Method for producing a hydrogenated polymer using porous catalyst

Abstract

Provided is a hydrogenation method that can finish in less time, i.e., a hydrogenation method in which a hydrogenation reaction can finish in less time due to an improvement in the reaction rate of the hydrogenation reaction. One aspect of the present invention provides a method for producing a hydrogenated polymer by hydrogenation of an aromatic ring of an aromatic vinyl compound polymer, said method comprising performing a hydrogenation reaction using an aromatic vinyl compound polymer, a solvent, and a hydrogenation catalyst, wherein the hydrogenation catalyst is a porous catalyst, and the total volume of pores having a pore diameter of 50-300 Å in the porous catalyst is 0.17-1.00 mL / g.

Description

Method for producing hydrogenated polymers using porous catalysts

[0001] The present invention relates to a method for producing a hydrogenated polymer using a porous catalyst. In particular, the present invention relates to a method for producing a hydrogenated polymer by hydrogenating the aromatic rings of an aromatic vinyl compound polymer (nuclear hydrogenation).

[0002] In recent years, amorphous plastics such as acrylic resins, methacrylic resins, styrene-based resins, polycarbonate resins, and cyclic polyolefin resins have been used in a variety of applications, and due to their optical characteristics, they are in particularly high demand as optical materials for optical lenses, optical disk substrates, etc. These types of optical materials are required to have not only high transparency but also high performance with an excellent balance of high heat resistance, low water absorption, mechanical properties, etc.

[0003] In order to meet such demands, various improvements have been made to resins, and one example of such improvements is the hydrogenation (nuclear hydrogenation) of aromatic resins.

[0004] Japanese Patent No. 5,145,728 (Patent Document 1) discloses a method for producing a hydrogenated polymer, comprising a step of hydrogenating the aromatic rings in a predetermined aromatic vinyl compound-(meth)acrylate copolymer in a solvent in the presence of a catalyst comprising palladium supported on zirconium oxide. Japanese Patent No. 5,109,533 (Patent Document 2) discloses a method for producing a predetermined hydrogenation catalyst for producing a hydrogenated polymer by hydrogenating the aromatic rings of an aromatic polymer. Japanese Patent Publication No. 2002-521,508 (Patent Document 3) discloses an invention relating to a method for hydrogenating an aromatic polymer in the presence of a catalyst, characterized in that the catalyst uses a metal from Group VIII of the Periodic Table together with an alumina-containing support. Japanese Patent Publication No. 2002-521,509 (Patent Document 4) discloses an invention relating to a method for hydrogenating an aromatic polymer, characterized in that the metal from Group VIII is present together with a support made of silicon dioxide, aluminum oxide, or a mixture thereof. JP-A-2002-536470 (Patent Document 5) discloses an invention relating to a method for hydrogenating aromatic polymers, characterized in that a metal of subgroup VIII is present together with a support made of silicon dioxide, aluminum oxide, or a mixture thereof.

[0005] In Japanese Patent Laid-Open No. 03-076706 (Patent Document 6), when hydrogenating an aromatic ring of a styrene-based resin using a palladium catalyst supported on a carrier, the carrier has a specific surface area of ​​100 to 500 m ２JP 2001-098016 A (Patent Document 7) discloses an invention relating to a method for producing a hydrogenated styrene-based resin by nuclear hydrogenation of a styrene-based resin, characterized by using silica having a crystallite diameter of 200 to 500 Å and a molecular weight of 1000 / g. JP 2001-098016 A (Patent Document 7) discloses an invention relating to a method for producing a hydrogenated alicyclic olefin polymer, in which aromatic rings and / or carbon-carbon unsaturated bonds of a cyclic olefin polymer are hydrogenated in the presence of a hydrogenation catalyst containing at least one metal component selected from the group consisting of nickel, palladium, and platinum, the metal component having a crystallite diameter of 100 Å or less. Japanese Patent Laid-Open No. 2001-098017 (Patent Document 8) discloses an invention relating to a method for producing a hydrogenated alicyclic olefin polymer, in which aromatic rings and / or carbon-carbon unsaturated bonds of a cyclic olefin polymer are hydrogenated in the presence of a hydrogenation catalyst containing at least one metal component A selected from the group consisting of nickel, palladium, and platinum, and at least one metal component B selected from the group consisting of zirconium, titanium, and hafnium. Japanese Patent Laid-Open No. 2003-212923 (Patent Document 9) discloses a heterogeneous hydrogenation catalyst comprising a transition metal of Groups 8 to 10 of the periodic table supported on a carrier, the content of particles with a particle diameter of 1 μm or less being 1% by volume or less, and a specific surface area of ​​50 to 300 m. ２ JP 2006-124430 A (Patent Document 10) discloses a method for producing a hydrogenated alicyclic structure-containing polymer, which comprises the steps of hydrogenating carbon-carbon double bonds in an alicyclic structure-containing polymer selected from the group consisting of norbornene polymers, vinyl cyclic hydrocarbon polymers, and cyclic conjugated diene polymers, using a heterogeneous hydrogenation catalyst having a molecular weight of 1000 to 10000 / g to obtain a hydrogenated alicyclic structure-containing polymer, and then removing the hydrogenation catalyst. JP 2006-124430 A (Patent Document 10) discloses a method for producing a hydrogenated aromatic vinyl polymer by hydrogenating an aromatic vinyl polymer using a hydrogenation catalyst, in which the hydrogenation catalyst (i) has a temperature at which the TCD intensity measured by a temperature-programmed reduction reaction method reaches a maximum value in the range of 90 to 140°C, and (ii) has a metal surface area of ​​18 m2 or less as measured under predetermined conditions by the BET method using hydrogen. ２ The present invention discloses a method for producing a hydrogenated aromatic vinyl polymer characterized by having a molecular weight of 1 / g or more.

[0006] Japanese Patent No. 5145728 Japanese Patent No. 5109533 Special Publication No. 2002-521508 Special Publication No. 2002-521509 Special Publication No. 2002-536470 Japanese Patent Application Laid-Open No. 03-076706 Japanese Patent Application Laid-Open No. 2001-098016 Japanese Patent Application Laid-Open No. 2001-098017 Japanese Patent Application Laid-Open No. 2003-212923 Japanese Patent Application Laid-Open No. 2006-124430

[0007] Optical lenses used in VR / AR lenses, smartphone cameras, etc., require high transparency as well as thermal stability, low water absorption, dimensional stability, etc. In this regard, if the hydrogenation reaction is allowed to proceed for a long period of time, there is a risk that this could have a negative impact on the resin (such as a decrease in molecular weight). In light of this situation, there is currently a demand for a hydrogenation method that can be completed in a shorter time, that is, a hydrogenation method that can complete the hydrogenation reaction in a shorter time by improving the reaction rate of the hydrogenation reaction.

[0008] As a result of extensive research, the inventors discovered that the reaction rate can be improved and the hydrogenation reaction can be completed in a shorter time by using a porous catalyst having a large pore volume for pores with pore diameters within a predetermined range, and thus arrived at the present invention.

