Polycarbonate resin

Abstract

Provided is a terminal-modified polycarbonate resin having an ultraviolet-absorbing ability. More specifically, provided is a terminal-modified polycarbonate resin comprising a terminal structure (A) derived from a hydroxy compound represented by general formula (1) and a constituent unit (B) derived from a dihydric phenol compound. (In general formula (1), R1 represents an optionally branched C1-C6 alkyl group, R2 represents a halogen atom, a hydroxy group, or an optionally substituted phenylthio group, and n indicates an integer of 0-4.)

Description

Polycarbonate resin

[0001] The present invention relates to a novel terminal-modified polycarbonate resin.

[0002] Polycarbonate resin compositions are extremely useful materials because they have high total light transmittance, high impact strength, and high molding stability. Polycarbonate resin compositions are applicable to a variety of applications, including transparent substrates for optical materials, automotive parts, and coatings. They are particularly suitable as molding materials for outdoor use, such as camera lenses, eyeglass lenses, and sunglasses. However, molded products made from synthetic resins containing polycarbonate resins are prone to deterioration and yellowing upon long-term exposure to sunlight and ultraviolet light. Therefore, ultraviolet absorbers are sometimes incorporated to improve light resistance (Patent Documents 1 and 2). Polycarbonates containing triazole- or benzophenone-type ultraviolet absorbers at the terminal end are also known (Patent Document 3). However, while these ultraviolet absorbers exhibit excellent weather resistance, they have low activity as reactive groups, making them unsuitable for use as raw materials for producing block copolymers with other resins or as reactive resin modifiers.

[0003] Known examples of terminally modified polycarbonate resins include a terminally modified polycarbonate oligomer terminated with a chalcone derivative (Patent Document 4) and a polycarbonate resin having a terminal group with a specific structure having a benzotriazole ring (Patent Document 5). However, the development of further terminally modified polycarbonate resins is desired.

[0004] WO 2020 / 175487WO 2020 / 137819 JP-A-49-99596 JP-A-6-256493 JP-A-9-316187

[0005] There is a need for the development of novel terminal-modified polycarbonate resins with excellent ultraviolet absorption capabilities.

[0006] As a result of extensive research, the present inventors have developed a novel terminally modified polycarbonate resin having excellent ultraviolet absorbing ability, thereby completing the present invention.

[0007] That is, the present invention includes the following embodiments: <1> A terminal-modified polycarbonate resin containing a terminal structure (A) derived from a hydroxy compound represented by general formula (1) and a structural unit (B) derived from a dihydric phenol compound. (In the above general formula (1), R １ represents an alkyl group having 1 to 6 carbon atoms which may be branched, and R ２ represents a halogen, a hydroxy group, or a phenylthio group which may have a substituent, and n represents an integer of 0 to 4.) <2> The terminally modified polycarbonate resin according to <1>, wherein the hydroxy compound represented by general formula (1) is a compound represented by any one of the following formulas (1-1), (1-2), and (1-3), or a combination of two or more of these compounds: <3> The terminal-modified polycarbonate resin according to <1>, wherein the dihydric phenol compound is a compound represented by the following general formula (2): (In the formula, R ５ ~R ８ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, and X is -O-, -S-, -SO-, -SO ２ -, -CO-, or a divalent group represented by any one of the following general formulas (3) to (6): (In general formulas (3) to (6), R ９ and R １０ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or ９ and R １０ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; c represents an integer of 0 to 20; R １１ and R１２ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or １１ and R １２ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; R １３ ~R １６ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or １３ and R １４ and R １５ and R １６ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; R １７ ~R ２６ each independently represents hydrogen or an alkyl group having 1 to 3 carbon atoms; R １７ ~R ２６at least one of which is an alkyl group having 1 to 3 carbon atoms.) <4> The terminally-modified polycarbonate resin according to <3>, in which X is a divalent group represented by general formula (3). <5> The terminally-modified polycarbonate resin according to <3>, in which the dihydric phenol compound is a bisphenol compound. <6> The terminally-modified polycarbonate resin according to <5>, in which the bisphenol compound is selected from the group consisting of bisphenol A, bisphenol AP, bisphenol Z, bisphenol CD, bisphenol C, bisphenol IOTD, bisphenol IBTD, and bisphenol MIBK. <7> The terminally-modified polycarbonate resin according to <6>, in which the bisphenol compound is bisphenol A. <8> The terminally-modified polycarbonate resin according to <7>, in which the hydroxy compound represented by general formula (1) is a compound represented by any one of the following formulas (1-1), (1-2), or (1-3), or a combination of two or more of these compounds: <9> The terminally-modified polycarbonate resin according to <1>, having a viscosity average molecular weight of 10,000 to 60,000. <10> The terminally-modified polycarbonate resin according to <1>, having the terminal structure (A) in an amount of 0.5 mass% or more relative to the structural unit (B) derived from a dihydric phenol compound. <11> The terminally-modified polycarbonate resin according to <1>, characterized in that the transmittance at 330 nm is 1% or less. <12> An optical material comprising the terminally-modified polycarbonate resin according to <1>. <13> An optical material comprising the terminally-modified polycarbonate resin according to <8>.

