Polycarbonate resin, polycarbonate resin composition, optical component, and method for manufacturing polycarbonate resin

Abstract

To provide a polycarbonate resin and a polycarbonate resin composition which are excellent in releasability, and an optical component containing them.SOLUTION: A polycarbonate resin has a predetermined structural unit, where ratios of a macrocyclic structure in a fraction with a number average molecular weight Mn measured by MALDI-TOF-MS of 2,500 or more and less than 3,500, and in a fraction with a number average molecular weight Mn of 3,500 or more and less than 4,500 are 50 mol% or more, which are isolated by isolation GPC of the polycarbonate resin, respectively.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to polycarbonate resin, polycarbonate resin composition, optical components, and a method for producing polycarbonate resin. [Background technology]

[0002] In recent years, the proliferation of optical and information communication devices, including smartphones, has been rapid. For example, the camera functions of smartphones have become remarkably high-performance, and camera lenses are now required to be not only lightweight and low-cost, but also possess excellent optical properties such as superior heat resistance and low birefringence. To meet the requirements mentioned above, there is a great deal of activity in developing special polycarbonate resins for optical lenses.

[0003] For example, Patent Documents 1 to 5 disclose low birefringence special polycarbonate resins having bulky aromatic ring structures such as binaphthyl skeletons and fluorene skeletons. Specifically, Patent Documents 1 to 5 disclose polycarbonate resins that achieve low birefringence by controlling the content ratio of the bisphenol A skeleton, which has positive birefringence, and the aromatic ring structure, which has negative birefringence, in order to reduce the high birefringence of existing polycarbonates made of bisphenol A.

[0004] On the other hand, although not for optical lens applications, polycarbonate resins with aliphatic, particularly alicyclic, structures are also being developed as alternatives to aromatic polycarbonates. Alicyclic polycarbonates tend to have superior light resistance compared to polycarbonate resins containing aromatic rings such as bisphenol A. For example, Patent Document 6 discloses a polycyclic alicyclic polycarbonate resin that is excellent in transparency, heat resistance, and color tone. In addition to petroleum raw materials, the development of polycarbonate resins using raw materials derived from biomass such as plants is also underway. For example, in Patent Document 7, a polycarbonate resin using isosorbide that can be derived from starch as a raw material is disclosed.

[0005] Among the alicyclic polycarbonate resins disclosed in Patent Documents 6 and 7 above, poly(cyclohexene carbonate) having a cyclohexane carbonate structure is the simplest polycarbonate having a saturated six-membered carbon ring corresponding to the benzene ring. As shown in, for example, Patent Documents 8 and 9, it is widely known that the above poly(cyclohexene carbonate) can be synthesized by the reaction of cyclohexene oxide and carbon dioxide. Further, as described in Patent Documents 10 and Non-Patent Document 1, it is known that poly(cyclohexene carbonate) can be obtained by ring-opening polymerization of 1,2-cyclohexene carbonate.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Patent Document 10

[0007] [Non-Patent Document 1] Macromolecules 2014, 47, 4230-4235. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] However, previous literature disclosing poly(cyclohexene carbonate) has only evaluated the correlation between polymerization conditions and molecular weight, and has made little mention of the properties of poly(cyclohexene carbonate). In particular, its optical properties have not been mentioned at all.

[0009] The present inventors conducted a detailed examination of conventional polycarbonate resins, including those described in the above-mentioned prior art literature, and found that these polycarbonate resins have the problem of being insufficient in at least one of the optical properties, such as heat resistance and low birefringence.

[0010] For example, the polycarbonate resins having an aromatic ring structure described in Patent Documents 1 to 5 have the problem of insufficient optical properties such as low birefringence. Furthermore, the polycarbonate resin having a cyclohexane carbonate structure described in Patent Document 10 and Non-Patent Document 1 has the problem that, due to its low molecular weight, it is difficult to mold it into a film-like sample for optical measurement, and its optical properties are unknown.

[0011] To evaluate the optical properties of a resin, it is necessary to form it into a film of sufficient strength by operations such as hot pressing, and to be able to easily peel it off the substrate in the form of a self-supporting film after molding, i.e., to have excellent release properties. The inventors have found that the problem of obtaining a film-like molded article with sufficient strength can be solved by increasing the molecular weight of the polymer (Japanese Patent Application No. 2020-015754). This film also has good release properties, but the factors that improve such release properties have not been clarified.

[0012] The release properties of resin films have traditionally been thought to depend on the thermal stability of the resin. It is generally known that heterogeneous bonds at the molecular ends or in the main chain of polymers are the starting points for degradation. Therefore, polycarbonate resins containing cyclic components are being investigated from the perspective of suppressing such degradation and improving thermal stability.

[0013] For example, Patent Document 9 describes a poly(cyclohexene carbonate) cyclic material. However, it makes no mention of release properties, and the polycarbonate resin described in Patent Document 9 has the problem that its release properties are not sufficiently reliable.

[0014] Therefore, in view of the problems of the prior art described above, the present invention aims to provide a polycarbonate resin, a polycarbonate resin composition, and optical components containing the same, which have excellent mold release properties. [Means for solving the problem]

[0015] As a result of diligent research to solve the above problems, the inventors of the present invention have found that a polycarbonate resin having specific structural units and in which the proportion of macrocyclic structures within a predetermined number-average molecular weight range of Mn is greater than or equal to a predetermined value exhibits excellent mold release properties, thus completing the present invention. In other words, the present invention is as follows:

[0016] [1] A polycarbonate resin having a structural unit represented by the following formula (1), The compound includes a macrocyclic structure having two or more structural units represented by the following formula (1), with their terminals bonded to each other, and having a cyclic structure of 10 or more members. Fractions separated by preparative GPC of the polycarbonate resin, wherein the proportion of macrocyclic structures in fractions with a number-average molecular weight Mn of 2500 or more and less than 3500, as measured by MALDI-TOF-MS, is 80% or more, and the proportion of macrocyclic structures in fractions with a number-average molecular weight Mn of 3500 or more and less than 4500 is 70% or more. Polycarbonate resin (However, this excludes those containing chemical species that include ether bonds.) .

[0017] [ka]

[0018] (In formula (1), R 1 , R 2 , R 3 and R 4 Each of these is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, a carbon 1-10 alkoxy group, a carbon 1-11 ester group, a carbon 1-11 acyl group, or an unsubstituted linear, branched, or cyclic carbon 1-10 alkyl group, which may be bonded to each other via alkylene or carbonate groups to form a cyclic structure, and the alkylene group may be substituted with a hydroxyl group, a phosphate group, an amino group, an alkoxy group, or an ester group, and a carbonyl group may be inserted into the main chain.

[0019] [2] The aforementioned large ring structure is the polycarbonate resin described in [1], represented by the following formula (2).

[0020] [ka]

[0021] (In formula (2), R 1 , R 2 , R 3 and R 4Each is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, an alkoxy group having 1 to 10 carbon atoms, an ester group having 1 to 11 carbon atoms, an acyl group having 1 to 11 carbon atoms, or an unsubstituted linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, and may be bonded to each other via an alkylene group or a carbonate group to form a cyclic structure. The alkylene group may be substituted with a hydroxyl group, a phosphate group, an amino group, an alkoxy group or an ester group, and a carbonyl group may be inserted into the main chain. n is an integer of 0 or more.)

