JP5820756B2 - Process for producing aromatic vinyl compound polymer - Google Patents

Description

  The present invention relates to a method for producing an aromatic vinyl compound polymer having a syndiotactic structure having a high syndiotacticity, and more specifically, using a powder bed continuous polymerization apparatus in the presence of a group 3 transition metal complex. The present invention relates to a method for producing an aromatic vinyl compound polymer having a tic structure.

  In recent years, olefin polymers are important as molding materials and the like, and many technical developments have been made on the polymers and their production methods. For example, regarding the production method, technical development has been conducted on solid catalysts such as Ziegler-Natta catalysts and catalysts using metal complexes, and the results have been reported. In particular, catalysts that use metal complexes have been found to have high homogeneity, and that the reactivity can be changed by changing the central metal or ligand of the metal complex. Has been continued.

Examples of the metal complex include a metallocene complex, and so far, a metal complex having two cyclic ligands such as a cyclopentadienyl group and an indenyl group, and a metal including a bridging group that binds the cyclic ligand. Complexes (crosslinked metallocene complexes), metal complexes having one cyclic ligand (half metallocene complex), and the like have been reported (hereinafter, a catalyst using a metallocene complex may be abbreviated as “metallocene catalyst”). ).
In a metallocene catalyst, the positional relationship between a monomer and a growing polymer chain during polymerization can be controlled by selecting a cyclic ligand, introducing a substituent, and the like. A polymer having properties (isotacticity, syndiotacticity, etc.) can be produced.
As for the central metal in the metallocene complex, group 4 transition metals such as titanium, zirconium and hafnium were conventionally used, but in recent years, group 3 transition metals such as scandium, yttrium and lanthanum and lanthanoid metals are used. A polymerization reaction using a half metallocene complex has been reported.

By the way, an aromatic vinyl compound polymer having a syndiotactic structure (hereinafter sometimes abbreviated as “syndiotactic polymer”) is characterized by excellent mechanical strength, heat resistance, appearance, solvent resistance, and the like. Are used in various applications.
Regarding the catalyst for producing a syndiotactic polymer, there is a report on a metallocene catalyst using a metal other than the Group 4 transition metal. For example, Patent Document 1 contains a Group 3 metal atom or a lanthanoid metal atom. A polymerization catalyst composition containing a half metallocene complex and a polymer having high syndiotacticity obtained using the same are disclosed.

International Publication No. 2006/004068

  By the way, when a half titanocene catalyst is used, a syndiotactic polymer having a narrow molecular weight distribution can be produced regardless of the polymerization mode. However, in the case of a metallocene catalyst containing a group 3 transition metal atom as described above, a polymer having a narrow molecular weight distribution can be obtained by solution polymerization or bulk polymerization using a batch polymerization apparatus. When a powder bed continuous polymerization apparatus suitable for the production of is used, there is a problem that the molecular weight distribution becomes wide. When the molecular weight distribution is wide, when a polymer having a predetermined weight average molecular weight or a predetermined intrinsic viscosity is produced, the proportion of low molecular weight substances is increased, and the physical properties of the polymer are deteriorated.

  The problem to be solved by the present invention is a method for producing an aromatic vinyl compound polymer having a syndiotactic structure with a narrow molecular weight distribution in the presence of a group 3 transition metal complex using a powder bed continuous polymerization apparatus. It is to provide.

  As a result of intensive studies, the present inventors have added hydrogen to the reaction system when polymerizing an aromatic vinyl monomer in the presence of a group 3 transition metal complex using a powder bed continuous polymerization apparatus. Thus, it has been found that an aromatic vinyl compound polymer having a syndiotactic structure with a narrow molecular weight distribution can be efficiently produced. The present invention has been completed based on such knowledge.

That is, this invention provides the manufacturing method of the following aromatic vinyl compound polymers.
[1] A method for producing an aromatic vinyl compound polymer having a syndiotactic structure using a powder bed continuous polymerization apparatus, comprising (A) a group 3 transition metal complex and (B) a catalyst composition And (C) hydrogen is added to the reaction system when the aromatic vinyl compound polymer is produced by polymerizing the aromatic vinyl monomer in the presence of the above.
[2] The method for producing an aromatic vinyl compound polymer according to the above [1], wherein the molecular weight distribution of the obtained aromatic vinyl compound polymer is 3 or less.
[3] The method for producing an aromatic vinyl compound polymer according to the above [1] or [2], wherein the aromatic vinyl monomer is styrene.
[4] The method for producing an aromatic vinyl compound polymer according to any one of [1] to [3], wherein the group 3 transition metal complex is represented by the following general formula (I).
RMX _a-1 Y _b (I)
[Wherein, R represents a cyclopentadienyl-based π ligand, M represents a group 3 or lanthanoid series transition metal in the periodic table, X represents a monoanionic ligand, and Y represents a Lewis base. Show. a represents the valence of M, and b represents 0, 1 or 2. ]
[5] The method for producing an aromatic vinyl compound polymer according to the above [4], wherein the group 3 transition metal complex is a scandium complex.
[6] The aromatic vinyl compound according to any one of [1] to [5], wherein the promoter is (B-1) a non-coordinating ionic compound or (B-2) an organoaluminum oxy compound. A method for producing a polymer.
[7] The method for producing an aromatic vinyl compound polymer according to the above [6], wherein the non-coordinating ionic compound is an ionic compound comprising a non-coordinating anion and a cation.
[8] The method for producing an aromatic vinyl compound polymer according to any one of [1] to [7], wherein the catalyst composition further contains (D) an organoaluminum compound.