[0008] According to the present invention, a novel terminally modified polycarbonate resin having excellent ultraviolet absorbing ability can be obtained.

[0009] The present invention will be described in detail below.

[0010] 1. Terminally modified polycarbonate resin The present invention relates to a terminally modified polycarbonate resin containing a terminal structure (A) derived from a hydroxy compound represented by general formula (1) and a structural unit (B) derived from a dihydric phenol compound: (In the above general formula (1), R １represents an alkyl group having 1 to 6 carbon atoms which may be branched, and R ２ represents a halogen atom, a hydroxy group, or a phenylthio group which may have a substituent, and n represents an integer of 0 to 4.

[0011] In one embodiment of the present invention, the hydroxy compound represented by the general formula (1) may be a compound represented by any one of the following formulas (1-1), (1-2), or (1-3), or a combination of two or more of these compounds. In one embodiment of the present invention, there is provided a terminally modified polycarbonate resin, in which the hydroxy compound represented by the general formula (1) is a compound represented by any one of the following formulas (1-1), (1-2), or (1-3), or a combination of two or more of these compounds.

[0012] In one embodiment of the present invention, there is provided a terminally-modified polycarbonate resin in which the hydroxy compound represented by the general formula (1) is a compound represented by the formula (1-1). In one embodiment of the present invention, there is provided a terminally-modified polycarbonate resin in which the hydroxy compound represented by the general formula (1) is a compound represented by the formula (1-2). In one embodiment of the present invention, there is provided a terminally-modified polycarbonate resin in which the hydroxy compound represented by the general formula (1) is a compound represented by the formula (1-3). In one embodiment of the present invention, there is provided a terminally-modified polycarbonate resin in which the hydroxy compound represented by the general formula (1) is a combination of a compound represented by the formula (1-1) and a compound represented by the formula (1-2). In one embodiment of the present invention, there is provided a terminally-modified polycarbonate resin in which the hydroxy compound represented by the general formula (1) is a combination of a compound represented by the formula (1-1) and a compound represented by the formula (1-3). In one embodiment of the present invention, there is provided a terminally-modified polycarbonate resin in which the hydroxy compound represented by the general formula (1) is a combination of a compound represented by the general formula (1-2) and a compound represented by the general formula (1-3). In one embodiment of the present invention, there is provided a terminally-modified polycarbonate resin in which the hydroxy compound represented by the general formula (1) is a combination of a compound represented by the general formula (1-1), a compound represented by the general formula (1-2), and a compound represented by the general formula (1-3).

[0013] In one embodiment of the present invention, there is provided a terminal-modified polycarbonate resin, wherein the dihydric phenol compound is a compound represented by the following general formula (2): (In the formula, R ５ ~R ８ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, and X is -O-, -S-, -SO-, -SO ２-, -CO-, or a divalent group represented by any one of the following general formulas (3) to (6): (In general formulas (3) to (6), R ９ and R １０ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or ９ and R １０ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; c represents an integer of 0 to 20; R １１ and R １２ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or １１ and R １２ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; R １３ ~R １６ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or １３ and R １４ and R １５ and R １６ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; R １７ ~R ２６ each independently represents hydrogen or an alkyl group having 1 to 3 carbon atoms; R １７ ~R ２６ At least one of the groups is an alkyl group having 1 to 3 carbon atoms.

[0014] The terminally modified polycarbonate resin of the present invention may be a terminally modified polycarbonate resin having a constituent unit represented by the following general formula (I), the terminal group of which is represented by the terminal structure (A) derived from the hydroxy compound represented by the above general formula (1). (In the formula, R ５ ~R ８ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, and X is -O-, -S-, -SO-, -SO ２ -, -CO-, or a divalent group represented by any one of the following general formulas (3) to (6): (In general formulas (3) to (6), R ９ and R １０ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or ９ and R １０ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; c represents an integer of 0 to 20; R １１ and R １２ each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or １１ and R １２ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; R １３ ~R １６each independently represents hydrogen, halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or １３ and R １４ and R １５ and R １６ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; R １７ ~R ２６ each independently represents hydrogen or an alkyl group having 1 to 3 carbon atoms; R １７ ~R ２６ At least one of the groups is an alkyl group having 1 to 3 carbon atoms.

