JP2007063469A - Metallic compound, catalyst composition for vinyl ester monomer polymerization containing metallic compound and use of the composition for polymerization of vinyl ester monomer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catalyst for easily performing syndiotactic polymerization of a vinyl ester monomer such as vinyl acetate under a mild condition. <P>SOLUTION: The invention provides a polymerization catalyst composition suitable for the syndiotactic polymerization of vinyl esters and produced by the reaction of a specific Schiff's base compound having fluorine atom and hydroxyl group such as a compound of formula (XXIII) with a specific coordinate compound containing an element selected from the group 3 to 11 elements of the periodic table and provides a method for producing the catalyst composition. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention relates to a metal compound having a hydroxyl group with an element selected from Groups 3 to 11 of the periodic table, a vinyl ester monomer polymerization catalyst composition containing the metal compound, and a vinyl ester monomer using the same. The present invention relates to a syndiotactic polymerization method.

  In general, polymers of vinyl ester monomers such as vinyl acetate are converted to polyvinyl alcohol (PVA) by saponification, and are used in various fields such as fibers, films, and adhesives. It is known that the physical properties of PVA vary greatly depending on the stereoregularity of the hydroxyl group that is the side chain of the polymer. For example, PVA rich in isotacticity or syndiotacticity is superior in terms of strength, heat resistance and the like as compared to an atactic polymer.

  As an addition polymerization method for vinyl ester monomers, radical polymerization is known. However, the radical polymerization method has limitations in stereoregularity control, and it is necessary to use a special solvent to obtain a high degree of stereoregularity. Accordingly, it is difficult to control stereoregularity under simple and mild conditions. For example, JP-A-11-147913 (Patent Document 1) reports that a polyvinyl alcohol rich in syndiotacticity can be obtained by adding a fluorine-containing branched alcohol to a radical polymerization system of a vinyl ester monomer. However, in order to express the effect of the fluorine-containing branched alcohol, it is necessary to add 30 to 80 parts by volume of an expensive fluorine-containing branched alcohol. Incidentally, the syndiotacticity of PVA obtained from the radical polymerization of vinyl acetate, which is usually used industrially, shows 53% with racemo diads (r), and does not exceed 55% even when the polymerization temperature is changed.

  On the other hand, coordination polymerization represented by polymerization using a Ziegler-Natta catalyst or a metallocene catalyst is known to be relatively easy to control stereoregularity. For this reason, some attempts have been made to conduct stereoregular polymerization of vinyl ester monomers using a transition metal catalyst. For example, Industrial Chemical Journal, Vol. 65, p. 74, 1962 (Non-patent Document 1), Z . Anorg. Allorg. Chem. 629, 781, 2003 (Non-Patent Document 2), Polym. Prepr. Jpn. 46, 1311, 1997 (non-patent document 3). These reports only mention that the polymer can be obtained in a yield of 5 to 10%, and none of them reveals the stereoregularity of the produced polymer. From the expression mechanism of syndiospecific polymerization, it is presumed that polyvinyl acetate having high syndiotacticity has not been obtained.

  JP-A-3-296505 (Patent Document 2) reports a method for producing an ethylene-vinyl acetate copolymer using a rhodium compound as a catalyst. Although it is described that the vinyl acetate content in the ethylene-vinyl acetate copolymer obtained by this method can be controlled to 0.001 to 50%, homopolymerization of vinyl acetate and ethylene-vinyl acetate copolymer The length of the vinyl acetate chain in the coalescence and its stereoregularity are unknown.

JP-A-11-147913 JP-A-3-296505 Industrial Chemical Journal, 65, 74, 1962 Z. Anorg. Allorg. Chem. 629, 781, 2003 Polym. Prepr. Jpn. 46, 1311, 1997

  Therefore, the problem of the present invention is to solve the problems of the prior art as described above, and the syndiotacticity is high from vinyl ester monomers due to a milder condition and a small amount of fluorine-containing branched hydroxyl group, and the quality, physical properties It is an object of the present invention to provide a polymerization catalyst composition capable of producing a PVA with good quality and the like, and a method for producing a polymer having a high syndiotacticity.

［式（Ｉ）〜（ＸＩ）中、Ｒ^１〜Ｒ^７は、それぞれ水素、置換基を有してもよい炭素数１〜２０の脂肪族炭化水素基、置換基を有してもよい炭素数６〜２０の芳香族炭化水素基、炭素数１〜２０のアルコキシ基または炭素数６〜２０のアリロキシ基を表し、Ｘ^１は周期律表第１族の元素を表し、Ｙ^１およびＹ^２は、それぞれ下記式（ＸＩＩ）または（ＸＩＩＩ）：

（式（ＸＩＩ）〜（ＸＩＩＩ）中、Ｒ^８は置換基を有してもよい炭素数０〜２０の２価の脂肪族炭化水素基または置換基を有してもよい炭素数６〜２０の２価の芳香族炭化水素基を表し、Ｒ^９、Ｒ^１０およびＲ^１１は、それぞれ、水素、フッ素、塩素、置換基を有してもよい炭素数１〜２０の脂肪族炭化水素基、または置換基を有してもよい炭素数６〜２０の芳香族炭化水素基を表す。）で表される基を表す。］で示される水酸基を有するフッ素含有化合物からなる群から選ばれた少なくとも１種の化合物（Ａ１）と、
下記式（ＸＩＶ）：
ＭＸ^２ _ａＬ_ｂ （ＸＩＶ）
（式（ＸＩＶ）中、Ｍは周期律表第３族〜１１族から選ばれた元素を表し、Ｘ^２は水素、置換基を有してもよい炭素数１〜２０の脂肪族炭化水素基、置換基を有してもよい炭素数６〜２０の芳香族炭化水素基、またはハロゲン原子を表し、Ｘ^２の数を示すａは１〜６を表し、ａが２〜６のときＸ^２は互いに同一でも異なっていてもよく、Ｌは金属に対して配位結合可能な化合物を表し、Ｌの数を示すｂは０〜８を表す。）で示される化合物からなる群から選ばれた少なくとも１種の化合物（Ａ２）との反応により得られる金属化合物を含む成分Ａを含有する、前記重合用触媒組成物に関する。 That is, the present invention is a catalyst composition for syndiotactic polymerization of vinyl ester monomers, which comprises the following formulas (I), (II), (III), (IV), (V), (VI), ( VII), (VIII), (IX), (X) and (XI):

