JPH09324039A - Preparation of poly-1,4-phenylene ether - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for preparing a poly-1,4-phenylene ether which does not have a C-C bond structure, has such a regulated structure as to be reduced in the branching at the o-position, and exhibits an m.p. SOLUTION: A starting compd. represented by the formula (wherein (m) is the number of average units and 1<m) is polymerized in the presence of an oxidizing agent and a transition metal complex catalyst therein the number of group 4-11 transition metal atoms per tridentate ligand is 1 or more when the ligand atom is a nitrogen atom, a phosphorus atom, an oxygen atom, or a sulfur atom.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a method for producing poly-1,4-phenylene ether.

[0002]

2. Description of the Related Art Oxidative polymerization using a transition metal complex catalyst of 2,6-dimethylphenol (for example, see JP-B-63-663).
No. 091, JP-A-59-131627, and many others. )
(2,6-dimethylphenylene ether) (hereinafter referred to as PP
Sometimes abbreviated as E. ) Are known to be useful resins. However, PPE has a disadvantage that it is difficult to melt-mold PPE alone because a methyl group substituted by an aromatic ring is susceptible to oxidative deterioration, and is generally positioned as a general-purpose engineering plastic as a polymer alloy with polystyrene. .

On the other hand, poly-1,4-phenylene ether (hereinafter sometimes abbreviated as PAO) is available from Europ. Polym.
J., 4,275 (1968).
° C (glass transition temperature is 83 ° C), which exceeds the melting point of polyphenylene sulfide (285 ° C), which is generally called super engineering plastic, and has the second highest melting point of polyetheretherketone (334 ° C). Its usefulness as a heat-resistant resin is extremely large.

As a method for producing PAO, Europ. Polym.
J., 4,275 (1968) describes the polymerization of sodium salt of p-bromophenol in the presence of a copper catalyst.
There is a problem that the reaction temperature needs to be as high as 200 ° C. and a salt equivalent to the reaction amount is formed. JP-A-59-
Japanese Patent No. 56426 describes a method for producing PAO by electrolytic oxidation polymerization of phenol, but mass production was difficult because the amount of polymer produced per unit time is governed by the surface area of the electrode. In addition, Japanese Patent Publication No.
No. 918 proposes a method of irradiating 4-phenoxyphenol with light of a specific wavelength in the presence of a photosensitizer. However, phenol is by-produced as polymerization proceeds.
In addition, there is a problem in that mass production is difficult due to the method using light irradiation. Further, Japanese Patent Publication No. 44-28917 proposes a method of heating 4-phenoxyphenol to a temperature at which phenol is distilled, but it requires a high temperature and has a problem that phenol is by-produced. Was.

As a method for solving these problems, an oxidative polymerization method using a transition metal complex catalyst is an excellent method because the reaction temperature is relatively low and the by-product to be eliminated is water. As examples of the oxidative polymerization method using a phenolic transition metal complex catalyst, Japanese Patent Publication No. 36-18692, Industrial Chemistry Magazine, Vol. 72, No. 10, 106 (1969), and Japanese Patent Publication No. Sho 4
However, these methods have a problem that an ortho-position branch or a CC bond structure is generated.

Here, the ortho-position branching means that the benzene ring in the phenol polymer has a 1,2,4-trisubstituted benzene structure, which disrupts the originally desired chain of the 1,4-disubstituted benzene structure. Structure. In addition, the CC bond structure indicates that polymerization of phenol does not occur in the reaction between an oxygen atom and a benzene ring but occurs in a reaction between benzene rings, resulting in a biphenyl structure. When the ortho-branching and the CC bond structure increase, the melting point decreases, and eventually PAO becomes an amorphous resin having no melting point, and loses its usefulness as an ultra-high heat-resistant resin due to its high melting point.

In Japanese Patent Publication No. 36-18692 and Industrial Chemistry Magazine, Vol. 72, No. 10, 106 (1969), the reaction of phenol at the ortho position in catalyzed oxidative polymerization of tertiary amine and cuprous salt is described. It has been proposed to use tertiary amines with bulky substituents (such as 2,6-dimethylpyridine etc.) in order to hinder the reaction. However, even the polymer obtained by this method has a CC bond structure and does not sufficiently suppress the ortho-position branching, and cannot be called PAO because it is an amorphous resin in which a melting point is not observed. Was.

