JP2005219282A - Film manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a polyarylene stretched film excellent in mechanical strength, elastic modulus and dimensional stability at the time of heating, in obtaining a film from a composition composed of a polyarylene having a sulfonic acid group and an organic solvent by a casting method. <P>SOLUTION: The film manufacturing method includes a process for coating a substrate with a composition containing the polyarylene (I) having the sulfonic acid group and the organic solvent (II), a process for uniaxially or biaxially stretching the substrate coated with the composition and a process for heating the stretched substrate in a stretched state. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing a polyarylene-based stretched film, and more specifically, an electrolyte for a primary battery, an electrolyte for a secondary battery, a polymer solid electrolyte for a fuel cell, a display element, various sensors, a signal transmission medium, and a solid capacitor The present invention relates to a method for producing a stretched polyarylene film useful as a proton conductive membrane used for an ion exchange membrane or the like.

  The electrolyte is usually used in a (water) solution. However, in recent years, there is an increasing tendency to replace this with a solid system. The first reason is, for example, the ease of processing when applied to the above-mentioned electric / electronic materials, and the second reason is the shift to light, thin, small and high power.

  Conventionally, both proton-conducting materials made of inorganic substances and organic substances are known. Examples of inorganic substances include, for example, uranyl phosphate, which is a hydrated compound, but these inorganic compounds do not have sufficient contact at the interface, and there are many problems in forming a conductive layer on a substrate or electrode.

On the other hand, examples of organic compounds include polymers belonging to so-called cation exchange resins, for example, sulfonated products of vinyl polymers such as polystyrene sulfonic acid, perfluoroalkyl sulfonic acid polymers represented by Nafion (manufactured by DuPont), or perfluoro Polymers in which sulfonic acid groups and phosphoric acid groups are introduced into heat-resistant polymers such as alkylcarboxylic acid polymers and polybenzimidazole and polyether ether ketone [Polymer Preprints, Japan, Vol. 42, No. 7, p. 2492 (1993); Polymer Preprints, Japan, Vol.43, No.3
, P.735-736 (1994); Polymer Preprints, Japan, Vol.42, No.3, p.730 (1993)].

  These organic polymers are usually used in the form of a film, but there is an advantage that a conductive film can be bonded on an electrode by utilizing the solubility in a solvent or thermoplasticity. However, many of these organic polymers are not sufficient in proton conductivity yet, have a problem that durability and proton conductivity at a high temperature (100 ° C. or higher) are lowered, and are highly dependent on humidity conditions. There are problems, such as insufficient adhesion to the electrode, problems such as a decrease in strength or collapse of the shape due to excessive swelling during operation caused by the water-containing polymer structure. Therefore, these organic polymers have various problems when applied to the above-mentioned electric / electronic materials.

  US Pat. No. 5,403,675 (Patent Document 1) proposes a solid polymer electrolyte comprising a sulfonated rigid polyphenylene (that is, a sulfonated product having a polyarylene structure as a main component). This polymer is mainly composed of a polymer comprising a phenylene chain obtained by polymerizing an aromatic compound, and this is reacted with a sulfonating agent to introduce a sulfonic acid group. However, although the proton conductivity is improved by increasing the amount of introduced sulfonic acid groups, the mechanical properties of the resulting sulfonated polymer are significantly impaired. Therefore, it is necessary to adjust an appropriate sulfonation concentration that maintains excellent mechanical properties and exhibits proton conductivity. In fact, in this polymer, the sulfonation reaction is likely to proceed, and it is very difficult to control the proper introduction amount of the sulfonic acid group.

When the sulfonated polyarylene is used for an electric / electronic material such as a conductive film, it is usually formed into a film. Examples of a method for forming a conductive membrane using a sulfonated polyarylene include a method of dissolving a sulfonated polyarylene in an organic solvent and forming a film by a casting method. However, if the sulfonated polyarylene is simply formed into a film by the casting method, it may be in an unstretched state, so that the mechanical strength and elastic modulus of the film may be low. In addition, the polyarylene sulfonated film obtained by the casting method has a problem that it has a large shrinkage ratio upon heating and is inferior in dimensional stability.