[0015] In one embodiment of the present invention, X in the structural unit represented by the general formula (I) may be a divalent group represented by the general formula (3). In one embodiment of the present invention, there is provided a terminally modified polycarbonate resin in which X is a divalent group represented by the general formula (3).

[0016] In one embodiment of the present invention, the dihydric phenol compound may be a bisphenol compound. In one embodiment of the present invention, there is provided a terminal-modified polycarbonate resin, in which the dihydric phenol compound is a bisphenol compound.Examples of bisphenol compounds used as the dihydric phenol compound in the present invention include 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane, 2,2-bis(4-hydroxy-3-bromophenyl)propane, 2,2-bis(4-hydroxy-3-chlorophenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, and 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane. bisphenol A; BPA), 1,1-bis(4-hydroxyphenyl)-1-phenylethane, bis(4-hydroxyphenyl)diphenylmethane, α,ω-bis[3-(O-hydroxyphenyl)propyl]polydimethylsiloxane, 2,2-bis(4-hydroxyphenyl)propane (bisphenol A; BPA), 1,1-bis(4-hydroxyphenyl)-1-phenylethane (bisphenol AP), 2,2-bis(4-hydroxyphenyl)butane (bisphenol B; BPB), bis(4-hydroxyphenyl)diphenylmethane Bisphenol BP, Bisphenol CD, 2,2-bis(3-methyl-4-hydroxyphenyl)propane (Bisphenol C), 1,1-bis(4-hydroxyphenyl)ethane (Bisphenol E), Bis(4-hydroxyphenyl)methane (Bisphenol F), 2,2-bis(4-hydroxy-3-isopropylphenyl)propane (Bisphenol G), 1,1-bis(4-hydroxyphenyl)-2-ethylhexane (Bisphenol IOTD), 1,1-bis(4-hydroxyphenyl)-2- Bisphenols include, but are not limited to, methylpropane (bisphenol IBTD), 1,1-bis(4-hydroxyphenyl)-2-methylpentane (bisphenol MIBK), 5,5'-(1-methylethylidene)-bis[1,1'-(bisphenyl)-2-ol]propane (bisphenol PH), 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane (bisphenol TMC), and 1,1-bis(4-hydroxyphenyl)cyclohexane (bisphenol Z; BPZ).

[0017] In a preferred embodiment of the present invention, the bisphenol compound may be selected from the group consisting of bisphenol A, bisphenol AP, bisphenol Z, bisphenol CD, bisphenol C, bisphenol IOTD, bisphenol IBTD, and bisphenol MIBK. In one embodiment of the present invention, there is provided a terminal-modified polycarbonate resin in which the bisphenol compound is selected from the group consisting of bisphenol A, bisphenol AP, bisphenol Z, bisphenol CD, bisphenol C, bisphenol IOTD, bisphenol IBTD, and bisphenol MIBK. In a more preferred embodiment of the present invention, there is provided a terminal-modified polycarbonate resin in which the bisphenol compound is bisphenol A. In one embodiment of the present invention, the dihydric phenol compounds may be used alone or in combination of two or more.

[0018] In a more preferred embodiment of the present invention, there is provided a terminally modified polycarbonate resin in which the bisphenol compound is bisphenol A, and the hydroxy compound represented by general formula (1) is a compound represented by any one of the following formulas (1-1), (1-2), or (1-3), or a combination of two or more of these compounds:

[0019] Monohydric phenols (also referred to as "terminal terminators A"), which are precursors of the structure represented by the terminal structure (A) derived from the hydroxy compound represented by the general formula (1), are readily available on the market as ultraviolet absorbers. In one embodiment of the present invention, the monohydric phenols may be used alone or in combination of two or more.

[0020] In one embodiment of the present invention, the terminal structure (A) derived from the hydroxy compound represented by the general formula (1) is contained in an amount of 0.5% by mass or more. In one embodiment of the present invention, it may be contained in an amount of preferably 0.5% by mass to 15% by mass relative to the structural unit (B) derived from the dihydric phenol compound. The terminal structure (A) derived from the hydroxy compound represented by the general formula (1) may be contained in an amount of more preferably 1% by mass to 10% by mass, even more preferably 2% by mass to 10% by mass, and particularly preferably 3% by mass to 7% by mass relative to the structural unit (B) derived from the dihydric phenol compound.

[0021] In one embodiment of the present invention, the terminally modified polycarbonate resin may have any of a random copolymer structure, a block copolymer structure, and an alternating copolymer structure.

[0022] In one embodiment of the present invention, the terminal-modified polycarbonate resin can be blended with other resins to form a terminal-modified polycarbonate resin composition, such as, but not limited to, polyamide, polyacetal, polycarbonate, modified polyphenylene ether, polyethylene terephthalate, and polybutylene terephthalate.