On the other hand, Tetrahedron, 23, 2253 (1967)
Phenoxyphenol with cuprous salt and N, N, N ',
Although an example is shown in which oxidative polymerization is carried out using an N′-tetraethylethylenediamine catalyst, the polymer obtained by this method also has many ortho-position branches and no melting point was observed.

[0009]

As described above, in the oxidative polymerization method using a transition metal complex catalyst at present, a large number of ortho-position branches and CC bonds are formed, and a useful polymer has not been obtained. Therefore, the current problem is to produce PAO that can exhibit a melting point. That is, an object of the present invention is to show a controlled, melting point of a structure in which a CC bond structure is not generated and the number of ortho-position branches is small.
An object of the present invention is to provide a method for producing poly-1,4-phenylene ether.

[0010]

Under these circumstances, the present inventors have conducted intensive studies to achieve the above object, and as a result, have determined that a specific raw material can be used in the presence of a specific transition metal complex catalyst. The inventors have found an oxidative polymerization method to be used, and have completed the present invention.

That is, the present invention provides a transition metal having one or more Group 4 to 11 transition metal atoms per tridentate ligand whose coordination atom is a nitrogen atom, a phosphorus atom, an oxygen atom or a sulfur atom. The present invention relates to a method for producing poly-1,4-phenylene ether by polymerizing a raw material represented by the following structural formula in the presence of an oxidizing agent using a complex catalyst. (In the formula, m represents the number average unit number, and 1 <m.) Next, the present invention will be described in detail.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

(1) Transition Metal Complex Catalyst The transition metal complex catalyst used in the present invention is a group 4 to 11 transition per one tridentate ligand whose coordination atom is a nitrogen atom, a phosphorus atom, an oxygen atom or a sulfur atom. It is a transition metal complex catalyst having one or more metal atoms.

The transition metal atom in the transition metal complex catalyst of the present invention is a transition metal atom of Groups 4 to 11 of the periodic table of elements (IUPAC Inorganic Chemistry Nomenclature Revised Edition 1989). Preferred are transition metal atoms of the first transition element series, and more preferred are vanadium, iron, cobalt, nickel and copper. Especially preferred is vanadium.
The valence of the transition metal can be appropriately selected from those normally existing in nature and used, for example, vanadium has a valence of 3 to 5, cobalt has a valence of 2 or 3, and nickel has a valence of 2. In the case of copper, monovalent or divalent can be used.

The tridentate ligand in the transition metal complex catalyst of the present invention is a tridentate ligand whose coordination atom is a nitrogen atom, a phosphorus atom, an oxygen atom or a sulfur atom. In the present invention, a ligand is defined as a chemical dictionary (1st edition, Tokyo Chemical Dojin, 1989).
Year) describes a molecule or ion that is linked to an atom by a coordination bond. The atoms directly involved in the bond are called coordinating atoms. A tridentate ligand is a ligand having three coordinating atoms. In the transition metal complex catalyst of the present invention, due to such a polydentate ligand, there is no CC bond structure,
An environment around a transition metal atom is obtained, which is suitable for obtaining a polymer having a small ortho-branch.

In the transition metal complex catalyst of the present invention, the ratio of the tridentate ligand to the transition metal atom is one or more transition metal atoms per one tridentate ligand, preferably The number of the transition metal atoms is 1 to 3, and more preferably 1 per one tridentate ligand. When the amount of the transition metal atom is smaller than that of the tridentate ligand, the reaction active site supposed on the transition metal atom may be blocked by the tridentate ligand and the catalytic activity may be lost, which is not preferable. The tridentate ligand used in the present invention may itself be a neutral molecule or an ion. Tridentate ligands preferably used are neutral molecules or 1-3 valent anions.