[In formulas (I) to (XI), R ^{1 to} R ⁷ are each hydrogen, an optionally substituted aliphatic hydrocarbon group having 1 to 20 carbon atoms, or an optionally substituted carbon. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms or an allyloxy group having 6 to 20 carbon atoms, X ¹ represents an element of Group ¹ of the periodic table, and Y ¹ and Y ² Are the following formulas (XII) or (XIII):

(In formulas (XII) to (XIII), R ⁸ may have a divalent aliphatic hydrocarbon group having 0 to 20 carbon atoms which may have a substituent or a substituent having 6 to 20 carbon atoms. R ⁹ , R ¹⁰ and R ¹¹ are each hydrogen, fluorine, chlorine, an optionally substituted aliphatic hydrocarbon group having 1 to 20 carbon atoms, Or represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. At least one compound (A1) selected from the group consisting of fluorine-containing compounds having a hydroxyl group represented by:
Formula (XIV):
MX ² _a L _b (XIV)
(In the formula (XIV), M represents an element selected from Groups 3 to 11 of the periodic table, and X ² is hydrogen and an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a substituent. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent, or a halogen atom, a representing the number of X ² represents 1 to 6, and when a is 2 to 6, X ² May be the same as or different from each other, L represents a compound capable of coordinating bond to a metal, and b representing the number of L represents 0 to 8). It is related with the said catalyst composition for polymerization containing the component A containing the metal compound obtained by reaction with an at least 1 sort (s) of compound (A2).

（式（ＸＶ）中、Ｒ^８は置換基を有してもよい炭素数０〜２０の２価の脂肪族炭化水素基、または置換基を有してもよい炭素数６〜２０の２価の芳香族炭化水素基を表す。）で表される基である、前記の重合用触媒組成物に関する。 In the present invention, at least one of Y ¹ and Y ² of component A1 is represented by the following formula (XV):

(In formula (XV), R ⁸ is a divalent aliphatic hydrocarbon group having 0 to 20 carbon atoms which may have a substituent, or a divalent group having 6 to 20 carbon atoms which may have a substituent. It is related with the said catalyst composition for polymerization which is group represented by this.

（式（ＸＶＩ）中、Ｒ^１〜Ｒ^５およびＲ^１２〜Ｒ^１５はそれぞれ、水素、置換基を有してもよい炭素数１〜２０の脂肪族炭化水素基、置換基を有してもよい炭素数６〜２０の芳香族炭化水素基、炭素数１〜２０のアルコキシ基または炭素数６〜２０のアリロキシ基を表し、Ｘ^２は、水素、置換基を有してもよい炭素数１〜２０の脂肪族炭化水素基、置換基を有してもよい炭素数６〜２０の芳香族炭化水素基またはハロゲン原子を表し、Ｘ^２の数を示すaは１〜６を表し、ａが２〜６のときＸ^２は互いに同一でも異なっていてもよく、Ｍは周期律表第３族〜１１族から選ばれた元素を表し、Ｘ^３は酸素または水酸基を表す。）で示される金属化合物からなる群から選ばれた少なくとも１種の金属化合物である、前記重合用触媒組成物に関する。 Further, in the present invention, the component A is represented by the following formula (XVI):

(In Formula (XVI), R ^{1 to} R ⁵ and R ^{12 to} R ¹⁵ may each have hydrogen, a C 1-20 aliphatic hydrocarbon group that may have a substituent, or a substituent. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an allyloxy group having 6 to 20 carbon atoms, and X ² is hydrogen and may have a substituent. Represents an aliphatic hydrocarbon group of -20, an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent, or a halogen atom, a representing the number of X ² represents 1 to 6, and a represents 2 to 6, X ² may be the same or different from each other, M represents an element selected from Groups 3 to 11 of the periodic table, and X ³ represents oxygen or a hydroxyl group. The polymerization catalyst composition is at least one metal compound selected from the group consisting of compounds. That.

  The present invention also relates to the polymerization catalyst composition, wherein M is iron, cobalt, rhodium or palladium.

Furthermore, the present invention provides
(A) an atomic number of 3 or more and at least one element selected from elements of Groups 1, 2, 11, 12 and 13 of the periodic table, (b) carbon number which may have a substituent 1 to 20 aliphatic hydrocarbon groups and / or an aromatic hydrocarbon group having 6 to 40 carbon atoms which may have a substituent and (c) a perchloric acid group, at least 2 of 3 groups The present invention relates to the above-mentioned polymerization catalyst composition, further comprising Component B containing a compound having an element and / or a group selected from one or more groups.

  Further, the present invention provides the polymerization catalyst composition, wherein Component B is an organolithium compound, an organomagnesium compound, a trifluoromethanesulfonate, a perchlorate, an organozinc compound, an organoboron compound, a borate, or an organoaluminum compound. Related to things.

  Furthermore, the present invention relates to the catalyst composition for polymerization, wherein the syndiotacticity of the polymer is 55% or more by racemo diad (r).

（式（ＸＶＩ）中、Ｒ^１〜Ｒ^５およびＲ^１２〜Ｒ^１５はそれぞれ、水素、置換基を有してもよい炭素数１〜２０の脂肪族炭化水素基、置換基を有してもよい炭素数６〜２０の芳香族炭化水素基、炭素数１〜２０のアルコキシ基または炭素数６〜２０のアリロキシ基を表し、Ｘ^２は、水素、置換基を有してもよい炭素数１〜２０の脂肪族炭化水素基、置換基を有してもよい炭素数６〜２０の芳香族炭化水素基またはハロゲン原子を表し、Ｘ^２の数を示すaは１〜６を表し、ａが２〜６のときＸ^２は互いに同一でも異なっていてもよく、Ｍは周期律表第３族〜１１族から選ばれた元素を表し、Ｘ^３は酸素または水酸基を表す。）で示される金属化合物に関する。 The present invention also provides the following formula (XVI):

(In Formula (XVI), R ^{1 to} R ⁵ and R ^{12 to} R ¹⁵ may each have hydrogen, a C 1-20 aliphatic hydrocarbon group that may have a substituent, or a substituent. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an allyloxy group having 6 to 20 carbon atoms, and X ² is hydrogen and may have a substituent. Represents an aliphatic hydrocarbon group of -20, an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent, or a halogen atom, a representing the number of X ² represents 1 to 6, and a represents 2 to 6, X ² may be the same or different from each other, M represents an element selected from Groups 3 to 11 of the periodic table, and X ³ represents oxygen or a hydroxyl group. Relates to compounds.