[0009] That is, the present invention provides the following production methods, etc.: [1] A production method for a hydrogenated polymer by hydrogenating the aromatic rings of an aromatic vinyl compound-based polymer, comprising carrying out a hydrogenation reaction using the aromatic vinyl compound-based polymer, a solvent, and a hydrogenation catalyst, the hydrogenation catalyst being a porous catalyst, and the total volume of pores having a pore diameter of 50 to 300 Å of the porous catalyst being 0.17 to 1.00 mL / g. [2] A production method for a hydrogenated polymer by hydrogenating the aromatic vinyl compound-based polymer, the method comprising carrying out a hydrogenation reaction using the aromatic vinyl compound-based polymer, a solvent, and a hydrogenation catalyst, the hydrogenation catalyst being a porous catalyst, the total volume of pores having a pore diameter of 50 to 300 Å of the porous catalyst being 0.17 to 1.00 mL / g. [3] A production method for a hydrogenated polymer by hydrogenating the aromatic vinyl compound-based polymer, the method comprising carrying out a hydrogenation reaction using the aromatic vinyl compound-based polymer, a solvent, and a hydrogenation catalyst ... ２ / g. [3] The manufacturing method according to [1] or [2], wherein the ratio of the total volume of pores having a pore diameter of less than 30 Å to the total pore volume of the porous catalyst is less than 2.0%. [4] The manufacturing method according to any one of [1] to [3], wherein the porous catalyst comprises a porous support and a metal element. [5] The manufacturing method according to [4], wherein the porous support comprises one or more selected from the group consisting of zirconia, silica, alumina, silica-alumina, activated carbon, and diatomaceous earth. [6] The manufacturing method according to [4] or [5], wherein the metal element is one or more metals or compounds thereof selected from the group consisting of palladium, platinum, ruthenium, rhodium, and nickel. [7] The manufacturing method according to any one of [1] to [6], wherein the aromatic vinyl compound-based polymer comprises one or more selected from the group consisting of a styrene-butadiene copolymer, a styrene-isoprene copolymer, a styrene-methyl methacrylate copolymer, a styrene-maleic anhydride copolymer, a styrene-vinyl acetate copolymer, and polystyrene. [8] The aromatic vinyl compound-based polymer has at least one structure selected from the group consisting of the following (1) to (4): (wherein l and m represent the molar ratio of each structural unit, l is 10 to 100, and m is 90 to 0) (wherein l and m represent the molar ratio of each structural unit, l is 50 to 90, and m is 50 to 10) (wherein l and m represent the molar ratio of each structural unit, l is 80 to 99, and m is 20 to 1) (wherein l and m represent the molar ratios of the respective structural units, l is 80 to 99, and m is 20 to 1). [9] The method for producing an aromatic vinyl compound-based polymer according to any one of [1] to [7], wherein the weight average molecular weight of the aromatic vinyl compound-based polymer is 5×10 ４ ~30 x 10 ４

[10] The method according to any one of [1] to [9], wherein the solvent comprises one or more selected from the group consisting of methyl acetate, ethyl acetate, butyl acetate, methyl isobutyrate, methyl propionate, propylene glycol monomethyl ether acetate, tetrahydrofuran, dioxane, cyclohexane, C7 to C15 monoalkylcyclohexane, C8 to C15 dialkylcyclohexane, C9 to C15 trialkylcyclohexane, C10 to C15 tetraalkylcyclohexane, cyclooctane, C9 to C15 monoalkylcyclooctane, C10 to C15 dialkylcyclooctane, C11 to C15 trialkylcyclooctane, C12 to C15 tetraalkylcyclooctane, n-octane, and n-decane.

[11] The method according to any one of [1] to

[10] , wherein the hydrogenation rate is 90 to 100%.

[12] The production method according to any one of [1] to

[11] , wherein the hydrogenation reaction is carried out under conditions of 100 to 200°C for 1 to 50 hours.

[13] The production method according to any one of [1] to

[12] , wherein the amount of the hydrogenation catalyst added is 0.01 to 0.3 times the weight of the aromatic vinyl compound-based polymer.

[14] The production method according to any one of [1] to

[13] , wherein the total volume of pores having a pore diameter of 50 to 300 Å in the porous catalyst is 0.17 to 0.50 mL / g.

[0010] According to one aspect of the present invention, the rate of the hydrogenation reaction is improved, thereby enabling the hydrogenation reaction to be completed in a shorter time. According to a preferred aspect of the present invention, the hydrogenation reaction can be completed in a shorter time, which is expected to reduce damage to the polymer, such as a decrease in molecular weight.

[0011] The present invention will be described in detail below. The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention to these embodiments. The present invention can be implemented in various forms without departing from the spirit of the present invention. Furthermore, any paragraph headings used in this specification are for organizational purposes only and should not be construed as limiting the subject matter described.

[0012] [Method for Producing Hydrogenated Polymer] One aspect of the present invention provides a method for producing a hydrogenated polymer by hydrogenating aromatic rings of an aromatic vinyl compound-based polymer, the method comprising carrying out a hydrogenation reaction using the aromatic vinyl compound-based polymer, a solvent, and a hydrogenation catalyst, wherein the hydrogenation catalyst is a porous catalyst, and the total volume of pores having pore diameters of 50 to 300 Å in the porous catalyst is 0.17 to 1.00 mL / g.

[0013] According to one aspect of the present invention, there is provided a method for producing a hydrogenated polymer by hydrogenating aromatic rings of an aromatic vinyl compound-based polymer, the method comprising: carrying out a hydrogenation reaction using the aromatic vinyl compound-based polymer, a solvent, and a hydrogenation catalyst; the hydrogenation catalyst is a porous catalyst; and the total volume of pores in the porous catalyst, having pore diameters of 50 to 300 Å, is 0.17 to 0.50 mL / g.

[0014] Specific embodiments of the present invention will be described below.

[0015] <Aromatic Vinyl Compound-Based Polymer> A production method according to one embodiment of the present invention relates to a method for producing a hydrogenated polymer by hydrogenating the aromatic ring of an aromatic vinyl compound-based polymer. In this specification, "aromatic vinyl compound-based polymer" refers to a polymer containing units derived from aromatic vinyl compounds as structural units. Therefore, the aromatic vinyl compound-based polymer may be a polymer (homopolymer) composed of units derived from one type of aromatic vinyl compound, or a copolymer containing units derived from two or more types of aromatic vinyl compounds as structural units, or a copolymer containing units derived from one or more aromatic vinyl compounds and units derived from one or more compounds other than aromatic vinyl compounds as structural units. For example, the aromatic vinyl compound-based polymer used in the production method according to one embodiment of the present invention may be a binary copolymer containing units derived from one type of aromatic vinyl compound and units derived from one type of compound other than aromatic vinyl compounds as structural units, or a ternary copolymer containing units derived from one type of aromatic vinyl compound and units derived from two compounds other than aromatic vinyl compounds as structural units. In this specification, "aromatic vinyl compound-based unit" refers to a unit having a structure in which the C═C double bond of the vinyl group in the aromatic vinyl compound is opened by polymerization.

[0016] (Monomer) The aromatic vinyl compound-based polymer used in the production method according to one embodiment of the present invention is not particularly limited, and examples of aromatic vinyl compound monomers include polymers using styrene; alkylstyrenes such as α-methylstyrene, α-ethylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 1,3-dimethylstyrene, and p-tert-butylstyrene (the number of carbon atoms in the alkyl group moiety is preferably 1 to 5); p-hydroxystyrene; alkoxystyrenes such as p-methoxystyrene, m-butoxystyrene, and p-butoxystyrene (the number of carbon atoms in the alkoxy group moiety is preferably 1 to 5); halogenated styrenes such as o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, 2,4-dichlorostyrene, and 2,6-dichlorostyrene; vinylnaphthalene, vinylanthracene, and the like. These monomers may be used alone or in combination. In a preferred embodiment of the present invention, styrene is used as the aromatic vinyl compound monomer.

[0017] The aromatic vinyl compound-based polymer used in the production method according to some embodiments of the present invention is a polymer using, in addition to an aromatic vinyl compound monomer, a monomer of a compound other than an aromatic vinyl compound, such as (meth)acrylate, diene, or unsaturated dicarboxylic acid derivative. Examples of (meth)acrylates include (meth)acrylic acid alkyl esters such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, dodecyl (meth)acrylate, and octadecyl (meth)acrylate (the number of carbon atoms in the alkyl group is preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 5); (meth)acrylic acid cycloalkyl esters or cyclic saturated hydrocarbon esters such as cyclohexyl (meth)acrylate and isobornyl (meth)acrylate (the number of ring carbon atoms in each case is preferably 5 to 20, more preferably 5 to 10); (meth)acrylic acid hydroxyalkyl esters such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 2-hydroxy-2-methylpropyl (meth)acrylate (the number of carbon atoms in the alkyl group is preferably 1 to 20, more preferably 1 to 5); more preferably 1 to 10, and even more preferably 1 to 5); (meth)acrylic acid alkoxyalkyl esters such as (2-methoxyethyl) (meth)acrylate and (2-ethoxyethyl) (meth)acrylate (the number of carbon atoms in the alkyl group moiety is preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 5. The number of carbon atoms in the alkoxy group moiety is preferably 1 to 10, more preferably 1 to 5, and even more preferably 1 or 2); (meth)acrylic acid phenyl esters such as phenyl (meth)acrylate; (meth)acrylic acid arylalkyl esters such as benzyl (meth)acrylate (the number of carbon atoms in the aryl group moiety is preferably 6 to 10. The number of carbon atoms in the alkyl group moiety is preferably 1 to 5); and (meth)acrylic acid esters having a phospholipid structure such as 2-(meth)acroyloxyethyl phosphorylcholine. One (meth)acrylate may be used alone, or two or more may be used in combination.As the (meth)acrylate, methyl (meth)acrylate is preferred.

