Method for producing cyclic olefin copolymer

Abstract

A method for producing a cycloolefin copolymer, wherein the cycloolefin copolymer contains a structural unit derived from a norbornene monomer and a structural unit derived from ethylene, wherein the method for producing the cycloolefin copolymer comprises: a charging step of charging at least a monomer containing a norbornene monomer and ethylene and hydrogen into a polymerization container; and a polymerization step of polymerizing the monomers in the polymerization container in the presence of hydrogen and a catalyst having a phosphinimide group, wherein the molecular weight of the cycloolefin copolymer produced by the polymerization step is controlled by adjusting the concentration of hydrogen charged into the polymerization container.

Description

Technical Field

[0001] The present invention relates to a method for producing a cycloolefin copolymer. Background Art

[0002] Cycloolefin homopolymers and cycloolefin copolymers have low hygroscopicity and high transparency, and are used in various applications, including in the field of optical materials such as optical disk substrates, optical films, and optical fibers.

[0003] As a representative cycloolefin copolymer, there is a copolymer of cycloolefin and ethylene which is widely used as a transparent resin. Since the glass transition temperature (Tg) of the copolymer of cycloolefin and ethylene can be changed according to the copolymerization composition of the cycloolefin and ethylene, it is possible to produce a copolymer whose glass transition temperature can be adjusted in a wide temperature range (for example, refer to Non-Patent Document 1).

[0004] Prior art literature

[0005] Non-patent literature

[0006] Non-patent document 1: Incoronata, Tritto et al., Coordination Chemistry Reviews, 2006, Vol. 250, pp. 212-241 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, the method described in non-patent literature 1 has the problem that a copolymer of cyclic olefin and ethylene cannot be produced in high yield. As a solution to this problem, it is possible to use a highly active catalyst to polymerize. However, when a highly active catalyst is used to polymerize, it is difficult to control the molecular weight of the generated copolymer, and a copolymer with excessively high molecular weight is often obtained.

[0009] In addition, when using a highly active catalyst for polymerization, there is a situation where polyethylene-like impurities are easily generated. When the cycloolefin copolymer contains polyethylene-like impurities, turbidity is generated when the cycloolefin copolymer is dissolved in a solvent. Therefore, there is a concern that the transparency of the cycloolefin copolymer will decrease. And, when polyethylene-like impurities are generated, in the general manufacturing process of manufacturing the cycloolefin copolymer, it is necessary to filter and remove insoluble polyethylene-like impurities and the like, which causes an increase in manufacturing cost.

[0010] That is, in the conventional production method, it is difficult to produce cycloolefin copolymers at high yield, suppress the generation of polyethylene-like impurities, and control the molecular weight of the produced cycloolefin copolymers. It would be useful if the produced cycloolefin copolymers could be controlled to a desired molecular weight.

[0011] The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a method for producing a cycloolefin copolymer containing a structural unit derived from a norbornene monomer and a structural unit derived from ethylene, in which the generation of polyethylene-like impurities is suppressed and the molecular weight of the produced cycloolefin copolymer is controlled, thereby achieving good yield.

[0012] Technical solutions to solve problems

[0013] The present inventors have conducted intensive studies to solve the above problems and have found that in the copolymerization of norbornene monomer and ethylene in the presence of a catalyst having a phosphine imide group, by allowing hydrogen to coexist and adjusting the hydrogen concentration, the molecular weight of the produced cycloolefin copolymer can be controlled, thereby achieving the present invention.

[0014] One aspect of the present invention for solving the above-mentioned problems is as follows.

[0015] (1) A method for producing a cycloolefin copolymer, wherein the cycloolefin copolymer comprises a structural unit derived from a norbornene monomer and a structural unit derived from ethylene, wherein:

[0016] The method for producing the cycloolefin copolymer comprises:

[0017] a charging step of charging at least a monomer containing norbornene monomer and ethylene and hydrogen into a polymerization container; and

[0018] a polymerization step of polymerizing the monomer in the polymerization container in the presence of the hydrogen and a catalyst having a phosphinimide group,

[0019] The molecular weight of the cycloolefin copolymer produced in the polymerization step is controlled by adjusting the concentration of hydrogen charged into the polymerization container.

[0020] (2) The method for producing a cycloolefin copolymer according to (1) above, wherein the concentration of hydrogen charged into the polymerization vessel in the next charging step is set according to the following condition (A) or the following condition (B) based on the molecular weight of the cycloolefin copolymer obtained in one polymerization step.

[0021] Condition (A): When the molecular weight of the cycloolefin copolymer produced in the polymerization step is larger than a desired molecular weight, the concentration of hydrogen charged into the polymerization container is increased in the next charging step.

[0022] Condition (B): When the molecular weight of the cycloolefin copolymer produced in the polymerization step is lower than the desired molecular weight, the concentration of hydrogen charged into the polymerization container is reduced in the next charging step.

[0023] (3) The method for producing a cycloolefin copolymer according to (1) or (2) above, wherein the catalyst having the phosphinimide group is a metal-containing compound having a group represented by the following formula (a1):

[0024] [Chemical formula 1]

[0025]

[0026] [In formula (a1), M is Ti, Zr or Hf, X is an organic substituent having 1 to 20 carbon atoms which may contain a hetero atom or a halogen atom, and L 1 is a group represented by the following formula (a1a) or the following formula (a1b),

[0027] [Chemical formula 2]

[0028]

[0029] In formula (a1a), R a1 ~R a5 Each independently represents a hydrogen atom which may be the same or different, an organic substituent having 1 to 20 carbon atoms which may contain a heteroatom, or an inorganic substituent, and in R a1 ~R a5 The two adjacent groups on the 5-membered ring can combine with each other to form a ring.

[0030] In formula (a1b), R a6 ~R a8 Each independently represents a hydrogen atom which may be the same or different, an organic substituent having 1 to 20 carbon atoms which may contain a heteroatom, or an inorganic substituent selected from R a6 ~R a8 The two groups can combine to form a ring.

[0031] L 2 is a group represented by the above formula (a1b). ].

[0032] (4) The method for producing a cycloolefin copolymer according to (3) above, wherein in the formula (a1), M is Ti.

[0033] (5) The method for producing a cycloolefin copolymer according to any one of (1) to (4) above, wherein the polymerization of the monomer is performed in the presence of the catalyst having a phosphinidiide group and a co-catalyst.

[0034] (6) The method for producing a cycloolefin copolymer according to (5) above, wherein the co-catalyst contains at least one of an aluminoxane and a borate compound.

[0035] (7) The method for producing a cycloolefin copolymer according to any one of (1) to (6) above, wherein the polymerization of the monomer is carried out in the presence of a hydrocarbon solvent.

[0036] (8) A method for producing a cycloolefin copolymer according to any one of (1) to (7), wherein a sample of the cycloolefin copolymer is measured by a differential scanning calorimeter under a nitrogen atmosphere at a heating rate of 20°C / min according to the method described in JIS K7121, and the obtained DSC curve does not have a melting point peak derived from polyethylene-like impurities in the range of 100°C to 140°C.

[0037] (9) The method for producing a cycloolefin copolymer according to any one of (1) to (8), wherein the cycloolefin copolymer has a molecular weight distribution (Mw / Mn) of 3.0 or less.