[0022] 〔3〕 The polycarbonate resin according to the above 〔1〕 or 〔2〕, wherein the weight average molecular weight in terms of polystyrene measured by size exclusion chromatography is 500,000 or less. 〔4〕 The polycarbonate resin according to any one of the above 〔1〕 to 〔3〕, an antioxidant, A polycarbonate resin composition containing. 〔5〕 An optical component containing the polycarbonate resin according to any one of the above 〔1〕 to 〔3〕, or the polycarbonate resin composition according to the above 〔4〕. 〔6〕 Use of the polycarbonate resin according to any one of the above 〔1〕 to 〔3〕, or the polycarbonate resin composition according to the above 〔4〕 for an optical component. 〔7〕 A method for producing the polycarbonate resin according to any one of the above 〔1〕 to 〔3〕, A method for producing a polycarbonate resin, which has a polymerization step of obtaining the polycarbonate resin by ring-opening polymerization of a cyclic carbonate represented by the following formula (3).

[0023]

Chemical formula

[0024] (In formula (3), R 1 , R 2 , R3 and R 4 Each of these is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, a carbon 1-10 alkoxy group, a carbon 1-11 ester group, a carbon 1-11 acyl group, or an unsubstituted linear, branched, or cyclic carbon 1-10 alkyl group, which may be bonded to each other via alkylene or carbonate groups to form a cyclic structure, and the alkylene group may be substituted with a hydroxyl group, a phosphate group, an amino group, an alkoxy group, or an ester group, and a carbonyl group may be inserted into the main chain.

[0025] [8] A method for producing a polycarbonate resin according to [7], wherein at least one selected from the group consisting of organolithium, organomagnesium, metal alkoxide, and metal amide is used as a polymerization initiator. [Effects of the Invention]

[0026] According to the present invention, it is possible to provide a polycarbonate resin with excellent mold release properties, a polycarbonate resin composition, and optical components containing the same. [Modes for carrying out the invention]

[0027] The embodiments for carrying out the present invention (hereinafter also referred to as "this embodiment") will be described in detail below. It should be noted that the present invention is not limited to this embodiment and can be implemented in various ways within the scope of its gist.

[0028] [Polycarbonate resin] The polycarbonate resin of this embodiment has a structural unit represented by the following formula (1), and the fractions separated by preparative gel permeation chromatography (also known as "preparative GPC") of the polycarbonate resin, wherein the proportion of macrocyclic structures in the fractions with a number average molecular weight Mn of 2500 or more and less than 3500, as measured by matrix-assisted laser desorption / ionization time-of-flight mass spectrometer (also known as "MALDI-TOF-MS"), and the fractions with a number average molecular weight Mn of 3500 or more and less than 4500, are each 50 mol% or more.

[0029] [ka]

[0030] (In formula (1), R 1 , R 2 , R 3 and R 4 Each of these is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, a carbon 1-10 alkoxy group, a carbon 1-11 ester group, a carbon 1-11 acyl group, or an unsubstituted linear, branched, or cyclic carbon 1-10 alkyl group, which may be bonded to each other via alkylene or carbonate groups to form a cyclic structure, and the alkylene group may be substituted with a hydroxyl group, a phosphate group, an amino group, an alkoxy group, or an ester group, and a carbonyl group may be inserted into the main chain.

[0031] In this specification, "carbonate group" means a divalent substituent represented by -OC(=O)O-.

[0032] (Large circular structure) In this specification, "macrocyclic structure" refers to a compound having a cyclic structure with 10 or more members. A macrocyclic structure is, for example, a compound having a macrocyclic structure in which two or more structural units represented by formula (1) are bonded to each other at their ends.

[0033] Generally, polycarbonate resins have substituents such as hydroxyl groups at their ends, which are thought to interact with the imide bonds in polyimides used as substrates for vacuum compression molding. Such interactions are thought to be stronger in lower molecular weight components with a larger number of terminal groups per unit molecular weight, and thus affect the release properties of the resin. Therefore, it is believed that increasing the proportion of macrocyclic structures without end groups in the low molecular weight components of polycarbonate resin will improve the mold release properties of the resin.

[0034] From the above viewpoint, in the polycarbonate resin of this embodiment, the proportion of macrocyclic structures in fractions separated by preparative GPC, where the number average molecular weight Mn measured by MALDI-TOF-MS is 2500 or more and less than 3500 (hereinafter sometimes referred to as "fraction with molecular weight 3000"), and in fractions where the number average molecular weight Mn is 3500 or more and less than 4500 (hereinafter sometimes referred to as "fraction with molecular weight 4000"), is 50 mol% or more. The proportion of macrocyclic structures in a fraction with a molecular weight of 3000 is preferably 60 mol% or more, more preferably 70 mol% or more, even more preferably 80 mol% or more, and even more preferably 80 mol% or more. The upper limit of the proportion of macrocyclic structures in a fraction with a molecular weight of 3000 is not particularly limited, but may be 100% or less, or 95% or less. The proportion of macrocyclic structures in a fraction with a molecular weight of 4000 is preferably 60 mol% or more, and more preferably 70 mol% or more. The upper limit of the proportion of macrocyclic structures in a fraction with a molecular weight of 4000 is not particularly limited, but may be 100% or less, or 95% or less.

[0035] The proportion of the aforementioned macrocyclic structures is measured by the following method. (i) The polycarbonate resin is prepared as a 30 mg / mL chloroform solution and fractionated into multiple fractions using a preparative GPC apparatus with chloroform as the mobile phase at a rate of 3.33 mL / min and retention times of 2 minutes. (ii) The fractions are analyzed by MALDI-TOF-MS, and the MALDI-TOF-MS results are analyzed using the software "Poyltool" to calculate the number-average molecular weight Mn. Fractions with Mn between 2500 and 3500 are classified as fractions with a molecular weight of 3000, and fractions with Mn between 3500 and 4500 are classified as fractions with a molecular weight of 4000. (iii) Prepare samples from which the solvent has been removed for the fractions with a molecular weight of 3000 and 4000. 1 The 1H-NMR spectrum is measured, and the proportion of macrocyclic structures is calculated from the following formula (A). The proportion of the macrocyclic structure (%) = (Ta - Tc) / Ta × 100 ... (A) Ta=( 1 (Integrated intensity ratio of protons in the main chain in the H-NMR spectrum / 2) / n n = Mn / Molecular weight of the repeating unit of polycarbonate resin (In the formula, Mn is the number-average molecular weight calculated from the results of MALDI-TOF-MS.) Tc= 1 The integral intensity ratio of terminal protons in the H-NMR spectrum / x (In the formula, x is the number of protons in the terminal group-derived peak.) In the measurement method described above, for example, the preparative GPC instrument is the "LC-908" manufactured by Nippon Analytical Engineering Co., Ltd. For the MALDI-TOF-MS instrument, for example, the "UltrafleXtreme" manufactured by Bruker is used. 1 For example, the NMR spectrometer manufactured by JEOL Ltd., product name "ECZ400S," can be used as the H-NMR measurement device. More specifically, the measurement and calculation can be performed by the method described in the examples below. The proportion of the macrocyclic structure can be controlled within the above numerical range by appropriately selecting the polymerization initiator and polymerization method described later.