[0023] In one embodiment of the present invention, the terminal-modified polycarbonate resin can be made into a terminal-modified polycarbonate resin composition by adding an antioxidant and a mold release agent as additives.

[0024] Examples of antioxidants include triethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert- butyl-4-hydroxybenzyl)benzene, N,N-hexamethylenebis(3,5-di-tert-butyl-4-hydroxy-hydrocinnamide), 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, and 3,9-bis{1,1-dimethyl-2-[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl}-2,4,8,10-tetraoxaspiro(5,5)undecane.

[0025] The content of the antioxidant in the terminally modified polycarbonate resin composition is preferably 0.50% by mass or less, more preferably 0.10 to 0.40% by mass, and particularly preferably 0.20 to 0.40% by mass.

[0026] Preferably, the release agent is one that comprises 90% by mass or more of an ester of an alcohol and a fatty acid. Specific examples of the ester of an alcohol and a fatty acid include an ester of a monohydric alcohol and a fatty acid, and a partial or complete ester of a polyhydric alcohol and a fatty acid. The ester of a monohydric alcohol and a fatty acid is preferably an ester of a monohydric alcohol having 1 to 20 carbon atoms and a saturated fatty acid having 10 to 30 carbon atoms. Furthermore, the partial or complete ester of a polyhydric alcohol and a fatty acid is preferably a partial or complete ester of a polyhydric alcohol having 1 to 25 carbon atoms and a saturated fatty acid having 10 to 30 carbon atoms.

[0027] Specific examples of esters of monohydric alcohols and saturated fatty acids include stearyl stearate, palmityl palmitate, butyl stearate, methyl laurate, isopropyl palmitate, etc. Examples of partial or full esters of polyhydric alcohols and saturated fatty acids include stearic acid monoglyceride, stearic acid monoglyceride, stearic acid diglyceride, stearic acid triglyceride, stearic acid monosorbitate, behenic acid monoglyceride, capric acid monoglyceride, lauric acid monoglyceride, pentaerythritol monostearate, pentaerythritol tetrastearate, pentaerythritol tetrapelargonate, propylene glycol monostearate, biphenyl biphenate, sorbitan monostearate, 2-ethylhexyl stearate, and full or partial esters of dipentaerythritol such as dipentaerythritol hexastearate.

[0028] The content of the release agent in the terminally modified polycarbonate resin composition is preferably 0.50% by mass or less, more preferably 0.01 to 0.10% by mass, and particularly preferably 0.03 to 0.05% by mass.

[0029] Furthermore, other additives such as a processing stabilizer, an ultraviolet absorber, a flowability modifier, a crystal nucleating agent, a reinforcing agent, a dye, an antistatic agent, a bluing agent, and an antibacterial agent may be added to the terminally modified polycarbonate resin composition of the present invention.

[0030] 2. Method for Producing Terminally Modified Polycarbonate Resin In one embodiment of the present invention, the terminally modified polycarbonate resin can be produced by the same method as the method for producing conventional polycarbonate resins, except that a terminal terminator is used.

[0031] Specifically, the interfacial polymerization method involves reacting a dihydric phenol compound with phosgene in the presence of an inert organic solvent or an aqueous alkali solution, followed by adding a terminal terminator and a polymerization catalyst such as a tertiary amine or a quaternary ammonium salt to polymerize, while the pyridine method involves dissolving a dihydric phenol compound and a terminal terminator in pyridine or a mixed solution of pyridine and an inert solvent, and then blowing in phosgene to directly obtain a polycarbonate oligomer. Note that the interfacial polymerization method may also involve adding the terminal terminator during the reaction of the dihydric phenol compound with phosgene.

[0032] 3. Physical Properties of Terminally Modified Polycarbonate Resin The terminally modified polycarbonate resin of the present invention was evaluated for the following physical properties.

[0033] (A) Viscosity Average Molecular Weight (Mv) In one embodiment of the present invention, the viscosity average molecular weight (Mv) of the terminally modified polycarbonate resin may preferably be 10,000 to 60,000. In one embodiment of the present invention, a terminally modified polycarbonate resin having a viscosity average molecular weight of 10,000 to 60,000 is provided. The viscosity average molecular weight (Mv) of the terminally modified polycarbonate is more preferably 13,000 to 50,000, even more preferably 15,000 to 40,000, even more preferably 20,000 to 35,000, and particularly preferably 25,300 to 33,500. When the viscosity average molecular weight (Mv) of the polycarbonate is within the above range, it is possible to prevent the molded article from becoming brittle, to prevent the melt viscosity from becoming excessively high, thereby facilitating removal of the resin after production, and to improve fluidity, thereby facilitating injection molding in a molten state.