  The present invention further relates to the use of the polymerization catalyst composition for syndiotactic polymerization of vinyl ester monomers.

  The present invention also relates to the use of the vinyl ester monomer for syndiotactic polymerization, wherein the vinyl ester monomer is vinyl acetate.

  Furthermore, the present invention relates to the use of the vinyl ester monomer for syndiotactic polymerization, wherein the resulting polymer has a syndiotacticity of 55% or more by racemo diad (r).

  The present invention also provides a method for producing polyvinyl acetate or a copolymer containing vinyl acetate by syndiotactic polymerization of a vinyl ester monomer in the presence of the polymerization catalyst composition, wherein the polymer syndiotacticity is provided. Relates to the above production method, wherein the racemo diad (r) is 55% or more.

  As described above, according to the polymerization catalyst composition of the present invention, a vinyl ester monomer can be polymerized under milder conditions, and a polymer with high syndiotacticity, good quality, physical properties, etc. can be produced. Can do. The obtained polymer is useful for high-strength and high-modulus materials, heat-resistant materials, and the like.

  The fluorine-containing compound (A1) having a hydroxyl group constituting Component A contained in the vinyl ester monomer polymerization catalyst composition of the present invention is at least selected from compounds composed of the following formulas (I) to (XIII): Contains one species.

［式（Ｉ）〜（ＸＩ）中、Ｒ^１〜Ｒ^７は、それぞれ水素、置換基を有してもよい炭素数１〜２０の脂肪族炭化水素基、置換基を有してもよい炭素数６〜２０の芳香族炭化水素基、炭素数１〜２０のアルコキシ基または炭素数６〜２０のアリロキシ基を表し、Ｘ^１は周期律表第１族の元素を表し、Ｙ^１およびＹ^２は、それぞれ下記式（ＸＩＩ）または（ＸＩＩＩ）：

（式（ＸＩＩ）〜（ＸＩＩＩ）中、Ｒ^８は置換基を有してもよい炭素数０〜２０の２価の脂肪族炭化水素基、置換基を有してもよい炭素数６〜２０の２価の芳香族炭化水素基、Ｒ^９、Ｒ^１０およびＲ^１１は、それぞれ、水素、フッ素、塩素、置換基を有してもよい炭素数１〜２０の脂肪族炭化水素基、または置換基を有してもよい炭素数６〜２０の芳香族炭化水素基を表す。）で表される基を表す。］。

[In formulas (I) to (XI), R ^{1 to} R ⁷ are each hydrogen, an optionally substituted aliphatic hydrocarbon group having 1 to 20 carbon atoms, or an optionally substituted carbon. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms or an allyloxy group having 6 to 20 carbon atoms, X ¹ represents an element of Group ¹ of the periodic table, and Y ¹ and Y ² Are the following formulas (XII) or (XIII):

(In the formulas (XII) to (XIII), R ⁸ is a divalent aliphatic hydrocarbon group having 0 to 20 carbon atoms which may have a substituent, and 6 to 20 carbon atoms which may have a substituent. Each of divalent aromatic hydrocarbon groups, R ⁹ , R ¹⁰ and R ¹¹ is hydrogen, fluorine, chlorine, an optionally substituted aliphatic hydrocarbon group having 1 to 20 carbon atoms, or a substituted group Represents a C6-C20 aromatic hydrocarbon group which may have a group). ].

Examples of the aliphatic hydrocarbon group having 1 to 20 carbon atoms of R ^{1 to} R ⁷ include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert- Straight chain, such as butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group, etc. Examples thereof include branched or cyclic aliphatic hydrocarbon groups, and examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms of R ^{1 to} R ⁷ include a phenyl group, a naphthyl group, a biphenyl group, an anthryl group, a phenanthryl group, Indenyl group, fluorenyl group, azulenyl group and the like can be mentioned. Moreover, as a substituent of these groups, said C1-C20 aliphatic hydrocarbon group, said C6-C20 aromatic hydrocarbon group, a methoxy group, an ethoxy group, a propoxy group, a butoxy group , Alkoxy groups such as tert-butoxy group, allyloxy groups such as phenoxy group and naphthoxy group, halogen atoms (F, Cl, Br, I), acetoxy group, sulfonic acid group, carboxyl group, nitrogen-containing group (imino group, nitro group) Group, amino group, imine group, etc.). These substituents may further have a substituent. Examples of the alkoxy group of R ^{1 to} R ⁷ include C 1-20 alkoxy groups such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a tert-butoxy group, and the above R ^{1 to} R ⁷ . Examples of the allyloxy group include C6-C20 allyloxy groups such as a phenoxy group and a naphthoxy group. Further, as the X ¹ hydrogen, lithium, sodium, potassium and the like, preferably hydrogen or sodium.

Examples of the divalent aliphatic hydrocarbon group which may 0 to 20 carbon atoms optionally having a substituent of the R ^8, methylene, difluoromethylene, ethylene, tetrafluoroethylene, etc., and the substituent of the R ⁸ Examples of the divalent aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a 1,2-phenylene group, 1,4-phenylene group, 4-methyl-1,2-phenylene group, 4-methoxy- 1,2-phenylene group, 4-t-butyl-1,2-phenylene group and the like, and an aliphatic group having 1 to 20 carbon atoms which may have a substituent of the above R ⁹ , R ¹⁰ and R ¹¹ Examples of the hydrocarbon group include a trifluoromethyl group and a pentafluoroethyl group, and examples of the aromatic hydrocarbon group having 6 to 20 carbon atoms that may have a substituent of the above R ⁹ , R ¹⁰ and R ^11. Is pentafluorophenyl Groups and the like. The substituents of these aliphatic hydrocarbon groups or aromatic hydrocarbon groups are the same as the substituents of the aliphatic hydrocarbon group or aromatic hydrocarbon group in R ^{1 to} R ⁷ described above.