[0038] Effects of the Invention

[0039] According to the present invention, in a method for producing a cycloolefin copolymer containing a structural unit derived from a norbornene monomer and a structural unit derived from ethylene, it is possible to provide a method for producing a cycloolefin copolymer with good yield, in which the generation of polyethylene-like impurities can be suppressed and the molecular weight of the produced cycloolefin copolymer can be controlled. DETAILED DESCRIPTION

[0040] The method for producing a cycloolefin copolymer of the present embodiment is a method for producing a cycloolefin copolymer containing a structural unit derived from a norbornene monomer and a structural unit derived from ethylene, comprising: a charging step of charging at least a monomer containing a norbornene monomer and ethylene and hydrogen into a polymerization container; and a polymerization step of polymerizing the monomers in the polymerization container in the presence of hydrogen and a catalyst having a phosphinimide group. Then, the molecular weight of the cycloolefin copolymer produced by the polymerization step is controlled by adjusting the concentration of hydrogen charged into the polymerization container.

[0041] In addition, in this embodiment, "molecular weight" includes both weight average molecular weight and number average molecular weight.

[0042] In the method for producing a cycloolefin copolymer of the present embodiment, in the copolymerization of norbornene monomer and ethylene, a catalyst having a predetermined phosphinimide group is present and hydrogen is coexisted to adjust the concentration of the hydrogen, thereby controlling the molecular weight of the generated cycloolefin copolymer. By using hydrogen to replace the organic metal compound such as organic aluminum commonly used, the amount of metal used in the polymerization reaction can be reduced. However, in the method for producing a cycloolefin copolymer in which a catalyst having a predetermined phosphinimide group is present, there are many unknown parts in the molecular weight adjustment method using hydrogen. That is, it is generally assumed that the catalyst for cycloolefin copolymerization activated by a boron compound such as a borate is unstable, and the catalyst used in the present embodiment also undergoes undesirable side reactions such as the reduction of the double bond of P=N by hydrogen. However, the inventors have found that hydrogen can actually coexist, and the molecular weight of the generated cycloolefin copolymer can be controlled by adjusting the concentration of hydrogen. Moreover, even if the molecular weight is controlled in this way, the catalyst activity is maintained at a high level, and it is easy to produce with a good yield.

[0043] In addition, generally, when ethylene and norbornene monomers are copolymerized in the presence of a highly active catalyst, the polymerization of ethylenes is easy to proceed, and polyethylene-like impurities are easy to generate. However, when a catalyst having a predetermined phosphinimide group is used, the generation of polyethylene-like impurities is suppressed and a cycloolefin copolymer is easy to produce with a good yield.

[0044] As described above, in the method for producing a cycloolefin copolymer according to the present embodiment, the yield is good, the generation of polyethylene-like impurities is suppressed, and the molecular weight of the produced cycloolefin copolymer can be controlled.

[0045] <Loading process>

[0046] In the charging step, monomers containing norbornene monomers and ethylene and hydrogen are charged into the polymerization container. In the polymerization container, other monomers other than norbornene monomers and ethylene may be charged within the range that has no adverse effect on the production method of the present embodiment. The total ratio of the structural unit derived from the norbornene monomer and the structural unit derived from ethylene in the cycloolefin copolymer is typically preferably 80% by mass or more, more preferably 95% by mass or more, and further preferably 98% by mass or more relative to the total structural units.

[0047] The method for loading ethylene into the polymerization solution is not particularly limited as long as the desired amount of ethylene is loaded into the polymerization container. Typically, ethylene is loaded into the polymerization container in a manner such that the loading pressure of ethylene in the polymerization container is 0.5 MPa or more. The loading pressure of ethylene is preferably 0.55 MPa or more, more preferably 0.6 MPa or more. When the loading pressure of ethylene is increased, the amount of catalyst used per generated polymer can be reduced. Regarding the upper limit, the loading pressure of ethylene is, for example, preferably 10 MPa or less, more preferably 5 MPa or less, and further preferably 3 MPa or less.

[0048] In addition, in the manufacturing method of the present embodiment, the molecular weight of the cycloolefin copolymer generated by the polymerization process of the next process is controlled by adjusting the concentration of hydrogen loaded into the polymerization container. Therefore, the concentration of hydrogen loaded into the polymerization container is adjusted according to the molecular weight of the desired cycloolefin copolymer. For example, in the case of obtaining a cycloolefin copolymer with a molecular weight larger than the molecular weight of the cycloolefin copolymer obtained through a series of processes of the manufacturing method of the present embodiment, it is sufficient to make the concentration of hydrogen loaded into the polymerization container in the newly set loading process lower than the concentration of hydrogen in the loading process so far. On the contrary, in the case of obtaining a cycloolefin copolymer with a molecular weight smaller than the molecular weight of the cycloolefin copolymer obtained through a series of processes, it is sufficient to make the concentration of hydrogen loaded into the polymerization container in the newly set loading process higher than the concentration of hydrogen in the loading process so far. That is, based on the molecular weight of the cycloolefin copolymer obtained by a polymerization process, in the next loading process, the concentration of hydrogen loaded into the polymerization container can be set according to the following conditions (A) or the following conditions (B).

[0049] Condition (A): When the molecular weight of the cycloolefin copolymer produced in the polymerization step is larger than the desired molecular weight, the concentration of hydrogen charged into the polymerization vessel is increased in the next charging step.

[0050] Condition (B): When the molecular weight of the cycloolefin copolymer produced in the polymerization step is lower than the desired molecular weight, the concentration of hydrogen charged into the polymerization vessel is reduced in the next charging step.

[0051] How much the molecular weight of the cycloolefin copolymer changes according to the change in the concentration of hydrogen charged into the polymerization vessel can be known by conducting multiple experiments in advance for the charging process and the polymerization process. Then, based on such experimental results, a relational expression for the change in the molecular weight of the cycloolefin copolymer with respect to the change in hydrogen concentration is derived, a calibration curve is prepared, etc., and these can be used to determine the concentration of hydrogen that should be charged into the polymerization vessel in order to obtain a cycloolefin copolymer with a desired molecular weight.

[0052] On the other hand, the cycloolefin copolymer obtained by the manufacturing method of this embodiment has a molecular weight reduced by adding hydrogen in the charging step, so that it has a molecular weight above a certain level when hydrogen is not added, and the molecular weight can be controlled in a wider range, which is preferred. In addition, the molecular weight of the cycloolefin copolymer can be adjusted by selecting the catalyst used.

[0053] The cycloolefin copolymer obtained by the production method of this embodiment may have a weight average molecular weight (Mw) of, for example, 30,000 to 600,000, and a number average molecular weight (Mn) of, for example, 10,000 to 200,000. In order to obtain good mechanical properties, the molecular weight distribution (Mw / Mn) is preferably 3.0 or less.

[0054] In the polymerization container, a solvent may also be loaded together with the norbornene monomer, ethylene and hydrogen. As a solvent, there is no particular limitation as long as it is a solvent that does not interfere with the polymerization reaction. As preferred solvents, for example, hydrocarbon solvents and halogenated hydrocarbon solvents may be listed. From the perspective of excellent handling, thermal stability and chemical stability, hydrocarbon solvents are preferred. As specific examples of preferred solvents, hydrocarbon solvents such as pentane, hexane, heptane, octane, isooctane, isododecane, mineral oil, cyclohexane, methylcyclohexane, decahydronaphthalene (decahydronaphthalene), benzene, toluene, and xylene, and halogenated hydrocarbon solvents such as chloroform, methylene chloride, dichloromethane, ethylene dichloride and chlorobenzene may be listed.

[0055] When the norbornene monomer is charged into the solvent, the lower limit of the concentration of the norbornene monomer is, for example, preferably 0.5 mass % or more, more preferably 10 mass % or more, and the upper limit is, for example, preferably 50 mass % or less, more preferably 35 mass % or less.

[0056] The norbornene monomer is described below.

[0057] [Norbornene monomer]

[0058] Examples of the norbornene monomer include norbornene and substituted norbornene, and norbornene is preferred. The norbornene monomer may be used alone or in combination of two or more.