[0036] The proportion of the fraction with a molecular weight of 3000 is preferably 0.01% to 20% by mass, more preferably 0.05% to 10% by mass, and even more preferably 0.1% to 5% by mass, relative to the total polycarbonate resin. The proportion of the fraction with a molecular weight of 4000 is preferably 0.01% to 30% by mass, more preferably 0.1% to 15% by mass, and even more preferably 0.5% to 5% by mass, relative to the total polycarbonate resin. The proportion of fractions with a molecular weight of 3000 and the proportion of fractions with a molecular weight of 4000 are measured by the following method. In the above-described method for measuring the proportion of macrocyclic structures, the solvent is removed from the fractions with a molecular weight of 3000 and 4000 separated in (i) and (ii), and their mass is measured. The proportion of each fraction is calculated from the total mass of the polycarbonate resin introduced into the preparative GPC apparatus.

[0037] The aforementioned large annular structure is preferably represented by the following formula (2).

[0038] [ka]

[0039] In formula (2), R 1 , R 2 , R 3 and R 4 Each of these is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, a carbon 1 to 10 alkoxy group, a carbon 1 to 11 ester group, a carbon 1 to 11 acyl group, or an unsubstituted linear, branched, or cyclic carbon 1 to 10 alkyl group, which may be bonded to each other via alkylene or carbonate groups to form a cyclic structure, and the alkylene group may be substituted with a hydroxyl group, a phosphate group, an amino group, an alkoxy group, or an ester group, and a carbonyl group may be inserted into the main chain, and n is an integer of 0 or more.

[0040] For example, Patent Document 9 describes poly(cyclohexene carbonate) rings, but chemical species with ether bonds different from carbonate bonds have been observed, and challenges remain in synthesizing polycarbonate rings that do not contain heterogeneous bonds that could serve as the starting point for thermal decomposition. The polycarbonate resin of this embodiment can have its heat resistance further improved by including a large annular structure having the structure shown in formula (2), thereby providing excellent mold release properties.

[0041] In addition to the effects described above, the polycarbonate resin and polycarbonate resin composition of this embodiment, by having the above configuration, also exhibit excellent optical properties such as moldability, heat resistance, and low birefringence. The factors contributing to this are thought to be as follows, but are not limited to these.

[0042] Conventional polycarbonate resins having an aromatic ring structure have the problem that, due to their structure, it is difficult to reduce birefringence. In contrast, the polycarbonate resin of this embodiment has the structural unit of formula (1) and therefore possesses excellent optical properties such as low birefringence. Furthermore, the presence of an alicyclic structure reduces the photoelastic coefficient, suppresses the occurrence of birefringence, and results in excellent optical properties. Moreover, because the structural unit of formula (1) has an alicyclic structure, it has excellent heat resistance.

[0043] In this embodiment, in formulas (1) and (2), R 1 ~R 4 Each of these is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, a carbon 1-10 alkoxy group, a carbon 1-11 ester group, a carbon 1-11 acyl group, or an unsubstituted linear, branched, or cyclic carbon 1-10 alkyl group. From the viewpoint of more effectively and reliably achieving the effects of the polycarbonate resin in this embodiment, in formulas (1) and (2), R 1 ~R 4Preferably, each substituent is independently selected from the group consisting of a hydrogen atom, a hydroxyl group, a vinyl group, an allyl group, a carbon 1 to 10 alkoxy group, a carbon 1 to 11 ester group, a carbon 1 to 11 acyl group, and an unsubstituted linear, branched, or cyclic carbon 1 to 10 alkyl group. From a similar viewpoint, in formulas (1) and (2) above, R 1 ~R 4 More preferably, each substituent is independently selected from the group consisting of a hydrogen atom, a hydroxyl group, a vinyl group, an allyl group, a carbon-1 to carbon-10 alkoxy group, and an unsubstituted linear, branched, or cyclic carbon-1 to carbon-10 alkyl group. From a similar viewpoint, in formulas (1) and (2) above, R 1 ~R 4 More preferably, each substituent is independently selected from the group consisting of a hydrogen atom, a hydroxyl group, a carbon-1 to carbon-10 alkoxy group, and an unsubstituted linear, branched, or cyclic carbon-1 to carbon-10 alkyl group. From a similar viewpoint, in formulas (1) and (2) above, R 1 ~R 4 More preferably, each substituent is independently selected from the group consisting of a hydrogen atom, a hydroxyl group, and an alkoxy group having 1 to 10 carbon atoms.

[0044] In this embodiment, in formulas (1) and (2), R 1 ~R 4 These groups may be bonded to each other via alkylene groups or carbonate groups (-OC(=O)O- groups) to form a cyclic structure, and the alkylene groups may be substituted with hydroxyl groups, phosphate groups, amino groups, alkoxy groups, or ester groups, and carbonyl groups may be inserted into the main chain. From the viewpoint of more reliably and effectively achieving the effects of the polycarbonate resin in this embodiment, R 1 ~R 4 However, when the alkylene groups are bonded to each other via alkylene groups to form a cyclic structure, the number of carbon atoms in the alkylene groups is preferably 1 to 10, more preferably 1 to 8, and even more preferably 1 to 6. Furthermore, from a similar viewpoint, the substituents on the alkylene group are preferably hydroxyl groups, alkoxy groups, or ester groups, and more preferably hydroxyl groups or alkoxy groups. From a similar perspective, R 1 ~R 4 If the compound forms a cyclic structure, it is preferably formed via an unsubstituted alkylene group or a carbonate group (-OC(=O)O- group). Examples of the unsubstituted alkylene group include a methylene group, an ethylene group, an n-propylene group, an n-butylene group, an n-pentylene group, and an n-hexylene group.

[0045] In the polycarbonate resin of this embodiment, the phosphate group and amino group in formulas (1) and (2) may be unsubstituted or substituted. That is, they may be monosubstituted phosphate groups and amino groups, or disubstituted phosphate groups and amino groups. In the polycarbonate resin of this embodiment, from the viewpoint of more effectively and reliably achieving excellent properties, when the phosphate group and amino group are substituted, the substituents are preferably unsubstituted linear, branched, or cyclic alkyl groups having 1 to 10 carbon atoms. From a similar viewpoint, the phosphate group and amino group are preferably unsubstituted.

[0046] The alkoxy groups having 1 to 10 carbon atoms in formulas (1) and (2) are not particularly limited, but examples include methoxy, ethoxy, propoxy, butoxy, pentyloxy, cyclopentyloxy, hexyloxy, cyclohexyloxy, heptyloxy, octyloxy, nonanyloxy, decyloxy, phenoxy, benzyloxy, vinyloxy, and allyloxy groups.

[0047] The ester groups having 1 to 11 carbon atoms in formulas (1) and (2) are not particularly limited, but examples include methyl ester group, ethyl ester group, propyl ester group, butyl ester group, pentyl ester group, cyclopentyl ester group, hexyl ester group, cyclohexyl ester group, heptyl ester group, octyl ester group, nonanyl ester group, decyl ester group, phenyl ester group, benzyl ester group, vinyl ester group, and allyl ester group.

[0048] The acyl group having 1 to 11 carbon atoms in formulas (1) and (2) is not particularly limited, but examples include the formyl group, acetyl group, propionyl group, butyryl group, valeryl group, and benzoyl group.