[0018] Examples of dienes include 1,2-butadiene, 1,3-butadiene, 1,2-pentadiene, 1,3-pentadiene, 1,4-pentadiene, 1,2-hexadiene, 1,3-hexadiene, 1,4-hexadiene, 1,5-hexadiene, 1,3-heptadiene, 1,3-octadiene, 1,3-nonadiene, 1,3-decadiene, isoprene, cyclopentadiene, 1,3-cyclohexadiene, and 1,4-cyclohexadiene. One diene may be used alone, or two or more dienes may be used in combination. Conjugated dienes, such as 1,3-butadiene or isoprene, are preferred.

[0019] Examples of the unsaturated dicarboxylic acid derivative include maleic anhydride, maleic acid, itaconic anhydride, itaconic acid, citraconic anhydride, citraconic acid, and aconitic acid, and among these, maleic anhydride is preferred.

[0020] The aromatic vinyl compound-based polymer used in the production method according to one embodiment of the present invention may contain other monomer components than those described above, as long as the effects of the present invention are not impaired. For example, the other monomer components may be contained in an amount of 0 to 10% or 0 to 5% by molar ratio relative to the total monomer components.

[0021] In a preferred embodiment of the present invention, the aromatic vinyl compound-based polymer comprises one or more selected from the group consisting of a styrene-butadiene copolymer, a styrene-isoprene copolymer, a styrene-methyl methacrylate copolymer, a styrene-maleic anhydride copolymer, a styrene-vinyl acetate copolymer, and polystyrene. The styrene-butadiene copolymer may be a copolymer of styrene and 1,2-butadiene, 1,3-butadiene, or a combination thereof. These polymers may be polymerized from the respective monomers as described below, or commercially available products may be used. For example, the polystyrene may be "GPPS HF-77" manufactured by PS Japan.

[0022] In a preferred embodiment of the present invention, the aromatic vinyl compound-based polymer has at least one structure selected from the group consisting of the following (1) to (4): (wherein l and m represent the molar ratio of each constituent unit, l is 10 to 100, preferably 15 to 80, more preferably 18 to 50, and even more preferably 20 to 40, and m is 90 to 0, preferably 85 to 20, more preferably 82 to 50, and even more preferably 80 to 60; or l is 100 and m is 0 (i.e., polystyrene).) (wherein l and m represent the molar ratio of each constituent unit, l is 50 to 90, preferably 60 to 80, more preferably 65 to 75, and m is 50 to 10, preferably 40 to 20, more preferably 35 to 25) (wherein l and m represent the molar ratio of each structural unit, l is 80 to 99, preferably 85 to 99, more preferably 89 to 99, and m is 20 to 1, preferably 15 to 1, more preferably 11 to 1). (wherein l and m represent the molar ratio of each constituent unit, l is 80 to 99, preferably 85 to 99, more preferably 88 to 98, and m is 20 to 1, preferably 15 to 1, more preferably 12 to 2).

[0023] The aromatic vinyl compound-based polymer having the structure of formula (2) contains, in part, the following structural units: (wherein n represents an arbitrary integer, R １ , R ２ and R ３ are each independently a hydrogen atom or a methyl group.) This structural unit is a cyclized structural unit derived from butadiene of formula (2). Alternatively, instead of or in addition to such a structural unit, the aromatic vinyl compound-based polymer having the structure of formula (2) may partially contain the following structural unit: (wherein n represents any integer.) This structural unit is formed by polymerizing the butadiene-derived structural unit of formula (2) at the 1- and 2-positions of butadiene.

[0024] (Method for Producing Aromatic Vinyl Compound-Based Polymers) Aromatic vinyl compound-based polymers can be produced by polymerizing various monomers. There are no particular limitations on the method for polymerizing one or more aromatic vinyl compounds or the method for copolymerizing an aromatic vinyl compound with a monomer other than an aromatic vinyl compound monomer, and known methods such as radical polymerization, ionic polymerization, and coordination polymerization can be used. From an industrial perspective, radical polymerization is simple and preferable. Known radical polymerization methods can be appropriately selected from bulk polymerization, solution polymerization, emulsion polymerization, suspension polymerization, and other known methods. Examples of bulk polymerization and solution polymerization include a continuous polymerization method in which a monomer composition obtained by mixing monomer components, a chain transfer agent, and a polymerization initiator (and, in the case of solution polymerization, a solvent) is continuously supplied to a complete mixing tank and polymerized at 100 to 180°C. Examples of the solvent used in the solution polymerization method include hydrocarbon solvents such as toluene, xylene, cyclohexane, and methylcyclohexane; ester solvents such as ethyl acetate; ketone solvents such as acetone and methyl ethyl ketone; ether solvents such as tetrahydrofuran and 1,4-dioxane; and alcohol solvents such as methanol and isopropanol.

[0025] In the constituent units of the aromatic vinyl compound-based polymer, the molar ratio (A / B) of the constituent units (A moles) of a monomer other than an aromatic vinyl compound monomer to the constituent units (B moles) derived from an aromatic vinyl compound is preferably 0 to 4, more preferably 0 to 3, and even more preferably 0 to 2.

[0026] The weight average molecular weight of the aromatic vinyl compound polymer used in some embodiments of the present invention is 1×10 ４ ~100 x 10 ４ is preferred, and 5 × 10 ４ ~50 x 10 ４ is more preferable, and 5×10 ４ ~30 x 10 ４ is more preferable. ４ Less than or 100 x 10 ４Although polymers exceeding this weight-average molecular weight can also be hydrogenated by the method according to some embodiments of the present invention, copolymers having a weight-average molecular weight within the above range are preferred because they have sufficient mechanical strength, are practically usable, and have a suitable viscosity, making them easy to handle. In this specification, the weight-average molecular weight is a value determined by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent, converted into polystyrene.

[0027] <Hydrogenation> In this specification, "hydrogenation of an aromatic vinyl compound-based polymer" means a reaction of adding hydrogen to an aromatic ring of an aromatic vinyl compound-based polymer, for example, reducing a benzene ring to cyclohexane. Such hydrogenation is also called nuclear hydrogenation or nuclear hydrogenation. The hydrogenation of an aromatic vinyl compound-based polymer according to the present invention is carried out using a solvent and a hydrogenation catalyst.

[0028] (Solvent) The aromatic vinyl compound-based polymer used in one embodiment of the present invention is dissolved in a suitable solvent and hydrogenated. When selecting a solvent, it is preferable that the solvent has good solubility for the polymer before and after hydrogenation (i.e., both the aromatic polymer and the hydrogenated polymer) and does not have a site to be hydrogenated. Furthermore, a solvent that allows the reaction to proceed quickly is more preferable. This is because an improved hydrogenation rate shortens the reaction time and reduces damage to the polymer, such as a decrease in molecular weight. Furthermore, when considering the need to devolatilize the solvent components after hydrogenation, it is preferable that the solvent have a high ignition point.

[0029] In one embodiment of the present invention, the solvent comprises one or more selected from the group consisting of methyl acetate, ethyl acetate, butyl acetate, methyl isobutyrate, methyl propionate, propylene glycol monomethyl ether acetate, tetrahydrofuran, dioxane, cyclohexane, C7-C15 monoalkylcyclohexane, C8-C15 dialkylcyclohexane, C9-C15 trialkylcyclohexane, C10-C15 tetraalkylcyclohexane, cyclooctane, C9-C15 monoalkylcyclooctane, C10-C15 dialkylcyclooctane, C11-C15 trialkylcyclooctane, C12-C15 tetraalkylcyclooctane, n-octane, and n-decane. In a preferred embodiment of the present invention, the solvent comprises one or more selected from the group consisting of methyl isobutyrate, methyl propionate, and cyclohexane.

