as in Production Example 1, except that the dihydric phenols were changed to 2,538 parts of 9,9-bis(4-hydroxy-3-phenylphenyl)fluorene (hereinafter sometimes referred to as BPPF) and 735 parts of 4,4'-dihydroxydiphenyl sulfide (hereinafter sometimes referred to as TDP), and the end-capping agents were changed to 83.3 parts of tert-butyl 4-hydroxybenzoate and 7,154 parts of methylene chloride.

[0098] (Acid denaturation reaction) It was produced in the same manner as in Production Example 1. The viscosity average molecular weight of the obtained resin was 15,000, the glass transition temperature was 179°C, and the amount of carboxyl groups was 112 eq / ton.

[0099] (Production Example 4) (Polymerization reaction) A resin powder was obtained in the same manner as in Production Example 1, except that the dihydric phenol was changed to 901 parts of BPA and 1010 parts of BPC, and the end terminator was changed to 40.2 parts of 2-allylphenol (manufactured by Tokyo Chemical Industry Co., Ltd.).

[0100] (Acid denaturation reaction) 500 parts of this resin powder and 5,000 parts of 1,2-dichloroethane were added to a reactor equipped with a thermometer, stirrer, and reflux condenser and dissolved. Then, 117 parts of azobisisobutyronitrile (AIBN) and 150 parts of 3-mercaptopropanoic acid were added and heated to 70°C under a nitrogen atmosphere for 4 hours. After the reaction was completed, the reaction solution was added to acetone to precipitate a polycarbonate resin, and the precipitate was collected by vacuum filtration. The precipitate was then dissolved in methylene chloride and added to acetone to precipitate a polycarbonate resin. The precipitate was then collected by vacuum filtration and dried to obtain a polycarbonate resin powder. The resulting resin had a viscosity average molecular weight of 20,300, a glass transition temperature of 136°C, and a carboxyl group content of 58 eq / ton.

[0101] (Production Example 5) (Polymerization reaction) A resin powder was obtained in the same manner as in Production Example 1, except that the dihydric phenols were changed to 1,712 parts of BPA and 122 parts of 2,2-bis(3-allyl-4-hydroxyphenyl)propane (hereinafter referred to as BPDAL), and the end terminator was changed to 47.3 parts of p-tert-butylphenol.

[0102] (Acid denaturation reaction) It was produced in the same manner as in Production Example 4. The viscosity average molecular weight of the obtained resin was 20,400, the glass transition temperature was 132°C, and the amount of carboxyl groups was 228 eq / ton.

[0103] (Production Example 6) The resin was produced in the same manner as in Production Example 1 (polymerization reaction), except that the end terminator was changed to 45.0 parts of p-tert-butylphenol, and no acid modification reaction was carried out. The viscosity average molecular weight of the resulting resin was 20,000, and the glass transition temperature was 131°C.

[0104] (Production Example 7) The resin was produced in the same manner as in Production Example 2 (polymerization reaction), except that the end terminator was changed to 41.8 parts of p-tert-butylphenol, and no acid modification reaction was carried out. The viscosity average molecular weight of the resulting resin was 22,000, and the glass transition temperature was 146°C.

[0105] (Production Example 8) The resin was produced in the same manner as in Production Example 3 (polymerization reaction), except that the end terminator was changed to 64.4 parts of p-tert-butylphenol, and no acid modification reaction was carried out. The viscosity average molecular weight of the resulting resin was 15,200, and the glass transition temperature was 180°C.

[0106] <Production of inorganic fine particles> (Production Example 9) 3.84 g of paraphenoxybenzoic acid (surface modifier) ​​was placed in a 2 L recovery flask equipped with a stirrer tip, and dissolved in 300 mL of methanol and 700 mL of chloroform. Next, 37.2 g of ZrO2 aqueous dispersion (Sakai Chemical Industry Co., Ltd.: SZR-W) was added dropwise over 15 minutes. The mixture was stirred at room temperature for 1 hour, and then the solvent was removed using a rotary evaporator until the volume was approximately 200 mL. The removal was performed by reducing the pressure to a level that did not cause bumping within the liquid phase. An additional 300 mL of methanol and 700 mL of chloroform were added to the mixture to again obtain a transparent dispersion with no interface, and the solvent was again removed until the volume was approximately 200 mL. This procedure was repeated three times to obtain a powdery solid.

[0107] 500 mL of methylene chloride was added to the solid, again forming a transparent dispersion with no interface, and the solvent was distilled off until the volume was approximately 100 mL. This process was repeated three times, replacing the water / methanol / chloroform mixed solvent with methylene chloride alone, yielding a methylene chloride dispersion of ZrO2 nanoparticles. This methylene chloride dispersion was then vacuum dried at room temperature for 24 hours to remove the methylene chloride, and then further dried at 120°C for 48 hours to obtain surface-modified ZrO2 powder.

[0108] (Production Example 10) A surface-modified ZrO2 powder was obtained in the same manner as in Production Example 9, except that 1.34 g of diphenylphosphinic acid was used as the surface modifier.