The tridentate ligand in the transition metal complex catalyst of the present invention is not particularly limited, except that the coordination atom is a tridentate ligand having a nitrogen atom, a phosphorus atom, an oxygen atom or a sulfur atom. Specific examples of such a tridentate ligand include 1,2,3
-Trihydroxypropane, 2-amino-1,3-propanediol, 1,3-diamino-2-propanol, 1,3,5-trihydroxypentane, 3-amino-1,5-pentanediol, 2,4 , 6-heptanetrione, 1-phenyl-1,3,5-hexanetrione, diethylene glycol, dipropylene glycol,
Diethylene glycol monomethyl ether, diethylene glycol diethyl ether, di- (2-mercaptoethyl) thioether, bis (1-diphenylphosphinoethyl) ether, 3,3-diformyl-4-methylphenol, 3-formyl-salicylic acid, diethylenetriamine, 1, 7-dimethyldiethylenetriamine, 1,
7-diethyldiethylenetriamine, 1,7-dipropyldiethylenetriamine, 1,7-diphenyldiethylenetriamine, 1,1,4,7,7-pentamethyldiethylenetriamine, N- (2-hydroxyethyl) ethylenediamine, N-. 2-hydroxyethyl) phenylenediamine, N- (2-hydroxyethyl) -1,3-
Propanediamine, N- (3-hydroxypropyl) ethylenediamine, N- (3-hydroxypropyl)-
N ', N'-diethylethylenediamine, diethanolamine, di-2-propanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N-
Propyldiethanolamine, N-phenyldiethanolamine, di-2-hydroxyethyl thioether, 3
-Glycylamino-1-propanol, methyliminodiacetic acid, di- (2-pyridylmethyl) amine, di- (2-
Pyridylethyl) amine, di- (2-imidazolylmethyl) amine, di- (2-oxazolylmethyl) amine,
Di- (2-thiazolylmethyl) amine, N- (2-pyridylmethylidene) -N- (2-pyridylmethyl) amine, N- (2-furylmethylidene) -N- (2-pyridylmethyl) amine, N- ( 2-Thiophenylmethylidene) -N- (2-pyridylmethyl) amine, 2,2 ':
6 ', 2 "-terpyridine, 3- (2-pyridylmethylimino) -2-butanone, 3- (2-pyridylmethylimino) -2-butanone oxime, 3- (2-pyridylethylimino) -2-butanone Oxime, 3- (2-aminoethylimino) -2-butanone oxime, 3- (2-
Hydroxyethylimino) -2-butanone, 4- (2-
Pyridylmethylimino) -2-pentanone, N-salicylidene- (2-pyridylmethyl) amine, N-salicylidene- (2-pyridylethyl) amine, N-salicylidene-N ′, N′-dimethylethylenediamine, N-salicylidene- N ', N'-diethylethylenediamine, N
-Salicylidene-N ', N'-dipropylethylenediamine, N-salicylidene-N', N'-diphenylethylenediamine, 4- (2-hydroxyethylimino)-
2-pentanone, 4- (3-hydroxypropylimino) -2-pentanone, N-salicylidene-2-hydroxyaniline, N-salicylidene-glycine, tris (2-pyridyl) methane, trispyrazolyl borate, 1,4,7 -Triazacyclononane, etc., or
Examples thereof include anions obtained by removing one or more protons from them.

In the transition metal complex of the present invention, the structure other than the ligand and the transition metal atom is not particularly limited as long as it does not deactivate the catalytic ability. In some cases, the transition metal complex of the present invention requires a counter ion to maintain electrical neutrality. As the counter anion, a conjugate base of Bronsted acid is usually used, and specific examples thereof include fluoride ion, chloride ion, bromide ion, iodide ion, sulfate ion, nitrate ion, carbonate ion,
Perchlorate ion, tetrafluoroborate ion, hexafluorophosphate ion, methanesulfonate ion, trifluoromethanesulfonate ion, toluenesulfonate ion, acetate ion, trifluoroacetate ion, propionate ion, benzoate ion, hydroxylation Examples include a product ion, an oxide ion, a methoxide ion, and an ethoxide ion. As the counter cation, a cation such as an alkali metal or an alkaline earth metal can be appropriately used. In the transition metal complex catalyst of the present invention, a solvent or the like may be coordinated during the raw material of the complex, the synthesis process and / or the oxidative polymerization process.

The coordination atom of the tridentate ligand in the transition metal complex catalyst of the present invention is preferably a nitrogen atom or an oxygen atom.

The transition metal complex catalyst of the present invention is preferably a transition metal complex represented by the following general formula (I). (In the formula, M represents a residue containing a transition metal atom of Groups 4 to 11. R ¹ represents a hydrogen atom, a hydrocarbon group, a substituted hydrocarbon group, or O.
^-, a hydrocarbon oxy group, a substituted hydrocarbon oxy group, an amino group or a substituted amino group, R ² is a hydrogen atom, a hydrocarbon group, substituted hydrocarbon group, a hydrocarbon oxy group, a substituted hydrocarbon oxy group, hydrocarbon An oxycarbonyl group, a substituted hydrocarbon oxycarbonyl group, a cyano group, a nitro group or a halogen atom, R ³ represents a hydrogen atom, a hydrocarbon group, a substituted hydrocarbon group or O ⁻ , and R ⁴ represents a bifunctional carbon atom. It represents a hydrogen group or a substituted hydrocarbon group. R ¹ and R ² and /
Alternatively, R ² and R ³ may form a ring. Y is a counter anion, y is the number of Y, and is appropriately determined by the valence of M. )

In the above general formula (I), M is the fourth to first
It is a residue containing a Group 1 transition metal atom, such as a Group 4-11 transition metal atom or a transition metal atom to which a group such as ＯO 2 is bonded.