Japanese Patent Application Laid-Open No. 2002-11787 (Patent Document 2) discloses a method of stretching and heating a film together with a substrate as means for improving the mechanical strength of the film. However, the polymer described in Patent Document 2 has a problem that it cannot be stretched at a sufficient stretch ratio because the polymer chain is rigid. Therefore, the orientation of the polyarylene molecules is not sufficient, and the mechanical strength cannot be sufficiently improved.
US Pat. No. 5,403,675 JP 2002-11787 A

  An object of the present invention is to obtain mechanical strength, elastic modulus, and dimensional stability during heating when a film is obtained from a composition containing a polyarylene having a sulfonic acid group and an organic solvent by a casting method. It is providing the manufacturing method of the outstanding polyarylene-type stretched film.

  As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention made a polyarylene containing a sulfonic acid group coated on a substrate in a film formation by a casting method of a polyarylene containing a sulfonic acid group, By stretching the substrate uniaxially or biaxially and heating in the stretched state, the film itself is not damaged by stretching, and the mechanical strength and elastic modulus are improved, and the dimensional stability during heating is increased. It was found that an excellent film can be obtained.

  That is, the method for producing a film of the present invention comprises a step of applying a composition comprising (I) a polyarylene having a sulfonic acid group and (II) an organic solvent to a substrate, and the substrate coated with the composition is uniaxial or The method includes a step of stretching in a biaxial direction and a step of heating the stretched substrate in a stretched state.

  The polyarylene having a sulfonic acid group preferably includes a repeating unit represented by the following general formula (A) and a repeating unit represented by the following general formula (B).

(In the formula, Y represents a divalent electron-withdrawing group, Z represents a divalent electron-donating group or a direct bond, and Ar represents an aromatic group having a substituent represented by —SO ₃ H. M represents an integer of 0 to 10, n represents an integer of 0 to 10, and k represents an integer of 1 to 4.)

(Wherein R ^{1 to} R ⁸ may be the same or different from each other, and at least one selected from the group consisting of a hydrogen atom, a fluorine atom, an alkyl group, a fluorine-substituted alkyl group, an allyl group, an aryl group, and a cyano group) A seed atom or group, W represents a divalent electron-withdrawing group or a single bond, T represents a single bond or a divalent organic group, and p represents a positive integer of 2 or more.)
Moreover, it is desirable that the draw ratio in the drawing is 1.01 to 5 times.

  According to the present invention, when a film is obtained by a casting method from a composition containing a polyarylene having a sulfonic acid group and an organic solvent system, the film containing the solvent is stretched together with the substrate to obtain mechanical strength and elasticity. A polyarylene-based stretched film having excellent rate and dimensional stability during heating can be obtained.

  Therefore, the polyarylene-based stretched film (proton conductive membrane) obtained from the present invention has a high Pronton conductivity over a wide temperature range without impairing the properties of the film even when used for a long time. It can be used as a conductive membrane for secondary battery electrolyte, solid polymer electrolyte for fuel cell, display element, various sensors, signal transmission medium, solid capacitor, ion exchange membrane and the like.

  Hereafter, the manufacturing method of the film which concerns on this invention is demonstrated in detail.

  In the method for producing a film according to the present invention, a composition containing (I) a polyarylene having a sulfonic acid group and (II) an organic solvent is applied to a substrate, and the substrate coated with the composition is uniaxial or biaxial. The substrate is stretched in the direction, and the stretched substrate is heated in a stretched state.

(I) Polyarylene having a sulfonic acid group The polyarylene having a sulfonic acid group used in the present invention is a repeating structural unit represented by the following general formula (A) and a repeating unit represented by the following general formula (B). It is a polymer represented by the following general formula (C) including a structural unit.