[0049] Examples of unsubstituted linear, branched, or cyclic C1-C10 alkyl groups in formulas (1) and (2) include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, cyclopentyl, n-hexyl, cyclohexyl, n-heptyl, n-octyl, n-nonanyl, and n-decyl groups.

[0050] (Average molecular weight of polycarbonate resin) In this embodiment, the polycarbonate resin preferably has a weight-average molecular weight (Mw) on a polystyrene basis, measured by size exclusion chromatography, of 1,000,000 or less. Having an Mw within this range facilitates molding and processing. Furthermore, such a polycarbonate resin exhibits superior heat resistance, optical properties, and release properties. From a similar viewpoint, the Mw is more preferably 800,000 or less, and even more preferably 500,000 or less. The Mw is preferably 10,000 or more, and more preferably 20,000 or more. In the polycarbonate resin of this embodiment, the number-average molecular weight (Mn) in terms of polystyrene, as measured by size exclusion chromatography, is preferably 1,000,000 or less. The polycarbonate resin of this embodiment exhibits superior molding properties, heat resistance, optical properties, and release properties when Mn is within the above range. From a similar viewpoint, Mn is more preferably 800,000 or less, and even more preferably 500,000 or less. Mn is preferably 5,000 or more, and more preferably 10,000 or more. The weight-average molecular weight and number-average molecular weight of polycarbonate resins can be measured by size exclusion chromatography, specifically by the method described in the examples.

[0051] In the polycarbonate resin of this embodiment, in order to control the weight-average molecular weight (Mw) and number-average molecular weight (Mn) within the above range, the ratio of polymerizable monomer, polymerization initiator, and additives can be appropriately adjusted, and the polycarbonate resin can be manufactured by the manufacturing method described later. Reducing the ratio of polymerization initiator to polymerizable monomer tends to increase Mw and Mn. In addition, increasing the polymerization time tends to increase Mw and Mn. Furthermore, stirring using a stirring blade tends to increase Mw and Mn.

[0052] The polycarbonate resin of this embodiment preferably does not contain chemical species including ether bonds. Since such heterogeneous bonds tend to be the starting point for thermal cleavage of the polymer main chain, it is thought that polymers that do not contain heterogeneous bonds can more significantly suppress the decrease in mold release properties due to thermal decomposition during film molding. Analysis is performed using MALDI-TOF-MS, and the presence or absence of chemical species containing ether bonds decarboxylated from carbonate is confirmed in the obtained MALDI-TOF-MS spectrum. If the ether-bonded species in the spectrum are below the detection limit, it is assumed that the sample does not contain chemical species containing ether bonds. Details of the measurement method are as described in the examples.

[0053] The method for synthesizing the polycarbonate resin in this embodiment is not particularly limited, but examples include copolymerizing an epoxide with carbon dioxide, ring-opening polymerization of a cyclic carbonate, and condensation polymerization of a diol with carbon dioxide or a carbonate ester. From the viewpoint of achieving the effects of the present invention more effectively and reliably, it is preferable to use the polycarbonate resin manufacturing method described later as the synthesis method for the polycarbonate resin in this embodiment.

[0054] [Polycarbonate resin composition] The polycarbonate resin composition of this embodiment contains the polycarbonate resin of this embodiment described above and an antioxidant.

[0055] The polycarbonate resin composition of this embodiment contains an antioxidant, which further prevents deterioration due to heat and shear during molding. Therefore, the heat resistance of the polycarbonate resin composition of this embodiment can be further improved. Furthermore, because the polycarbonate resin composition of this embodiment contains an antioxidant, oxidation of the polycarbonate resin during use can be further prevented, thereby further improving the light resistance of the polycarbonate resin composition.

[0056] The antioxidant in the polycarbonate resin composition of this embodiment is not particularly limited, but examples include hindered phenol-based antioxidants and phosphorus-based antioxidants.

[0057] Hindered phenol antioxidants are not particularly limited, but examples include Irganox 1010 (Irganox 1010: pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]), Irganox 1076 (Irganox 1076: octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate), and Irganox 1330 (Irganox 1330: 3,3',3'', 5,5',5''-Hexa-t-butyl-a,a',a''-(mesitylene-2,4,6-triyl)tri-p-cresol), Irganox 3114 (Irganox 3114: 1,3,5-Tris(3,5-di-t-butyl-4-hydroxybenzyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione), Irganox 3125 (Irganox 3125), Adekastab AO-60 (Pentaerythritol Tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]), Adekastab AO-80 (3,9-bis{2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxyoxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5.5]undecane), Cyanox 1790, Sumilizer GA-80, Sumilizer GS (2-[1-(2-hydroxy-3,5-di-tert-pentylphenyl)ethyl acrylate]-4,6-di-tert-pentylphenyl), and Sumilizer GM (Sumilizer GM: 2-tert-butyl-4-methyl-6-(2-hydroxy-3-tert-butyl-5-methylbenzyl)phenyl acrylate is an example. These can be used individually or in combination of two or more types.

[0058] Phosphorus-based antioxidants are not particularly limited, but examples include Irgafos168 (tris(2,4-di-t-butylphenyl) phosphite), Irgafos12 (tris[2-[[2,4,8,10-tetra-t-butyldibenzo[d,f][1,3,2]dioxaphosfepin-6-yl]oxy]ethyl]amine), ADKSTAB HP-10 (2,2'-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite), ADKSTAB PEP36 (bis(2,6-di-t-butyl-4-methylphenyl)pentaerythritol diphosphite), and ADKSTAB PEP36A (ADKSTAB Examples include PEP36A (bis(2,6-di-t-butyl-4-methylphenyl)pentaerythritol diphosphite), SumilizerGP ((6-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propoxy]-2,4,8,10-tetra-t-butyldibenz[d,f][1,3,2]dioxaphosfepine) and GSY P101 (tetrakis(2,4-di-t-butyl-5methylphenyl)4,4'-biphenylenediphosphonite). These can be used individually or in combination of two or more types.

[0059] From the viewpoint of more effectively and reliably achieving the effects of the present invention, the polycarbonate resin content in the polycarbonate resin composition of this embodiment is preferably 50% by mass or more and 100% by mass or less, more preferably 60% by mass or more and less than 100% by mass, and even more preferably 65% ​​by mass or more and less than 100% by mass, relative to the total polycarbonate resin composition.

[0060] The antioxidant content in the polycarbonate resin composition of this embodiment is preferably 0.001% by mass or more and 1% by mass or less, more preferably 0.003% by mass or more and 1% by mass or less, and even more preferably 0.005% by mass or more and 1% by mass or less, relative to the entire polycarbonate resin composition, from the viewpoint of further preventing deterioration due to heat and shear during molding.

[0061] The polycarbonate resin composition of this embodiment may contain other additives to the extent that they do not hinder the resolution of the problem of the present invention. Examples of additives, though not particularly limited, include 1,2-cyclohexene carbonate, 1,2-cyclohexanediol, toluene, o-xylene, m-xylene, p-xylene, methanol, ethanol, acetone, methyl ethyl ketone, methyl propyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, and acetic acid.

[0062] [Method for manufacturing polycarbonate resin] The method for producing polycarbonate resin according to this embodiment includes a polymerization step to obtain polycarbonate resin by ring-opening polymerization of a cyclic carbonate (A1) represented by the following formula (3). This step tends to increase the proportion of macrocyclic structures in the fractions with molecular weights of 3000 and 4000. Furthermore, this step can suppress the formation of ether bonds in the polycarbonate resin.