The hydrocarbon group in the above general formula (I) is preferably an alkyl group having 1 to 20 carbon atoms, an aralkyl group or an aryl group, specifically, a methyl group, an ethyl group, an n-propyl group or iso. -Propyl group, n-butyl group, iso-butyl group, t-butyl group, pentyl group,
Cyclopentyl, hexyl, cyclohexyl, octyl, decyl, benzyl, phenyl, naphthyl and the like.

The substituted hydrocarbon group in the above general formula (I) is a hydrocarbon group substituted with a halogen atom, an alkoxy group, an amino group, a disubstituted amino group or the like, and specific examples include a trifluoromethyl group, Examples thereof include a 2-t-butyloxyethyl group and a 3-diphenylaminopropyl group.

O ⁻ in the above general formula (I) represents one obtained by removing one proton from the hydroxy group.

The hydrocarbon oxy group in the above general formula (I) is preferably an alkoxy group having 1 to 20 carbon atoms and an aryloxy group, specifically, a methoxy group, an ethoxy group, a propoxy group, a butoxy group and a hexyl group. Examples thereof include an oxy group, an octyloxy group, a phenoxy group and a naphthoxy group.

The substituted hydrocarbon oxy group in the above general formula (I) is a hydrocarbon oxy group substituted with a halogen atom, an alkoxy group, an amino group or the like, and specific examples are:
Examples include a trifluoromethoxy group, a 2-t-butyloxyethoxy group, and a 3-diphenylaminopropoxy group.

The substituted amino group in the above general formula (I) is preferably a substituted amino group having 1 to 20 carbon atoms, specifically, methylamino group, ethylamino group, dimethylamino group, diethylamino group, diamino group and diamino group. Examples thereof include a propylamino group, a dibutylamino group, a methylethylamino group, a methylpropylamino group, a methylbutylamino group, a diphenylamino group and a dinaphthylamino group.

The hydrocarbon oxycarbonyl group in the above general formula (I) is preferably a hydrocarbon oxycarbonyl group having 1 to 20 carbon atoms, specifically, a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, Examples thereof include t-butyloxycarbonyl group and phenoxycarbonyl group.

The substituted hydrocarbon oxycarbonyl group in the above general formula (I) is a hydrocarbon oxycarbonyl group substituted with a halogen atom, an alkoxy group, an amino group or the like, and specific examples include a trifluoromethoxycarbonyl group, 2-t-butyloxyethoxycarbonyl group, 3-
And a diphenylaminopropoxycarbonyl group.

The halogen atom in the above general formula (I) is preferably a chlorine atom, a bromine atom or an iodine atom, more preferably a chlorine atom or a bromine atom.

In the above general formula (I), R ⁴ is a bifunctional hydrocarbon group or a substituted hydrocarbon group, and specific examples thereof include a methylene group, a 1,2-ethylene group and a 1,2-propylene group. , 1,3-propylene group, alkylene group such as 1,4-butylene group, 1,2-cyclopentylene group,
A cycloalkylene group such as a 1,2-cyclohexylene group,
Examples thereof include an arylene group such as a phenylene group and a naphthylene group.

In the above general formula (I), Y is a counter anion, y is the number of Y, and is appropriately determined by the valence of M.