In the formula (A), Y represents a divalent electron-withdrawing group, specifically, —CO—, —SO ₂ —,
-SO -, - CONH -, - COO -, - (CF 2) l - (l is an integer of 1 to 10),
-C (CF ₃ ) _2- and the like. Z represents a divalent electron-donating group or a direct bond, and specific examples of the electron-donating group include — (CH ₂ ) —, —C (CH ₃ ) ₂ —, —O—, —S—,
-CH = CH-, -C≡C- and

Etc. The electron-withdrawing group refers to a group having a Hammett substituent constant of 0.06 or more when the phenyl group is in the m-position and 0.01 or more when it is in the p-position.

Ar represents an aromatic group having a substituent represented by —SO ₃ H, and specific examples of the aromatic group include a phenyl group, a naphthyl group, an anthracenyl group, and a phenanthyl group. Of these groups, a phenyl group and a naphthyl group are preferable.

  m represents an integer of 0 to 10, preferably 0 to 2, n represents an integer of 0 to 10, preferably 0 to 2, and k represents an integer of 1 to 4.

In formula (B), R ^{1 to} R ⁸ may be the same as or different from each other, and are selected from the group consisting of a hydrogen atom, a fluorine atom, an alkyl group, a fluorine-substituted alkyl group, an allyl group, an aryl group, and a cyano group. At least one atom or group is shown.

  Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, an amyl group, and a hexyl group, and a methyl group and an ethyl group are preferable. Examples of the fluorine-substituted alkyl group include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluorobutyl group, perfluoropentyl group, perfluorohexyl group, trifluoromethyl group, pentafluoroethyl group, and the like. Etc. are preferable. Examples of the allyl group include a propenyl group, and examples of the aryl group include a phenyl group and a pentafluorophenyl group.

  W represents a single bond or a divalent electron-withdrawing group, T represents a single bond or a divalent organic group, p is 0 or a positive integer, and the upper limit is usually 100, preferably 10 to 80 .

In the formula (C), W, T, Y, Z, Ar, m, n, k, p and R ^{1 to} R ⁸ are respectively W, T, Y in the general formulas (A) and (B). It is synonymous with Z, Ar, m, n, k, p and R ^{1 to} R ⁸ . Moreover, x and y show the molar ratio when x + y = 100 mol%.

In the polyarylene having a sulfonic acid group used in the present invention, the repeating unit represented by the formula (A) is 0.5 to 100 mol%, preferably 10 to 99.999 mol%,
The repeating unit represented by the formula (B) is contained in a ratio of 99.5 to 0 mol%, preferably 90 to 0.001 mol%.

  The polyarylene having a sulfonic acid group includes a monomer having a sulfonic acid ester group that can be a structural unit represented by the general formula (A) and an oligomer that can be a structural unit represented by the general formula (B). It can be synthesized by copolymerizing to produce a polyarylene having a sulfonic acid ester group, hydrolyzing the polyarylene having the sulfonic acid ester group, and converting the sulfonic acid ester group to a sulfonic acid group.

  The polyarylene having a sulfonic acid group is a polyarylene composed of a structural unit having no sulfonic acid group or sulfonic acid ester group in the general formula (A) and a structural unit represented by the general formula (B). It is also possible to synthesize in advance and sulphonate this polymer.

  Examples of the monomer that can be the structural unit of the general formula (A) include sulfonate esters represented by the following general formula (D) (hereinafter also referred to as monomer (D)).

In the formula (D), X is a halogen atom excluding fluorine (chlorine, bromine, iodine), -OSO ₂ G (
Here, G represents an alkyl group, a fluorine-substituted alkyl group or an aryl group. ), And Y, Z, Ar, m, n and k have the same meanings as Y, Z, Ar, m, n and k in the general formula (A), respectively.