[0030] (Hydrogenation Catalyst) The catalyst used in the hydrogenation of an aromatic vinyl compound-based polymer according to the present invention is a porous catalyst, and the total volume of pores having a pore diameter of 50 to 300 Å of the porous catalyst is 0.17 to 1.00 mL / g. The catalyst used in the hydrogenation of an aromatic vinyl compound-based polymer according to one embodiment of the present invention is a porous catalyst, and the total volume of pores having a pore diameter of 50 to 300 Å of the porous catalyst is 0.17 to 0.50 mL / g. Without wishing to be bound by theory, it is presumed that the relatively high total volume of pores having a pore diameter of 50 to 300 Å among the pores of the porous catalyst allows the aromatic vinyl compound-based polymer to be efficiently incorporated into the pores of the catalyst, thereby increasing the hydrogenation efficiency of the polymer and improving the hydrogenation reaction rate.

[0031] In a preferred embodiment of the present invention, the total volume of pores having a pore diameter of 50 to 300 Å in the porous catalyst may be 0.17 to 0.90 mL / g, 0.17 to 0.80 mL / g, 0.17 to 0.70 mL / g, 0.17 to 0.60 mL / g, 0.18 to 0.50 mL / g, 0.18 to 0.40 mL / g, 0.20 to 0.30 mL / g, or 0.21 to 0.27 mL / g, more preferably 0.17 to 0.80 mL / g or 0.18 to 0.70 mL / g, and even more preferably 0.20 to 0.60 mL / g. Having the total volume of pores having a pore diameter of 50 to 300 Å in the porous catalyst within this range is preferred because the hydrogenation reaction rate of the polymer is improved, thereby enabling the hydrogenation reaction to be completed in a shorter time. Furthermore, it is expected that pores having a pore diameter within this range will be able to suppress a decrease in the BET specific surface area even when the pore volume increases, and will also be able to ensure a reaction field.

[0032] In one embodiment of the present invention, the total volume of pores in the porous catalyst having a pore diameter of 50 Å or more and less than 100 Å may be 0.01 to 0.30 mL / g, 0.03 to 0.25 mL / g, or 0.05 to 0.20 mL / g.

[0033] In one embodiment of the present invention, the total volume of pores having a pore diameter greater than 300 Å of the porous catalyst may be 0.000 to 0.500 mL / g, 0.002 to 0.300 mL / g, or 0.005 to 0.080 mL / g.

[0034] In one embodiment of the present invention, the total volume of pores with a pore diameter of less than 30 Å of the porous catalyst may be 0.00 to 0.10 mL / g, 0.00 to 0.08 mL / g, or 0.00 to 0.05 mL / g.

[0035] The pore size (pore diameter) of the porous catalyst can be measured by gas adsorption or mercury intrusion porosimetry. For example, it can be measured using a nitrogen adsorption apparatus as described in the Examples. The pore volume of the porous catalyst for each pore size can be determined by analyzing the nitrogen adsorption isotherm obtained by the nitrogen adsorption method using the BJH method.

[0036] In a preferred embodiment of the present invention, the ratio of the total volume of pores having a pore diameter of less than 30 Å to the total pore volume of the porous catalyst is less than 2.0%. In another embodiment of the present invention, the ratio of the total volume of pores having a pore diameter of less than 30 Å to the total pore volume of the porous catalyst may be less than 1.5%, or less than 1.0%. Without wishing to be bound by theory, it is presumed that pores that are too small do not contribute to the hydrogenation of the aromatic vinyl compound polymer, and therefore the lower the proportion of pore diameters less than 30 Å, the more efficiently the hydrogenation reaction can proceed. In this specification, the total pore volume means the cumulative pore volume obtained by analyzing, by the BJH method, a nitrogen adsorption isotherm in the range where the relative pressure (P / saturated vapor pressure) obtained by the nitrogen adsorption method is in the range of 0.2 to 1.

[0037] In one embodiment of the present invention, the ratio of the total volume of pores having a pore diameter greater than 300 Å to the total pore volume of the porous catalyst is 1 to 50%. In other embodiments of the present invention, the ratio of the total volume of pores having a pore diameter greater than 300 Å to the total pore volume of the porous catalyst may be 1.5 to 45%, 2 to 40%, or 3 to 30%.

[0038] In one embodiment of the present invention, the ratio of the total volume of pores having a pore diameter of 50 to 300 Å to the total pore volume of the porous catalyst may be 60 to 100%, 70 to 100%, 80 to 100%, 90 to 100%, or 92 to 98%.

[0039] In one embodiment of the present invention, the ratio of the total volume of pores having a pore diameter of 50 Å or more and less than 100 Å to the total pore volume of the porous catalyst may be 3 to 50%, 10 to 95%, 20 to 90%, 25 to 80%, or 25 to 50%.

[0040] In one embodiment of the present invention, the total pore volume of the porous catalyst is from 0.10 to 0.90 mL / g. In other embodiments of the present invention, the total pore volume of the porous catalyst may be from 0.15 to 0.50 mL / g, or from 0.20 to 0.30 mL / g.

[0041] The surface area of ​​the catalyst used in the hydrogenation of the aromatic vinyl compound polymer according to the present invention is not particularly limited, but preferably the BET specific surface area of ​​the porous catalyst is 20 to 150 m２ / g. More preferably, it is 40 to 120 m ２ / g or 50 to 110 m ２ The BET specific surface area of ​​the porous catalyst can be measured by a BET multipoint method using a nitrogen adsorption apparatus.

[0042] In a preferred embodiment of the present invention, the amount of the hydrogenation catalyst added is 0.01 to 0.3 times, more preferably 0.02 to 0.25 times, and even more preferably 0.04 to 0.2 times, by weight, the amount of the aromatic vinyl compound-based polymer. Setting the amount of catalyst within this range is preferred in that it is possible to reduce production costs and it makes it easy to separate the reaction liquid and the catalyst in a post-reaction step.

[0043] In one embodiment of the present invention, the porous catalyst comprises a porous support and a metal element. As the porous support, various porous materials suitable as catalyst supports can be used, but preferably the porous support comprises one or more selected from the group consisting of zirconia (zirconium dioxide), silica, alumina, silica-alumina, activated carbon, and diatomaceous earth.

[0044] There are no particular restrictions on the purity of the material that constitutes the porous carrier, and commercially available materials with purity levels ranging from general-purpose to high-purity products can be used as appropriate.

[0045] The shape, particle size, and other physical properties of the porous carrier used in the catalyst for the method of one embodiment of the present invention, and the method for supporting the metal elements, are not particularly limited as long as the total volume of pores having a pore diameter of 50 to 300 Å is within a predetermined range. The shape, carrier properties, and supporting method suitable for the reaction system and conditions can be appropriately selected and used.

[0046] There are no particular limitations on the method for producing the material constituting the porous support. For example, a commonly known method for producing zirconia is to decompose an aqueous solution of a soluble zirconium salt with a basic substance to form zirconium hydroxide or zirconium carbonate, followed by thermal decomposition. The raw material for the zirconium compound is not limited, and examples include zirconium oxychloride, zirconium oxynitrate, zirconium chloride, zirconium sulfate, zirconium tetraalkoxide, zirconium acetate, and zirconium acetylacetonate. These may be used alone or in combination of two or more. Examples of basic substances used for decomposition include ammonia, alkylamines, ammonium carbonate, ammonium bicarbonate, sodium hydroxide, sodium carbonate, sodium bicarbonate, potassium hydroxide, potassium carbonate, potassium bicarbonate, magnesium hydroxide, calcium hydroxide, lanthanum hydroxide, yttrium hydroxide, and cerium hydroxide. These may be used alone or in combination of two or more.

[0047] In one embodiment of the present invention, the metal element used acts as an active component of the hydrogenation catalyst and includes a metal element having catalytic hydrogenation ability (hereinafter also referred to as a "specific metal component"). Examples of specific metal components include nickel, cobalt, iron, ruthenium, rhodium, palladium, platinum, iridium, copper, silver, molybdenum, tungsten, chromium, and rhenium. The specific metal component may be in either a metallic or cationic state as long as it exhibits hydrogenation ability. Among these, the metallic state is generally preferred because it has stronger hydrogenation ability and is more stable under a reducing atmosphere. The specific metal component may be used alone or in combination of two or more types contained in a solid catalyst. When two or more specific metal components are used, there are no particular restrictions on the combination, mixing ratio, or form, and the metals may be used in the form of a mixture of the individual metals, an alloy, or an intermetallic compound. In a preferred embodiment of the present invention, the metal element is one or more metals or compounds thereof selected from the group consisting of palladium, platinum, ruthenium, rhodium, and nickel, with palladium being particularly preferred.