[0034] The viscosity average molecular weight (Mv) was measured under the following conditions: measuring instrument: Ubbelohde capillary viscometer, solvent: dichloromethane, resin solution concentration: 0.5 g / dL, and measuring temperature: 25°C. The intrinsic viscosity [η] deciliters / gram was determined with a Huggins constant of 0.45, and calculated using the following formula: η = 1.23 × 10 -4 ×Mv 0.83

[0035] (B) Wavelength at which transmittance is 0% and transmittance at 330 nm In the present invention, the higher the wavelength at which transmittance is 0%, the better. A high wavelength at which transmittance is 0% means that transmittance is high over a wide wavelength range. In particular, for applications requiring a light substrate, such as optical materials, a high transmittance over a wide wavelength range is more beneficial. For the terminally modified polycarbonate resin of the present invention, the transmittance at wavelengths from 850 nm to 200 nm was measured to determine the wavelength at which transmittance is 0%. In one embodiment of the present invention, the terminally modified polycarbonate resin may have a transmittance at 330 nm of 1% or less. In one embodiment of the present invention, a terminally modified polycarbonate resin characterized by a transmittance at 330 nm of 1% or less is provided. The transmittance at 330 nm of the terminally modified polycarbonate resin of the present invention may be preferably 0.5% or less, more preferably 0.1% or less. If the transmittance at 330 nm is within the above range, the terminally modified polycarbonate resin can be used in practical applications, combining excellent ultraviolet absorption ability and light stability.

[0036] The transmittance was obtained by measuring the transmittance of the resin solution under the following conditions: Measuring instrument: Shimadzu Corporation UV-1280 ultraviolet-visible spectrophotometer Solvent: dichloromethane Resin solution concentration: 10 w / w% Cell: 1 cm quartz cell Photometric mode Zero point correction at 330 nm was performed using dichloromethane solvent Measurement wavelength range: 850 nm to 200 nm

[0037] (C) Weight Loss Temperature (°C) and Weight Loss Temperature Range (°C) The temperatures at which the mass decreased by 10%, 15%, 20%, 30%, and 50% were measured using a thermogravimetric differential thermal analyzer (TG / DTA). The higher the weight loss temperature (°C), the higher the heat resistance. Apparatus: TGA8000 manufactured by PerkinElmer Japan. Measurement sample: A 5 mg test piece was weighed and placed on a platinum pan. Measurement: Performed under a nitrogen atmosphere (nitrogen flow rate: 40 ml / min). The sample temperature was adjusted to 50°C and then increased to 550°C at 10°C / min.

[0038] The weight loss temperature range (°C) was calculated as follows. A smaller weight loss temperature range (°C) means that thermal decomposition occurs more rapidly, and it can be said that the thermal decomposition behavior is stable. When the weight loss temperature range (°C) is small, the transparency of the molded body is sufficiently high and the conditions required for optical materials are met, making it easier to determine the intended use and to deal with thermal decomposition of the molded body. "10→15% mass loss temperature range (°C)": temperature at which the mass decreases by 15% minus the temperature at which the mass decreases by 10% "15→20% mass loss temperature range (°C)": temperature at which the mass decreases by 20% minus the temperature at which the mass decreases by 15% "20→30% mass loss temperature range (°C)": temperature at which the mass decreases by 30% minus the temperature at which the mass decreases by 20% "30→50% mass loss temperature range (°C)": temperature at which the mass decreases by 50% minus the temperature at which the mass decreases by 30% "50→10% mass loss temperature range (°C)": temperature at which the mass decreases by 50% minus the temperature at which the mass decreases by 10%

[0039] (D) Adhesion Evaluation (Cross-Cut Test) A 10 wt% dichloromethane solution of polycarbonate resin was prepared and coated onto a stainless steel plate so that the coating thickness would be 60 μm. After coating, the coating was air-dried for 24 hours and then dried at 120° C. for 24 hours to remove the dichloromethane, and a laminate having a coating film made of polycarbonate resin laminated thereon was produced.

[0040] The obtained laminate was subjected to an adhesion test in accordance with JIS K5600-5-6, using a 24 mm wide Cellotape (registered trademark) manufactured by Nichiban Co., Ltd., in accordance with the cross-cut test method (at 1 mm intervals), and the adhesion was evaluated by classifying the adhesiveness into numerical values ​​from 0 (no peeling) to 5 (almost complete peeling) based on the JIS classification index. The less peeling there was, the higher the adhesion. The less peeling there was, the more suitable it was for applications such as coatings.

[0041] (E) Gas generation during molding Using a Sumitomo Heavy Industries SE7M, cylinder temperature set at 280°C, a teardrop-shaped mold was used, and after 500 shots were molded at a mold temperature set at 80°C, photographs of the deposits on the mold were taken with a KEYENCE VHX-970F digital microscope and observed. The amount of gas generated from the molten polycarbonate resin was evaluated as follows: high (×), low (△), and no gas was observed (◯).