R ^a represents a hydrocarbon group having 1 to 20 carbon atoms, preferably 4 to 20 carbon atoms. Specifically, methyl group, ethyl group, n-propyl group, iso-propyl group, tert-butyl group, iso- Butyl group, n-butyl group, sec-butyl group, neopentyl group, cyclopentyl group, hexyl group, cyclohexyl group, cyclopentylmethyl group, cyclohexylmethyl group, adamantyl group, adamantanemethyl group, 2-ethylhexyl group, bicyclo [2.2 .1] heptyl group, bicyclo [2.2.1] heptylmethyl group, tetrahydrofurfuryl group, 2-methylbutyl group, 3,3-dimethyl-2,4-dioxolanemethyl group, cyclohexylmethyl group, adamantylmethyl group , Straight chain hydrocarbon group such as bicyclo [2.2.1] heptylmethyl group, branched hydrocarbon group, alicyclic hydrocarbon group, 5-membered And a hydrocarbon group having a heterocyclic ring. Among these, n-butyl group, neopentyl group, tetrahydrofurfuryl group, cyclopentyl group, cyclohexyl group, cyclohexylmethyl group, adamantylmethyl group, and bicyclo [2.2.1] heptylmethyl group are preferable, and neopentyl group is particularly preferable. preferable.

Ar represents an aromatic group having a substituent represented by —SO ₃ R ^b , and specific examples of the aromatic group include a phenyl group, a naphthyl group, an anthracenyl group, and a phenanthyl group. Of these groups, a phenyl group and a naphthyl group are preferable.

The substituent —SO ₃ R ^b is substituted with one or more aromatic groups, and when two or more substituents —SO ₃ R ^b are substituted, these substituents are the same as each other. But it can be different.

Here, R ^b represents a hydrocarbon group having 1 to 20 carbon atoms, preferably 4 to 20 carbon atoms, and specific examples thereof include the hydrocarbon groups having 1 to 20 carbon atoms. Among these, n-butyl group, neopentyl group, tetrahydrofurfuryl group, cyclopentyl group, cyclohexyl group, cyclohexylmethyl group, adamantylmethyl group, and bicyclo [2.2.1] heptylmethyl group are preferable, and neopentyl group is particularly preferable. preferable.

  m represents an integer of 0 to 10, preferably 0 to 2, n represents an integer of 0 to 10, preferably 0 to 2, and k represents an integer of 1 to 4.

  Specific examples of the sulfonic acid ester represented by the formula (D) include the following compounds.

In the above compound, a compound in which a chlorine atom is replaced by a bromine atom, a compound in which -CO- is replaced by -SO ₂ -in the above compound, a chlorine atom in the above compound is replaced by a bromine atom, and -CO- is -SO 2 Examples include compounds in which _2- is replaced.

The R ^b group in the general formula (D) is derived from a primary alcohol, and the β carbon is a tertiary or quaternary carbon, which is excellent in stability during the polymerization process, and produces sulfonic acid by deesterification. It is preferable in that it does not cause polymerization inhibition and cross-linking, and it is preferable that these ester groups are derived from primary alcohols and the β-position is a quaternary carbon.

  In the above general formula (D), specific examples of the compound having no sulfonic acid group or sulfonic acid ester group include the following compounds.

A compound in which the chlorine atom is replaced with a bromine atom in the above compound, a compound in which —CO— is replaced with —SO ₂ — in the above compound, a chlorine atom in the above compound is replaced with a bromine atom, and —CO— is —SO ₂ —. And compounds that have been replaced with.

  Examples of the oligomer that can be the structural unit of the general formula (B) include an oligomer represented by the following general formula (E) (hereinafter also referred to as oligomer (E)).

In the formula (E), R ′ and R ″ may be the same as or different from each other, and a halogen atom or —OSO ₂ G excluding a fluorine atom (where G represents an alkyl group, a fluorine-substituted alkyl group or an aryl group) The group represented by this is shown. Examples of the alkyl group represented by G include a methyl group and an ethyl group, examples of the fluorine-substituted alkyl group include a trifluoromethyl group, and examples of the aryl group include a phenyl group and a p-tolyl group.