In addition, the metal compound (A2) constituting the component A contained in the vinyl ester monomer polymerization catalyst composition of the present invention,
Formula (XIV):
MX ² _a L _b (XIV)
It is represented by In the formula, M represents an element selected from Groups 3 to 11 of the periodic table. For example, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Y, Zr, Nb, Mo, Examples include Ru, Rh, Pd, Ag, La, Hf, Ta, W, Re, OS, Ir, Pt, Au, and the like, and Fe, Co, Rh, or Pd is preferable. X ² represents hydrogen, an optionally substituted aliphatic hydrocarbon group having 1 to 20 carbon atoms, an optionally substituted aromatic hydrocarbon group having 6 to 20 carbon atoms, or a halogen atom. Represents. Specific examples of the aliphatic hydrocarbon group and having a substituent of optionally C6-20 aromatic hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, in R ¹ to R ⁷ are the same as specific examples of these groups, the substituents of these groups are also the same as the substituent groups in R ¹ to R ^7. L represents a compound capable of coordinating with a metal, such as trialkylphosphine such as tributylphosphine, arylphosphine such as triphenylphosphine, acetonitrile, benzonitrile, 1,5-cyclooctadiene, pyridine, 2,2 ′. -Bipyridine, 1,10-phenanthroline, carbonyl and the like. b shows the number of L, and is specifically 0-8. X ² is particularly preferably a halogen atom or a methyl group. Furthermore a is a number of ^{X 2,} in particular 1 to 6. When the number of X ² is 2 to 6, each X ² may be the same as or different from each other. Therefore, the compound represented by the formula (XIV) may be a compound composed of different X ² such as PdMeCl (PPh ₃ ) ₂ .

  Furthermore, in Component A obtained by the reaction of the compound having a fluorine-containing hydroxyl group and the metal compound, the bond between the fluorine-containing compound having a hydroxyl group (A1) and the metal is not particularly limited, but at least one is a covalent bond, It represents either an ionic bond or a coordinate bond.

^{R 8} in the formula (XV) has the same meaning as ^{R 8} in formula (XII) or (XIII), specific examples are also the same. Similarly M and ^{X 2} in formula (XVI) has the same meaning as M and ^{X 2} in formula (XIV), and have the same specific examples. (XVI) ^R 1 ^{~R 5} and ^R 12 ^{to R 15} in is the same as ^R 1 to R ⁷ in formula (I) ~ (XI), is the same as specific examples thereof. X ³ represents oxygen or a hydroxyl group.

Examples of the metal compound represented by Component A include compounds (XVII), (XVIII), (XIX), (XX), (XXI), (XXII) and the like represented by the following structure.

  The utilization form of the polymerization catalyst composition of the present invention includes a method of using it alone and a method of using it supported on an inorganic or organic carrier. Examples of the inorganic carrier include inorganic substances, metal oxides and halides, and examples thereof include activated carbon, alumina, silica, alumina-silica, zeolite, magnesium chloride, magnesium oxide, calcium chloride, and copper chloride. Furthermore, what can become an inorganic support | carrier by reaction can also be used. For example, a reaction product of metal magnesium and alcohol can be used.

  Examples of the organic carrier include a polymer compound insoluble in an organic solvent and an ion exchange resin. For example, polystyrene beads, cyclodextrin, Amberlyst, Nafion, Dowex, Sephadex, silica gel and the like can be mentioned.

  As a method for supporting the polymerization catalyst composition on an inorganic or organic carrier, a method generally used in the catalyst production technical field can be used. For example, a method of co-grinding the polymerization catalyst composition and an inorganic carrier in a ball mill or a vibration mill under an inert gas atmosphere, or a dry support after immersing an inorganic or organic carrier in a solution of the polymerization catalyst composition And a method of chemically binding a ligand of the polymerization catalyst composition to an organic carrier. The amount of the polymerization catalyst composition supported on the inorganic or organic carrier is not particularly limited, but is preferably about 0.001 to 30 wt%.

Component B has (a) an atomic number of 3 or more and at least one element selected from Group 1, 2, 11, 12 and 13 elements of the periodic table, and (b) a substituent. Three groups consisting of an aliphatic hydrocarbon group having 1 to 20 carbon atoms and / or an aromatic hydrocarbon group having 6 to 40 carbon atoms which may have a substituent and (c) a perchloric acid group. A compound having an element and / or a group selected from at least one of at least two of them is included. Examples of the optionally substituted aliphatic hydrocarbon group having 1 to 20 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert group -Linear or branched chain such as butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, cycloheptyl group Or a cyclic | annular aliphatic hydrocarbon group is mentioned. Examples of the aromatic hydrocarbon group having 6 to 40 carbon atoms which may have a substituent include a phenyl group, a naphthyl group, a biphenyl group, an anthryl group, a phenanthryl group, an indenyl group, a fluorenyl group, and an azulenyl group. The substituents of these groups, aliphatic hydrocarbon group having 1 to 20 carbon atoms of the R ¹ to R ^7, aromatic hydrocarbon group having 6 to 20 carbon atoms, a methoxy group, an ethoxy group, a propoxy group , Butoxy group, alkoxy group such as tert-butoxy group, allyloxy group such as phenoxy group, naphthoxy group, halogen atom (F, Cl, Br, I), acetoxy group, nitro group, sulfonic acid group, carbonyl group, amino group And the like. These substituents may further have a substituent.