  According to the method of the present invention, an aromatic vinyl compound polymer having a syndiotactic structure with a narrow molecular weight distribution is efficiently produced in the presence of a group 3 transition metal complex using a powder bed continuous polymerization apparatus. Can do.

  The method for producing an aromatic vinyl compound polymer of the present invention is a method for producing an aromatic vinyl compound polymer having a syndiotactic structure using a powder bed continuous polymerization apparatus, and comprises (A) a group 3 transition metal complex And (B) (C) adding hydrogen to the reaction system when producing the aromatic vinyl compound polymer by polymerizing an aromatic vinyl monomer in the presence of a catalyst composition containing a cocatalyst. .

In general, it is known to adjust the concentration of hydrogen acting as a chain transfer agent during polymerization in order to control the molecular weight of the polymer. However, it is known that when the hydrogen concentration is increased, the molecular weight distribution becomes wider (for example, JP 2000-1506 A, JP 6-316606 A, etc.).
In contrast, the present invention can be obtained by adding hydrogen to the reaction system when polymerizing an aromatic vinyl monomer in the presence of a group 3 transition metal complex using a powder bed continuous polymerization apparatus. The molecular weight distribution of the aromatic vinyl compound polymer becomes unexpectedly narrow. Although this mechanism of action is not clear, it is estimated as follows.

When chain transfer occurs during polymerization using a catalyst, polymers with various molecular chain lengths are formed, but if the ratio between the growth rate of the molecular chain and the chain transfer rate is always constant, the molecular weight distribution is almost constant. 2.0. The mechanism of chain transfer at the time of polymerization is roughly classified into β hydrogen elimination and β hydrogen transfer by the action of a catalyst, and molecular chain scission or exchange by a chain transfer agent. In a half titanocene catalyst, chain transfer occurs mainly due to β hydrogen transfer, and therefore a polymer having a narrow molecular weight distribution can be produced regardless of the polymerization mode.
On the other hand, in the case of a catalyst in which β-hydrogen elimination and β-hydrogen transfer due to the action of the catalyst hardly occur, living polymerization occurs by itself, and chain transfer occurs when combined with a chain transfer agent. However, when such a catalyst that causes living polymerization is applied to a powder bed continuous polymerization apparatus, the concentration ratio between the monomer molecule and the chain transfer agent in the vicinity of the catalyst changes due to the difference in diffusion rate, and the length of the molecular chain Various polymers are formed, and the molecular weight distribution is widened. On the other hand, in the present invention, by adding hydrogen gas to the reaction system, hydrogen molecules move between the monomer molecules, and chain transfer by hydrogen is positively performed, whereby the chain transfer sufficiently proceeds. Therefore, it is considered that the number of polymers having a short molecular chain increases and the molecular weight distribution becomes narrow.
When a half titanocene catalyst is used and the hydrogen gas is added to the reaction system, the molecular weight distribution is widened. The reason for this is presumed that chain transfer due to hydrogen occurs in addition to chain transfer due to β hydrogen transfer, resulting in excessive chain transfer and excessively low molecular weight polymer.

[Catalyst composition]
The catalyst composition used in the present invention contains (A) a group 3 transition metal complex and (B) a cocatalyst, and further contains (D) an organoaluminum compound as necessary.

((A) Group 3 transition metal complex)
The group 3 transition metal complex used as the component (A) is a complex having a group 3 transition metal or a lanthanoid series transition metal, and is preferably a complex represented by the following general formula (I).
RMX _a-1 Y _b (I)
[Wherein, R represents a cyclopentadienyl-based π ligand, M represents a group 3 or lanthanoid series transition metal in the periodic table, X represents a monoanionic ligand, and Y represents a Lewis base. Show. a represents the valence of M, and b represents 0, 1 or 2. ]

  Examples of the monoanionic ligand represented by X include a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and an aryloxy group having 6 to 20 carbon atoms. , An amide group having 1 to 20 carbon atoms, a silyl group having 1 to 20 carbon atoms, a phosphide group having 1 to 20 carbon atoms, a sulfide group having 1 to 20 carbon atoms, an acyl group having 1 to 20 carbon atoms, and the like. Examples of the Lewis base represented by Y include amines, ethers, phosphines, thioethers, and the like.

  Examples of the halogen atom include fluorine, chlorine, bromine, iodine and the like. Examples of the hydrocarbon group having 1 to 20 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, n-hexyl group, and n-decyl group. Alkenyl groups such as alkyl groups, allyl groups, isopropenyl groups, aryl groups such as phenyl groups, 1-naphthyl groups, 2-naphthyl groups, aralkyl groups such as benzyl groups, N, N-dimethylaminobenzyl groups, etc. Can be mentioned. Examples of the alkoxy group having 1 to 20 carbon atoms include methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, tert-butoxy group, and n-pentyloxy. Group, n-hexyloxy group, n-heptyloxy group, n-octyloxy group, n-nonyloxy group, n-decyloxy group and the like.

  Examples of the aryloxy group having 6 to 20 carbon atoms include a phenoxy group. Examples of the amide group having 1 to 20 carbon atoms include N-methylamide group and N, N-dimethylamide group. Examples of the silyl group having 1 to 20 carbon atoms include a trimethylsilyl group, a triethylsilyl group, a t-butyldimethylsilyl group, a trimethylsilylmethyl group, and a bis (trimethylsilyl) methyl group. Examples of the phosphide group having 1 to 20 carbon atoms include a diphenyl phosphide group. As a C1-C20 sulfide group, a phenyl sulfide group etc. are mentioned, for example. As a C1-C20 acyl group, an acetyl group, a propionyl group, a butyryl group etc. are mentioned, for example.