R ^{1 to} R ⁸ may be the same or different from each other, and are at least one atom or group selected from the group consisting of a hydrogen atom, a fluorine atom, an alkyl group, a fluorine-substituted alkyl group, an allyl group, an aryl group, and a cyano group. Indicates.

  Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, an amyl group, and a hexyl group, and a methyl group and an ethyl group are preferable. Examples of the fluorine-substituted alkyl group include trifluoromethyl group, perfluoroethyl group, perfluoropropyl group, perfluorobutyl group, perfluoropentyl group, perfluorohexyl group, trifluoromethyl group, pentafluoroethyl group, and the like. Etc. are preferable. Examples of the allyl group include a propenyl group, and examples of the aryl group include a phenyl group and a pentafluorophenyl group.

  W represents a divalent electron-withdrawing group or a single bond, and examples of the electron-withdrawing group include those described above. T is a divalent organic group or a single bond, and may be an electron-withdrawing group or an electron-donating group. Examples of the electron-withdrawing group and the electron-donating group include the same groups as described above. p is 0 or a positive integer, and the upper limit is usually 100, preferably 10-80.

The compound represented by the general formula (E) is 2,2-bis [4- {4- (4-chlorobenzoyl) phenoxy} phenyl] -1,1,1,3,3,3-hexafluoro. propane,
Examples thereof include bis [4- {4- (4-chlorobenzoyl) phenoxy} phenyl] sulfone, and a compound represented by the following formula.

  The compound represented by the general formula (E) can be synthesized, for example, by the method shown below.

  First, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, sulfolane, diphenylsulfone, dimethylsulfoxide, etc., in order to convert the bisphenol linked with an electron-withdrawing group to the corresponding alkali metal salt of bisphenol In a polar solvent having a high dielectric constant, an alkali metal such as lithium, sodium or potassium, an alkali metal hydride, an alkali metal hydroxide, an alkali metal carbonate or the like is added.

The alkali metal is reacted in excess with respect to the hydroxyl group of phenol, and is usually used in an amount of 1.1 to 2 times equivalent, preferably 1.2 to 1.5 times equivalent. In this case, fluorine, chlorine, etc. activated with an electron-withdrawing group in the presence of azeotropic solvent such as benzene, toluene, xylene, hexane, cyclohexane, octane, chlorobenzene, dioxane, tetrahydrofuran, anisole, phenetole, etc. Aromatic halogen-substituted aromatic dihalide compounds such as 4,4′-difluorobenzophenone, 4,4′-dichlorobenzophenone, 4,4′-chlorofluorobenzophenone, bis (4-chlorophenyl) sulfone, bis (4 -Fluorophenyl) sulfone, 4-fluorophenyl-4'-chlorophenylsulfone, bis (3-nitro-4-chlorophenyl) sulfone, 2,6-dichlorobenzonitrile, 2,6-difluorobenzonitrile, hexafluorobenzene, deca Fluorobiphenyl, ,
5-difluorobenzophenone, 1,3-bis (4-chlorobenzoyl) benzene and the like are reacted. In terms of reactivity, a fluorine compound is preferable, but in consideration of the following aromatic coupling reaction, it is necessary to assemble an aromatic nucleophilic substitution reaction so that the terminal is a chlorine atom.

  The active aromatic dihalide is used in an amount of 2 to 4 times mol, preferably 2.2 to 2.8 times mol, of bisphenol. Prior to the aromatic nucleophilic substitution reaction, an alkali metal salt of bisphenol may be used. The reaction temperature is 60 ° C to 300 ° C, preferably 80 ° C to 250 ° C. The reaction time ranges from 15 minutes to 100 hours, preferably from 1 hour to 24 hours. The most preferable method is to use a chlorofluoro compound having one halogen atom having a different reactivity as the active aromatic dihalide represented by the following formula, and a nucleophilic substitution reaction with phenoxide occurs preferentially by the fluorine atom. It is convenient to obtain the desired activated terminal chloro form.

  In the formula, W is as defined for the general formula (E).