  Examples of the compound contained in Component B include alkyl lithium, alkyl sodium, alkyl magnesium, trifluoromethane sulfonate, perchlorate, alkyl zinc, alkyl boron, borate, and alkyl aluminum. Specific examples include methyl lithium, butyl lithium, phenyl lithium, butyl sodium, butyl ethyl magnesium, methyl magnesium bromide, ethyl magnesium bromide, butyl magnesium bromide, phenyl magnesium bromide, methyl magnesium chloride, ethyl magnesium chloride, chloride. Butyl magnesium, phenyl magnesium chloride, silver trifluoromethanesulfonate, silver perchlorate, triphenylmethyl perchlorate, diethyl zinc, silver borofluoride, trispentafluorophenyl boron, tris (trifluoromethyl) boron, tetrakis pentafluorophenyl Triphenylmethyl borate, tetrakis [3,5-di (trifluoromethyl) phenyl] triphenylmethyl borate, tetrakis [3,5-di (trifluoromethyl) pheny ] Sodium borate, trimethylaluminum, triethylaluminum, triisopropylaluminum, triisobutylaluminum, dimethylaluminum chloride, diethylaluminum chloride, ethylaluminum dichloride, ethylaluminum sesquichloride, diisobutylaluminum methoxide, diisobutylaluminum ethoxide, diisobutylaluminum isopropoxy , Diethylaluminum ethoxide, dibutylaluminum butoxide, ethylaluminum sesquiethoxide, butylaluminum sesquibutoxide, diisopropylaluminum hydride, methylaluminum bis (2,6-ditert-butylphenoxide), methylaluminum bis (2,6- Di tert-butyl-4- Tilphenoxide), isobutylaluminum bis (2,6-ditert-butylphenoxide), isobutylaluminum bis (2,6-ditert-butyl-4-methylphenoxide), methylaluminum bis {2- (N-phenylimino) Phenoxide}, isobutylaluminum bis {2- (N-phenylimino) phenoxide}, diethylaluminum {2- (N-phenylimino) phenoxide}, dimethylaluminum (N, N'-diisopropylacetamidinate), dimethylaluminum ( N, N'-dicyclohexylacetamidinate), dimethylgallium (N, N'-diisopropylacetamidinate), dimethylgallium (N, N'-dicyclohexylacetamidinate), through oxygen and nitrogen atoms 2 or more And aluminoxane compounds to which aluminum is bonded. Of these, trimethylaluminum, triethylaluminum, triisobutylaluminum, diethylaluminum chloride, ethylaluminum dichloridealuminoxane compound and the like are preferable. Component B can be used by mixing one or more of these compounds.

  A typical vinyl ester monomer used in the present invention is vinyl acetate. However, in this invention, in addition to vinyl acetate, a C3-20 vinyl ester monomer can be used. For example, vinyl formate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl 2-ethylhexanoate, vinyl benzoate and the like can be mentioned. Moreover, these may be individual or may combine 2 or more types. A monomer that can be copolymerized with a vinyl ester monomer at the time of polymerization of the vinyl ester monomer using the supported catalyst composition for polymerization of the present invention, for example, an α-olefin such as ethylene, propylene, and isobutene, acrylic acid, methacryl Unsaturated acids such as acids, crotonic acid, maleic acid, itaconic acid, maleic anhydride or their salts or mono- or dialkyl esters, acrylonitrile, methacrylonitriles, acrylamide, methacrylamides, vinyl ethers, vinyl chloride, vinylidene chloride, Styrene, α-methylstyrene, butadiene, isoprene, 1,5-hexadiene, cyclopentadiene, vinyl norbornene, norbornene, norbornadiene, vinyl sulfonic acid or a salt thereof can be present in a small amount.

  The polymerization conditions are not particularly limited, but it is preferable to use a mixed solution of a vinyl ester monomer and an inert solvent. As the inert solvent, any solvent can be used as long as it does not inhibit the polymerization. In particular, an aliphatic hydrocarbon having 4 to 20 carbon atoms, such as isobutane, pentane, hexane, heptane, cyclohexane and the like, is aromatic. Hydrocarbons such as toluene and xylene, halogenated aliphatic hydrocarbons having 1 to 20 carbon atoms such as chloroform, methylene chloride, hydrogen tetrachloride, dibromoethane, tetrachloroethane, halogenated aromatic hydrocarbons such as chlorobenzene, di Chlorobenzene and the like, aliphatic esters having 3 to 20 carbon atoms such as methyl acetate, ethyl acetate, 2-ethylhexyl acetate, phenyl acetate and ethyl hexanoate, or aromatic esters such as methyl benzoate and ethyl benzoate Is appropriate.

  In the practice of the present invention, component A is used in an amount corresponding to 0.001 to 2.5 moles of metal atoms of Group 3 to Group 11 of the periodic table per liter of a mixed solution containing a vinyl ester monomer and an inert solvent. It is preferable to use a higher concentration depending on the conditions.

  Component B can be appropriately changed in concentration depending on the type of component A or the like, but is usually 0.001 to 50 moles or 1 to 2, 1 in the periodic table per 1 L of a mixed solution containing a vinyl ester monomer and an inert solvent. Used in a concentration of 0.001 to 50 mol of metal atoms of group 11, 12 or 13. The molar ratio of component B / component A of the catalyst composition is not particularly limited, but is usually 0 to 10,000, preferably 0 to 5000, and more preferably 0.1 to 1000.

  The polymerization operation in the main polymerization can be performed not only in a single-stage polymerization performed under normal single polymerization conditions but also in a multi-stage polymerization performed under a plurality of polymerization conditions.

  Although the polymerization conditions in this invention are not specifically limited, Usually, it is -100 degreeC-200 degreeC, Preferably it is -20 degreeC-100 degreeC.

  The PVA of the present invention is produced by saponifying a vinyl ester polymer obtained by polymerization, but the saponification method and its conditions are not particularly limited, and an alcohol solution of the vinyl ester polymer is treated with sodium hydroxide, water. Saponification can be performed by a known method using an alkali such as potassium oxide as a catalyst.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples. In addition, the measuring method used for the Example and the comparative example is as follows.

(Identification of components A1 and A)
¹ H-NMR was measured using a nuclear magnetic resonance apparatus (JNM-LAMBDA-300, manufactured by JEOL).

(Syndiotacticity (double children))
Polyvinyl acetate was converted into PVA by alkali saponification according to a conventional method, and the triplet (mm / mr / rr) was measured by ¹ H-NMR measurement using a nuclear magnetic resonance apparatus (manufactured by JEOL, JNM-LAMBDA-400). The ratio (%) was obtained, and syndiotacticity (doublet) (r) (%) was calculated from the following formula.
Syndiotacticity (doublet) (r) = rr + (mr / 2)

(Molecular weight of polymer)
A gel permeation chromatograph (manufactured by Tosoh Corp., RI-8020) equipped with a column (manufactured by Tosoh Corp., TSKgelGMHHR-M and TSKgelG2000HHR) and a differential refractometer (manufactured by Tosoh Corp.), 40 ° C, tetrahydrofuran In the solvent, the weight average molecular weight (Mw) and the degree of dispersion [weight average molecular weight (Mw) / number average molecular weight (Mn)] of the vinyl ester polymer were determined in terms of polystyrene.