[0063] [ka]

[0064] In formula (3), R 1 ~R 4Each of these is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, a carbon 1 to 10 alkoxy group, a carbon 1 to 11 ester group, a carbon 1 to 11 acyl group, or an unsubstituted linear, branched, or cyclic carbon 1 to 10 alkyl group, which may be bonded to each other via an alkylene group or a carbonate group (-OC(=O)O- group) to form a cyclic structure, and the alkylene group may be substituted with a hydroxyl group, a phosphate group, an amino group, an alkoxy group, or an ester group, and a carbonyl group may be inserted into the main chain.

[0065] In this embodiment, the preferred R in formula (3) is 1 ~R 4 The same applies to the same components as in formula (1) above. Furthermore, the examples of phosphate groups, amino groups, C1-C10 alkoxy groups, C1-C11 ester groups, C1-C11 acyl groups, and unsubstituted linear, branched, or cyclic C1-C10 alkyl groups in formula (3) are also the same as those in formula (1) above.

[0066] In the method for producing polycarbonate resin of this embodiment, one type of cyclic carbonate may be used alone as the cyclic carbonate (A1) used for ring-opening polymerization, or R 1 ~R 4 Any combination of two or more cyclic carbonates with different properties may be used.

[0067] In the method for producing polycarbonate resin of this embodiment, the cyclic carbonate (A1) includes the cyclic carbonates (B1) to (B4) represented by the following formulas (4) to (7).

[0068] [ka]

[0069] [ka]

[0070] [ka]

[0071] [ka]

[0072] In equations (4) to (7) above, R 1 ~R 4 Each of these is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, a carbon 1-10 alkoxy group, a carbon 1-11 ester group, a carbon 1-11 acyl group, or an unsubstituted linear, branched, or cyclic carbon 1-10 alkyl group, which may be bonded to each other via an alkylene group or a carbonate group (-OC(=O)O- group) to form a cyclic structure, and the alkylene group may be substituted with a hydroxyl group, a phosphate group, an amino group, an alkoxy group, or an ester group, and a carbonyl group may be inserted into the main chain.

[0073] In this embodiment, the preferred R in formulas (4) to (7) is 1 ~R 4 The same applies to the same as in formula (1) above. Furthermore, the examples of phosphate groups, amino groups, C1-C10 alkoxy groups, C1-C11 ester groups, C1-C11 acyl groups, and unsubstituted linear, branched, or cyclic C1-C10 alkyl groups in formulas (4) to (7) above are the same as those in formula (1) above.

[0074] The method for synthesizing cyclic carbonate (A1) is not particularly limited, but for example, it can be obtained by reacting the corresponding diol (C1) represented by the following formula (8) with a formic halide ester or carbonate ester. The halogenated formic acid esters are not particularly limited, but examples include methyl chloroformate, ethyl chloroformate, methyl bromoformate, ethyl bromoformate, methyl iodoformate, and ethyl iodoformate. Examples of carbonate esters are not particularly limited, but include dimethyl carbonate, diethyl carbonate, dipropyl carbonate, dibutyl carbonate, dipentyl carbonate, dihexyl carbonate, diheptyl carbonate, dioctyl carbonate, dinonanyl carbonate, didecyl carbonate, diphenyl carbonate, and dibenzyl carbonate. The substituted hydrocarbon group may be linear, branched, or cyclic.

[0075] [ka]

[0076] In equation (8) above, R 1 ~R 4 Each of these is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, a carbon 1-10 alkoxy group, a carbon 1-11 ester group, a carbon 1-11 acyl group, or an unsubstituted linear, branched, or cyclic carbon 1-10 alkyl group, which may be bonded to each other via an alkylene group or a carbonate group (-OC(=O)O- group) to form a cyclic structure, and the alkylene group may be substituted with a hydroxyl group, a phosphate group, an amino group, an alkoxy group, or an ester group, and a carbonyl group may be inserted into the main chain.

[0077] Preferred R in formula (8) 1 ~R 4 The same applies to the same components as in formula (1) above. Furthermore, the examples of phosphate groups, amino groups, C1-C10 alkoxy groups, C1-C11 ester groups, C1-C11 acyl groups, and unsubstituted linear, branched, or cyclic C1-C10 alkyl groups in formula (8) are also the same as those in formula (1) above.

[0078] (Polymerization initiator) In the ring-opening polymerization step of cyclic carbonate (A1), a polymerization initiator may be used. Polymerization initiators are not particularly limited, but examples include acid catalysts, base catalysts, and enzyme catalysts. The base catalyst is not particularly limited, but examples include alkyl metals, metal alkoxides, metal amides, metal organic acid salts, cyclic amines such as cyclic monoamines and cyclic diamines (especially cyclic diamine compounds having an amidine skeleton), triamine compounds having a guanidine skeleton, and heterocyclic compounds containing a nitrogen atom. The alkyl metal is not particularly limited, but examples include organolithium such as methyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, and phenyllithium; organomagnesium such as methylmagnesium halide, ethylmagnesium halide, propylmagnesium halide, and phenylmagnesium halide; and organoaluminum such as trimethylaluminum and triethylaluminum. Among these, methyllithium, n-butyllithium, or sec-butyllithium are preferably used. The metal ions in the metal alkoxide are not particularly limited, but examples include alkali metals and alkaline earth metal ions, with alkali metals being preferred. The alkoxide ions are not particularly limited, but examples include methoxide, ethoxide, propoxide, butoxide, phenoxide, and benzyl oxide. Phenoxide and benzyl oxide may have substituents on the aromatic ring. The metal amide is not particularly limited, but examples include lithium amide, sodium amide, potassium amide, lithium hexamethyldisilazide (LiHMDS), sodium hexamethyldisilazide (NaHMDS), and potassium hexamethyldisilazide (KHMDS). The organic acid ion in the metal organic acid salt is not particularly limited, but examples include carboxylate ions having 1 to 10 carbon atoms. The metal in the metal organic acid salt is not particularly limited, but examples include lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, and tin. The base catalyst is not particularly limited, but examples include organic bases. The organic base is not particularly limited, but examples include 1,4-diazabicyclo-[2.2.2]octane (DABCO), 1,8-diazabicyclo[5.4.0]unde-7-ene (DBU), 1,5-diazabicyclo[4.3.0]nona-5-ene (DBN), 1,5,7-triazabicyclo[4.4.0]deca-5-ene (TBD), diphenylguanidine (DPG), N,N-dimethyl-4-aminopyridine (DMAP), imidazole, pyrimidine, and purine. From the viewpoint of achieving the effects of the present invention more effectively and reliably, the polymerization initiator in this embodiment is preferably an alkyl metal or metal alkoxide, and more preferably an alkali metal alkoxide containing tert-butoxide or n-butyllithium.

[0079] The alkali metal alkoxide or n-butyllithium used as a polymerization initiator may be in any associated state, such as monomer, dimer, trimer, or tetramer.

[0080] Furthermore, polymers having alcohol residues at the terminal end, such as polycaprolactone diol and polytetramethylene glycol, may be used as polymerization initiators for ring-opening polymerization of the cyclic carbonate (A1). This makes it possible to synthesize diblock or triblock copolymers.