[0109] <Production of Organic-Inorganic Composite Composition> [Examples 1 to 6, Comparative Examples 1 to 4] The inorganic fine particles were dispersed in methylene chloride, and the methylene chloride solution of polycarbonate resin was added dropwise over 5 minutes, followed by stirring for 30 minutes. This methylene chloride dispersion was dried at 80°C for 4 hours to remove the methylene chloride, and then further dried at 120°C for 24 hours to obtain flakes of organic-inorganic composite. These flakes were melt-kneaded in a twin-screw extruder (Technovel KZW15-25MG) at a cylinder and die temperature of 300°C, and the extruded resin was cooled in a water bath and cut into pellets using a pelletizer. The extruded pellets were molded using an injection molding machine (J-75E3 manufactured by Japan Steel Works) under conditions of a cylinder temperature of 300°C, a mold temperature of 80°C, a dwell time of 20 seconds, and a cooling time of 20 seconds to form a three-tiered resin plate with a width of 50 mm, a length of 90 mm, and thicknesses from the gate side of 3 mm (20 mm length), 2 mm (45 mm length), and 1 mm (25 mm length). Various evaluations were performed, and the results are shown in Table 3. The type of resin, type of surface modifier, and amount of inorganic fine particles added are as shown in Table 3.

[0110] [Table 1]

[0111] [Table 2]

[0112] [Table 3]

[0113] As in Examples 1 to 6, when the polycarbonate resin of the present invention was used, an organic-inorganic hybrid composition excellent in moldability, transparency, and refractive index was provided. When a polycarbonate resin having carboxyl groups in the side chain but not at the polymer chain end was used as in Comparative Example 1, decomposition was significant and melt moldability was poor. When a polycarbonate resin having no carboxyl groups at the polymer chain end was used as in Comparative Examples 2 to 4, the inorganic fine particles could not be uniformly dispersed, the fine particles aggregated, and the transmittance was low.

[0114] 1 shows a TEM image of the organic-inorganic hybrid composition obtained in Example 1. The composition was highly transparent and the inorganic fine particles were uniformly dispersed. 2 shows a TEM image of the organic-inorganic hybrid composition obtained in Comparative Example 3. The composition had low transparency and inorganic fine particles were aggregated. [Industrial Applicability]

[0115] The organic-inorganic hybrid composition of the present invention is excellent in transparency, refractive index, and moldability. Furthermore, the refractive index and other properties can be adjusted as desired by adjusting the content of inorganic fine particles. Therefore, molded articles, films, and sheets obtained using the present invention can be used in a variety of fields.

Claims

1. The present invention comprises a polycarbonate resin containing a structural unit represented by the following formula (1) at a polymer chain terminal, and inorganic fine particles, wherein the inorganic fine particles are ZrO ２ (zirconium oxide), TiO ２ (Titanium oxide), SnO ２ (tin oxide), SiO ２ (silicon oxide), and Al ２ O ３ (aluminum oxide). 【Chemistry 1】 (In formula (1), R １ and R ２ may be independent or the same, and represent at least one group selected from the group consisting of a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cycloalkyl group, a cycloalkoxy group, an alkenyl group, an aryl group, an aryloxy group, an aralkyl group, an aralkyloxy group, a nitro group, an aldehyde group, and a cyano group; a and b each represent an integer of 1 to 2; X represents a single bond or a group represented by the following formula (2): 【Chemistry 2】 where R ５ represents at least one group selected from the group consisting of an alkylene group, an aralkylene group, an arylene group, and a cycloalkylene group.

2. 2. The organic-inorganic hybrid composition according to claim 1, wherein the molar ratio of the polymer chain ends is 1.0 mol % or more and 10 mol % or less relative to 100 mol % of all carbonate repeating units.

3. The organic-inorganic hybrid composition according to claim 1 or 2, wherein the formula (1) includes a structural unit represented by the following formula (3): 【Transformation 3】 (In formula (3), R ６ represents at least one group selected from the group consisting of a single bond, an alkylene group, an aralkylene group, an arylene group, and a cycloalkylene group.

4. 4. The organic-inorganic hybrid composition according to claim 1, wherein the polycarbonate resin has a carboxyl group content of 1 eq / ton to 200 eq / ton.

5. 5. The organic-inorganic hybrid composition according to claim 1, wherein the surfaces of the inorganic fine particles are modified with a surface modifying agent.

6. The organic-inorganic hybrid composition according to claim 5 , wherein the surface modifier has an acidic functional group.

7. 7. The organic-inorganic hybrid composition according to claim 6, wherein the acidic functional group is at least one acidic functional group selected from the group consisting of a sulfonic acid group, a phosphonic acid group, a phosphinic acid group, and a carboxylic acid group.

8. 8. The organic-inorganic hybrid composition according to claim 6, wherein the surfaces of the inorganic fine particles are modified with the surface modifying agent in an amount of 1 to 30% by mass based on the inorganic fine particles.

9. 9. The organic-inorganic hybrid composition according to claim 1, wherein the inorganic fine particles have an average particle size of 1 to 20 nm.

10. 10. The organic-inorganic hybrid composition according to claim 1, wherein the content of the inorganic fine particles is 1 to 50% by mass relative to the polycarbonate resin.

11. The inorganic fine particles are ZrO ２ The organic-inorganic hybrid composition according to any one of claims 1 to 10, wherein the organic-inorganic hybrid composition is zirconium oxide.

12. A molded article obtained by using the organic-inorganic hybrid composition according to any one of claims 1 to 11.

13. A film or sheet obtained by using the organic-inorganic hybrid composition according to any one of claims 1 to 11.

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