[0059] The substituted norbornene is not particularly limited, and examples of the substituent possessed by the substituted norbornene include a halogen atom and a monovalent or divalent hydrocarbon group. Specific examples of the substituted norbornene include compounds represented by the following general formula (I).

[0060] [Chemical formula 3]

[0061]

[0062] [In the general formula (I), R 1 ~R 12 are each the same or different and selected from the group consisting of a hydrogen atom, a halogen atom and a hydrocarbon group,

[0063] R 9 and R 10 , R 11 and R 12 Can form a divalent hydrocarbon group integrally,

[0064] R 9 or R 10 With R 11 or R 12 Can form a loop with each other.

[0065] In addition, n represents 0 or a positive integer,

[0066] When n is 2 or more, R 5 ~R 8 In each repeating unit, they may be the same or different.

[0067] However, when n = 0, R 1 ~R 4 and R 9 ~R 12 At least one of them is not a hydrogen atom.]

[0068] The substituted norbornene represented by the general formula (I) is described below. 1 ~R 12 They may be the same or different and are selected from the group consisting of a hydrogen atom, a halogen atom and a hydrocarbon group.

[0069] As R 1 ~R 8 Specific examples include hydrogen atoms; halogen atoms such as fluorine, chlorine, and bromine; and alkyl groups having 1 to 20 carbon atoms. These may be different from each other, may be partially different, or may be all the same.

[0070] In addition, as R 9 ~R 12 Specific examples include a hydrogen atom; a halogen atom such as fluorine, chlorine, or bromine; an alkyl group having 1 to 20 carbon atoms; a cycloalkyl group such as a cyclohexyl group; a substituted or unsubstituted aromatic hydrocarbon group such as a phenyl group, a tolyl group, an ethylphenyl group, an isopropylphenyl group, a naphthyl group, an anthracenyl group, etc.; a benzyl group, a phenethyl group, and other aralkyl groups in which an aryl group is substituted with an alkyl group, and these groups may be different from each other, may be partially different, or may be all the same.

[0071] As R 9 With R10 or R 11 With R 12 Specific examples of the case where the groups are integrated to form a divalent hydrocarbon group include alkylene groups such as ethylene, propylene, and isopropylene.

[0072] In R 9 or R 10 With R 11 or R 12 When the rings are formed, the formed rings may be monocyclic or polycyclic, may be cross-linked polycyclic, may be a ring having double bonds, or may be a ring composed of a combination of these rings. In addition, these rings may also have substituents such as methyl.

[0073] Specific examples of the substituted norbornene represented by the general formula (I) include bicyclic olefins such as 5-methyl-bicyclo[2.2.1]hept-2-ene, 5,5-dimethyl-bicyclo[2.2.1]hept-2-ene, 5-ethyl-bicyclo[2.2.1]hept-2-ene, 5-butyl-bicyclo[2.2.1]hept-2-ene, 5-ethylidene-bicyclo[2.2.1]hept-2-ene, 5-hexyl-bicyclo[2.2.1]hept-2-ene, 5-octyl-bicyclo[2.2.1]hept-2-ene, 5-octadecyl-bicyclo[2.2.1]hept-2-ene, 5-methylene-bicyclo[2.2.1]hept-2-ene, 5-vinyl-bicyclo[2.2.1]hept-2-ene and 5-propenyl-bicyclo[2.2.1]hept-2-ene;

[0074] Tricyclic [4.3.0.1 2,5 ]Deca-3,7-diene (common name: dicyclopentadiene), tricyclo[4.3.0.1 2,5 ]Deca-3-ene; tricyclo[4.4.0.1 2,5 ] undec-3,7-diene or tricyclo[4.4.0.1 2,5 ] undec-3,8-diene or their partial hydrogenation products (or the adducts of cyclopentadiene and cyclohexene), namely tricyclo[4.4.0.1 2,5 ] undec-3-ene; tricyclic cyclic olefins such as 5-cyclopentyl-bicyclo[2.2.1]hept-2-ene, 5-cyclohexyl-bicyclo[2.2.1]hept-2-ene, 5-cyclohexenylbicyclo[2.2.1]hept-2-ene, and 5-phenyl-bicyclo[2.2.1]hept-2-ene;

[0075] Four Rings [4.4.0.1 2,5 .1 7,10 ] dodeca-3-ene (referred to as tetracyclododecene), 8-methyltetracyclo[4.4.0.1 2, 5 .1 7,10] dodeca-3-ene, 8-ethyltetracyclo[4.4.0.1 2,5 .1 7,10 ] dodeca-3-ene, 8-methylenetetracyclo[4.4.0.1 2,5 .1 7 ,10 ] dodeca-3-ene, 8-ethylenetetracyclo[4.4.0.1 2,5 .1 7,10 ] dodeca-3-ene, 8-vinyltetracyclo[4,4.0.1 2,5 .1 7 ,10 ] dodeca-3-ene, 8-propenyl-tetracyclo[4.4.0.1 2,5 .1 7,10 ] 4-ring cyclic olefins such as dodeca-3-ene;

[0076] 8-Cyclopentyl-tetracyclo[4.4.0.1 2,5 .1 7,10 ] dodeca-3-ene, 8-cyclohexyl-tetracyclo[4.4.0.1 2,5 .1 7,10 ] dodeca-3-ene, 8-cyclohexenyl-tetracyclo[4.4.0.1 2,5 .1 7,10 ] dodeca-3-ene, 8-phenyl-cyclopentyl-tetracyclo[4.4.0.1 2 ,5 .1 7,10 ] dodeca-3-ene; tetracyclo[7.4.1 3,6 .0 1,9 .0 2,7 ]Tetradeca-4,9,11,13-tetraene (also known as 1,4-methano-1,4,4a,9a-tetrahydrofluorene), tetracyclo[8.4.1 4,7 .0 1,10 .0 3,8 ]pentadeca-5,10,12,14-tetraene (also known as 1,4-methano-1,4,4a,5,10,10a-hexahydroanthracene); pentacyclic [6.6.1.1 3,6 .0 2,7 .0 9,14 ]-4-hexadecene, pentacyclic [6.5.1.1 3, 6 .0 2,7 .0 9,13 ]-4-pentadecene, pentacyclo[7.4.0.0 2,7 .1 3,6 .1 10,13 ]-4-pentadecene; heptacyclo[8.7.0.1 2,9 .1 4,7 .1 11,17 .0 3,8 .0 12,16 ]-5-eicosene, heptacyclic [8.7.0.1 2,9 .0 3,8 .1 4,7 .0 12,17 .1 13,l6 ]-14-eicosene; a polycyclic cyclic olefin such as a tetramer of cyclopentadiene.

[0077] Among them, alkyl-substituted norbornene (e.g., bicyclo[2.2.1]hept-2-ene substituted with one or more alkyl groups) and alkylidene-substituted norbornene (e.g., bicyclo[2.2.1]hept-2-ene substituted with one or more alkylidene groups) are preferred, and 5-ethylidene-bicyclo[2.2.1]hept-2-ene (common name: 5-ethylidene-2-norbornene or simply ethylidene norbornene) is particularly preferred.

[0078] The monomers other than the norbornene monomer and ethylene are not particularly limited as long as they can be copolymerized with the norbornene monomer and ethylene. Typical examples of the other monomers involved include α-olefins. The α-olefins may be substituted with at least one substituent such as a halogen atom.

[0079] As α-olefin, C3 to C12 α-olefin is preferred. C3 to C12 α-olefin is not particularly limited, and examples thereof include propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-octene, 1-decene, and 1-dodecene. Among them, 1-hexene, 1-octene, and 1-decene are preferred.

[0080] <Polymerization process>

[0081] In the polymerization step, the monomers in the polymerization container are polymerized in the presence of hydrogen and a catalyst having a phosphinimido group.