  Further, as described in JP-A-2-159, a flexible compound comprising a target electron-withdrawing group and electron-donating group may be synthesized by combining a nucleophilic substitution reaction and an electrophilic substitution reaction. .

  Specifically, an aromatic bishalide activated with an electron-withdrawing group, for example, bis (4-chlorophenyl) sulfone is subjected to a nucleophilic substitution reaction with phenol to form a bisphenoxy compound, and then this bisphenoxy compound and 4-chloro The desired compound can be obtained from Friedel-Craft reaction with benzoic acid chloride.

  Examples of the aromatic bishalide activated with the electron-withdrawing group used here include the compounds exemplified above. The phenol compound may be substituted, but an unsubstituted compound is preferable from the viewpoint of heat resistance and flexibility. In addition, it is preferable to set it as an alkali metal salt for the substitution reaction of a phenol, and the compound illustrated above is mentioned as an alkali metal compound which can be used. The amount used is 1.2 to 2 moles per mole of phenol. In the reaction, the polar solvent described above or an azeotropic solvent with water can be used.

  Chlorobenzoic acid chloride is used in an amount of 2 to 4 times mol, preferably 2.2 to 3 times mol of the bisphenoxy compound. Further, the Friedel-Crafts reaction between the bisphenoxy compound and the acylating agent chlorobenzoic acid chloride is preferably performed in the presence of a Friedel-Craft activator such as aluminum chloride, boron trifluoride, or zinc chloride. . The Friedel-Craft activator is used in an amount of 1.1 to 2 times equivalent to 1 mol of an active halide compound such as chlorobenzoic acid as an acylating agent. The reaction time ranges from 15 minutes to 10 hours, and the reaction temperature ranges from -20 ° C to 80 ° C. As the solvent used, chlorobenzene, nitrobenzene and the like which are inert to Friedel-Craft reaction can be used.

Further, in the general formula (E), the compound in which p is 2 or more is, for example, a bisphenol that is a source of etheric oxygen that is the electron donating group T in the general formula (E) and an electron withdrawing group W. A compound in combination with at least one group selected from> C═O, —SO ₂ — and> C (CF ₃ ) ₂ , specifically 2,2-bis (4-hydroxyphenyl) -1 1,1,3,3,3-hexafluoropropane, alkali metal salts of bisphenols such as 2,2-bis (4-hydroxyphenyl) ketone, 2,2-bis (4-hydroxyphenyl) sulfone, and excess Substitution reaction with an active aromatic halogen compound such as 4,4-dichlorobenzophenone or bis (4-chlorophenyl) sulfone is carried out with N-methyl-2-pyrrolidone, N, N
-Obtained by sequentially polymerizing the monomer in the presence of a polar solvent such as dimethylacetamide or sulfolane.

Examples of such compounds include compounds represented by the following formulas.

  In the above chemical formula, p is 0 or a positive integer, and the upper limit is usually 100, preferably 10-80.

  The polyarylene having a sulfonate group is synthesized by reacting the monomer (D) and the oligomer (E) in the presence of a catalyst. The catalyst used in this case is a catalyst containing a transition metal compound. This catalyst system includes (1) a transition metal salt and a compound that becomes a ligand (hereinafter referred to as “ligand component”), or a transition metal complex in which a ligand is coordinated (copper). Salt is included), and (2) a reducing agent is an essential component, and a “salt” may be added to increase the polymerization rate.

  Here, as the transition metal salt, nickel compounds such as nickel chloride, nickel bromide, nickel iodide and nickel acetylacetonate; palladium compounds such as palladium chloride, palladium bromide and palladium iodide; iron chloride and iron bromide And iron compounds such as iron iodide; cobalt compounds such as cobalt chloride, cobalt bromide, and cobalt iodide. Of these, nickel chloride, nickel bromide and the like are particularly preferable.