  M is preferably a metal belonging to Group 3 of the periodic table, more preferably scandium or yttrium, and still more preferably scandium.

  R in the general formula (I) is represented by a substituted cyclopentadienyl π ligand, a substituted indenyl π ligand, or any one of the following general formulas (II), (III), or (IV). A condensed polycyclic cyclopentadienyl π ligand is preferred.

In the general formulas (II) to (IV), R ^{1 to} R ³³ are each a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, carbon An alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a thioalkoxy group having 1 to 20 carbon atoms, a thioaryloxy group having 6 to 20 carbon atoms, an amino group, an amide group, a carboxyl group, or an alkylsilyl group R ^{1 to} R ³³ may be the same as or different from each other, and c, d, e, and f represent an integer of 1 or more, preferably an integer of 1 to 3, and more preferably 2.

  In the general formulas (II) to (IV), examples of the aliphatic hydrocarbon group having 1 to 20 carbon atoms include a methyl group, an ethyl group, a propyl group, an n-butyl group, an isobutyl group, a pentyl group, and a hexyl group. Alkyl groups such as cyclohexyl group and octyl group; alkenyl groups such as vinyl group, propenyl group and cyclohexenyl group. Examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms include aralkyl groups such as benzyl group, phenethyl group and phenylpropyl group; tolyl group, dimethylphenyl group, trimethylphenyl group, ethylphenyl group, propylphenyl group, butyl Examples include alkyl-substituted phenyl groups such as phenyl group and tri-t-butylphenyl group; phenyl group, biphenyl group, naphthyl group, methylnaphthyl group, anthracenyl group, phenanthonyl group and the like. Examples of the thioalkoxy group having 1 to 20 carbon atoms include a thiomethoxy group. Examples of the thioaryloxy group having 6 to 20 carbon atoms include a thiophenoxy group. Specific examples of the halogen atom, the alkoxy group having 1 to 20 carbon atoms, the aryloxy group having 6 to 20 carbon atoms, and the alkylsilyl group are the same as those described in the general formula (I).

  Specific examples of the condensed polycyclic cyclopentadienyl π ligand of the general formula (II) include 4,5,6,7-tetrahydroindenyl group, 1-methyl-4,5,6,7- Tetrahydroindenyl group, 1,2-dimethyl-4,5,6,7-tetrahydroindenyl group, 1,3-dimethyl-4,5,6,7-tetrahydroindenyl group, 1,2,3-trimethyl -4,5,6,7-tetrahydroindenyl group, 2-methyl-4,5,6,7-tetrahydroindenyl group, 1-ethyl-4,5,6,7-tetrahydroindenyl group, 1- Ethyl-2-methyl-4,5,6,7-tetrahydroindenyl group, 1-ethyl-3-methyl-4,5,6,7-tetrahydroindenyl group, 1-ethyl-2,3-dimethyl- 4,5,6,7-tetrahydroindenyl 1,2-diethyl-4,5,6,7-tetrahydroindenyl group, 1,2-diethyl-3-methyl-4,5,6,7-tetrahydroindenyl group, 1,3-diethyl-4 5,6,7-tetrahydroindenyl group, 1,3-diethyl-2-methyl-4,5,6,7-tetrahydroindenyl group, 1,2,3-triethyl-4,5,6,7 -Tetrahydroindenyl group, 2-ethyl-4,5,6,7-tetrahydroindenyl group, 1-methyl-2-ethyl-4,5,6,7-tetrahydroindenyl group, 1,3-dimethyl- 2-ethyl-4,5,6,7-tetrahydroindenyl group, tetrahydropentalenyl group, 1-methyltetrahydropentalenyl group, 2-methyltetrahydropentalenyl group, 1,2-dimethyltetrahydropentalenyl Group, 1,3-dimethyltetrahydropentalenyl group, 1,2,3-trimethyltetrahydropentalenyl group, hexahydroazurenyl group, 1-methylhexahydroazurenyl group, 2-methylhexahydroazurenyl group 1,2-dimethylhexahydroazurenyl group, 1,3-dimethylhexahydroazurenyl group, 1,2,3-trimethylhexahydroazurenyl group and the like.

  Specific examples of the condensed polycyclic cyclopentadienyl π ligand of the general formula (III) include tricyclo [6,4,0,0] dodecadienyl group, 2-methyltricyclo [6,4,0, 0] dodecadienyl group and the like.

  Specific examples of the condensed polycyclic cyclopentadienyl π ligand of the general formula (IV) include 1,2,3,4-tetrahydrofluorenyl group, 9-methyl-1,2,3,4 -Tetrahydro-1-fluorenyl group, 9-ethyl-1,2,3,4-tetrahydro-1-fluorenyl group, 9-n-propyl-1,2,3,4-tetrahydro-1-fluorenyl group, 9- Isopropyl-1,2,3,4-tetrahydro-1-fluorenyl group, 1,2,3,8-tetrahydrocyclopenta [α] indene, 8-methyl-1,2,3,8-tetrahydrocyclopenta [α Indene, 8-ethyl-1,2,3,8-tetrahydrocyclopenta [α] indene, 8-n-propyl-1,2,3,8-tetrahydrocyclopenta [α] indene, 8-phenyl-1 , 2,3 , 8-tetrahydrocyclopenta [α] indene, 8-trimethylsilyl-1,2,3,8-tetrahydrocyclopenta [α] indene, 4a, 5,6,7,8,9-hexahydrobenzo [α] azurenyl Group, 10-methyl-4a, 5,6,7,8,9-hexahydrobenzo [α] azurenyl group, 10-ethyl-4a, 5,6,7,8,9-hexahydrobenzo [α] azurenyl Group, 10-n-propyl-4a, 5,6,7,8,9-hexahydrobenzo [α] azurenyl group, 10-phenyl-4a, 5,6,7,8,9-hexahydrobenzo [α ] Azulenyl group, 10-trimethylsilyl-4a, 5,6,7,8,9-hexahydrobenzo [α] azurenyl group and the like.