[0048] The compounds of these metal elements are not particularly limited, and those that are used as raw materials when preparing catalysts by conventionally known methods can be used. Examples of such raw materials include hydroxides, oxides, fluorides, chlorides, bromides, iodides, sulfates, nitrates, acetates, ammine complexes, and carbonyl complexes of the respective metal elements. These can be used alone or in combination of two or more.

[0049] When the specific metal component is palladium, considering that palladium is a noble metal, it is economically desirable to use a small amount of palladium and to utilize palladium effectively. Therefore, it is preferable to use palladium dispersed and supported on a catalyst carrier.

[0050] Palladium compounds that are suitable as raw materials for palladium are those that are soluble in water or organic solvents. Examples of such palladium compounds include palladium chloride, tetrachloropalladium salts, tetraamminepalladium salts, palladium nitrate, and palladium acetate. Among these, palladium chloride is preferred because it has high solubility in water or organic solvents and is easily available industrially. Palladium chloride can be used by dissolving it in an aqueous sodium chloride solution, dilute hydrochloric acid, aqueous ammonia, or the like.

[0051] Palladium or a palladium compound is immobilized on a catalyst support by adding a solution of a palladium compound to the catalyst support or by immersing the catalyst support in a solution of the palladium compound. Typical immobilization methods include adsorption onto the support, crystallization by solvent distillation, and deposition using a reducing substance and / or a basic substance that reacts with the palladium compound. A suitable method can be used. The palladium content in the hydrogenation catalyst prepared by such a method is preferably 0.01 to 20% by mass, more preferably 0.1 to 10% by mass, and even more preferably 0.5 to 5% by mass, calculated as metallic palladium, relative to the total amount of the hydrogenation catalyst. A palladium content of 0.01% by mass or more achieves a more sufficient hydrogenation rate and further increases the conversion rate of the aromatic vinyl compound-based polymer. On the other hand, a palladium content of 20% by mass or less further increases the dispersion efficiency of palladium in the hydrogenation catalyst, allowing for more effective use of palladium.

[0052] Depending on the palladium compound and catalyst preparation method, palladium may be supported on the carrier in a cationic state rather than a metallic state. In such cases, the supported cationic palladium (e.g., present in the form of a palladium compound) can be reduced to metallic palladium before use. Conventional reduction methods and reducing agents can be used without particular limitation. Examples of reducing agents include reducing inorganic gases such as hydrogen gas, carbon monoxide gas, ammonia, and hydrazine; lower oxygen-containing compounds such as methanol, formaldehyde, and formic acid; hydrocarbon compounds such as ethylene, propylene, benzene, and toluene; and hydrides such as sodium borohydride and lithium aluminum hydride. Cationic palladium can be easily reduced to metallic palladium by contacting it with a reducing agent in the gas phase or liquid phase. The reduction conditions can be set appropriately depending on the type and amount of the reducing agent. This reduction operation can be performed using a separate catalyst reduction apparatus before the hydrogenation reduction in the production method according to one embodiment of the present invention, or it can be performed in the reactor used in the production method of this embodiment before the start of the reaction or simultaneously with the reaction operation.

[0053] The hydrogenation catalyst used in one embodiment of the present invention can use a specific metal component as the metal component either alone or in combination with a metal that does not have catalytic hydrogenation ability. Examples include catalysts such as palladium black and platinum black, which are composed of fine metal powders of the specific metal component, and sponge catalysts, which are prepared by forming an alloy from the specific metal component, aluminum, and a small amount of additive, and then leaching all or part of the aluminum.

[0054] In order to further improve the activity, selectivity, physical properties, etc. of the catalyst, compounds of one or more elements selected from the group consisting of lithium, sodium, potassium, rubidium, and cesium as alkali metal elements, magnesium, calcium, strontium, and barium as alkaline earth metal elements, fluorine, chlorine, bromine, and iodine as halogen elements, and mercury, lead, bismuth, tin, tellurium, and antimony as auxiliary additive elements (hereinafter abbreviated as specific additive components) can also be added to the catalyst together with the above-mentioned specific metal components.

[0055] There are no particular limitations on the raw materials for these specific additive components, and those used as raw materials when preparing catalysts by conventionally known methods can be used. Examples of such raw materials include hydroxides, oxides, fluorides, chlorides, bromides, iodides, sulfates, nitrates, acetates, and ammine complexes of the respective metal elements. These may be used alone or in combination of two or more. There are also no particular limitations on the method for adding the specific additive components or the ratio of the specific additive components to the specific metal components.

[0056] As the hydrogenation catalyst used in some embodiments of the present invention, a specific metal component may be used alone, or a specific metal component and a specific non-metal component may be used in combination, and in some cases, a specific additive component may be contained in addition to these.

[0057] In some embodiments of the present invention, the hydrogenation catalyst may be used in combination with a specific metal component and a non-metallic substance. Examples of non-metallic substances include, for example, simple elements, carbides, nitrides, oxides, hydroxides, sulfates, carbonates, and phosphates (hereinafter referred to as "specific non-metallic components"). Specific examples include graphite, diamond, activated carbon, silicon carbide, silicon nitride, aluminum nitride, boron nitride, boron oxide, aluminum oxide (alumina), silicon oxide (silica), titanium oxide, zirconium oxide, hafnium oxide, lanthanum oxide, cerium oxide, yttrium oxide, niobium oxide, magnesium silicate, calcium silicate, magnesium aluminate, calcium aluminate, zinc oxide, chromium oxide, aluminosilicate, aluminosilicophosphate, aluminophosphate, borophosphate, magnesium phosphate, calcium phosphate, strontium phosphate, hydroxyapatite (calcium hydroxyphosphate), chlorapatite, fluorapatite, calcium sulfate, barium sulfate, and barium carbonate. The specific nonmetallic components may be used singly or in combination of two or more. When two or more types are used in combination, the combination, mixing ratio, and form are not particularly limited, and the components may be used in the form of a mixture of individual compounds, a composite compound, or a double salt.

[0058] Depending on the composition of the hydrogenation catalyst or the catalyst preparation method, the specific metal component may be prepared in a cationic state and then reduced to a metallic state. Conventional reduction methods and reducing agents can be used for this purpose and are not particularly limited. Examples of reducing agents include reducing inorganic gases such as hydrogen gas, carbon monoxide gas, ammonia, hydrazine, phosphine, and silane; lower oxygen-containing compounds such as methanol, formaldehyde, and formic acid; and hydrides such as sodium borohydride and lithium aluminum hydride. The specific metal component in a cationic state is reduced in the gas phase or liquid phase in the presence of these reducing agents to convert it to a metallic state. The reduction conditions can be set appropriately depending on the type and amount of the specific metal component and reducing agent. This reduction operation may be performed using a separate catalytic reduction device before the hydrogenation reduction in the production method according to some embodiments of the present invention, or it may be performed in the reactor used in the production method according to some embodiments of the present invention before the start of the reaction or simultaneously with the reaction operation.

[0059] In addition, there are no particular limitations on the metal content and shape of the hydrogenation catalyst used in some embodiments of the present invention. The shape may be powder or molded, and the shape and molding method when molded are also no particular limitations. For example, spherical products, tablet-molded products, extrusion-molded products, and shapes obtained by crushing these to an appropriate size can be appropriately selected and used.

[0060] (Other Reaction Conditions) In one embodiment of the present invention, the concentration of the copolymer (aromatic polymer + hydrogenated polymer) in the solution during the hydrogenation reaction is usually 1 to 50% by weight, preferably 3 to 30% by weight, and more preferably 5 to 25% by weight. By setting the upper limit of the copolymer concentration to a predetermined value or less, it is possible to avoid inconvenience in handling due to a decrease in the reaction rate and an increase in the solution viscosity. Alternatively, it is preferable from the standpoint of productivity and / or economy to set the lower limit of the concentration to a predetermined value or more.