[0082] The temperature during polymerization is not particularly limited. From the perspective of good yield of the cycloolefin copolymer, the temperature during polymerization is preferably 20°C or higher, more preferably 30°C or higher, further preferably 50°C or higher, further preferably 60°C or higher, and particularly preferably 70°C or higher. The temperature during polymerization may be 80°C or higher.

[0083] The upper limit of the temperature during polymerization is not particularly limited, and the upper limit of the temperature during polymerization may be, for example, 200° C. or lower, 140° C. or lower, or 120° C. or lower.

[0084] As the catalyst having a phosphinilide group, a metal-containing compound represented by the following formula (a1) is preferably used.

[0085] [Chemical formula 4]

[0086]

[0087] In the formula (a1), M is Ti, Zr or Hf, and Ti and Zr are particularly preferred from the viewpoints of easy availability, production of the metal-containing catalyst, and activity of the catalyst.

[0088] When M is Zr, from the viewpoint of improving the catalyst activity, it is preferred to add the catalyst to the polymerization system after the catalyst and the alkylaluminum compound are contacted in advance (after mixing).

[0089] As the alkylaluminum compound, for example, trimethylaluminum, triethylaluminum, triisobutylaluminum, MAO (usually containing an alkylaluminum) and the like are preferably used.

[0090] The amount of the alkylaluminum compound to be mixed with the catalyst is preferably 1 to 100 equivalents, more preferably 2 to 50 equivalents, and even more preferably 2 to 10 equivalents, based on the catalyst.

[0091] X is an organic substituent having 1 to 20 carbon atoms which may contain a hetero atom or a halogen atom.

[0092] L 1 is a group represented by the following formula (a1a) or formula (a1b). 2 is a group represented by the following formula (a1b). In formula (a1), L 1 and L 2 When both are groups represented by formula (a1b), L 1 and L 2 They may be the same group or different groups, but are preferably the same group.

[0093] [Chemical formula 5]

[0094]

[0095] In formula (a1a), R a1 ~R a5 Each independently represents a hydrogen atom which may be the same or different, or an organic substituent or an inorganic substituent having 1 to 20 carbon atoms which may contain a heteroatom. a1 ~R a5 Two adjacent groups on the 5-membered ring can combine with each other to form a ring.

[0096] In formula (a1b), R a6 ~Ra8 Each independently represents a hydrogen atom which may be the same or different, or an organic substituent or an inorganic substituent having 1 to 20 carbon atoms which may contain a heteroatom. a6 ~R a8 The two groups can combine with each other to form a ring.

[0097] In formula (a1), X is an organic substituent having 1 to 20 carbon atoms which may contain a hetero atom, or a halogen atom.

[0098] Regarding the organic substituent having 1 to 20 carbon atoms which may contain a heteroatom, when the organic substituent contains a heteroatom, the type of the heteroatom is not particularly limited within the scope of not hindering the effect of the manufacturing method of the present embodiment. Specific examples of the heteroatom include oxygen atoms, nitrogen atoms, sulfur atoms, phosphorus atoms, silicon atoms, selenium atoms, and halogen atoms.

[0099] The organic substituent is not particularly limited as long as it is a group that does not hinder the formation reaction of the metal-containing compound represented by the above formula (a1). For example, there can be mentioned an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aliphatic acyl group having 2 to 20 carbon atoms, a benzoyl group, an α-naphthylcarbonyl group, a β-naphthylcarbonyl group, an aromatic hydrocarbon group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, a trialkylsilyl group having 3 to 20 carbon atoms, a triarylsilyl group having 3 to 20 carbon atoms, a monosubstituted amino group substituted with a hydrocarbon group having 1 to 20 carbon atoms, and a disubstituted amino group substituted with a hydrocarbon group having 1 to 20 carbon atoms.

[0100] Among these organic substituents, preferred are an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, an aliphatic acyl group having 2 to 6 carbon atoms, a benzoyl group, a phenyl group, a benzyl group, a phenethyl group, a trialkylsilyl group having 3 to 10 carbon atoms, and a triarylsilyl group having 3 to 10 carbon atoms.

[0101] Among the organic substituents, more preferred are methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, adamantyl, methoxy, ethoxy, n-propyloxy, isopropyloxy, n-butyloxy, isobutyloxy, sec-butyloxy, tert-butyloxy, acetyl, propionyl, butyryl, phenyl, trimethylsilyl, triethylsilyl, tert-butyldimethylsilyl, triphenylsilyl and tripentafluorophenylsilyl.

[0102] X is preferably a halogen atom, more preferably a chlorine atom or a bromine atom, and particularly preferably a chlorine atom.

[0103] In formula (a1a), R a1 ~Ra5 Each independently represents a hydrogen atom which may be the same or different, an organic substituent having 1 to 20 carbon atoms which may contain a heteroatom, or an inorganic substituent. a1 ~R a5 Two adjacent groups on the 5-membered ring can combine with each other to form a ring.

[0104] As R a1 ~R a5 Specific examples and preferred examples of the organic substituent having 1 to 20 carbon atoms and optionally containing a hetero atom are the same as the specific examples and preferred examples of the organic substituent having 1 to 20 carbon atoms and optionally containing a hetero atom as X. a1 ~R a5 The organic substituent having 1 to 20 carbon atoms and may contain heteroatoms is -(CH 2 )nR represented by a substituent is preferred from the viewpoint of high catalyst activity and suppression of polyethylene-like impurities. Moreover, it is particularly preferred that only R a1 ~R a5 One is by -(CH 2 )nR represents a substituent, and the other four are hydrogen atoms. 2 )nR, R represents one or more selected from the group consisting of a hydrogen atom, an alkyl group, a cycloalkyl group, a halogenated alkyl group, an aryl group, a halogenated aryl group, an alkylsilyl group and an arylsilyl group, and n represents an integer of 1 to 5.

[0105] Examples of the alkyl group for R include alkyl groups having 1 to 5 carbon atoms, and preferably alkyl groups having 1 to 4 carbon atoms. Specific examples of the alkyl group for R include methyl, ethyl, isopropyl, n-butyl, tert-butyl, etc., and tert-butyl is preferred.

[0106] Examples of the cycloalkyl group for R include cycloalkyl groups having 3 to 20 carbon atoms, preferably cycloalkyl groups having 3 to 10 carbon atoms, and more preferably cycloalkyl groups having 5 to 8 carbon atoms. Specific examples of the cycloalkyl group for R include cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl, among which cyclohexyl is preferred.

[0107] The haloalkyl group as R is an alkyl group having at least one halogen element as a substituent, and examples thereof include alkyl groups having 1 to 7 carbon atoms, preferably alkyl groups having 1 to 5 carbon atoms, and more preferably haloalkyl groups having 1 to 3 carbon atoms. In addition, the halogen element in the haloalkyl group as R is preferably fluorine or chlorine. Specific examples of the haloalkyl group as R include monofluoromethyl, difluoromethyl, trifluoromethyl, 2,2,2-trifluoroethyl, pentafluoroethyl, heptafluoropropyl, trichloromethyl, etc., among which trifluoromethyl is preferred.

[0108] Examples of the aryl group for R include aryl groups having 6 to 20 carbon atoms, preferably aryl groups having 6 to 10 carbon atoms, and more preferably aryl groups having 7 to 8 carbon atoms.

[0109] Specific examples of the aryl group of R include phenyl, tolyl, xylyl, mesityl, naphthyl, aralkyl, biphenyl and the like, and among them, phenyl is preferred.