As the ligand component, triphenylphosphine, 2,2′-bipyridine, 1,5-
Examples include cyclooctadiene and 1,3-bis (diphenylphosphino) propane. Of these, triphenylphosphine and 2,2′-bipyridine are preferred. The compound which is the said ligand component may be used individually by 1 type, and may use 2 or more types together.

Furthermore, as the transition metal complex in which the ligand is coordinated, for example, nickel chloride bis (triphenylphosphine), nickel bromide bis (triphenylphosphine), nickel iodide bis (triphenylphosphine), nickel nitrate bis (Triphenylphosphine), nickel chloride (2,2'-bipyridine), nickel bromide (2,2'-bipyridine), nickel iodide (2,2'-bipyridine), nickel nitrate (2,2'-bipyridine) ), Bis (1,5-cyclooctadiene) nickel, tetrakis (triphenylphosphine) nickel, tetrakis (triphenylphosphite) nickel, tetrakis (triphenylphosphine) palladium and the like. Of these, nickel chloride bis (triphenylphosphine) and nickel chloride (2,2′-bipyridine) are preferred.

  Examples of the reducing agent that can be used in the catalyst system include iron, zinc, manganese, aluminum, magnesium, sodium, calcium, and the like. Of these, zinc, magnesium and manganese are preferred. These reducing agents can be used after being more activated by bringing them into contact with an acid such as an organic acid.

  “Salts” that can be used in the above catalyst system include sodium compounds such as sodium fluoride, sodium chloride, sodium bromide, sodium iodide, sodium sulfate; potassium fluoride, potassium chloride, potassium bromide, Examples include potassium compounds such as potassium iodide and potassium sulfate; ammonium compounds such as tetraethylammonium fluoride, tetraethylammonium chloride, tetraethylammonium bromide, tetraethylammonium iodide, and tetraethylammonium sulfate. Of these, sodium bromide, sodium iodide, potassium bromide, tetraethylammonium bromide, and tetraethylammonium iodide are preferred.

  The proportion of each component used is usually from 0.0001 to 10 mol, preferably 0.01, based on 1 mol of the total amount of the above monomers ((D) + (E), hereinafter the same) of the transition metal salt or transition metal complex. -0.5 mol. When the amount is less than 0.0001 mol, the polymerization reaction may not proceed sufficiently. On the other hand, when the amount exceeds 10 mol, the molecular weight may decrease.

  In the catalyst system, when a transition metal salt and a ligand component are used, the ratio of the ligand component used is usually 0.1 to 100 mol, preferably 1 to 10 mol, per 1 mol of the transition metal salt. . When the amount is less than 0.1 mol, the catalytic activity may be insufficient. On the other hand, when the amount exceeds 100 mol, the molecular weight may decrease.

  Moreover, the usage-amount of a reducing agent is 0.1-100 mol normally with respect to the total of 1 mol of the said monomer, Preferably it is 1-10 mol. If the amount is less than 0.1 mol, polymerization may not proceed sufficiently. If the amount exceeds 100 mol, purification of the resulting polymer may be difficult.

  Furthermore, when using "salt", the usage-ratio is 0.001-100 mol normally with respect to the total of 1 mol of the said monomer, Preferably it is 0.01-1 mol. If it is less than 0.001 mol, the effect of increasing the polymerization rate may be insufficient, and if it exceeds 100 mol, purification of the resulting polymer may be difficult.

Examples of the polymerization solvent that can be used when the monomer (D) and the oligomer (E) are reacted include tetrahydrofuran, cyclohexanone, dimethyl sulfoxide, N,
N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, γ-butyrolactone, N, N′-dimethylimidazolidinone and the like can be mentioned. Of these, tetrahydrofuran, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and N, N′-dimethylimidazolidinone are preferable. These polymerization solvents are preferably used after sufficiently dried.

  The total concentration of the monomers in the polymerization solvent is usually 1 to 90% by weight, preferably 5 to 40% by weight.

  The polymerization temperature for the polymerization is usually 0 to 200 ° C, preferably 50 to 120 ° C. The polymerization time is usually 0.5 to 100 hours, preferably 1 to 40 hours.