[0081] In the polymerization step of the polycarbonate resin manufacturing method of this embodiment, the amount of polymerization initiator used may be appropriately adjusted according to the target molecular weight of the polycarbonate resin. When controlling the weight-average molecular weight (Mw) of the polycarbonate resin to a range of 500,000 or less from the viewpoint of improving moldability, heat resistance, optical properties, and release properties, the amount of polymerization initiator used is preferably 0.00001 moles to 5 moles, more preferably 0.0001 moles to 1 mole, and even more preferably 0.0001 moles to 0.5 moles, in terms of the amount of substance relative to the cyclic carbonate (A1), which is a ring-opening polymerizable monomer. Furthermore, the polymerization initiators described above may be used individually or in combination of two or more.

[0082] (Polymerization inhibitor) From the viewpoint of controlling the average molecular weight of the polycarbonate resin in this embodiment, a polymerization inhibitor may be used in addition to the polymerization initiator. Polymerization inhibitors are not particularly limited, but examples include inorganic and organic acids such as hydrochloric acid, sulfuric acid, nitric acid, methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, trifluoromethanesulfonic acid, phosphoric acid, metaphosphoric acid, formic acid, acetic acid, propionic acid, butyric acid, lactic acid, citric acid, ascorbic acid, gluconic acid, oxalic acid, tartaric acid, meldrumic acid, and benzoic acid.

[0083] (Additives) From the viewpoint of controlling the molecular weight of the resulting polymer and expressing various properties by controlling the terminal structure, in the manufacturing process of the polycarbonate resin of this embodiment, additives may be used in addition to the polymerization initiator. The additives are not particularly limited, but examples include methanol, ethanol, propanol, butanol, pentanol, cyclopentanol, hexanol, cyclohexanol, heptanol, nonanol, decanol, dodecanol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, 5-norbornene-2-methanol, 1-adamantanol, 2-adamantanol, trimethylsilylmethanol, phenol, benzyl alcohol, and p-methylbenzyl alcohol; monoalcohols such as ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexanediol, nonanediol, tetramethylene glycol, and polyethylene glycol; polyhydric alcohols such as glycerol, sorbitol, xylitol, ribitol, erythritol, and triethanolamine; and methyl lactate and ethyl lactate. Furthermore, the above-mentioned additives may be used individually or in combination of two or more types.

[0084] (Stirring) In the polycarbonate resin manufacturing method of this embodiment, it is preferable to stir the reactants and / or products during the polymerization step. Stirring during the polymerization step improves the uniformity of the system and increases the frequency of contact between the growing chains and monomers, which tends to allow for the production of a polycarbonate resin with a higher molecular weight. The stirring method is not particularly limited, but examples include stirring using a mechanical stirrer and a stirring blade, and stirring using a magnetic stirrer and a rotor. From the viewpoint of producing a polycarbonate resin with a higher molecular weight, it is more preferable to perform stirring in the polymerization step using a stirring blade.

[0085] (Reaction temperature) In the method for producing polycarbonate resin according to this embodiment, the reaction temperature in the polymerization step is not particularly limited as long as it is within the range that allows for the production of the polycarbonate resin of this embodiment, but is preferably -100°C to 150°C, more preferably -100°C to 100°C, and even more preferably -100°C to 80°C. By having the reaction temperature in the polymerization step within the above range, it becomes even easier to control the weight-average molecular weight of the resulting polycarbonate resin to a range of 500,000 or less.

[0086] (solvent) In the method for producing polycarbonate resin according to this embodiment, a solvent may or may not be used. The solvent is not particularly limited, but examples include ether-based solvents such as diethyl ether, diisopropyl ether, dibutyl ether, diphenyl ether, tetrahydrofuran (THF), 2-methyltetrahydrofuran, 1,4-dioxane, cyclopentyl methyl ether, tert-butyl methyl ether, and propylene glycol monomethyl ether acetate; halogen-based solvents such as methylene chloride, chloroform, dichloromethane, dichloroethane, and trichloroethane; saturated hydrocarbon-based solvents such as hexane, heptane, octane, nonane, cyclohexane, and methylcyclohexane; aromatic hydrocarbon-based solvents such as toluene, xylene, o-xylene, m-xylene, p-xylene, and cresol; and ketone-based solvents such as acetone, 2-butanone, 2-pentanone, 3-pentanone, cyclopentanone, cyclohexanone, and methyl isobutyl ketone.

[0087] [Optical components] The optical component of this embodiment is a molded article of the polycarbonate resin of this embodiment described above, or the polycarbonate resin composition of this embodiment described above, and contains these.

[0088] [Use as an optical component material] The polycarbonate resin and polycarbonate resin composition of this embodiment can be used as materials for various optical components. The polycarbonate resin, polycarbonate resin composition, and optical components containing them according to this embodiment have excellent heat resistance and light resistance, as well as excellent optical properties such as low birefringence, and can therefore be suitably used as various optical materials such as optical lens materials, optical devices, optical component materials, and display materials. The polycarbonate resin, polycarbonate resin composition, and optical components containing them according to this embodiment have excellent optical properties such as low birefringence, and are therefore particularly suitable for use in optical components that require low birefringence, such as camera lenses for smartphones. Furthermore, they have excellent heat resistance and light resistance, which can extend the lifespan of optical components. [Examples]

[0089] The present invention will be described in detail below using specific examples and comparative examples, but the present invention is not limited in any way by these examples.

[0090] Various measurements related to polycarbonate resin were performed as follows.

[0091] ( 1 H-NMR measurement) By performing NMR measurements using an NMR spectrometer (manufactured by JEOL Ltd., product name "ECZ400S") and a TFH probe as described below, the polycarbonate resin can be analyzed. 1 1H-NMR spectra were obtained. The reference peak for deuterated solvents was set at 7.26 ppm when using chloroform-d, and the measurement was performed with 32 cumulative measurements.

[0092] (Measurement of number-average molecular weight Mn and weight-average molecular weight Mw in polystyrene equivalent by size exclusion chromatography) A solution prepared by adding 2.0 g of tetrahydrofuran to 0.02 g of polycarbonate resin was used as the measurement sample. The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the polycarbonate resin were measured using a high-speed GPC instrument (manufactured by Tosoh Corporation, product name "HLC-8420GPC"). As columns, TSK Guard Columns SuperH-H, TSKgel SuperHM-H, TSKgel SuperHM-H, TSKgel SuperH2000, and TSKgel SuperH1000 (all product names of Tosoh Corporation) were connected in series and used. The column temperature was set to 40°C, and analysis was performed at a rate of 0.60 mL / min using tetrahydrofuran as the mobile phase. An RI detector was used as the detector. A calibration curve was created using polystyrene standard samples from Polymer Standards Service (molecular weights: 2,520,000, 1,240,000, 552,000, 277,000, 1,30,000, 66,000, 34,800, 19,700, 8,680, 3,470, 1,306, 370) as standard samples. Based on the calibration curve created in this manner, the number-average molecular weight Mn and weight-average molecular weight Mw of the polycarbonate resin were determined.

[0093] (Method for calculating the proportion of large ring structures) <(1) Fractionation and structural analysis> Polycarbonate resin was prepared as a 30 mg / mL chloroform solution and fractionated into multiple fractions at 2-minute intervals using a preparative GPC instrument (manufactured by Nippon Analytical Engineering Co., Ltd., product name "LC-908"). A JALGEL3H column (manufactured by Nippon Analytical Engineering Co., Ltd.) was used as the column, and analysis was performed at a rate of 3.33 mL / min with chloroform as the mobile phase.