[0061] The hydrogenation (hydrogenation) reaction in the production method according to one embodiment of the present invention is carried out using a raw material solution in which an aromatic vinyl compound-based polymer is dissolved in a solvent. The reaction may be carried out in either a suspension bed or a fixed bed, and known techniques such as batch reactions and continuous flow reactions can be used. When the reaction is carried out in a suspension bed, the carrier particle size is usually in the range of 0.1 to 1,000 μm, preferably 1 to 500 μm, and more preferably 5 to 200 μm. By setting the particle size to a predetermined size or greater, catalyst separation after the hydrogenation reaction becomes easy, and by setting the upper limit of the particle size to a predetermined value or less, a decrease in the reaction rate can be prevented.

[0062] In one embodiment of the present invention, the hydrogenation reaction is carried out under conditions of 100 to 200°C and 1 to 50 hours. Preferred reaction conditions are a temperature of 100 to 200°C, a hydrogen pressure of 3 to 30 MPa, and a reaction time of 3 to 30 hours. By setting the reaction temperature at a predetermined temperature or higher, the reaction rate increases, and by setting the upper limit of the reaction temperature at a predetermined temperature or lower, side reactions such as polymer decomposition and solvent hydrogenolysis can be suppressed. Furthermore, while the reaction rate can be increased by setting the hydrogen pressure at a predetermined value or higher, from an economical viewpoint, an upper limit of about 30 MPa is preferred.

[0063] A hydrogenated polymer can be obtained by separating the hydrogenation catalyst and volatile components (solvent, etc.) from the polymer solution after the hydrogenation reaction. The catalyst can be separated by known techniques such as filtration or centrifugation. Considering coloration and the effect on mechanical properties, it is desirable to keep the residual catalyst concentration in the polymer as low as possible. For example, when a catalyst in which palladium metal is supported on a porous zirconia carrier is used as the porous catalyst, the Pd concentration is preferably 30 ppb or less, more preferably 20 ppb or less, and even more preferably 10 ppb or less, and the Zr concentration is preferably 1000 ppb or less, more preferably 800 ppb or less, and even more preferably 600 ppb or less.

[0064] After separating the catalyst, volatile components such as the solvent can be separated from the resulting hydrogenated polymer solution to purify the polymer. Examples of methods that can be used include: 1) continuously removing the solvent from the polymer solution to obtain a concentrated solution, which is then extruded in a molten state while heating to form pellets (also known as devolatilizing extrusion); 2) evaporating the solvent from the polymer solution to obtain a mass, which is then pelletized; 3) adding the polymer solution to a poor solvent, or adding a poor solvent to the polymer solution to cause precipitation, which is then pelletized; and 4) contacting the polymer with hot water to obtain a mass, which is then pelletized. A preferred embodiment of the production method of the present invention involves forming a polymer resin by devolatilizing extrusion after the hydrogenation reaction. Devolatilizing extrusion can be performed, for example, by introducing the polymer solution obtained in a polymerization tank, while maintaining or increasing the temperature to 120°C to 180°C, into a devolatilizing extruder equipped with a vent port and removing the volatile components.

[0065] When separating the catalyst and volatile components, it is desirable to operate under an inert or non-oxidizing gas atmosphere. Hydrogen, nitrogen, helium, and argon can be used as inert or non-oxidizing gases, but industrially, it is desirable to operate under an atmosphere of inexpensive nitrogen or hydrogen, which is a reactive gas.

[0066] The hydrogenation rate (nuclear hydrogenation rate) of the hydrogenated polymer obtained by the method according to one embodiment of the present invention is not particularly limited, but is preferably 90 to 100%, more preferably 95% or more, even more preferably 97% or more, and particularly preferably 98% or more. The hydrogenation rate can be determined by UV spectrum measurement before and after the hydrogenation reaction, as described in the Examples.

[0067] The glass transition temperature (Tgm) of the hydrogenated polymer obtained by the method according to one embodiment of the present invention is not particularly limited, but is preferably 70 to 180° C., more preferably 100 to 160° C. In this specification, the glass transition temperature is a value determined by differential scanning calorimetry (DSC).

[0068] The hydrogenated polymer obtained by the method according to one embodiment of the present invention can be mixed with additives such as antioxidants, colorants, mold release agents, surfactants, and antibacterial agents to form an optical material composition. Because the obtained optical material composition is thermoplastic, optical articles can be produced precisely and economically by various thermoforming processes, such as extrusion molding, injection molding, and secondary processing of sheet-molded articles. Specific applications of the optical articles include various light guide plates and light guides, display front panels, plastic lens substrates, optical filters, optical films, lighting covers, and illuminated signs.

[0069] (Exemplary embodiments) The present invention may include the following exemplary embodiments: [1] A method for producing a hydrogenated polymer by hydrogenating the aromatic rings of an aromatic vinyl compound-based polymer, the method comprising carrying out a hydrogenation reaction using the aromatic vinyl compound-based polymer, a solvent, and a hydrogenation catalyst, the hydrogenation catalyst being a porous catalyst, and the total volume of pores having a pore diameter of 50 to 300 Å of the porous catalyst being 0.17 to 0.50 mL / g. [2] The BET specific surface area of ​​the porous catalyst is 20 to 150 m. ２ / g. [3] The manufacturing method according to [1] or [2], wherein the ratio of the total volume of pores having a pore diameter of less than 30 Å to the total pore volume of the porous catalyst is less than 2.0%. [4] The manufacturing method according to any one of [1] to [3], wherein the porous catalyst comprises a porous support and a metal element. [5] The manufacturing method according to [4], wherein the porous support comprises one or more selected from the group consisting of zirconia, silica, alumina, silica-alumina, activated carbon, and diatomaceous earth. [6] The manufacturing method according to [4] or [5], wherein the metal element is one or more metals or compounds thereof selected from the group consisting of palladium, platinum, ruthenium, rhodium, and nickel. [7] The manufacturing method according to any one of [1] to [6], wherein the aromatic vinyl compound-based polymer comprises one or more selected from the group consisting of a styrene-butadiene copolymer, a styrene-isoprene copolymer, a styrene-methyl methacrylate copolymer, a styrene-maleic anhydride copolymer, a styrene-vinyl acetate copolymer, and polystyrene. [8] The aromatic vinyl compound-based polymer has at least one structure selected from the group consisting of the following (1) to (4): (wherein l and m represent the molar ratio of each structural unit, l is 10 to 100, and m is 90 to 0) (wherein l and m represent the molar ratio of each structural unit, l is 50 to 90, and m is 50 to 10) (wherein l and m represent the molar ratio of each structural unit, l is 80 to 99, and m is 20 to 1) (wherein l and m represent the molar ratios of the respective structural units, l is 80 to 99, and m is 20 to 1). [9] The method for producing an aromatic vinyl compound-based polymer according to any one of [1] to [7], wherein the weight average molecular weight of the aromatic vinyl compound-based polymer is 5×10 ４ ~30 x 10 ４

[10] The method according to any one of [1] to [9], wherein the solvent comprises one or more selected from the group consisting of methyl acetate, ethyl acetate, butyl acetate, methyl isobutyrate, methyl propionate, propylene glycol monomethyl ether acetate, tetrahydrofuran, dioxane, cyclohexane, C7 to C15 monoalkylcyclohexane, C8 to C15 dialkylcyclohexane, C9 to C15 trialkylcyclohexane, C10 to C15 tetraalkylcyclohexane, cyclooctane, C9 to C15 monoalkylcyclooctane, C10 to C15 dialkylcyclooctane, C11 to C15 trialkylcyclooctane, C12 to C15 tetraalkylcyclooctane, n-octane, and n-decane.

[11] The method according to any one of [1] to

[10] , wherein the hydrogenation rate is 90 to 100%.

[12] The method according to any one of [1] to

[11] , wherein the hydrogenation reaction is carried out under conditions of 100 to 200°C for 1 to 50 hours.

[13] The method according to any one of [1] to

[12] , wherein the amount of the hydrogenation catalyst added is 0.01 to 0.3 times the weight of the aromatic vinyl compound-based polymer.