Specific examples of the ligand portion of the transition metal complex represented by the above general formula (I) include 4- (2-hydroxyethylimino) -2-pentanone and 4- (2-hydroxypropylimino). -2-pentanone, 4- (3-hydroxypropylimino) -2-pentanone, 4- (2-
Hydroxycyclohexylimino) -2-pentanone,
4- (2-hydroxyphenylimino) -2-pentanone, 5- (2-hydroxyethylimino) -3-heptanone, 1,1,1,5,5,5-hexafluoro-4-
(2-hydroxyethylimino) -2-pentanone,
1,1,1-trifluoro-4- (2-hydroxyethylimino) -2-pentanone, 4- (2-hydroxyethylimino) -3-methyl-2-pentanone, 4- (2
-Hydroxyethylimino) -3-ethyl-2-pentanone, 4- (2-hydroxyethylimino) -3-propyl-2-pentanone, 4- (2-hydroxyethylimino) -3-phenyl-2-pentanone, 4- (2-hydroxyethylimino) -3-methoxy-2-pentanone, 4- (2-hydroxyethylimino) -3-methoxycarbonyl-2-pentanone, 4- (2-hydroxyethylimino) -3-cyano -2-pentanone, 4-
(2-Hydroxyethylimino) -3-nitro-2-pentanone, 4- (2-hydroxyethylimino) -3-
Chloro-2-pentanone, 3- (2-hydroxyethylimino) -1,3-diphenyl-1-propanone, 4-
(2-Hydroxyethylimino) -2-butanone, 5-
(2-hydroxyethylimino) -3-pentanone, 6
-(2-hydroxyethylimino) -4-hexanone,
5- (2-hydroxyethylimino) -2-methyl-3
-Pentanone, 5- (2-hydroxyethylimino)-
2,2-dimethyl-3-pentanone, 3- (2-hydroxyethylimino) -1-phenyl-1-propanone,
N-salicylidene-2-hydroxyethylamine, N-
Salicylidene-3-hydroxypropylamine, N-salicylidene-2-hydroxyaniline, N- (5-methylsalicylidene) -2-hydroxyaniline, N- (5
-Methoxysalicylidene) -2-hydroxyaniline,
N- (5-nitrosalicylidene) -2-hydroxyaniline, N (3,5-dimethylsalicylidene) 2-hydroxyaniline, N- (3,5-di-t-butylsalicylidene) -2 -Hydroxyaniline, N-salicylidene-
2-hydroxy-5-methylaniline, N-salicylidene-2-hydroxy-5-nitroaniline, 3- (2-
Hydroxyethylimino) propionic acid, 3- (2-hydroxyethylimino) butyric acid, methyl 3- (2-hydroxyethylimino) propionate, ethyl 3- (2-hydroxyethylimino) propionate, 3- (2-hydroxy) Ethylimino) propionic acid amide, N- (2-
(Hydroxyethyl) malonic acid monoethyl ester monoamide, N-salicylideneglycine, N-salicylidene alanine, N-salicylidene valine, N-salicylidene leucine, or the like in which one or more protons are removed Can be mentioned.

Transition metal complex represented by the above general formula (I)
And preferably R¹Is a hydrogen atom, hydrocarbon group,
A substituted hydrocarbon group, a hydrocarbon oxy group or a substituted amino group
R ^TwoIs a hydrogen atom, a hydrocarbon group, a substituted hydrocarbon group,
Rogen atom, R¹And R^TwoTogether, Yoshi
An incense ring may be formed. Also, R^ThreeAs preferably,
A hydrogen atom, a hydrocarbon group or a substituted hydrocarbon group, R^FourWhen
Is an alkylene group, cycloalkylene group, arylene
Groups are preferred. More preferably, R¹Is a methyl group,
Cyl group, n-propyl group, iso-propyl group, t-bu
Cyl group, phenyl group, trifluoromethyl group, methoxy
Group, dimethylamino group, etc., R^TwoIs a methyl group,
Group, n-propyl group, iso-propyl group, t-butyl
Group, phenyl group, trifluoromethyl group, chlorine atom,
R is a bromine atom, etc.¹And R^TwoFrom benzene ring, naphtha
Those forming a len ring or the like are particularly preferable. R^ThreeAs
Further preferably, hydrogen atom, methyl group, ethyl group, n-
Propyl group, iso-propyl group, t-butyl group, phenyl group
Nyl group, trifluoromethyl group, R^FourAs
And preferably 1,2-ethylene group, 1,2-phenylene
Groups, etc.

The method of synthesizing the transition metal complex of the present invention includes, for example, a method of mixing a tridentate ligand compound with a transition metal compound in a suitable solvent. As the transition metal compound, a Bronsted acid salt of a transition metal or the like is appropriately used. As the transition metal complex, a complex synthesized in advance can be used, but the complex may be formed in a reaction system.

In the present invention, the catalysts may be used alone or as a mixture. In the present invention, the catalyst can be used in any amount, but generally, the amount of the transition metal compound is preferably 0.01 to 50 mol%, more preferably 0.02 to 10 mol%, based on the phenolic starting material. Is more preferred.