[0110] The halogenated aryl group as R is an aryl group having at least one halogen element as a substituent on the above-mentioned aryl group as R, and examples thereof include aryl groups having 6 to 20 carbon atoms, preferably aryl groups having 6 to 10 carbon atoms, and more preferably aryl groups having 7 to 8 carbon atoms. In addition, the halogen element in the halogenated aryl group as R is preferably fluorine or chlorine. Specific examples of the halogenated aryl group as R include 4-fluorophenyl, 2,4-difluorophenyl, 2,4,6-trifluorophenyl, 2,3,6-trifluorophenyl, perfluorophenyl (-C 6 F 5 ), perfluorobiphenyl, perchlorophenyl (-C 6 Cl 5 ), etc., among which perfluorophenyl (-C 6 F 5 ).

[0111] Examples of the alkylsilyl group for R include trialkylsilyl groups such as trimethylsilyl and triethylsilyl, and among them, trimethylsilyl is preferred.

[0112] Examples of the arylsilyl group for R include triarylsilyl groups such as triphenylsilyl and tripentafluorophenylsilyl. Among them, triphenylsilyl is preferred.

[0113] Among these R, a hydrogen atom, a group having a large number of carbon atoms (carbon number: 3 to 12) in an alkyl group, or a group containing a fluorine atom is preferred. For example, a hydrogen atom, a tert-butyl group, a phenyl group, a perfluorophenyl group (-C 6 F 5 ), trimethylsilyl.

[0114] -(CH 2 )nR, n represents an integer of 1-5, preferably 1-3.

[0115] The inorganic substituent is not particularly limited as long as it is a group that does not inhibit the production reaction of the metal-containing compound represented by the above formula (a1).

[0116] Specific examples of the inorganic substituent include a halogen atom, a nitro group, an unsubstituted amino group, and a cyano group.

[0117] In formula (a1b), R a6 ~Ra8 Each independently represents a hydrogen atom which may be the same or different, an organic substituent having 1 to 20 carbon atoms which may contain a heteroatom, or an inorganic substituent. a6 ~R a8 The two groups can combine with each other to form a ring.

[0118] As R a6 ~R a8 Specific examples and preferred examples of the organic substituent having 1 to 20 carbon atoms and optionally containing a hetero atom are the same as the specific examples and preferred examples of the organic substituent having 1 to 20 carbon atoms and optionally containing a hetero atom as X. a6 ~R a8 The organic substituent having 1 to 20 carbon atoms which may contain a hetero atom may include adamantyl and o-tolyl as preferred examples.

[0119] In addition, as R a6 ~R a8 The organic substituent having 1 to 20 carbon atoms and optionally containing a hetero atom is preferably a group represented by formula (a1b), that is, R a6 ~R a8 Each of which is independently a hydrocarbon group having 1 to 20 carbon atoms.

[0120] As R a6 ~R a8 Preferred examples of the case where the organic substituent having 1 to 20 carbon atoms and optionally containing a hetero atom is a group represented by the formula (a1b) include -N=P(Me) 3 、-N=P(Et) 3 、-N=P(n-Pr) 3 、-N=P(iso-Pr) 3 、-N=P(n-Bu) 3 、-N=P(iso-Bu) 3 、-N=P(sec-Bu) 3 、-N=P(tert-Bu) 3 、-N=P(-N=P(tert-Bu) 3 )Ph 2 and -N=P(Ph) 3 Among them, -N=P(tert-Bu) is preferred. 3 and -N=P(iso-Pr) 3 , more preferably -N=P(tert-Bu) 3In addition, Me is a methyl group, Et is an ethyl group, n-Pr is a n-propyl group, iso-Pr is an isopropyl group, n-Bu is a n-butyl group, iso-Bu is an isobutyl group, sec-Bu is a sec-butyl group, tert-Bu is a tert-butyl group, and Ph is a phenyl group.

[0121] In addition, as R a6 ~R a8 Specific examples of inorganic substituents are as follows: a1 ~R a5 The specific examples of the inorganic substituent are the same as those of the above.

[0122] As R a6 ~R a8 , preferably, a cyclic or non-cyclic tertiary alkyl group, or an aromatic ring group having at least one alkyl group at the ortho position. Examples of the cyclic tertiary alkyl group include adamantyl, and examples of the non-cyclic tertiary alkyl group include tert-butyl. Examples of the aromatic ring group having at least one alkyl group at the ortho position include o-tolyl, mesityl, and the like.

[0123] Preferred examples of the group represented by the formula (a1b) include -N=P(Me) 3 、-N=P(Et) 3 、-N=P(n-Pr) 3 、-N=P(iso-Pr) 3 、-N=P(n-Bu) 3 、-N=P(iso-Bu) 3 、-N=P(sec-Bu) 3 、-N=P(tert-Bu) 3 、-N=P(Ph) 3 、-N=P(-N=P(tert-Bu) 3 )Ph 2 and -N=P(-N=P(iso-Pr) 3 )Ph 2 Among them, -N=P(tert-Bu) is preferred 3 and -N=P(iso-Pr) 3 , more preferably -N=P(tert-Bu) 3 .

[0124] Preferred specific examples of the metal-containing compound represented by the above-described formula (a1) include the following metal-containing compounds: In the following formula, M is the same as M in the formula (a1).

[0125] In addition, in the following formula, Si(Me) 3 is trimethylsilyl, Si(Me) 2Tert-butyl is tert-butyldimethylsilyl.

[0126] [Chemical formula 6]

[0127]

[0128] [Chemical formula 7]

[0129]

[0130] [Chemical formula 8]

[0131]

[0132] The polymerization of the monomer is preferably carried out in the presence of the above-mentioned catalyst having a phosphinimide group and a co-catalyst. As the co-catalyst, a compound commonly used as a co-catalyst in the polymerization of olefins can be used without particular limitation. Preferred examples of the co-catalyst include aluminoxane and an ionic compound. From the aspect that the polymerization reaction is easy to proceed smoothly, it is particularly preferred to use at least one of aluminoxane and a borate compound as an ionic compound as a co-catalyst for the polymerization of the monomer.

[0133] Therefore, the above-mentioned catalyst having a phosphinilide group is preferably mixed with aluminoxane and / or an ionic compound to form a catalyst composition.

[0134] Here, the ionic compound is a compound that generates a cationic transition metal compound by reacting with a catalyst having a phosphinimido group.

[0135] The catalyst composition is preferably prepared using a solution of a catalyst having a phosphinimido group. The solvent contained in the catalyst solution having a phosphinimido group is not particularly limited. Preferred solvents include hydrocarbon solvents such as pentane, hexane, heptane, octane, isooctane, isododecane, mineral oil, cyclohexane, methylcyclohexane, decalin (decahydronaphthalene), mineral oil, benzene, toluene and xylene, and halogenated hydrocarbon solvents such as chloroform, methylene chloride, dichloromethane, ethylene dichloride and chlorobenzene.

[0136] The amount of the solvent used is not particularly limited as long as it can produce a catalyst composition with the desired performance. Typically, the concentration of the catalyst having a phosphinimido group, aluminoxane and ionic compound can be preferably 0.00000001 to 100 mol / L, more preferably 0.00000005 to 50 mol / L, and particularly preferably 0.0000001 to 20 mol / L.

[0137] When the liquid containing the raw material of the catalyst composition is mixed, it is preferred that the number of moles of the transition metal element in the catalyst having a phosphinimidyl group is M a The number of moles of aluminum in aluminoxane is M b1 The number of moles of the ionic compound is M b2 In the case of (M b1 +M b2 The liquid containing the raw material of the catalyst composition is mixed so that the value of ) / Ma is preferably 1 to 200,000, more preferably 5 to 100,000, and particularly preferably 10 to 80,000.

[0138] The temperature of the liquid in which the raw materials containing the catalyst composition are mixed is not particularly limited, but is preferably -100 to 100°C, more preferably -50 to 50°C.