  Among the condensed polycyclic cyclopentadienyl π ligands, a ligand represented by the general formula (IV) is particularly preferable, and a ligand having an alicyclic 6-membered ring structure, that is, the following general formula The ligand represented by the formula (V) is most preferable in view of polymerization activity, complex stability, and production cost.

In the general formula (V), R ^{34 to} R ⁴⁶ are a hydrogen atom, a halogen atom, an aliphatic hydrocarbon group having 1 to 20 carbon atoms, an aromatic hydrocarbon group having 6 to 20 carbon atoms, or 1 to 20 carbon atoms. An alkoxy group, an aryloxy group having 6 to 20 carbon atoms, a thioalkoxy group having 1 to 20 carbon atoms, a thioaryloxy group having 6 to 20 carbon atoms, an amino group, an amide group, a carboxyl group, or an alkylsilyl group. Specific examples of these substituents include those exemplified with respect to the general formulas (II) to (IV).

  Specific examples of the half metallocene type scandium complex represented by the general formula (I) include (pentamethylcyclopentadienyl) bis (N, N-dimethylaminobenzyl) scandium, (2,3,4,5- Tetramethyl-1-trimethylsilylcyclopentadienyl) bis (N, N-dimethylaminobenzyl) scandium, (1,3-dimethyltetrahydropentalenyl) bis (N, N-dimethylaminobenzyl) scandium, (tricyclo [6 , 4,0,0] dodecadienyl) bis (N, N-dimethylaminobenzyl) scandium, (1,2,3,4-tetrahydroindenyl) bis (N, N-dimethylaminobenzyl) scandium, (1,2 , 3,8-Tetrahydrocyclopenta [α] indenyl) bis (N, N-dimethylamino) (Benzyl) scandium, (8-methyl-1,2,3,8-tetrahydrocyclopenta [α] indenyl) bis (N, N-dimethylaminobenzyl) scandium, (1,2,3,4-tetrahydro-1- Fluorenyl) bis (N, N-dimethylaminobenzyl) scandium, (9-methyl-1,2,3,4-tetrahydro-1-fluorenyl) bis (N, N-dimethylaminobenzyl) scandium, (9-ethyl- 1,2,3,4-tetrahydro-1-fluorenyl) bis (N, N-dimethylaminobenzyl) scandium, (9-n-propyl-1,2,3,4-tetrahydro-1-fluorenyl) bis (N , N-dimethylaminobenzyl) scandium, (9-isopropyl-1,2,3,4-tetrahydro-1-fluorenyl) (N, N-dimethylaminobenzyl) scandium, (9-trimethylsilyl-1,2,3,4-tetrahydro-1-fluorenyl) bis (N, N-dimethylaminobenzyl) scandium, (4a, 5,6, 7,8,9-hexahydrobenzo [α] azurenyl) bis (N, N-dimethylaminobenzyl) scandium, (9-methyl-1,2,3,4-tetrahydro-1-fluorenyl) bis (trimethylsilylmethyl) Scandium, (9-ethyl-1,2,3,4-tetrahydro-1-fluorenyl) bis (trimethylsilylmethyl) scandium, (9-n-propyl-1,2,3,4-tetrahydro-1-fluorenyl) bis (Trimethylsilylmethyl) scandium, (9-trimethylsilyl-1,2,3,4-tetrahydro -1-fluorenyl) bis (trimethylsilylmethyl) scandium, (9-methyl-1,2,3,4-tetrahydro-1-fluorenyl) bis (allyl) scandium, (9-ethyl-1,2,3,4) Tetrahydro-1-fluorenyl) bis (allyl) scandium, (9-n-propyl-1,2,3,4-tetrahydro-1-fluorenyl) bis (allyl) scandium, (9-isopropyl-1,2,3, 4-tetrahydro-1-fluorenyl) bis (allyl) scandium, (9-trimethylsilyl-1,2,3,4-tetrahydro-1-fluorenyl) bis (allyl) scandium, and the like. These may be used individually by 1 type, and may be used in combination of 2 or more types.

((B) promoter)
In the catalyst composition, examples of the promoter used as the component (B) include (B-1) a non-coordinating ionic compound or (B-2) an organoaluminum oxy compound.

<(B-1) Non-coordinating ionic compound>
The (B-1) non-coordinating ionic compound used as the (B) promoter may react with the contact product of the component (A) and the component (D) to form an ionic complex. An ionic compound composed of a non-coordinating anion and a cation is used. Examples of the compound include an ionic compound composed of a non-coordinating anion and a substituted or unsubstituted triarylcarbenium, and an ionic compound composed of a non-coordinating anion and a substituted or unsubstituted anilinium.