(2) Phenolic Starting Material In the present invention, a starting material represented by the following structural formula is used as the phenolic starting material. (In the formula, m represents the number average number of units and 1 <m.)

When the number average unit number m = 1, that is, when the polymerization is carried out only from phenol, it is possible to use, for example, JP-B-36.
-18692 Publication and Industrial Chemistry Magazine, Volume 72, No. 10,
106 (1969). Even if a catalyst that interferes with the reaction of phenol at the ortho position is used, the resulting polymer contains a C—C bond structure, has many ortho position branches, and has a melting point. It is not observed, and it becomes impossible to produce useful poly-1,4-phenylene ether.

Specific examples of the case where the number average unit number m is larger than 1 are 4-phenoxyphenol and 4-phenoxyphenol.
(4-phenoxyphenoxy) phenol, 4- {4-
(4-phenoxyphenoxy) phenolic compounds having an integer of 2 or more 1,4-phenylene ether structural units such as phenoxydiphenol; and mixtures of at least two or more compounds selected from these compounds and phenol. Commercially available 4-phenoxyphenol can be obtained, and other compounds can be obtained by known methods. For example, the method described in Tetrahedron, 23, 2253 (1967).

The number average unit number m is 1.01 ≦ m ≦ 6
Is preferable, and 1.05 ≦ n ≦ 2 is more preferable. More preferably, 4-phenoxyphenol is used as the phenolic starting material.

(3) Oxidative Polymerization In the present invention, any oxidizing agent may be used.
Preferably, oxygen or peroxide can be used. Oxygen may be a mixture with an inert gas or air. Examples of peroxides include hydrogen peroxide, t
-Butyl hydroperoxide, di-t-butyl peroxide, cumene hydroperoxide, dicumyl peroxide, peracetic acid, perbenzoic acid, and the like. The oxidizing agent is more preferably hydroperoxide.

In the present invention, the amount of the oxidant used is not particularly limited, and when oxygen is used, it is usually used in a large excess over the equivalent amount to the phenolic starting material. When a peroxide is used, it is usually used in an amount of at least 3 equivalents, preferably at least 2 equivalents, based on the phenolic starting material.

The reaction of the present invention can be carried out in the absence of a reaction solvent, but it is generally desirable to use a solvent. The solvent is not particularly limited as long as it is inert to the phenolic starting material and liquid at the reaction temperature. Preferred examples of the solvent include aromatic hydrocarbons such as benzene, toluene and xylene; linear and cyclic aliphatic hydrocarbons such as heptane and cyclohexane; halogenated hydrocarbons such as chlorobenzene, dichlorobenzene and dichloromethane; acetonitrile , Nitriles such as benzonitrile; methanol, ethanol, n-
Alcohols such as propyl alcohol and iso-propyl alcohol; ethers such as dioxane, tetrahydrofuran and ethylene glycol dimethyl ether;
Amides such as N-dimethylformamide and N-methylpyrrolidone; nitro compounds such as nitromethane and nitrobenzene; and water. These are used alone or as a mixture.

When the solvent is used, the concentration of the phenolic starting material is preferably 0.5 to 50% by weight, more preferably 1 to 30% by weight.

When the transition metal complex has, as a counter ion, a conjugate base of an acid stronger than phenol, a base that does not inactivate the transition metal complex catalyst is made to coexist with the counter ion in an equivalent amount or more during polymerization. It is preferable. Examples of such bases are sodium hydroxide,
Hydroxides, oxides, alkoxides of alkali metals or alkaline earth metals such as potassium hydroxide, calcium oxide, sodium methoxide, sodium ethoxide; methylamine, ethylamine, propylamine, butylamine, dibutylamine, triethylamine, etc. Amines; pyridines such as pyridine, 2-methylpyridine, 2,6-dimethylpyridine, and 2,6-diphenylpyridine; Amines are commonly used,
Pyridines.

The reaction temperature for carrying out the present invention is not particularly limited as long as the reaction medium is in a liquid state. If no solvent is used, a temperature above the melting point of the phenolic starting material is required. A preferred temperature range is 0 ° C to 180 ° C, more preferably 0 ° C to 150 ° C.

[0046]

The present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited by these examples.