[0042] (F) Generation of mold deposits The molds used in the test in 5) above were visually inspected for deposits. Those with a large amount of deposits were evaluated as x, those with a small amount as △, and those with no deposits observed as ◯.

[0043] 4. Optical Materials Comprising Terminally Modified Polycarbonate Resin The terminally modified polycarbonate resin of the present invention can be used in a variety of applications, such as transparent substrate applications for optical materials, automotive parts applications, and coating films, and is particularly suitable as a molding material for outdoor use, such as lenses for cameras, eyeglasses, and sunglasses.

[0044] In one embodiment of the present invention, there is provided an optical material comprising a terminal-modified polycarbonate resin that includes a terminal structure (A) derived from a hydroxy compound represented by general formula (1) and a structural unit (B) derived from a dihydric phenol compound. (In the above general formula (1), R １ represents an alkyl group having 1 to 6 carbon atoms which may be branched, and R ２ represents a halogen, a hydroxy group, or a phenylthio group which may have a substituent, and n represents an integer of 0 to 4.

[0045] In a more preferred embodiment of the present invention, there is provided an optical material comprising a terminally modified polycarbonate resin in which the bisphenol compound is bisphenol A, and the hydroxy compound represented by the general formula (1) is a compound represented by any one of the following formulas (1-1), (1-2), or (1-3), or a combination of two or more of these compounds:

[0046] The present invention will be described below using examples, but it is not intended that the present invention be limited by these examples.

[0047] <Production of Terminally Modified Polycarbonate Resin and Analysis of Physical Properties> Terminally modified polycarbonate resin was produced according to the method described below, and the viscosity average molecular weight (Mv), 330 nm transmittance, and infrared absorption (IR) spectrum of the obtained resin were analyzed.

[0048] <Synthesis Example of Hydroxy Compound Represented by General Formula (1)> <Synthesis Example of Compound (1-1)> 2-(5-Chloro-2-benzotriazolyl)-6-tert-butyl-p-cresol (50.0 g, 158.3 mmol), 4-hydroxybenzenethiol (40.0 g, 316.6 mmol), potassium carbonate (48.2 g, 348.4 mmol), and potassium iodide (1.84 g, 11.08 mmol) were reacted in 125.0 g of DMF at 125° C. for 15 hours. After completion of the reaction, the pH was adjusted, filtered, washed with MeOH, washed with water, and purified by recrystallization to obtain compound (1-1) of the following formula.

[0049] <Synthesis Example of Compound (1-2)> Compound (1-2) can be obtained by referring to a general benzotriazole synthesis method (for example, the method described in JP-A-2004-509877). That is, 4-methyl-2-(2-nitro-4-chloro-phenylazo)-phenol, N,N-dimethylacetamide, and sodium azide are stirred together, or 4-methyl-6-(2,5-dichlorophenylazo)-phenol, dimethylformamide, sodium azide, triethylamine, and copper(I) bromide are stirred together, and after the reaction is completed, the mixture is extracted with toluene, washed with water, and dried to obtain compound (1-2) of the following formula.

[0050] <Synthesis example of compound (1-3)> Synthesis of UVA326-BPin

[0051] Under an argon atmosphere, a 1 L two-neck flask was charged with UVA326 (24.3 g, 76.9 mmol, 1.00 eq), bis(pinacolato)diboron (25.4 g, 100 mmol, 1.30 eq), potassium acetate (22.6 g, 231 mmol, 3.00 eq), and toluene (485 mL), and the mixture was subjected to 10 cycles of vacuum purging with argon. [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II) dichloromethane adduct (Pd(dppf)Cl2·CHCl2; 6.28 g, 7.69 mmol, 0.10 eq) was added and the mixture was subjected to 10 cycles of vacuum purging with argon. The mixture was then heated to reflux at 120 °C for 2 h. After the reaction, the mixture was cooled to room temperature and filtered through Celite. The filtrate was concentrated to yield 51.1 g of a crude black solid. The crude product was purified using a silica gel column (φ=10 cm column tube, 1.25 kg of silica gel, solvent: chloroform / hexane=1 / 1→chloroform / hexane=7 / 3) to obtain 25.5 g (62.6 mmol, y=81.4%) of a pale orange solid as UVA326-BPin. 1 H NMR (500 MHz, CDCl3) : δ 11.71 (s,1H), 8.44 (s,1H), 8.12-8.10 (m,1H), 7.89 (dd,1H,J=8.5Hz,1.0Hz), 7.84 (dd,1H,J=8.5Hz,1.0Hz), 7.19-7.16 (m,1H), 2.39 (s,3H), 1.49 (s,9H), 1.39 (s,12H).