Examples of the non-coordinating anion include a non-coordinating anion represented by the following general formula (VI).
(BZ ¹ Z ² Z ³ Z ⁴ ) ^- (VI)
In the general formula (VI), Z ^{1 to} Z ⁴ are each a hydrogen atom, a dialkylamino group, an alkoxy group, an aryloxy group, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms (halogen substitution). An aryl group), an alkylaryl group, an arylalkyl group, a substituted alkyl group and an organic metalloid group or a halogen atom.

  Specific examples of the non-coordinating anion represented by the general formula (VI) include tetrakis (fluorophenyl) borate, tetrakis (difluorophenyl) borate, tetrakis (trifluorophenyl) borate, and tetrakis (tetrafluorophenyl) borate. , Tetrakis (pentafluorophenyl) borate, tetrakis (trifluoromethylphenyl) borate, tetra (toluyl) borate, tetra (xylyl) borate, (triphenyl, pentafluorophenyl) borate, [tris (pentafluorophenyl), phenyl] Examples thereof include borates and tridecahydride-7,8-dicarbaoundecaborate.

Examples of the substituted or unsubstituted triarylcarbenium include triarylcarbenium represented by the following general formula (VII).
[CR ⁴⁷ R ⁴⁸ R ⁴⁹ ] ⁺ (VII)
In the general formula (VII), R ⁴⁷ , R ⁴⁸ and R ⁴⁹ are each an aryl group such as a phenyl group, a substituted phenyl group, a naphthyl group and an anthracenyl group, and they may be the same or different from each other. May be.

The substituted phenyl group can be represented, for example, by the following general formula (VIII).
C ₆ H _5-k R ⁵⁰ _k (VIII)
In the general formula (VIII), R ⁵⁰ represents a hydrocarbyl group having 1 to 10 carbon atoms, an alkoxy group, an aryloxy group, a thioalkoxy group, a thioaryloxy group, an amino group, an amide group, a carboxyl group, or a halogen atom. , K is an integer of 1-5. When k is 2 or more, the plurality of R ⁵⁰ may be the same or different.

Specific examples of the substituted or unsubstituted triarylcarbenium represented by the general formula (VII) include tri (phenyl) carbenium, tri (toluyl) carbenium, tri (methoxyphenyl) carbenium, tri (chlorophenyl) carbenium, Tri (fluorophenyl) carbenium, tri (xylyl) carbenium, [di (toluyl), phenyl] carbenium, [di (methoxyphenyl), phenyl] carbenium, [di (chlorophenyl), phenyl] carbenium, [toluyl, di (phenyl) )] Carbenium, [methoxyphenyl, di (phenyl)] carbenium, [chlorophenyl, di (phenyl)] carbenium and the like.
Specific examples of substituted or unsubstituted anilinium include N, N-dimethylanilinium.

Specific examples of the ionic compound comprising a non-coordinating anion and a cation include tri (phenyl) carbenium tetrakis (pentafluorophenyl) borate, tri (4-methylphenyl) carbenium tetrakis (pentafluorophenyl) borate, Examples include tri (4-methoxyphenyl) carbenium tetrakis (pentafluorophenyl) borate, N, N-dimethylanilinium tetrakis (pentafluorophenyl) borate, N, N-diethylanilinium tetrakis (pentafluorophenyl) borate and the like. .
In this invention, the ionic compound which consists of a non-coordinating anion and a cation of (B-1) component may be used individually by 1 type, and may be used in combination of 2 or more type.

<(B-2) Organoaluminum oxy compound>
Examples of the (B-2) organoaluminum oxy compound used as the (B) promoter include aluminoxane.
The aluminoxane is preferably an alkylaluminoxane, and examples thereof include methylaluminoxane (MAO) and modified methylaluminoxane. As the modified methylaluminoxane, MMAO-3A (trade name, manufactured by Tosoh Finechem Co., Ltd.) and the like can be preferably used.

((D) Organoaluminum compound)
In the catalyst composition, examples of the organoaluminum compound (D) used as necessary include an organoaluminum compound represented by the following general formula (IX).
R'R''R '''Al (IX)
In the general formula (IX), R ′, R ″ and R ′ ″ each independently represents an alkyl group having 3 to 5 carbon atoms. It is preferable that the alkyl group has 3 to 5 carbon atoms because sufficient polymerization activity can be obtained. Examples of the alkyl group having 3 to 5 carbon atoms include various propyl groups, various butyl groups, and various pentyl groups.

Examples of the organoaluminum compound of component (D) include tri-n-propylaluminum, triisopropylaluminum, tri-n-butylaluminum, triisobutylaluminum, tri-t-butylaluminum, and tri-n-pentylaluminum. Can be mentioned. Among these, an aluminum compound having only a substituent having 4 carbon atoms is preferable because excellent activity is obtained, and tri-n-butylaluminum and triisobutylaluminum are more preferable.
In this invention, these organoaluminum compounds may be used individually by 1 type, and may be used in combination of 2 or more type.

(Preparation of catalyst composition)
In the preparation of the catalyst composition, the component (A) is brought into contact with the component (B). The amount of component (B-1) used is preferably in the range of 1.0 to 1.5 molar ratio to component (A) from the viewpoint of catalytic activity, The amount is preferably in the range of 5 to 1000 molar ratio to the component (A). The contact time when the component (A) and the component (B) are contacted is usually about 1 minute to 60 minutes, and the temperature condition is usually 0 to 50 ° C.
When the component (D) is used, the component (A) and the component (D) are contacted so that the component (D) / (A) component (molar ratio) is 5 or more, and then the component (B) is added. It is preferable to make it contact. The component (D) / component (A) (molar ratio) is preferably 5 to 300, more preferably 10 to 300, from the viewpoint of catalyst activity and storage stability of the catalyst. The contact time when the component (A) and the component (D) are contacted is usually about 1 minute to 60 minutes, and the temperature condition is usually 0 to 50 ° C.