Conversion of Phenolic Starting Material (Conv.
): 15 mg of a reaction mixture containing diphenyl ether as an internal standard substance was sampled, acidified by adding a small amount of concentrated hydrochloric acid, and 2 g of methanol was added to obtain a measurement sample. This sample was subjected to high performance liquid chromatography (pump: 600E system manufactured by Waters, detector: UV / VIS-486 manufactured by Waters, detection wavelength: 278 nm, column: ODS-AM manufactured by YMC, developing solvent: methanol / water = Start at 50:50 and change to 100/0 after 25 minutes, then 45
Min) and diphenyl ether was quantified as an internal standard.

Infrared absorption spectrum analysis and peak area determination of polymer: Measured using a 1600 infrared spectrophotometer (KBr method) manufactured by Perkin Elmer. The quantification of the peak area was performed using analysis software (GRAMS A manufactured by PerkinElmer).
nalyst 1600).

Polymer C—C bond structure amount (CC / CO):
Regarding the infrared absorption spectrum, the C—C bond structure peak area was set to an area of 996 to 1004 cm ⁻¹ , and the C—O bond structure peak area was calculated from the area of 996 to 1018 cm ⁻¹ .
The value was obtained by subtracting the peak area of the C-bond structure. As a measure of the amount of CC bond of the polymer, a value (CC / CO / CO bond structure peak area) determined by CC bond structure peak area / CO bond structure peak area
) Was used. In addition, when CC bond structure peak was not observed, it described as ND.

Ortho branching amount of polymer (o / p): infrared absorption
As for the yield spectrum, the ortho-position branch peak area was 96
0-986cm ^-1Area. Ortho branching of polymers
As a guide of the amount, the ortho-position branch peak area / para-position connection
Use the value (o / p) determined from the peak area of the CO bond structure.
Was.

Polymer number average molecular weight (Mn), weight average molecular weight (Mw): Gel permeation chromatography (pump: Waters 600E system, detector: Waters UV / VIS-484, detection wavelength: 254 nm) , Column: Waters Ultrastyra
gel Linear = 2 + 1000A = 1 + 100A = 1
(Developing solvent: chloroform), and the weight average molecular weight (Mw) and the number average molecular weight (Mn) were measured in terms of standard polystyrene.

Melting point of polymer: Thermal analysis in a nitrogen atmosphere (DSC-50 manufactured by Shimadzu Corporation) was carried out at room temperature to 3 at room temperature at 10 ° C./min.
Raise the temperature to 00 ° C (1st scan), and then
The temperature was lowered from 00 ° C. to room temperature, and again from 10 ° C./min to 350 ° C. (2nd scan). In the 2nd scan, the peak temperature of the endothermic peak of 10 J / g or more at 100 ° C. or more was defined as the melting point.

Reference Example 1 (Synthesis of transition metal complex [VO (salap)]) A salicylaldehyde was added to a 50 ml round bottom flask equipped with a magnetic stirrer.
A solution prepared by dissolving 0.33 mmol in 20 g of methanol was added, and further 0.33 mmol of o-aminophenol was added.
Was added and stirred at room temperature overnight. To this was added sodium acetate 0.66 mmol, followed by vanadyl dichloride 0.
A solution obtained by dissolving 33 mmol in 30 g of ion-exchanged water was added, and the mixture was stirred at room temperature overnight. The precipitated solid was collected by filtration, washed 3 times with 5 ml of ion-exchanged water and 3 times with 5 ml of diethyl ether, and dried under reduced pressure at 80 ° C to obtain a complex having the following structural formula (yield 59%).

Example 1 A 25 ml two-neck round bottom flask equipped with a magnetic stirrer was equipped with a rubber balloon filled with nitrogen, and the inside of the flask was replaced with nitrogen. VO (salap) 0.030mmol is put into this, 4-phenoxyphenol (4-PhOPhOH) 1.2m
What melt | dissolved mol in o-dichlorobenzene (o-DCB) 3g was added, and also t-butyl hydroperoxide (tBuOOH) 1.8 mmol was added. While stirring the contents, the flask was kept warm in a water bath at 50 ° C. for 5 hours. After completion of the reaction, an aqueous solution in which ₂ mmol of Na ₂ SO ₃ was dissolved was added, 60 ml of methanol was added, and the precipitated polymer was collected by filtration. The polymer was washed 3 times with 10 ml of methanol, 3 times with 10 ml of deionized water, and 3 times with 10 ml of methanol, and dried under reduced pressure at 100 ° C. for 5 hours to obtain a polymer. The analysis results of this polymer are shown in Table 1, and the infrared absorption spectrum is shown in FIG.