[0052] Synthesis of UVA326-OH

[0053] Under an argon atmosphere, UVA326-BPin (25.5 g, 62.6 mmol, 1.00 eq) was dissolved in THF (250 mL) in a 1 L recovery flask and cooled on ice. 2.5 M aqueous sodium hydroxide (50 mL, 125 mmol, 2.00 eq) was added, followed by the dropwise addition of 30% aqueous hydrogen peroxide (75.0 mL, 748 mmol, 11.9 eq) over 15 min. The mixture was warmed to room temperature and stirred for 1.5 h, after which the reaction mixture was separated with chloroform (250 mL). The aqueous layer was extracted with chloroform (100 mL). The combined organic layer was dried over sodium sulfate, filtered, and concentrated to approximately one-third of its original volume. Water (200 mL) was added, and the organic layer was evaporated under reduced pressure. Ethyl acetate (200 mL) was added to the remaining aqueous layer, and the organic layer was separated. The organic layer was washed with water (200 mL), dried over sodium sulfate, filtered, and concentrated. A crude product weighing 18.1 g was obtained as a yellow-green amorphous substance. The crude product was purified using a silica gel column (φ=8 cm column tube, 450 g of silica gel, solvent: ethyl acetate / hexane = 1 / 4) to obtain 16.7 g of a light orange solid as a crude product. The crude product was dissolved in chloroform (11 mL of chloroform per 1 g of crude product) and added to hexane (33 mL of hexane per 1 g of crude product) while filtering. After stirring at room temperature for 30 minutes, the precipitated solid was suction filtered and dried under reduced pressure. 12.6 g (42.5 mmol, y=67.8%) of a pale yellow solid was obtained as UVA326-OH (compound (1-3)). 1 H NMR (500 MHz, CDCl3) : δ 11.61 (s,1H), 8.04-8.01 (m,1H), 7.83 (dd,1H,J=9.5Hz,0.5Hz), 7.17-7.14 (m,2H), 7.12 (dd,1H,J=9.0Hz,2.0Hz), 5.12 (s,1H), 2.37 (s,3H), 1.49 (s,9H).

[0054] Example 1 100 g of bisphenol A (BPA: manufactured by Mitsubishi Chemical Corporation) and 0.5 g of hydrosulfite were added and dissolved in 620 ml of a 9 wt % aqueous sodium hydroxide solution. 300 ml of dichloromethane was added to this solution, and while stirring, the solution temperature was set to 20° C., and 60.7 g of phosgene was further blown in over 30 minutes.

[0055] After the phosgene injection was completed, 11.10 g of the compound represented by formula (1-1) dissolved in 200 ml of dichloromethane was added and emulsified by vigorously stirring for 7 minutes, and then 0.5 ml of triethylamine was added as a polymerization catalyst and polymerization was carried out for about 30 minutes.

[0056] The polymerization solution was separated into an aqueous layer and an organic layer, and the organic layer was neutralized with phosphoric acid and repeatedly washed with pure water until the pH of the washings reached 7.0. The organic solvent was evaporated from the purified polycarbonate resin to obtain a polycarbonate resin powder. The polycarbonate resin powder was dried at 120°C for 24 hours to completely evaporate the solvent.

[0057] (Analysis Results) The physical properties of the obtained resin are shown in Table 1. Mv was 23,000, and the wavelength at which the transmittance became 0% was 419 nm.

[0058] Example 2 A polycarbonate resin powder was obtained in the same manner as in Example 1, except that the compound represented by formula (1-1) was replaced with 7.09 g of a compound represented by formula (1-2).

[0059] (Analysis Results) The physical properties of the obtained resin are shown in Table 1. Mv was 17,000, and the wavelength at which the transmittance became 0% was 392 nm.

[0060] Example 3 A polycarbonate resin powder was obtained in the same manner as in Example 1, except that the compound represented by formula (1-1) was replaced with 3.95 g of the compound represented by formula (1-3).

[0061] (Analysis Results) The physical properties of the obtained resin are shown in Table 1. Mv was 46,000, and the wavelength at which the transmittance became 0% was 365 nm.

[0062] Comparative Example 1 A polycarbonate resin powder was obtained in the same manner as in Example 1, except that the compound represented by formula (1-1) was replaced with 6.17 g of a compound represented by the following formula (SEESORB 701, manufactured by Shipro Kasei Co., Ltd.).

[0063] (Analysis Results) The physical properties of the obtained resin are shown in Table 1. Mv was 17,000, and the wavelength at which the transmittance became 0% was 349 nm.

[0064] Comparative Example 2 A bisphenol A polycarbonate resin (trade name: S-3000F, manufactured by Mitsubishi Engineering-Plastics Corporation, Iupilon (registered trademark), having a terminal structure derived from para-t-butylphenol) was used.