When preparing the catalyst composition, it is desirable to perform the contact operation in an inert gas atmosphere such as nitrogen gas. And as for each of these catalyst components, those prepared in advance in a catalyst preparation tank may be used, or those prepared in a polymerization reactor for polymerizing aromatic vinyl monomers may be used as they are.
When the catalyst composition is prepared in a catalyst preparation tank, an aromatic vinyl compound in an amount such that the molar ratio to the component (A) is 0.5 to 500 may be used. When the molar ratio is 0.5 or more, a sufficiently high polymerization activity can be obtained even in the polymerization reaction after storing the catalyst. In addition, when an excessive amount of the aromatic vinyl compound is used, the polymerization reaction may proceed during storage of the catalyst and the product may be precipitated, but this precipitation can be suppressed by the molar ratio being 500 or less. The catalyst can be charged to the reactor without adverse effects. From this viewpoint, the molar ratio is preferably 1 to 200, more preferably 1 to 50.

[Method for producing aromatic vinyl compound polymer]
In the method of the present invention, an aromatic vinyl compound polymer is produced by polymerizing an aromatic vinyl monomer in the presence of the catalyst composition using a powder bed continuous polymerization apparatus. In the present specification, the “aromatic vinyl compound polymer” refers to a polymer in which the aromatic vinyl compound monomer unit is 1 mol% or more, specifically, from one kind of aromatic vinyl compound. A homopolymer, a copolymer composed of two or more aromatic vinyl compounds, and a copolymer composed of an aromatic vinyl compound and another monomer (olefin).

(Aromatic vinyl monomer)
There are various types of aromatic vinyl compounds used as the monomer for polymerization, but those represented by the following formula (X) are preferred.

  In formula (X), R represents a hydrogen atom, a halogen atom or a hydrocarbon group having 20 or less carbon atoms, and m represents an integer of 1 to 3. When m is plural, each R may be the same or different.

In the present invention, examples of the aromatic vinyl monomer used as a raw material include styrene, alkyl styrene, aryl styrene, halogenated styrene, alkoxy styrene, and vinyl benzoate.
Specific examples of the alkyl styrene include o-methyl styrene, m-methyl styrene, p-methyl styrene, o-ethyl styrene, m-ethyl styrene, p-ethyl styrene, on-propyl styrene, mn-propyl. Styrene, pn-propyl styrene, o-isopropyl styrene, m-isopropyl styrene, p-isopropyl styrene, mn-butyl styrene, pn-butyl styrene, p-tert-butyl styrene, 4-butenyl styrene 2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,5-dimethylstyrene, mesitylstyrene and the like.
Specific examples of the aryl styrene include p-phenyl styrene.
Specific examples of the halogenated styrene include o-fluorostyrene, m-fluorostyrene, p-fluorostyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, o-bromostyrene, m-bromostyrene, p -Bromostyrene, o-methyl-p-fluorostyrene and the like.
Specific examples of alkoxystyrene include o-methoxystyrene, m-methoxystyrene, p-methoxystyrene and the like.
Of these, styrene is particularly preferred. The said vinyl compound may be used individually by 1 type, and may be used in combination of 2 or more type.

(Olefin monomer)
In the present invention, the aromatic vinyl monomer and the olefin monomer may be combined and copolymerized.
As said olefin type monomer, a C2-C12 substituted or unsubstituted olefin is preferable. Specific examples thereof include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 4-phenyl-1-butene, 6-phenyl- 1-hexene, 3-methyl-1-butene, 4-methyl-1-butene, 3-methyl-1-pentene, 4-methyl-1-pentene, 3-methyl-1-hexene, 4-methyl-1- Hexene, 5-methyl-1-hexene, 3,3-dimethyl-1-pentene, 3,4-dimethyl-1-pentene, 4,4-dimethyl-1-pentene, vinylcyclohexane, hexafluoropropene, tetrafluoroethylene 2-fluoropropene, fluoroethylene, 1,1-difluoroethylene, 3-fluoropropene, trifluoroethylene, 3,4-dichloro-1- Ten, butadiene, isoprene, dicyclopentadiene, norbornene, acetylene and the like. Of these, ethylene, propylene, 1-hexene and 1-octene are preferable. These may be used individually by 1 type and may be used in combination of 2 or more type.

  When copolymerization is performed using an aromatic vinyl compound and an olefin monomer as raw materials, the content of the aromatic vinyl compound unit in the resulting copolymer is 1 mol% or more, preferably 5 to 99 mol%. More preferably, it is 40-95 mol%. That is, the content of the olefin monomer unit is 99 mol% or less, preferably 1 to 95 mol%, more preferably 3 to 60 mol%. When the content of the olefin monomer unit is within the above range, the physical properties of the syndiotactic polystyrene are improved.