Synthesis example 1
[Preparation of component A1]
Synthesis of 2- (2-amino-5-methylphenyl) -1,1,1,3,3,3-hexafluoropropan-2-ol p-Toluidine (7.01 g, 65.4 mmol) was added to an argon-substituted Schlenk flask. ), P-toluenesulfonic acid (0.263 g) and hexafluoroacetone (10 ml, 71.8 mmol) were added, and the mixture was heated to reflux for 2 hours. The reaction solution was returned to room temperature, and the produced white crystals were separated by filtration and dried to obtain the title compound (yield: 7.21 g, yield: 40%).
¹ H-NMR (CD ₃ Cl, 300 MHz) 7.37-6.94 (m, 3H), 4.02 (br, 3H), 2.35 (s, 3H)

シュレンクフラスコに２−ヒドロキシ−５−メチル−１，３−ベンゼンジカルボキシアルデヒド（３１５ｍｇ，１．９１ｍｍｏｌ）、２−（２−アミノー５−メチルフェニル）−１，１，１，３，３，３−ヘキサフルオロプロパンー２−オール（５４５ｍｇ，２．００ｍｍｏｌ）、ｐ−トルイジン（２１４ｍｇ、２．００ｍｍｏｌ）およびエタノール（１０ｍｌ）を加えて、室温で５時間撹拌した。反応溶液を濾別後、エーテルで洗浄、乾燥して標記の化合物を得た（収量：７４７ｍｇ，収率：７４％）。
^１Ｈ−ＮＭＲ（ＣＤ_３Ｃｌ，３００ＭＨｚ）９．０６（ｓ、２Ｈ），８．６１（ｓ、１Ｈ）、８．６０（ｓ、１Ｈ），７．８０−７．１２（ｍ、５Ｈ）、６．８０（ｄ、２Ｈ）、６．０８（ｓ、２Ｈ）、（ｍ、９Ｈ） Synthesis example 2
[Preparation of component A1]
Synthesis of compound (XXIII)

In a Schlenk flask, 2-hydroxy-5-methyl-1,3-benzenedicarboxaldehyde (315 mg, 1.91 mmol), 2- (2-amino-5-methylphenyl) -1,1,1,3,3,3 -Hexafluoropropan-2-ol (545 mg, 2.00 mmol), p-toluidine (214 mg, 2.00 mmol) and ethanol (10 ml) were added and stirred at room temperature for 5 hours. The reaction solution was filtered off, washed with ether and dried to give the title compound (yield: 747 mg, yield: 74%).
¹ H-NMR (CD ₃ Cl, 300 MHz) 9.06 (s, 2H), 8.61 (s, 1H), 8.60 (s, 1H), 7.80-7.12 (m, 5H) 6.80 (d, 2H), 6.08 (s, 2H), (m, 9H)

シュレンクフラスコに化合物（ＸＸＩＩＩ）（２５４ｍｇ，０．５０ｍｍｏｌ）、トルエン（１０ｍｌ）およびジクロロビス（ベンゾニトリル）パラジウム（７６７ｍｇ，１．０ｍｏｌ）を加えて、室温で１２時間撹拌した。溶媒を留去後、塩化メチレンに溶解し、セライト濾過を行った。濾液から塩化メチレンを留去して標記の錯体を得た。（収量：４５５ｍｇ、収率６６．３％）。
^１Ｈ−ＮＭＲ（ＣＤ_３Ｃｌ，３００ＭＨｚ）：δ８．９８（ｓ、１Ｈ）、７．８４−６．３６（ｍ、１０Ｈ）、２．３６（ｓ、３Ｈ）、２．２７（ｓ、３Ｈ）、２．２３（ｓ、３Ｈ） Synthesis example 3
[Preparation of component A]
Synthesis of compound (XVII)

Compound (XXIII) (254 mg, 0.50 mmol), toluene (10 ml) and dichlorobis (benzonitrile) palladium (767 mg, 1.0 mol) were added to the Schlenk flask, and the mixture was stirred at room temperature for 12 hours. After the solvent was distilled off, the residue was dissolved in methylene chloride and filtered through celite. Methylene chloride was distilled off from the filtrate to obtain the title complex. (Yield: 455 mg, 66.3% yield).
¹ H-NMR (CD ₃ Cl, 300 MHz): δ 8.98 (s, 1H), 7.84-6.36 (m, 10H), 2.36 (s, 3H), 2.27 (s, 3H) ), 2.23 (s, 3H)

アルゴン置換したシュレンクフラスコに２−ヒドロキシ−５−メチル−１，３−ベンゼンジカルボキシアルデヒド（１．０１ｇ，６．７０ｍｍｏｌ）、２，６−ジイソプロピルアニリン（３．５７ｇ，２０．１２ｍｍｏｌ）、エタノール（１５ｍｌ）および数滴の氷酢酸を加えて、３０分間加熱還流した。反応溶液を濃縮し、−２０℃で再結晶して標記の化合物を得た（収量：２．３１ｇ，収率：７１．４％）。
^１Ｈ−ＮＭＲ（ＣＤ_３Ｃｌ，３００ＭＨｚ）１３．４３（ｓ，１Ｈ）、８．１７−８．５９（ｂｒ，２Ｈ）、７．２３（ｓ，８Ｈ）、３．０３−３．１２（ｍ，４Ｈ），２．４８（ｓ，３Ｈ）、１．２７（ｓ，２４Ｈ） Synthesis example 4
[Preparation of component A1]
Synthesis of compound (XXIV)