[0070] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The resins were evaluated as follows: (1) The hydrogenation rate was determined by measuring UV spectra before and after the hydrogenation reaction. That is, the resin was dissolved in tetrahydrofuran (THF) as a solvent, and the absorption spectrum at 260 nm was measured using a quartz cell. The copolymer resin before the hydrogenation reaction was used to calculate the proportion of unhydrogenated aromatic rings. The measurement was performed using a Thermo UV-Visible Spectrophotometer "GENESYS 10S," but any equivalent device can be used. (2) The weight-average molecular weight (Mw) was determined by gel permeation chromatography (GPC). A differential refractive index (RI) detector was used, and THF was used as the solvent, followed by calibration with standard polystyrene. The measurement was performed using a Shimadzu Science High-Performance Liquid Chromatography System "Elite LaChrom," but any equivalent device can be used. (3) Pore volume (BJH method) and BET specific surface area were determined by measurement using the nitrogen adsorption method. Measurements were performed at 77 K (-196 °C) using samples degassed by vacuum drying at 200 °C for 2 hours. Pore volume was measured by plotting 40 points for adsorption and desorption over a relative pressure range (P / saturated vapor pressure) of 0.2 to 1. The instrument used for the measurement was an Anton Paar gas adsorption analyzer "AS-6," but any equivalent instrument may be used.

[0071] Preparation Example: Preparation of Hydrogenation Catalysts Various hydrogenation catalysts (Catalysts 1 to 10) were prepared prior to the hydrogenation reaction. The catalysts were prepared using various porous supports and palladium chloride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) as shown in Table 1 below. Supports A to C are zirconia supports (product number: Z-3345) manufactured by Daiichi Kigenso Kagaku Kogyo Co., Ltd., and were calcined at different temperatures as shown in the table below. Support D is a zirconia support (product number: Z-3690) manufactured by Daiichi Kigenso Kagaku Kogyo Co., Ltd. Commercially available supports 1 to 3 were selected from zirconia supports generally available on the market, and prototype supports 1 to 4 were zirconia supports prepared to have the desired pore characteristics.

[0072] The catalyst was prepared according to the following procedure. First, 6 g of water and 56 g of a 0.5 wt % aqueous solution of sodium bicarbonate were added to 2.94 g of carrier A, and the mixture was stirred at 40°C for 0.5 hours. 0.1 g of palladium chloride was dissolved in 11.28 mL of a 0.1 mol / L aqueous solution of hydrochloric acid, and the resulting solution was added dropwise to the carrier. The carrier was impregnated with the solution while stirring at 40°C for 0.5 hours. The resulting catalyst slurry was filtered, washed with pure water, dried at 120°C for 10 hours, and calcined at 400°C for 3 hours to obtain 2.0 wt % Pd / ZrO. ２ The same procedure was carried out for carriers B, C, D, commercial carriers 1 to 3, and prototype carriers 1 to 3 to prepare 2.0 wt % Pd / ZrO catalysts. ２ The specific surface area and pore properties of the catalyst obtained are shown in the table below.

[0073] [Hydrogenation of MS Resin] Example 1: Hydrogenation reaction of MS resin (MS750) (using catalyst 1) One part by weight of MS resin (manufactured by Toyo Styrene, MS750) having a weight average molecular weight of 135,000 was dissolved in 4 parts by weight of methyl isobutyrate (manufactured by Tokyo Chemical Industry, hereinafter referred to as IBM) to prepare a raw polymer solution for the hydrogenation reaction. The raw polymer solution was mixed with catalyst 1 (2.0 wt % Pd / ZrO ２ ) was charged into a reaction vessel equipped with a stirrer, pressurized to a hydrogen pressure of 6.5 MPa / G at room temperature, and then hydrogenation reaction was carried out at a temperature of 150°C for 7 hours. After the reaction, the mixture was allowed to cool to room temperature, hydrogen was purged, and the pressure was reduced. Five parts by weight of IBM was added to dilute the mixture, and the catalyst was then removed by filtration. This resin solution was added dropwise to excess methanol to precipitate the resin. The resulting resin powder was dried under reduced pressure to obtain a dry resin powder. The hydrogenation rate of this hydrogenated polymer was 93.1%. The hydrogenation time was then extended to 15 hours, and the hydrogenation rate reached 99.7%.

[0074] Example 2: Hydrogenation reaction of MS resin (MS750) (using catalyst 2) The hydrogenation reaction was carried out in the same manner as in Example 1, except that catalyst 1 was replaced with catalyst 2. The hydrogenation rate of the obtained resin after 7 hours was 99.9%.

[0075] Example 3: Hydrogenation reaction of MS resin (MS750) (using catalyst 3) A hydrogenation reaction was carried out in the same manner as in Example 1, except that catalyst 1 was replaced with catalyst 3. The hydrogenation rate of the obtained resin after 7 hours was 92.9%.

[0076] Example 4: Hydrogenation reaction of MS resin (MS750) (using catalyst 4) A hydrogenation reaction was carried out in the same manner as in Example 1, except that catalyst 1 was replaced with catalyst 4. The hydrogenation rate of the obtained resin after 7 hours was 99.9%.

[0077] Examples 5-10: Hydrogenation of MS Resin (MS750) (Using Catalysts Prepared from Commercial Carriers or Prototype Carriers) Hydrogenation reactions were carried out in the same manner as in Example 1, except that Catalyst 1 was replaced with Catalysts 5-10, which were prepared from either Commercial Carriers 1-3 or Prototype Carriers 1-3. The hydrogenation rates of the resulting resins were as follows: Catalyst 5 (99.6%), Catalyst 6 (74.2%), Catalyst 7 (99.6%), Catalyst 8 (65.5%), Catalyst 9 (78.0%), and Catalyst 10 (not shown). Furthermore, when the hydrogenation time was extended to 15 hours for the catalysts prepared using Prototype Carriers 1 and 3 and Commercial Carriers 2 and 3 (Catalysts 6, 8, 9, and 10) in the same manner as in Example 1, the hydrogenation rates were as follows: Catalyst 6 (97.6%), Catalyst 8 (over 99%), Catalyst 9 (over 99%), and Catalyst 10 (96.1%).

[0078] The results obtained are summarized in Table 2 below.

[0079] [Hydrogenation of Various Resins] Next, various resins were hydrogenated using catalyst 1 and catalyst 2. The resins used were as follows: methyl methacrylate-styrene copolymer (MS resin (resin of formula (1)), manufactured by Toyo Styrene, MS750 (weight average molecular weight 135,000), MS600 (weight average molecular weight 160,000), MS500 (weight average molecular weight 127,000), MS200 (weight average molecular weight 258,000)), polystyrene resin (PS resin (resin in which l is 100 in formula (1)), manufactured by PS Japan, GPPS HF-77 (weight average molecular weight 244,000)), styrene-butadiene copolymer resin (SBC resin (resin of formula (2)), manufactured by Denka, Clearen 530L (weight average molecular weight 133,000)), styrene-maleic anhydride copolymer resin (SMA resin (resin of formula (3)), POLYSCOPE POLYMERS XIBOND120 (weight average molecular weight 177,000) manufactured by BV Co., Ltd. and styrene-vinyl acetate copolymer resin (resin of formula (4), MODIPER SV10B (weight average molecular weight 196,000) manufactured by NOF Corporation).

[0080] Example 11: Hydrogenation reaction of MS resin (MS750) One part by weight of MS resin (manufactured by Toyo Styrene, MS750) having a weight average molecular weight of 135,000 was dissolved in 4 parts by weight of IBM to prepare a raw polymer solution for hydrogenation reaction. The raw polymer solution was mixed with catalyst 1 or 2 (2.0 wt % Pd / ZrO) prepared from carrier A or carrier B. ２ ) was charged into a reaction vessel equipped with a stirrer, and the mixture was pressurized to a hydrogen pressure of 6.5 MPa / G at room temperature, followed by a hydrogenation reaction at a temperature of 150°C for 7 hours. After the reaction, the mixture was allowed to cool to room temperature, hydrogen was purged, the pressure was reduced, and 5 parts by weight of IBM was added to dilute the mixture, followed by filtration to remove the catalyst. This resin solution was added dropwise to excess methanol to precipitate the resin. The resulting resin powder was dried under reduced pressure to obtain a dry resin powder. The hydrogenation rate of the hydrogenated polymer using catalyst 1 obtained from carrier A was 93.1%, and the hydrogenation rate of the hydrogenated polymer using catalyst 2 obtained from carrier B was 99.9%.