[0094] <(2) Method for calculating the proportion of macrocyclic structures> The fractionated fractions were adjusted in the range of 1 mg / mL to 10 mg / mL, and solutions were prepared using tetrahydrofuran with 10 mg / mL of trans-2-[3-(4-tert-Butylphenyl)-2-methyl-2-propenylidene]malononitrile (DCTB) and 1 mg / mL of sodium trifluoroacetate. The fractionated fraction, trans-2-[3-(4-tert-Butylphenyl)-2-methyl-2-propenylidene]malononitrile (DCTB), and sodium trifluoroacetate were mixed in a volume ratio of 1:1:1, dropped onto a measurement plate, and air-dried to obtain the sample. This sample was analyzed using MALDI-TOF-MS (Bruker, product name "UltrafleXtreme"). The results of MALDI-TOF-MS were analyzed using the software "Poyltool" to calculate the number-average molecular weight (Mn) and weight-average molecular weight (Mw). Fractions with Mn between 2500 and 3500 were classified as fractions with a molecular weight of 3000, and fractions with Mn between 3500 and 4500 were classified as fractions with a molecular weight of 4000. Next, samples were prepared by removing the solvent from the fractions with a molecular weight of 3000 and 4000, and then using the method described above. 1 1H-NMR was measured. Based on these results, the proportion of macrocyclic structures was calculated using the following formula. Percentage of macrocyclic structures (%) = (Ta - Tc) / Ta × 100 Ta=( 1 (Integrated intensity ratio of protons in the main chain in the H-NMR spectrum / 2) / n n = Mn / Molecular weight of the repeating unit of polycarbonate resin (In the formula, Mn is the number-average molecular weight calculated from the results of MALDI-TOF-MS.) Tc= 1 The integral intensity ratio of terminal protons in the H-NMR spectrum / x (In the formula, x is the number of protons in the terminal group-derived peak.)

[0095] (Percentage of fractions with molecular weight 3000 and percentage of fractions with molecular weight 4000) In the "Method for Calculating the Proportion of Macrocyclic Structures" described above, the masses of the fractions with a molecular weight of 3000 and 4000 molecular weight, after removing the solvent, were measured, and the proportion of each fraction was calculated from the mass of the polycarbonate resin introduced into the preparative GPC apparatus.

[0096] (Presence or absence of ether bonds in polycarbonate resin) The fractions with molecular weights of 3000 and 4000 mentioned above were analyzed by MALDI-TOF-MS. The presence or absence of chemical species containing ether bonds decarboxylated from carbonates was confirmed by determining whether a peak with a mass 44 smaller than the peak detected at an intensity of 70% or more from the maximum intensity was observed in the obtained MALDI-TOF-MS spectrum (i.e., whether it was below the detection limit).

[0097] (Evaluation of moldability and release properties) First, an unstretched sample of polycarbonate resin was prepared using a vacuum compression molding machine. A laminate was obtained by placing polycarbonate resin in a polyimide frame with a thickness of 25 to 150 μm and sandwiching it between two polyimide films, two aluminum plates, and two iron plates. At this time, the laminate was constructed in the order of iron plate, aluminum plate, polyimide film, polyimide frame, polyimide film, aluminum plate, and iron plate. The laminate described above was placed in a vacuum compression molding machine (Shinto Metal Industries Co., Ltd., SFV-30 model), preheated at 210°C under reduced pressure (10kPa) for 5 minutes, and then compressed at 210°C under a press pressure of 10MPa for 10 minutes while maintaining the reduced pressure conditions. After releasing the reduced pressure and press pressure, the compressed laminate was transferred to a cooling compression molding machine (Shinto Metal Industries Co., Ltd., AYS-10 model) and cooled and solidified to obtain a pressed film with a thickness of 20 to 250 μm. Regarding moldability, a circle (○) was used if the material could be molded into a film, and a cross (×) was used if it could not be molded into a film. Regarding release properties, a "○" was given if the prepared film could be easily peeled off the polyimide film, and a "×" was given if it adhered closely to the polyimide film or was otherwise difficult to peel off.

[0098] [Example 1] The synthesized trans-cyclohexene carbonate (9.98 g, 70.2 mmol) was added to a 50 mL separable flask, and the flask was purged with nitrogen. The flask was immersed in a 25°C constant temperature bath, and 40.2 g of m-xylene was added to the flask. The mixture was stirred using a mechanical stirrer and a stirring blade to completely dissolve the monomer. Separately, potassium tert-butoxide solution (1.0 M, 115 μL, 0.115 mmol) and benzyl alcohol (0.127 g, 1.17 mmol) were weighed into a dry 30 mL Schlenk tube and diluted with 0.9 mL of m-xylene to prepare a polymerization initiator solution. While stirring the monomer solution, 0.34 mL of the prepared polymerization initiator solution was added and stirred at 25°C for 2 hours and 30 minutes. 0.0118 g of acetic acid was added to stop the reaction (polymerization solution). Subsequently, a reprecipitation operation was performed as follows to evaluate the methanol-insoluble portion. A sample of 6.97 g of the polymerization solution was taken and diluted with 8.03 g of m-xylene. The diluted solution was added to 157 g of methanol to precipitate the polymer. The precipitated polymer was recovered by vacuum filtration, and the resulting polymer was vacuum-dried at 100°C for 2 hours to obtain a homopolymer (1.19 g). After fractionation of the obtained homopolymer using preparative GPC, the proportion of macrocyclic structures was calculated for the fraction with a molecular weight of 3000 and the fraction with a molecular weight of 4000, as described above. Using the method described above, the proportions of macrocyclic structures in the fraction with a molecular weight of 3000 and the fraction with a molecular weight of 4000 were calculated to be 92 mol% and 75 mol%, respectively.

[0099] [Example 2] The synthesized trans-cyclohexene carbonate (9.98 g, 70.2 mmol) was added to a 50 mL separable flask, and the flask was purged with nitrogen. The flask was immersed in a 25°C constant temperature bath, 40.2 g of m-xylene was added to the flask, and the mixture was stirred using a mechanical stirrer and a stirring blade to completely dissolve the monomer. Separately, potassium tert-butoxide solution (1.0 M, 115 μL, 0.115 mmol) and benzyl alcohol (0.127 g, 1.17 mmol) were measured into a dried 30 mL Schlenk tube and diluted with 0.9 mL of m-xylene to prepare a polymerization initiator solution. While stirring the monomer solution, 0.34 mL of the prepared polymerization initiator solution was added, and the mixture was stirred at 25°C for 2 hours and 30 minutes. The reaction was stopped by adding 0.0118g of acetic acid (polymerization solution). Next, 0.205 g of benzoic anhydride and 0.904 mmol of 4-dimethylaminopyridine were weighed into a 50 mL three-necked flask. After purging the flask with nitrogen, 10.0 g of the polymerization solution was added to the flask. The flask was immersed in an oil bath and stirred at 100°C for 4 hours using a magnetic stirrer. After cooling, the solvent was removed using an evaporator, and then m-xylene (18.0 g) was added to the residue and dissolved. This solution was added to 200 mL of methanol, and the precipitated polymer was recovered by vacuum filtration and washed four times with 50 mL of methanol. The obtained polymer was vacuum dried at 100°C for 2 hours to obtain a double-ended modified polymer (1.28 g). Subsequently, in the same manner as in Example 1, the proportion of macrocyclic structures in the fraction with a molecular weight of 3000 and the fraction with a molecular weight of 4000 was calculated to be 86 mol% and 73 mol%, respectively.