Comparative Example 1 A 25 ml two-neck round bottom flask equipped with a magnetic stirrer was equipped with a rubber balloon filled with oxygen, and the inside of the flask was replaced with oxygen. To this, cuprous chloride (CuCl) 0.030mmo
1 was added, and 0.6 mmol of phenol (PhOH) and 2,6
A solution obtained by dissolving 0.030 mmol of dimethylpyridine (Me2Py) in 1.2 g of nitrobenzene (PhNO2) was added. While stirring the contents, the flask was kept warm in a water bath at 60 ° C. for 8 hours. After the reaction was completed, a few drops of concentrated hydrochloric acid were added to make the mixture acidic, and then 20 ml of methanol was added, and the precipitated polymer was collected by filtration. After washing three times with 10 ml of methanol and drying under reduced pressure at 100 ° C. for 5 hours, a polymer was obtained.
The analysis results of this polymer are shown in Table 1, and the infrared absorption spectrum is shown in FIG.

Comparative Examples 2 and 3 Polymers were obtained in the same manner as in Comparative Example 1 except that the phenolic starting material, catalyst, solvent, reaction temperature and reaction time were changed as shown in Table 1. The results are shown in Table 1. Incidentally, teed is N, N, N ′, N′-tetraethylethylenediamine,
PhMe represents toluene.

The polymer of Example 1 had a melting point of 196 ° C., but the polymers of Comparative Examples 1 to 3 had no melting point.

[0058]

[Table 1]

[0059]

As described above, according to the oxidative polymerization method using the specific phenolic starting material of the present invention and the catalyst of the present invention, there is no CC bond structure and no ortho-position branching. Low melting point, low color poly-
1,4-phenylene ether can be produced economically, and the industrial value of the present invention is extremely large. In addition, since the polymer obtained by this method has no CC bond structure, it is considered that there is no cross-linked structure, and improvement in mechanical properties and the like can be expected.

[Brief description of drawings]

FIG. 1 is an infrared absorption spectrum of the polymer of Example 1.

FIG. 2 is an infrared absorption spectrum of a polymer of Comparative Example 1.

Claims (6)

[Claims] 1. A fourth to eleventh per tridentate ligand whose coordinating atom is a nitrogen atom, a phosphorus atom, an oxygen atom or a sulfur atom.
A method for producing poly-1,4-phenylene ether, characterized in that a raw material represented by the following structural formula is polymerized in the presence of an oxidizing agent, using a transition metal complex catalyst having one or more group transition metal atoms. . (In the formula, m represents the number average number of units and 1 <m.) 2. The number average unit number m is 1.01 ≦ m ≦ 6.
The poly-1,4- according to claim 1, wherein
A method for producing phenylene ether. 3. The poly-1,4- according to claim 1, wherein the oxidizing agent is oxygen or peroxide.
A method for producing phenylene ether. 4. The method for producing poly-1,4-phenylene ether according to claim 1, wherein the coordination atom of the tridentate ligand is a nitrogen atom or an oxygen atom. 5. The method for producing poly-1,4-phenylene ether according to any one of claims 1 to 3, wherein the tridentate ligand is represented by the following general formula (I). (In the formula, M represents a residue containing a transition metal atom of Groups 4 to 11. R ¹ represents a hydrogen atom, a hydrocarbon group, a substituted hydrocarbon group, or O.
^-, a hydrocarbon oxy group, a substituted hydrocarbon oxy group, an amino group or a substituted amino group, R ² is a hydrogen atom, a hydrocarbon group, substituted hydrocarbon group, a hydrocarbon oxy group, a substituted hydrocarbon oxy group, hydrocarbon An oxycarbonyl group, a substituted hydrocarbon oxycarbonyl group, a cyano group, a nitro group or a halogen atom, R ³ represents a hydrogen atom, a hydrocarbon group, a substituted hydrocarbon group or O ⁻ , and R ⁴ represents a bifunctional carbon atom. It represents a hydrogen group or a substituted hydrocarbon group. R ¹ and R ² and /
Alternatively, R ² and R ³ may form a ring. Y is a counter anion, y is the number of Y, and is appropriately determined by the valence of M. ) 6. The method for producing poly-1,4-phenylene ether according to claim 1, wherein the transition metal atom is a transition metal atom of the first transition metal series.