[0139] The solution of the catalyst having a phosphinilide group and the aluminoxane and / or the ionic compound for preparing the catalyst composition may be mixed in a device different from the polymerization vessel before polymerization or in the polymerization vessel before or during polymerization.

[0140] Hereinafter, the materials used in the preparation of the catalyst composition and the preparation conditions of the catalyst composition will be described.

[0141] [Aluminoxane]

[0142] As the aluminoxane, various aluminoxanes that have been used as co-catalysts in polymerization of various olefins can be used without particular limitation. Typically, the aluminoxane is an organoaluminoxane.

[0143] When the catalyst composition is produced, the aluminoxane may be used alone or in combination of two or more.

[0144] As the aluminoxane, alkylaluminoxane is preferably used. As the alkylaluminoxane, for example, a compound represented by the following formula (b1-1) or (b1-2) can be cited. The alkylaluminoxane represented by the following formula (b1-1) or (b1-2) is a product obtained by the reaction of trialkylaluminum and water.

[0145] [Chemical formula 9]

[0146]

[0147] [In formula (b1-1) and formula (b1-2), R represents an alkyl group having 1 to 4 carbon atoms, and n represents an integer of 0 to 40, preferably 2 to 30.]

[0148] Examples of the alkylaluminoxane include methylaluminoxane and modified methylaluminoxane (MMAO) in which a part of the methyl group of methylaluminoxane is substituted with other alkyl groups. As the modified methylaluminoxane, for example, as the substituted alkyl group, preferably a modified methylaluminoxane having an alkyl group with 2 to 4 carbon atoms such as ethyl, propyl, isopropyl, butyl, isobutyl, etc. is used, and more preferably a modified methylaluminoxane in which a part of the methyl group is substituted with an isobutyl group is used. Specific examples of the alkylaluminoxane include methylaluminoxane, ethylaluminoxane, propylaluminoxane, butylaluminoxane, isobutylaluminoxane, methylethylaluminoxane, methylbutylaluminoxane, methylisobutylaluminoxane, etc., among which methylaluminoxane and methylisobutylaluminoxane are preferred.

[0149] Alkyl aluminoxane can be prepared by a known method. In addition, commercially available products can be used as alkyl aluminoxane. Commercially available products of alkyl aluminoxane include, for example, MMAO-3A, ​​TMAO-200 series, TMAO-340 series, solid MAO (all manufactured by Tosoh Finechem Co., Ltd.), methyl aluminoxane solution (manufactured by Albemarle Corporation), and the like.

[0150] [Ionic compounds]

[0151] The ionic compound is a compound that generates a cationic transition metal compound by reacting with a catalyst having a phosphinimido group.

[0152] As the ionic compounds involved, anions containing tetrakis(pentafluorophenyl)borate, dimethylphenylammonium cations ((CH 3 ) 2 N(C 6 H 5 )H + ) such as an amine cation having an active proton, (C 6 H 5 ) 3 C + Ionic compounds of ions such as such trisubstituted carbocations, carborane cations, metal carborane cations, and ferrocenium cations having transition metals.

[0153] Preferred examples of ionic compounds include borates. Preferred specific examples of borates include tetrakis(pentafluorophenyl)trityl borate, dimethylphenylammonium tetrakis(pentafluorophenyl)borate, and N-methyldialkylammonium tetrakis(pentafluorophenyl)borate, such as N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate and N-methyldi-n-decylammonium tetrakis(pentafluorophenyl)borate.

[0154] Furthermore, from the viewpoint of easily producing the cycloolefin copolymer in good yield, it is preferred that one or more selected from aluminoxanes and alkylaluminum compounds be present in the polymerization vessel before adding the catalyst having a phosphiniide group or the catalyst composition containing the catalyst having a phosphiniide group.

[0155] The aluminoxane is as described in the method for producing the catalyst composition.

[0156] As the alkylaluminum compound, any compound conventionally used in polymerization of olefins etc. can be used without particular limitation. Examples of the alkylaluminum compound include compounds represented by the following general formula (II).

[0157] (R 10 ) z AlX 3-z (II)

[0158] (In the general formula (II), R 10 is an alkyl group having 1 to 15 carbon atoms, preferably 1 to 8 carbon atoms, X is a halogen atom or a hydrogen atom, and z is an integer of 1 to 3.

[0159] Examples of the alkyl group having 1 to 15 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, and n-octyl group.

[0160] Specific examples of the alkylaluminum compound include trialkylaluminum such as trimethylaluminum, triethylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-sec-butylaluminum, and tri-n-octylaluminum; dialkylaluminum halides such as dimethylaluminum chloride and diisobutylaluminum chloride; dialkylaluminum hydrides such as diisobutylaluminum hydride; and dialkylaluminum alkoxides such as dimethylaluminum methoxide.

[0161] When aluminoxane is added to the polymerization vessel before adding the catalyst having a phosphiniide group or the catalyst composition containing the catalyst having a phosphiniide group, the amount thereof is preferably 1 to 1,000,000 mol, more preferably 10 to 100,000 mol, as the number of moles of aluminum in the aluminoxane relative to 1 mol of the catalyst having a phosphiniide group.

[0162] When the alkyl aluminum compound is added to the polymerization vessel before adding the catalyst having a phosphiniide group or the catalyst composition containing the catalyst having a phosphiniide group, the amount thereof is preferably 1 to 500,000 mol, more preferably 10 to 50,000 mol, as the number of moles of aluminum per 1 mol of the catalyst having a phosphiniide group.

[0163] The polymerization is preferably carried out in the presence of a catalyst having a phosphiniide group and aluminoxane or in the presence of a catalyst having a phosphiniide group, an ionic compound and an alkylaluminum.

[0164] The polymerization conditions are not particularly limited as long as a cycloolefin copolymer having desired physical properties can be obtained, and known conditions can be used.

[0165] The amount of the catalyst composition can be deduced from the amount of the compound having a phosphinimido group used in its preparation. The amount of the catalyst composition, as the mass of the compound having a phosphinimido group used in its preparation, is preferably 0.000000001 to 0.005 mol, more preferably 0.00000001 to 0.0005 mol, relative to 1 mol of the norbornene monomer.

[0166] The polymerization time is not particularly limited, and the polymerization is carried out until a desired yield is achieved or the molecular weight of the polymer increases to a desired level.

[0167] The polymerization time varies depending on the temperature, the composition of the catalyst, and the composition of the monomers, but is typically 0.01 to 120 hours, preferably 0.1 to 80 hours, and more preferably 0.2 to 10 hours.

[0168] Preferably, at least a portion, preferably all, of the catalyst composition is added continuously to the polymerization vessel.

[0169] By continuously adding the catalyst composition, the cycloolefin copolymer can be produced continuously, and the production cost of the cycloolefin copolymer can be reduced.

[0170] According to the method described above, whenever a cycloolefin copolymer is obtained by copolymerizing a monomer containing a norbornene monomer and ethylene, a decrease in yield can be suppressed and the molecular weight of the produced cycloolefin copolymer can be controlled.

[0171] The glass transition temperature of the obtained cycloolefin copolymer is not particularly limited, but is, for example, preferably 185°C or lower, more preferably 160°C or lower, further preferably 130°C or lower, further preferably 120°C or lower, and particularly preferably 100°C or lower.

[0172] In addition, it is also preferred that, in accordance with the method described in JIS K7121, under a nitrogen atmosphere, under the condition of a heating rate of 20°C / min, the cycloolefin copolymer manufactured by the above method is measured using a differential operating calorimeter (DSC), and the obtained DSC curve does not have a peak of the melting point (melting enthalpy) derived from the polyethylene-like impurities. This means that there are no polyethylene-like impurities in the cycloolefin copolymer or there are very few. In addition, when the cycloolefin copolymer contains polyethylene-like impurities, the peak of the melting point derived from the polyethylene-like impurities on the DSC curve is usually detected in the range of 100°C to 140°C.