(Polymerization conditions)
In the present invention, a powder bed continuous polymerization apparatus is used from the viewpoint of production on an industrial scale. The polymerization temperature is usually in the range of 0 to 200 ° C, preferably 0 to 120 ° C. Moreover, the pressure at the time of superposition | polymerization is 0.01-30 Mpa normally, Preferably it is the range of 0.01-3 Mpa.
Further, in the present invention, the aromatic vinyl monomer is polymerized in the presence of the catalyst composition using a powder bed continuous polymerization apparatus, and the hydrogen partial pressure is preferably about 1 kPa to 1.0 MPa, more preferably Hydrogen is supplied to the reaction system so as to be 10 kPa to 0.5 MPa. By supplying hydrogen to the reaction system at the time of polymerization, the molecular weight distribution (Mw / Mn) of the resulting syndiotactic polymer can be narrowed to preferably 3 or less, more preferably 2.0 to 2.5.

[Aromatic vinyl compound polymer]
The aromatic vinyl compound polymer obtained by the method of the present invention is characterized by having a syndiotactic structure. That is, when repeating units composed of an aromatic vinyl compound contained in the polymer are continuous, the aromatic rings of the repeating units are alternately arranged with respect to the plane formed by the polymer main chain. It is characterized by a high ratio (syndiotacticity). The syndiotacticity can be expressed by stereoregularity [rrrr] (racemic pentad fraction) of a repeating unit chain composed of an aromatic vinyl compound. In the polymer of the present invention, the stereoregularity [rrrr] is usually 80 mol% or more, preferably 95 mol% or more, more preferably 98 mol% or more. When it is less than 80 mol%, the heat resistance, which is a characteristic of the syndiotactic structure, is lowered.
The stereoregularity [rrrr] is a racemic fraction (mol%) of pentad (five-chain) units in the aromatic vinyl compound polymer, and is an index representing the stereoregularity distribution. This stereoregularity [rrrr] can be calculated by measuring a ¹³ C-NMR spectrum in accordance with the method proposed by A. Zambelli et al. In “Macromolecules, 6,925 (1973)”. it can. Specifically, it is represented by the fraction of the peak excluding noise (satellite peak and spinning side band) in the phenyl C1 carbon region (146.3 ppm to 144.5 ppm) of the styrene chain in the copolymer.

The aromatic vinyl compound polymer of the present invention has a molecular weight distribution (Mw / Mn) measured by GPC method of usually 3 or less, preferably 2.0 to 2.5, by supplying hydrogen to the reaction system. is there.
The molecular weight distribution is given by the ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by gel permeation chromatography (GPC). GPC is measured using, for example, a GPC column Shodex UT806L (trade name, manufactured by GL Sciences Inc.), a temperature of 145 ° C., a solvent 1,2,4-trichlorobenzene, a flow rate of 1.0 ml / min. Can be performed under the following conditions.

In addition, the weight average molecular weight of the aromatic vinyl compound polymer of the present invention is not particularly limited, but from the viewpoint of impact resistance, the weight average molecular weight in terms of polystyrene is usually 10,000 to 3,000,000, preferably 50,000 to 90. It is in the range of 10,000.
The weight average molecular weight can be determined by measuring intrinsic viscosity [η], which is an index of molecular weight. In the Examples, the intrinsic viscosity [η] is a viscometer (manufactured by Rouai Co., Ltd., trade name: “VMR-053U-PC · F01”), Ubbelohde viscosity tube (time volume of bulb: 2-3 ml, capillary tube) (Diameter: 0.44 to 0.48 mm), 1,2,4-trichlorobenzene was used as a solvent, and a 0.02 to 0.16 g / dL solution was measured at 145 ° C. When the aromatic vinyl compound polymer of the present invention is expressed by intrinsic viscosity [η], it is usually 0.1 to 16 dl / g (10,000 to 3 million in weight average molecular weight), preferably 0.2 to 5.0 dl / g. g (weight average molecular weight of 50,000 to 900,000).

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.

Production Example 1
[Synthesis of o-N, N-dimethylaminobenzyllithium]
N-BuLi in hexane (2.6 mol / L, 50 ml) was added dropwise over 25 minutes to a solution of N, N-dimethyl-o-toluidine (18 ml, 0.12 mmol) in hexane (50 ml) -diethyl ether (16 ml). did. After stirring for 45 hours, the precipitate was separated by filtration. The obtained solid was washed with hexane (40 ml × 3 times) and then dried under reduced pressure to obtain 13 g (yield 77%) of dimethylaminobenzyllithium.

Production Example 2
Synthesis of tris (o-N, N- dimethylamino-benzyl) scandium _{(Sc (CH 2 C 6 H} 4 N (CH 3) 2 -o) 3)]
A suspension of anhydrous ScCl ₃ (1.0 g, 6.6 mmol) in tetrahydrofuran (THF) (10 ml) was stirred at room temperature for 1 hour, to which o-N, N-dimethylaminobenzyllithium synthesized in Production Example 1 ( 2.8 g, 20 mmol) in THF was added dropwise and stirred for 12 hours. The solvent was distilled off, followed by extraction with toluene, and further purification by recrystallization to obtain tris (o-N, N-dimethylaminobenzyl) scandium as pale yellow crystals. The yield was 80%.

Production Example 3
[Synthesis of (1,2,3,4-tetrahydrofluorenyl) bis (o-N, N-dimethylaminobenzyl) scandium]
To 10 ml of a THF solution of tris (o-N, N-dimethylaminobenzyl) scandium (6.21 g, 13.8 mmol) obtained in Production Example 2, 1,2,3,4-tetrahydrofluorene (1.79 g, 13.8 mmol) of THF solution was added and stirred at 70 ° C. for 12 hours. After completion of the reaction, the solvent was removed, extracted with 50 ml of hexane, and further purified by recrystallization to obtain (1,2,3,4-tetrahydrofluorenyl) bis (o-N, N-dimethylaminobenzyl) scandium. Obtained as pale yellow crystals. The yield was 64%.