[0081] Example 12: Hydrogenation of MS resin (MS600) A hydrogenation reaction was carried out in the same manner as in Example 11, except that MS resin (manufactured by Toyo Styrene, MS750) was replaced with MS resin (manufactured by Toyo Styrene, MS600). The hydrogenation rate of the hydrogenated polymer using catalyst 1 obtained from carrier A was 89.5%, and the hydrogenation rate of the hydrogenated polymer using catalyst 2 obtained from carrier B was 97.9%.

[0082] Example 13: Hydrogenation of MS resin (MS500) A hydrogenation reaction was carried out in the same manner as in Example 11, except that MS resin (manufactured by Toyo Styrene, MS750) was replaced with MS resin (manufactured by Toyo Styrene, MS500). The hydrogenation rate of the hydrogenated polymer using catalyst 1 obtained from carrier A was 67.9%, and the hydrogenation rate of the hydrogenated polymer using catalyst 2 obtained from carrier B was 77.1%.

[0083] Example 14: Hydrogenation of MS resin (MS200) A hydrogenation reaction was carried out in the same manner as in Example 11, except that MS resin (manufactured by Toyo Styrene, MS750) was replaced with MS resin (manufactured by Toyo Styrene, MS200) and the solvent was changed from IBM to a mixed solvent of IBM and cyclohexane (manufactured by Tokyo Chemical Industry Co., Ltd., hereinafter referred to as CH) (weight ratio of IBM to CH:1). The hydrogenation rate of the hydrogenated polymer using catalyst 1 obtained from carrier A was 50.1%, and the hydrogenation rate of the hydrogenated polymer using catalyst 2 obtained from carrier B was 63.1%.

[0084] Example 15: Hydrogenation reaction of PS resin 0.5 parts by weight of PS resin (GPPS HF-77, manufactured by PS Japan Co., Ltd.) having a weight average molecular weight of 244,000 was dissolved in 4.5 parts by weight of a mixed solvent of IBM and CH (weight ratio 1:1) to prepare a raw polymer solution for hydrogenation reaction. The raw polymer solution was mixed with a catalyst (2.0 wt % Pd / ZrO ２) was charged into a reaction vessel equipped with a stirrer, and the mixture was pressurized to a hydrogen pressure of 6.5 MPa / G at room temperature, followed by a hydrogenation reaction at a temperature of 180°C for 18 hours. After the reaction, the mixture was allowed to cool to room temperature, hydrogen was purged, the pressure was reduced, and 5 parts by weight of IBM was added to dilute the mixture, followed by filtration to remove the catalyst. This resin solution was added dropwise to excess isopropanol to precipitate a resin. The resulting resin powder was dried under reduced pressure to obtain a dry resin powder. The hydrogenation rate of the hydrogenated polymer using catalyst 1 obtained from carrier A was 99.2%, and the hydrogenation rate of the hydrogenated polymer using catalyst 2 obtained from carrier B was 99.5%.

[0085] Example 16: Hydrogenation of SBC resin The hydrogenation reaction was carried out in the same manner as in Example 15, except that the PS resin was replaced with an SBC resin having a weight-average molecular weight of 133,000 (Clearene 530L, manufactured by Denka Company Limited) and the reaction time was extended to 24 hours. The hydrogenation rate of the hydrogenated polymer using catalyst 1 obtained from carrier A was 70.1%, and the hydrogenation rate of the hydrogenated polymer using catalyst 2 obtained from carrier B was 99.4%.

[0086] Example 17: Hydrogenation reaction of SMA resin A hydrogenation reaction was carried out in the same manner as in Example 15, except that the PS resin was replaced with an SMA resin having a weight-average molecular weight of 177,000 (XIBOND 120, manufactured by POLYSCOPE POLYMERS B.V.) and the reaction time was extended to 28 hours. The hydrogenation rate of the hydrogenated polymer using catalyst 1 obtained from carrier A was 99.0%, and the hydrogenation rate of the hydrogenated polymer using catalyst 2 obtained from carrier B was 99.6%.

[0087] Example 18: Hydrogenation of styrene-vinyl acetate copolymer resin The hydrogenation reaction was carried out in the same manner as in Example 15, except that the PS resin was replaced with a styrene-vinyl acetate copolymer resin (MODIPER SV10B, manufactured by NOF Corporation) having a weight average molecular weight of 196,000, the solvent was changed from a mixed solvent of IBM and CH to a mixed solvent of methyl propionate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., hereinafter referred to as MP) and CH (weight ratio 1:1), and the reaction time was extended to 22 hours. The hydrogenation rate of the hydrogenated polymer using catalyst 1 obtained from carrier A was 96.1%, and the hydrogenation rate of the hydrogenated polymer using catalyst 2 obtained from carrier B was 97.5%.

[0088] The results obtained are summarized in Table 3.

Claims

1. A method for producing a hydrogenated polymer by hydrogenating the aromatic rings of an aromatic vinyl compound-based polymer, comprising carrying out a hydrogenation reaction using the aromatic vinyl compound-based polymer, a solvent, and a hydrogenation catalyst, wherein the hydrogenation catalyst is a porous catalyst, and the total volume of pores having a pore diameter of 50 to 300 Å of the porous catalyst is 0.17 to 1.00 mL / g.

2. The BET specific surface area of ​​the porous catalyst is 20 to 150 m ２ The method according to claim 1, wherein the SiO2 content is 1 / g.

3. The method according to claim 1 or 2, wherein the ratio of the total volume of pores having a pore diameter of less than 30 Å to the total pore volume of the porous catalyst is less than 2.0%.

4. The method according to any one of claims 1 to 3, wherein the porous catalyst comprises a porous support and a metal element.

5. The method of claim 4, wherein the porous support comprises one or more selected from the group consisting of zirconia, silica, alumina, silica-alumina, activated carbon, and diatomaceous earth.

6. The method according to claim 4 or 5, wherein the metal element is one or more metals selected from the group consisting of palladium, platinum, ruthenium, rhodium and nickel, or compounds thereof.

7. The method according to any one of claims 1 to 6, wherein the aromatic vinyl compound polymer comprises at least one selected from the group consisting of a copolymer of styrene and butadiene, a copolymer of styrene and isoprene, a copolymer of styrene and methyl methacrylate, a copolymer of styrene and maleic anhydride, a copolymer of styrene and vinyl acetate, and polystyrene.

8. The aromatic vinyl compound polymer has at least one structure selected from the group consisting of the following (1) to (4): (wherein l and m represent the molar ratio of each structural unit, l is 10 to 100, and m is 90 to 0) (wherein l and m represent the molar ratio of each structural unit, l is 50 to 90, and m is 50 to 10) (wherein l and m represent the molar ratio of each structural unit, l is 80 to 99, and m is 20 to 1) (wherein l and m represent the molar ratio of each constituent unit, l is 80 to 99, and m is 20 to 1), 9. The weight average molecular weight of the aromatic vinyl compound polymer is 5×10 ４ ~30 x 10 ４ The method according to any one of claims 1 to 8, wherein 10. The process according to any one of claims 1 to 9, wherein the solvent comprises one or more selected from the group consisting of methyl acetate, ethyl acetate, butyl acetate, methyl isobutyrate, methyl propionate, propylene glycol monomethyl ether acetate, tetrahydrofuran, dioxane, cyclohexane, C7 to C15 monoalkylcyclohexane, C8 to C15 dialkylcyclohexane, C9 to C15 trialkylcyclohexane, C10 to C15 tetraalkylcyclohexane, cyclooctane, C9 to C15 monoalkylcyclooctane, C10 to C15 dialkylcyclooctane, C11 to C15 trialkylcyclooctane, C12 to C15 tetraalkylcyclooctane, n-octane, and n-decane.

11. The production method according to any one of claims 1 to 10, wherein the hydrogenation rate is 90 to 100%.

12. The method according to any one of claims 1 to 11, wherein the hydrogenation reaction is carried out at 100 to 200°C for 1 to 50 hours.

13. The method of any one of claims 1 to 12, wherein the amount of the hydrogenation catalyst added is 0.01 to 0.3 times the weight of the aromatic vinyl compound polymer.

14. The method according to any one of claims 1 to 13, wherein the total volume of pores in the porous catalyst having a pore diameter of 50 to 300 Å is 0.17 to 0.50 mL / g.

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