[0173] The cycloolefin copolymer produced by the above method has a low content of polyethylene-like impurities and excellent transparency. Therefore, the cycloolefin copolymer produced by the above method is particularly preferably used in materials requiring high transparency, such as optical films or optical sheets, films or sheets for packaging materials, etc., from the perspective of optical function and aesthetics.

[0174] Example

[0175] Hereinafter, the present embodiment will be described in more detail by way of examples, but the present embodiment is not limited to the following examples.

[0176] [Example 1]

[0177] Into a dried 1000 mL stainless steel autoclave equipped with a MAXBLEND stirring blade, decalin (decahydronaphthalene) and the amount (37 to 52 mmol) of 2-norbornene listed in Table 1 were added. Next, 50 μmol of triisobutylaluminum (manufactured by Tosoh Fine Chemicals Co., Ltd.) was added, and the autoclave was heated to 90°C. After introducing 0.001 MPa of hydrogen into the autoclave, an ethylene pressure of 0.8 MPa was applied, and a solution of N-methyldialkylammonium tetrakis(pentafluorophenyl)borate (alkyl group: C14-C18 (average: C17.5) (manufactured by Tosoh Fine Chemicals Co., Ltd.) prepared using decahydronaphthalene was added in an amount of 0.3 μmol of N-methyldialkylammonium tetrakis(pentafluorophenyl)borate. Next, a catalyst solution of catalyst 1 represented by the following structural formula prepared using toluene was added in an amount of 0.1 μmol, and 30 seconds later was taken as the polymerization start time point. In addition, the total amount of the polymerization solution was 500 mL. After 15 minutes from the start of the polymerization, the supply of ethylene was stopped, and after the pressure was carefully returned to normal pressure, isopropyl alcohol (isopropyl The reaction was stopped by adding 1500 mL of acetone, 1000 mL of isopropanol and 25 mL of hydrochloric acid to the polymerization solution to precipitate the copolymer. The copolymer was recovered by suction, washed with acetone and methanol, and then vacuum dried at 110° C. for 12 hours to obtain a copolymer of norbornene and ethylene.

[0178] [Chemical formula 10]

[0179]

[0180] [Example 2]

[0181] A cycloolefin copolymer was obtained in the same manner as in Example 1 except that hydrogen was introduced into the autoclave to a pressure of 0.003 MPa.

[0182] [Example 3]

[0183] A cycloolefin copolymer was obtained in the same manner as in Example 2 except that the catalyst 1 was changed to the catalyst 2 represented by the following structural formula.

[0184] [Chemical formula 11]

[0185]

[0186] [Example 4]

[0187] A cycloolefin copolymer was obtained in the same manner as in Example 2 except that the catalyst 1 was changed to the catalyst 3 represented by the following structural formula.

[0188] [Chemical formula 12]

[0189]

[0190] [Example 5]

[0191] A cycloolefin copolymer was obtained in the same manner as in Example 2 except that the catalyst 1 was changed to the catalyst 4 represented by the following structural formula.

[0192] [Chemical formula 13]

[0193]

[0194] [Example 6]

[0195] The cycloolefin copolymer was obtained in the same manner as in Example 2 except that the catalyst 1 was changed to the catalyst 5 represented by the following structural formula and the catalyst solution of the catalyst 5 was added in the following manner. That is, the method of adding the catalyst solution was different from that in Example 2 (Example 1), and the description "Next, the catalyst solution of the catalyst 1 represented by the following structural formula prepared using toluene was added in such a way that the catalyst amount became 0.1 μmol, and 30 seconds later was regarded as the polymerization start time point." in Example 1 was replaced with "Next, the toluene solution of trimethylaluminum was slowly dripped into the catalyst solution of the catalyst 5 represented by the following structural formula prepared using toluene, so that the added amount of trimethylaluminum became 6.7 equivalents relative to the catalyst amount, and then stirred at room temperature for 1 hour, and then it was added in such a way that the catalyst amount became 0.1 μmol, and 30 seconds later was regarded as the polymerization start time point.".

[0196] [Chemical formula 14]

[0197]

[0198] [Example 7]

[0199] A cycloolefin copolymer was obtained in the same manner as in Example 2 except that Catalyst 1 was changed to Catalyst 5 represented by the above structural formula and the catalyst solution of Catalyst 5 was added in the following manner. That is, the method of adding the catalyst solution was different from that in Example 2 (Example 1), and the description "Next, a catalyst solution of Catalyst 1 represented by the following structural formula prepared using toluene was added in such a manner that the catalyst amount became 0.1 μmol, and 30 seconds later was taken as the polymerization start time point." in Example 1 was replaced with "Next, a TMAO-211 toluene solution (a solution of 9.0 mass % (content as Al atoms) of methylaluminoxane, manufactured by Tosoh Fine Chemicals Co., Ltd., and containing 26 mol % of trimethylaluminum relative to the total Al) was slowly added dropwise to the catalyst solution of Catalyst 5 represented by the following structural formula prepared using toluene, and the amount of trimethylaluminum added became 6.7 equivalents relative to the catalyst amount, and the mixture was stirred at room temperature for 1 hour, and the catalyst solution was added in such a manner that the catalyst amount became 0.1 μmol, and 30 seconds later was taken as the polymerization start time point.".

[0200] [Example 8]

[0201] The cycloolefin copolymer was obtained in the same manner as in Example 2 except that the catalyst 1 was changed to the catalyst 6 represented by the following structural formula and the catalyst solution of the catalyst 6 was added in the following manner. That is, the method of adding the catalyst solution was different from that in Example 2 (Example 1), and the description "Next, the catalyst solution of the catalyst 1 represented by the following structural formula prepared using toluene was added in such a way that the catalyst amount became 0.1 μmol, and 30 seconds later was regarded as the polymerization start time point." in Example 1 was replaced with "Next, the toluene solution of trimethylaluminum was slowly dripped into the catalyst solution of the catalyst 6 represented by the following structural formula prepared using toluene, so that the added amount of trimethylaluminum became 6.7 equivalents relative to the catalyst amount, and then stirred at room temperature for 1 hour, and then it was added in such a way that the catalyst amount became 0.1 μmol, and 30 seconds later was regarded as the polymerization start time point.".

[0202] [Chemical formula 15]

[0203]

[0204] [Comparative Examples 1-2]

[0205] In Comparative Examples 1 and 2, cycloolefin copolymers were obtained in the same manner as in Example 1 or Example 2, except that hydrogen was not introduced before ethylene pressure was applied in the autoclave.

[0206] [Comparative Example 3]

[0207] A cycloolefin copolymer was obtained in the same manner as in Comparative Example 2 except that diisobutylaluminum hydride (manufactured by Tokyo Chemical Industry Co., Ltd., 17 wt % toluene solution) was used as the organic metal compound.

[0208] [Comparative Examples 4 to 7]

[0209] In Comparative Examples 4 to 7, cycloolefin copolymers were obtained in the same manner as in Examples 4, 5, 7 and 8, except that hydrogen was not introduced before ethylene pressure was applied to the autoclave.

[0210] [evaluate]

[0211] The following evaluations and measurements were performed on the cycloolefin copolymers obtained in the respective Examples and Comparative Examples.

[0212] (1) Molecular weight determination

[0213] The number average molecular weight (Mn) and the weight average molecular weight (Mw) of the cycloolefin copolymer obtained in each of Examples and Comparative Examples were measured by gel permeation chromatography under the following measurement conditions.