Examples 1-4
(1) Preparation of catalyst solution The temperature of the catalyst preparation tank (50 L) with a jacket of a pilot apparatus was set to 25 degreeC, and ethylbenzene 13.7L was put into this catalyst preparation tank. Thereafter, 1.82 mol (1.82 L of toluene solution) of trinormalbutylaluminum (TNBA) and 0.36 mol (0.052 L of toluene solution) of styrene monomer (SM) were obtained in Production Example 3 (1, 2, 0.014-mol (3,48-tetrahydrofluorenyl) bis (o-N, N-dimethylaminobenzyl) scandium (0.228 L of toluene solution), 0.022 mol of N, N-dimethylanilinium tetrakispentafluorophenylborate (Ethylbenzene suspension 3.9 L) was added in this order to prepare a catalyst solution, which was further diluted with ethylbenzene to make 26.0 L as a whole (0.7 mmol-Sc / L as the catalyst solution).

(2) Polymerization of styrene A double helical blade having a blade width of 55 mm and a bottom inclination angle of 30 degrees was attached to a cleaned stirred tank reactor (volume: 254 L, tank diameter: 550 mm, height: 1155 mm). Then, the reactor was purged with nitrogen for 2 hours or more with nitrogen gas for O ₂ purge in the reactor. Thereafter, warm water of 40 ° C. is passed through the reactor jacket, the rotational speed is lowered to 10 rpm, and syndiotactic polystyrene (SPS) powder is introduced into the reactor as seed powder for powder bed polymerization. The temperature was raised to 90 ° C. and further dried for 2 hours under a nitrogen stream. After drying, the jacket temperature was adjusted to 70 ° C. and the operating rotational speed shown in Table 1.
Thereafter, styrene monomer (SM) 8 L / h was used as a raw material, and the TNBA (tri-normal butylaluminum) solution was adjusted so that n (mol-Sc / 350 kmol-SM) was a set value shown in Table 1. Al / SM (mol / 350 kmol) was supplied so as to have a set value shown in Table 1. The supply amount of the TNBA solution was adjusted in consideration of the amount of TNBA brought from the catalyst solution. Subsequently, after atmospheric purging of the reactor, the pressure was set to 130 kPa-G, and supply of hydrogen was started after about 24 hours, and the pressure was adjusted to the set hydrogen partial pressure shown in Table 1.
The generated powder was discharged intermittently from the bottom of the tank, and the molecular weight and molecular weight distribution of the powder and the measurement of syndiotacticity ([rrrr]) were carried out according to the method described herein.
Catalyst solution concentration: 0.7 mmol-Sc / L, TNBA solution concentration: 0.6 mol / L

  From Table 1, it was confirmed that when the hydrogen partial pressure was set high under the same Al / SM conditions, the molecular weight distribution and molecular weight distribution of the SPS powder were reduced.

Example 5
SPS powder was produced in the same manner as in Example 1 except that the catalyst adjustment conditions and reaction conditions were changed as shown in Table 2. The results are shown in Table 2.

Comparative Examples 1 and 2
SPS powder was produced in the same manner as in Example 1 except that the hydrogen supply was not performed and the reaction conditions were changed as shown in Table 3. The results are shown in Table 3.

  From Tables 1-3, according to the method of the present invention, an aromatic vinyl compound polymer having a syndiotactic structure with a narrow molecular weight distribution in the presence of a Group 3 transition metal complex is obtained using a powder bed continuous polymerization apparatus. It turns out that it can manufacture efficiently.

  According to the method of the present invention, an aromatic vinyl compound polymer having a syndiotactic structure with a narrow molecular weight distribution can be efficiently produced on an industrial scale.

Claims (6)

A method for producing an aromatic vinyl compound polymer having a syndiotactic structure using a powder bed continuous polymerization apparatus, wherein (A) a group 3 transition metal complex represented by the following general formula (I) and (B) In the presence of a catalyst composition containing a promoter which is (B-1) a non-coordinating ionic compound or (B-2) an organoaluminum oxy compound , an aromatic vinyl monomer is polymerized to obtain the aromatic vinyl compound polymer. A method for producing an aromatic vinyl compound polymer, wherein (C) hydrogen is added to a reaction system during production.
RMX _a-1 Y _b (I)
[Wherein, R represents a cyclopentadienyl-based π ligand, M represents a group 3 or lanthanoid series transition metal in the periodic table, X represents a monoanionic ligand, and Y represents a Lewis base. Show. a represents the valence of M, and b represents 0, 1 or 2. ]   The manufacturing method of the aromatic vinyl compound polymer of Claim 1 whose molecular weight distribution of the obtained aromatic vinyl compound polymer is 3 or less.   The method for producing an aromatic vinyl compound polymer according to claim 1 or 2, wherein the aromatic vinyl monomer is styrene. The method for producing an aromatic vinyl compound polymer according to any one of claims 1 to 3 , wherein the group 3 transition metal complex is a scandium complex. The method for producing an aromatic vinyl compound polymer according to any one of claims 1 to 4, wherein the non-coordinating ionic compound is an ionic compound comprising a non-coordinating anion and a cation. The method for producing an aromatic vinyl compound polymer according to any one of claims 1 to 5 , wherein the catalyst composition further contains (D) an organoaluminum compound.