In a Schlenk flask substituted with argon, 2-hydroxy-5-methyl-1,3-benzenedicarboxaldehyde (1.01 g, 6.70 mmol), 2,6-diisopropylaniline (3.57 g, 20.12 mmol), ethanol ( 15 ml) and a few drops of glacial acetic acid were added and heated to reflux for 30 minutes. The reaction solution was concentrated and recrystallized at −20 ° C. to obtain the title compound (yield: 2.31 g, yield: 71.4%).
¹ H-NMR (CD ₃ Cl, 300 MHz) 13.43 (s, 1H), 8.17-8.59 (br, 2H), 7.23 (s, 8H), 3.03-3.12 ( m, 4H), 2.48 (s, 3H), 1.27 (s, 24H)

シュレンクフラスコに化合物（ＸＸＩＶ）（４８３ｍｇ，０．５０ｍｍｏｌ）、トルエン（１０ｍｌ）およびジクロロビス（ベンゾニトリル）パラジウム（７６７ｍｇ，１．０ｍｍｏｌ）を加えて、室温で１２時間撹拌した。溶媒を留去後、塩化メチレンに溶解し、セライト濾過を行った。濾液から塩化メチレンを留去して標記の錯体を得た。（収量：４６３ｍｇ、７０．２％）。
^１Ｈ−ＮＭＲ（ＣＤ_３Ｃｌ，３００ＭＨｚ）７．５５−７．１０（ｍ、１０Ｈ）、３．５３−３．０８（ｍ、４Ｈ）、２．３３（ｓ、３Ｈ）、１．４８（ｄ、１２Ｈ）、１．２９（ｓ、１２Ｈ） Synthesis example 5
[Preparation of component A]
Synthesis of compound (XXV)

Compound (XXIV) (483 mg, 0.50 mmol), toluene (10 ml) and dichlorobis (benzonitrile) palladium (767 mg, 1.0 mmol) were added to the Schlenk flask and stirred at room temperature for 12 hours. After the solvent was distilled off, the residue was dissolved in methylene chloride and filtered through celite. Methylene chloride was distilled off from the filtrate to obtain the title complex. (Yield: 463 mg, 70.2%).
¹ H-NMR (CD ₃ Cl, 300 MHz) 7.55-7.10 (m, 10H), 3.53-3.08 (m, 4H), 2.33 (s, 3H), 1.48 ( d, 12H), 1.29 (s, 12H)

Example 1
Polymerization of vinyl acetate using Compound (XVII) Toluene (0.01 L) was charged into an argon-substituted 0.1 L Schlenk flask, and Compound (XVII) (34.3 mg, 0.05 mmol) and methylaluminoxane (aluminum atom) 2.00 mmol) was added, vinyl acetate (10 mL, 108 mmol) was further added, and the mixture was stirred at room temperature for 24 hours. After 24 hours, the reaction solution was poured into 0.1 L of a 0.1 M hydrochloric acid aqueous solution, and the product was extracted with chloroform to obtain polyvinyl acetate (yield: 0.14 g, yield: 1.5%). Mw = 5200; Mw / Mn = 1.42. r dyad: 33 + 50/2 = 58.0%

Example 2
Polymerization of vinyl acetate using Compound (XVII) Toluene (0.01 L) was charged into an argon-substituted 0.1 L Schlenk flask, and Compound (XVII) (34.3 mg, 0.05 mmol) and methylaluminoxane (aluminum atom) 15.0 mmol) was added, vinyl acetate (10 mL, 108 mmol) was further added, and the mixture was stirred at room temperature for 24 hours. After 24 hours, the reaction solution was put into 0.1 L of 0.1 M hydrochloric acid aqueous solution, and the product was extracted with chloroform to obtain polyvinyl acetate (yield: 4.32 g, yield: 46.3%). Mw = 7300; Mw / Mn = 2.15. r dyad = 56.4%

Example 3
Polymerization of vinyl acetate using Compound (XX) Toluene (0.01 L) was charged into an argon-substituted 0.1 L Schlenk flask, and Compound (XXIII) (25.4 mg, 0.05 mmol) and FeCl ₂ (6. 3 mg, 0.05 mmol) was added and stirred at room temperature for 2 hours. Methylaluminoxane (2.00 mmol in terms of aluminum atom) was added thereto, vinyl acetate (0.01 L, 108 mmol) was further added, and the mixture was stirred at room temperature for 24 hours. After 24 hours, the reaction solution was put into 0.1 L of a 0.1 M hydrochloric acid aqueous solution, and the product was extracted with chloroform to obtain polyvinyl acetate (yield: 0.10 g, yield: 1.1%). Mw = 2,600; Mw / Mn = 1.07. r dyad = 57.0%

Example 4
Polymerization of vinyl acetate using compound (XXI) Toluene (0.01 L) was charged into an argon-substituted 0.1 L Schlenk flask, and compound (XXIII) (25.4 mg, 0.05 mmol) and CoCl ₂ (6. 5 mg, 0.05 mmol) was added and stirred at room temperature for 2 hours. Methylaluminoxane (2.00 mmol in terms of aluminum atom) was added thereto, vinyl acetate (0.01 L, 108 mmol) was further added, and the mixture was stirred at room temperature for 24 hours. After 24 hours, the reaction solution was put into 0.1 L of 0.1 M aqueous hydrochloric acid, and the product was extracted with chloroform to obtain polyvinyl acetate (yield: 0.12 g, yield: 1.3%). Mw = 3,600; Mw / Mn = 1.25. r dyad = 57.2%

Example 5
Polymerization of vinyl acetate using compound (XXII) Toluene (0.01 L) was charged into a 0.1 L Schlenk flask substituted with argon, and compound (XXIII) (25.4 mg, 0.05 mmol) and RhCl ₃ (10. 5 mg, 0.05 mmol) was added and stirred at room temperature for 2 hours. Methylaluminoxane (2.00 mmol in terms of aluminum atom) was added thereto, vinyl acetate (0.01 L, 108 mmol) was further added, and the mixture was stirred at room temperature for 24 hours. After 24 hours, the reaction solution was poured into 0.1 L of a 0.1 M hydrochloric acid aqueous solution, and the product was extracted with chloroform to obtain polyvinyl acetate (yield: 0.14 g, yield: 1.5%). Mw = 4,600; Mw / Mn = 1.65. r dyad = 57.3%

Comparative Example 1
Polymerization of vinyl acetate using compound (XXV) Toluene (0.01 L) was charged into an argon-substituted 0.1 L Schlenk flask, and compound (XXV) (33.0 mg, 0.05 mmol) and methylaluminoxane (aluminum atom) 2.00 mmol) was added, vinyl acetate (0.01 L, 108 mmol) was further added, and the mixture was stirred at room temperature for 24 hours. After 24 hours, the reaction solution was put into 0.1 L of a 0.1 M hydrochloric acid aqueous solution, and the product was extracted with chloroform to obtain polyvinyl acetate (yield: 0.17 g, yield: 1.8%). Mw = 5,000; Mw / Mn = 1.50. r dyad = 53.0%

  As is clear from the comparison between Examples 1 to 5 and Comparative Example 1, it can be seen that when the polymerization catalyst composition of the present invention is used, a polymer having high syndiotacticity can be produced under mild conditions.