[0100] [Example 3] The synthesized trans-cyclohexene carbonate (10.1 g, 71.2 mmol) was added to a 50 mL separable flask, and the flask was purged with nitrogen. The flask was immersed in a 25°C constant temperature bath, 40.2 g of m-xylene was added to the flask, and the mixture was stirred using a mechanical stirrer and a stirring blade to completely dissolve the monomer. Separately, potassium tert-butoxide solution (1.0 M, 0.28 mL, 0.28 mmol) and benzyl alcohol (0.063 g, 0.58 mmol) were measured into a dried 30 mL Schlenk tube and diluted with 2.6 mL of m-xylene to prepare a polymerization initiator solution. While stirring the monomer solution, 0.27 mL of the prepared polymerization initiator solution was added all at once and stirred at 25°C for 30 minutes. The reaction was stopped by adding 0.012g of acetic acid (polymerization solution). Next, to evaluate the methanol-insoluble content, a reprecipitation procedure was performed as follows. A 0.52 g sample of the polymerization solution was taken and diluted with 2.13 g of m-xylene. The diluted solution was added to 26.57 g of methanol to precipitate the polymer. The precipitated polymer was recovered by vacuum filtration, and the resulting polymer was vacuum-dried at 130°C for 2 hours to obtain a homopolymer (0.09 g). Subsequently, in the same manner as in Example 1, the proportion of macrocyclic structures in the fraction with a molecular weight of 3000 and the fraction with a molecular weight of 4000 was calculated to be 90 mol% and 74 mol%, respectively.

[0101] [Comparative Example 1] As Comparative Example 1, a poly(cyclohexene carbonate) resin synthesized by copolymerization of cyclohexene oxide and carbon dioxide (manufactured by Empower Materials, product name "QPAC130") was used. When vacuum compression molding was performed under the same conditions as in Example 1, it was observed that the thinnest edges of the film adhered closely to the Kapton substrate. When force was applied to peel it off, the film turned white, so the release properties were evaluated as ×. Comparative Example 1 was also fractionated using preparative GPC, and structural analysis was performed using MALDI-TOF-MS. The proportion of macrocyclic structures in the fractions with a molecular weight of 3000 and 4000 was calculated to be 0 mol% and 0 mol%, respectively. Polycarbonate structures with hydroxyl groups at both ends of the polymer were observed as assignable chemical species, while the macrocyclic structures observed in Example 1 were not observed. It is thought that the presence or absence of macrocyclic structures in low molecular weight components, where the influence of such interactions with terminal groups is significant, manifests as differences in the release properties of the polymer.

[0102] In the MALDI-TOF-MS spectra of the polycarbonate resins of Examples 1-3, no chemical species containing bonds other than carbonate bonds were observed as assignable peaks. On the other hand, in the polymer of Comparative Example 1, in addition to carbonate bonds, a peak corresponding to a mass-to-charge ratio corresponding to a structure with ether bonds decarboxylated from carbonate was observed, indicating that the polycarbonate resin contained ether bonds.

[0103] Table 1 shows the physical properties of the polycarbonate resins obtained in the examples and comparative examples.

[0104] [Table 1] [Industrial applicability]

[0105] The polycarbonate resin, polycarbonate resin composition, and optical components containing the same of the present invention have industrial applicability in various fields such as optical lens materials, optical devices, materials for optical components, and display materials.

Claims

1. A polycarbonate resin having a structural unit represented by the following formula (1), The compound includes a macrocyclic structure having two or more structural units represented by the following formula (1), with their terminals bonded to each other, and having a cyclic structure of 10 or more members. Fractions separated by preparative GPC of the polycarbonate resin, wherein the proportion of macrocyclic structures in fractions with a number average molecular weight Mn of 2500 or more and less than 3500, as measured by MALDI-TOF-MS, is 80% or more, and the proportion of macrocyclic structures in fractions with a number average molecular weight Mn of 3500 or more and less than 4500 is 70% or more. Polycarbonate resin (excluding those containing chemical species including ether bonds). 【Chemistry 1】 (In formula (1), R 1 , R 2 , R 3 and R 4 Each of these is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, a carbon 1 to 10 alkoxy group, a carbon 1 to 11 ester group, a carbon 1 to 11 acyl group, or an unsubstituted linear, branched, or cyclic carbon 1 to 10 alkyl group, which may be bonded to each other via alkylene or carbonate groups to form a cyclic structure, and the alkylene group may be substituted with a hydroxyl group, a phosphate group, an amino group, an alkoxy group, or an ester group, and a carbonyl group may be inserted into the main chain.

2. The polycarbonate resin according to claim 1, wherein the large annular structure is represented by the following formula (2). 【Chemistry 2】 (In formula (2), R 1 , R 2 , R 3 and R 4 Each of these is independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, a carbon 1 to 10 alkoxy group, a carbon 1 to 11 ester group, a carbon 1 to 11 acyl group, or an unsubstituted linear, branched, or cyclic carbon 1 to 10 alkyl group, which may be bonded to each other via alkylene or carbonate groups to form a cyclic structure, and the alkylene group may be substituted with a hydroxyl group, a phosphate group, an amino group, an alkoxy group, or an ester group, and a carbonyl group may be inserted into the main chain, where n is an integer of 0 or more.

3. The weight-average molecular weight in polystyrene terms, as measured by size exclusion chromatography, is 500,000 or less. The polycarbonate resin according to claim 1 or 2.

4. A polycarbonate resin according to any one of claims 1 to 3, Antioxidants, Contains Polycarbonate resin composition.

5. An optical component containing a polycarbonate resin according to any one of claims 1 to 3, or a polycarbonate resin composition according to claim 4.

6. Use of the polycarbonate resin according to any one of claims 1 to 3, or the polycarbonate resin composition according to claim 4, in optical components.

7. A method for producing a polycarbonate resin according to any one of claims 1 to 3, A method for producing a polycarbonate resin, comprising a polymerization step of obtaining the polycarbonate resin by ring-opening polymerization of a cyclic carbonate represented by the following formula (3). 【Transformation 3】 (In formula (3), R 1 , R 2 , R 3 and R 4 are each independently a hydrogen atom, a hydroxyl group, a phosphate group, an amino group, a vinyl group, an allyl group, an alkoxy group having 1 to 10 carbon atoms, an ester group having 1 to 11 carbon atoms, an acyl group having 1 to 11 carbon atoms, or an unsubstituted linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms, and may be bonded to each other via an alkylene group or a carbonate group to form a cyclic structure. The alkylene group may be substituted by a hydroxyl group, a phosphate group, an amino group, an alkoxy group, or an ester group, and a carbonyl group may be inserted into the main chain.)

8. At least one selected from the group consisting of organolithium, organomagnesium, metal alkoxides, and metal amides is used as a polymerization initiator. A method for producing polycarbonate resin according to claim 7.

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