[0065] (Analysis Results) The physical properties of the obtained resin are shown in Table 1. Mv was 21,000, and the wavelength at which the transmittance became 0% was 286 nm.

[0066] Comparative Example 3 The compound represented by formula (1-1) was added to the above-mentioned S-3000F, and the S-3000F and the compound represented by formula (1-1) were melt-mixed so that the mass ratio of S-3000F:compound represented by formula (1-1) was 88.9:11.1.

[0067] (Analysis Results) The physical properties of the obtained resin are shown in Table 1. Mv was 21,000, and there was no wavelength at which the transmittance was 0%.

[0068] Other physical properties of the terminally modified polycarbonate resin are also shown in Table 1.

[0069]

[0070] As shown in Table 1, the terminally modified polycarbonate resin of the present invention not only has high transmittance over a wide wavelength range, good adhesion, and high heat resistance, but also has stable thermal decomposition behavior, generates little gas during molding, and can suppress mold deposits. The terminally modified polycarbonate resin of the present invention, which has such properties, is applicable to a variety of applications, including transparent substrates such as optical materials, automotive parts, and coatings, and is particularly suitable for molding materials used outdoors, such as sunglasses lenses.

Claims

1. A terminal-modified polycarbonate resin comprising a terminal structure (A) derived from a hydroxy compound represented by general formula (1) and a structural unit (B) derived from a dihydric phenol compound. (In the above general formula (1), R １ represents an alkyl group having 1 to 6 carbon atoms which may be branched, R ２ represents a halogen, a hydroxyl group, or a phenylthio group which may have a substituent, and n represents an integer of 0 to 4.

2. The terminally modified polycarbonate resin according to claim 1, wherein the hydroxy compound represented by the general formula (1) is a compound represented by any one of the following formulas (1-1), (1-2), or (1-3), or a combination of two or more of these compounds:

3. The terminal-modified polycarbonate resin according to claim 1, wherein the dihydric phenol compound is a compound represented by the following general formula (2): (In the formula, R ５ ~R ８ each independently represents hydrogen, a halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, ２ -, -CO-, or a divalent group represented by any one of the following general formulas (3) to (6): (In general formulas (3) to (6), R ９ and R １０ each independently represents hydrogen, a halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or ９ and R １０ are bonded together to form a carbon ring having 3 to 20 carbon atoms or a heterocycle having 1 to 20 carbon atoms; c represents an integer of 0 to 20; R １１ and R １２ each independently represents hydrogen, a halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or １１ and R １２ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; R １３ ~R １６ each independently represents hydrogen, a halogen, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 5 carbon atoms which may have a substituent, an aryl group having 6 to 12 carbon atoms which may have a substituent, an aralkyl group having 7 to 17 carbon atoms which may have a substituent, or an alkenyl group having 2 to 15 carbon atoms which may have a substituent, or １３ and R １４ and R １５ and R １６ are bonded to each other to form a carbocyclic ring having 3 to 20 carbon atoms or a heterocyclic ring having 1 to 20 carbon atoms; R １７ ~R ２６ each independently represents hydrogen or an alkyl group having 1 to 3 carbon atoms; R １７ ~R ２６ At least one of the groups is an alkyl group having 1 to 3 carbon atoms.

4. The terminally modified polycarbonate resin according to claim 3, wherein X is a divalent group represented by general formula (3).

5. The terminal-modified polycarbonate resin according to claim 3, wherein the dihydric phenol compound is a bisphenol compound.

6. The terminal-modified polycarbonate resin according to claim 5, wherein the bisphenol compound is selected from the group consisting of bisphenol A, bisphenol AP, bisphenol Z, bisphenol CD, bisphenol C, bisphenol IOTD, bisphenol IBTD and bisphenol MIBK.

7. The terminally modified polycarbonate resin according to claim 6, wherein the bisphenol compound is bisphenol A.

8. The terminally modified polycarbonate resin according to claim 7, wherein the hydroxy compound represented by the general formula (1) is a compound represented by any one of the following formulas (1-1), (1-2), or (1-3), or a combination of two or more of these compounds:

9. The terminally modified polycarbonate resin according to claim 1, having a viscosity average molecular weight of 10,000 to 60,000.

10. A terminally modified polycarbonate resin according to claim 1, wherein the terminal structure (A) is contained in an amount of 0.5 mass% or more relative to the structural unit (B) derived from the dihydric phenol compound.

11. The terminally modified polycarbonate resin according to claim 1, characterized in that the transmittance at 330 nm is 1% or less.

12. An optical material comprising the terminally modified polycarbonate resin according to claim 1.

13. An optical material comprising the terminally modified polycarbonate resin according to claim 8.

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