Claims (12)

A catalyst composition for syndiotactic polymerization of vinyl ester monomers comprising the following formulas (I), (II), (III), (IV), (V), (VI), (VII), (VIII) , (IX), (X) and (XI):

[In formulas (I) to (XI), R ^{1 to} R ⁷ are each hydrogen, an optionally substituted aliphatic hydrocarbon group having 1 to 20 carbon atoms, or an optionally substituted carbon. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms or an allyloxy group having 6 to 20 carbon atoms, X ¹ represents an element of Group ¹ of the periodic table, and Y ¹ and Y ² Are the following formulas (XII) or (XIII):

(In formulas (XII) to (XIII), R ⁸ may have a divalent aliphatic hydrocarbon group having 0 to 20 carbon atoms which may have a substituent or a substituent having 6 to 20 carbon atoms. Each of R ⁹ , R ¹⁰ and R ¹¹ is hydrogen, fluorine, chlorine, an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, or Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent. At least one compound (A1) selected from the group consisting of fluorine-containing compounds having a hydroxyl group represented by:
Formula (XIV):
MX ² _a L _b (XIV)
(In the formula (XIV), M represents an element selected from Groups 3 to 11 of the periodic table, and X ² is hydrogen and an aliphatic hydrocarbon group having 1 to 20 carbon atoms which may have a substituent. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent, or a halogen atom, a representing the number of X ² represents 1 to 6, and when a is 2 to 6, X ² May be the same as or different from each other, L represents a compound capable of coordinating bond to a metal, and b representing the number of L represents 0 to 8). The said catalyst composition for polymerization containing the component A containing the metal compound obtained by reaction with an at least 1 sort (s) of compound (A2). At least one of Y ¹ and Y ² of component A1 is represented by the following formula (XV):

(In Formula (XV), R ⁸ is a divalent aliphatic hydrocarbon group having 0 to 20 carbon atoms which may have a substituent, or a divalent aliphatic group having 6 to 20 carbon atoms which may have a substituent. The polymerization catalyst composition according to claim 1, wherein the polymerization catalyst composition is a group represented by: Component A is represented by the following formula (XVI):

(In Formula (XVI), R ^{1 to} R ⁵ and R ^{12 to} R ¹⁵ may each have hydrogen, a C 1-20 aliphatic hydrocarbon group that may have a substituent, or a substituent. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an allyloxy group having 6 to 20 carbon atoms, and X ² is hydrogen and may have a substituent. Represents an aliphatic hydrocarbon group of -20, an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent, or a halogen atom, a representing the number of X ² represents 1 to 6, and a represents 2 to 6, X ² may be the same or different from each other, M represents an element selected from Groups 3 to 11 of the periodic table, and X ³ represents oxygen or a hydroxyl group. The at least 1 type of metal compound chosen from the group which consists of a compound of Claim 1 or 2 If catalyst composition.   The polymerization catalyst composition according to any one of claims 1 to 3, wherein M is iron, cobalt, rhodium or palladium. (A) an atomic number of 3 or more and at least one element selected from elements of Groups 1, 2, 11, 12 and 13 of the periodic table, (b) carbon number which may have a substituent 1 to 20 aliphatic hydrocarbon groups and / or an aromatic hydrocarbon group having 6 to 40 carbon atoms which may have a substituent and (c) a perchloric acid group, at least 2 of 3 groups The polymerization catalyst composition according to any one of claims 1 to 4, further comprising Component B containing a compound having an element and / or a group selected from one or more groups.   The catalyst composition for polymerization according to claim 4, wherein Component B is an organolithium compound, organomagnesium compound, trifluoromethanesulfonate, perchlorate, organozinc compound, organoboron compound, borate or organoaluminum compound. object.   The polymerization catalyst composition according to any one of claims 1 to 6, wherein the resulting polymer has a syndiotacticity of 55% or more in racemo diads (r). Formula (XVI):

(In Formula (XVI), R ^{1 to} R ⁵ and R ^{12 to} R ¹⁵ may each have hydrogen, a C 1-20 aliphatic hydrocarbon group that may have a substituent, or a substituent. Represents an aromatic hydrocarbon group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an allyloxy group having 6 to 20 carbon atoms, and X ² is hydrogen and may have a substituent. Represents an aliphatic hydrocarbon group of -20, an aromatic hydrocarbon group having 6 to 20 carbon atoms which may have a substituent, or a halogen atom, a representing the number of X ² represents 1 to 6, and a represents 2 to 6, X ² may be the same or different from each other, M represents an element selected from Groups 3 to 11 of the periodic table, and X ³ represents oxygen or a hydroxyl group. Compound.   Use of the polymerization catalyst composition according to any one of claims 1 to 7 for syndiotactic polymerization of a vinyl ester monomer.   Use of the vinyl ester monomer according to claim 9 for syndiotactic polymerization according to claim 9, wherein the vinyl ester monomer is vinyl acetate.   The use for syndiotactic polymerization of a vinyl ester monomer according to claim 9 or 10, wherein the syndiotacticity of the polymer is 55% or more by racemo diad (r).   A method for producing polyvinyl acetate or a copolymer containing vinyl acetate by syndiotactic polymerization of a vinyl ester monomer in the presence of the polymerization catalyst composition according to any one of claims 1 to 7, comprising: The above production method, wherein the syndiotacticity is 55% or more by racemo diad (r).