[0214] Device: Viscotek TDA302 detector + Pump autosampler made by Malvern

[0215] Detector: RI

[0216] Solvent: Toluene

[0217] Chromatographic column: TSKgel GMHHR-M manufactured by Tosoh Corporation

[0218] Flow rate: 1mL / min

[0219] Temperature: 75℃

[0220] Sample concentration: 2.5 mg / mL

[0221] Injection volume: 100 μL

[0222] Standard sample: Monodisperse polystyrene

[0223] (2) Production of cycloolefin copolymers

[0224] In each of the Examples and Comparative Examples, the copolymer yield (g) per 1 g of the catalyst was calculated from the amount of the catalyst used and the copolymer yield. The calculation results are shown in Tables 1 and 2.

[0225] (3) Determination of glass transition temperature (Tg)

[0226] The glass transition temperature of the cycloolefin copolymer obtained in each example and comparative example was measured by the DSC method (method described in JIS K7121) using a differential scanning calorimeter (differential scanning calorimeter (DSC-Q1000) manufactured by TA Instrument Co., Ltd.) under a nitrogen atmosphere at a heating rate of 20°C / min. The measurement results are shown in Tables 1 and 2.

[0227] (4) Impurity thermal analysis

[0228] In the DSC curve obtained by measuring the glass transition temperature, the calorific value (mJ / mg) is calculated based on the peak area of ​​the melting point of the polyethylene-like impurities observed in the range of 100 to 140°C. The larger the calculated calorific value, the greater the content of the polyethylene-like impurities. In addition, "not detected" in Tables 1 to 2 means that the peak of the melting point of the polyethylene-like impurities is not detected on the DSC curve.

[0229] (5) Turbidity test

[0230] After dissolving 0.1 g of the cycloolefin copolymer obtained in each example and comparative example in 10 g of toluene, the solution was observed for turbidity. The case where no turbidity was confirmed was evaluated as "good", and the case where turbidity was confirmed was evaluated as "poor". The evaluation results are shown in Tables 1 to 2. When turbidity was confirmed, the cycloolefin copolymer contained polyethylene-like impurities. When turbidity was not confirmed, the cycloolefin copolymer did not contain polyethylene-like impurities.

[0231] [Table 1]

[0232]

[0233] [Table 2]

[0234]

[0235] As can be seen from Tables 1 and 2, the molecular weight of the obtained cycloolefin copolymer changes depending on the concentration (hydrogen pressure) of hydrogen charged into the polymerization vessel, according to the comparison of Example 1, Example 2 with Comparative Example 1, Example 3 with Comparative Example 2, Example 4 with Comparative Example 4, Example 5 with Comparative Example 5, Example 7 with Comparative Example 6, and Example 8 with Comparative Example 7, which are almost the same except for the hydrogen pressure. Specifically, it can be seen that the molecular weight decreases when the hydrogen concentration is increased (the pressure is increased).

[0236] On the other hand, as described above, when M in the metal-containing compound represented by the above formula (a1) as a catalyst having a phosphinimide group is Zr, it is preferred to add the catalyst to the polymerization system after the catalyst is pre-contacted with the alkylaluminum compound (after mixing) from the viewpoint of improving the catalyst activity. Moreover, Examples 6 to 8 use compounds in which M in the metal-containing compound represented by the above formula (a1) is Zr. In Example 6, Catalyst 5 is pre-contacted with trimethylaluminum before being added to the polymerization system. In addition, in Examples 7 and 8, Catalyst 5 or Catalyst 6 is pre-contacted with a TMAO-211 toluene solution containing trimethylaluminum before being added to the polymerization system. In all of Examples 6 to 8, the amount of trimethylaluminum added is 6.7 equivalents relative to the amount of the catalyst. As a result, it can be seen that since the yield per 1g of the catalyst is also good in Examples 6 to 8, the alkylaluminum originally contained in TMAO-211 is also effective for the compound in which M in the metal-containing compound represented by the above formula (a1) is Zr.

[0237] In Examples 1 to 8, no impurities were detected by impurity thermal analysis, and the polymer solution did not show turbidity in the turbidity test, indicating that the generation of polyethylene-like impurities was suppressed. In addition, the yield per 1 g of catalyst was also good in Examples 1 to 8. On the other hand, it is believed that in Comparative Example 3, an undesirable side reaction was carried out due to the organometallic compound, and polyethylene-like impurities were generated.

Claims

1. A method for producing a cyclic olefin copolymer, wherein the cyclic olefin copolymer comprises a structural unit derived from a norbornene monomer and a structural unit derived from ethylene, characterized in that: The method for producing the cycloolefin copolymer comprises: a charging step of charging at least monomers containing norbornene monomer and ethylene and hydrogen into a polymerization container; and a polymerization step of polymerizing the monomer in the polymerization container in the presence of the hydrogen gas and a catalyst having a phosphinimide group, The catalyst having the phosphinimide group is a metal-containing compound represented by the following formula (a1), [Chemical formula 1] In formula (a1), M is Ti, Zr or Hf, X is an organic substituent having 1 to 20 carbon atoms which may contain a hetero atom or a halogen atom, and L is 1 is a group represented by the following formula (a1a), L 2 is a group represented by the following formula (a1b), [Chemical formula 2] In formula (a1a), R a1 ~R a5 Each independently represents a hydrogen atom which may be the same or different, an organic substituent having 1 to 20 carbon atoms which may contain a heteroatom, or an inorganic substituent, and in R a1 ~R a5 The two adjacent groups on the 5-membered ring can combine with each other to form a ring. In formula (a1b), R a6 ~R a8 Each independently represents a hydrogen atom which may be the same or different, an organic substituent having 1 to 20 carbon atoms which may contain a heteroatom, or an inorganic substituent selected from R a6 ~R a8 The two groups can combine to form a ring. The molecular weight of the cycloolefin copolymer produced in the polymerization step is controlled by adjusting the concentration of the hydrogen gas charged into the polymerization container.

2. The method for producing a cycloolefin copolymer according to claim 1, characterized in that: Based on the molecular weight of the cycloolefin copolymer obtained in one polymerization step, the concentration of hydrogen charged into the polymerization vessel is set according to the following condition (A) or the following condition (B) in the next charging step. Condition (A): When the molecular weight of the cycloolefin copolymer produced in the polymerization step is greater than the desired molecular weight, the concentration of hydrogen charged into the polymerization vessel is increased in the next charging step, Condition (B): When the molecular weight of the cycloolefin copolymer produced in the polymerization step is lower than a desired molecular weight, the concentration of hydrogen charged into the polymerization container is reduced in the next charging step.

3. The method for producing a cycloolefin copolymer according to claim 1 or 2, characterized in that: In the above formula (a1), M is Ti.

4. The method for producing a cycloolefin copolymer according to claim 1 or 2, characterized in that: The polymerization of the monomer is carried out in the presence of the catalyst having the phosphinimide group and a co-catalyst.

5. The method for producing a cycloolefin copolymer according to claim 4, characterized in that: The co-catalyst contains at least one of aluminoxane and a borate compound.

6. The method for producing a cycloolefin copolymer according to claim 1 or 2, characterized in that: The polymerization of the monomers is carried out in the presence of a hydrocarbon solvent.

7. The method for producing a cycloolefin copolymer according to claim 1 or 2, characterized in that: The cycloolefin copolymer sample was measured by differential scanning calorimetry under a nitrogen atmosphere at a heating rate of 20°C / min according to the method described in JIS K7121. The obtained DSC curve had no melting point peak derived from polyethylene-like impurities in the range of 100°C to 140°C.

8. The method for producing a cycloolefin copolymer according to claim 1 or 2, characterized in that: The molecular weight distribution (Mw / Mn) of the cycloolefin copolymer is 3.0 or less.

Images