  The polyarylene having a sulfonic acid ester group obtained using the monomer (D) can be converted into a polyarylene having a sulfonic acid group by hydrolyzing the sulfonic acid ester group and converting it to a sulfonic acid group. .

As a hydrolysis method,
(1) A method in which polyarylene having a sulfonate group is added to an excess amount of water or alcohol containing a small amount of hydrochloric acid, and the mixture is stirred for 5 minutes or longer. (2) In trifluoroacetic acid, the sulfonate group is added. (3) Method of reacting polyarylene having a temperature of about 80 to 120 ° C. for about 5 to 10 hours (3) 1 to 1 mol of sulfonic acid ester group (—SO ₃ R) in polyarylene having a sulfonic acid ester group A method of adding hydrochloric acid after reacting the polyarylene for about 3 to 10 hours at a temperature of about 80 to 150 ° C. in a solution containing 3 moles of lithium bromide such as N-methylpyrrolidone. Can be mentioned.

  The polyarylene (C) having a sulfonic acid group includes a monomer having no sulfonic acid ester group in the monomer (D) represented by the general formula (D), and an oligomer represented by the general formula (E) ( It is also possible to synthesize a polyarylene copolymer in advance by copolymerizing with E) and sulphonate the polyarylene copolymer. In this case, after producing a polyarylene having no sulfonic acid group by a method according to the above synthesis method, a sulfonic acid group is introduced into the polyarylene having no sulfonic acid group using a sulfonating agent. A polyarylene (C) having a group can be obtained.

  The introduction of the sulfonic acid group is not particularly limited, and can be performed by a general method. For example, the polyarylene having no sulfonic acid group may be prepared by using a known sulfonating agent such as sulfuric anhydride, fuming sulfuric acid, chlorosulfonic acid, sulfuric acid or sodium hydrogen sulfite in the absence of a solvent or in the presence of a solvent. Sulfonic acid groups can be introduced by sulfonation under conditions [Polymer Preprints, Japan, Vol. 42, No. 3, p. 730 (1993); Polymer Preprints, Japan, Vol. 43, No. 3 , P. 736 (1994); Polymer Preprints, Japan, Vol. 42, No. 7, p. 2490-2492 (1993)].

  Examples of the solvent used in sulfonation include hydrocarbon solvents such as n-hexane, ether solvents such as tetrahydrofuran and dioxane, aprotic polar solvents such as dimethylacetamide, dimethylformamide, and dimethylsulfoxide, tetrachloroethane, Halogenated hydrocarbons such as dichloroethane, chloroform, and methylene chloride. Although reaction temperature does not have a restriction | limiting in particular, Usually, -50-200 degreeC, Preferably it is -10-100 degreeC. Moreover, reaction time is 0.5 to 1,000 hours normally, Preferably it is 1 to 200 hours.

  The amount of the sulfonic acid group in the polyarylene (C) having a sulfonic acid group produced by the method as described above is usually 0.3 to 5 meq / g, preferably 0.5 to 3 meq / g, more preferably 0. .8 to 2.8 meq / g. If it is less than 0.3 meq / g, the proton conductivity is low and not practical. On the other hand, if it exceeds 5 meq / g, the water resistance may be significantly lowered, which is not preferable.

The amount of the sulfonic acid group can be adjusted, for example, by changing the type, usage ratio, and combination of the monomer (D) and the oligomer (E).

  The molecular weight of the polyarylene having a sulfonic acid group thus obtained is 10,000 to 1,000,000, preferably 20,000 to 800,000 in terms of polystyrene-equivalent weight average molecular weight by gel permeation chromatography (GPC). If it is less than 10,000, there are insufficient coating properties such as cracks in the molded film, and there are also problems in strength properties. On the other hand, when it exceeds 1,000,000, there is a problem that the solubility becomes insufficient and the workability is deteriorated because the solution viscosity becomes high.

  The polyarylene having a sulfonic acid group may contain an anti-aging agent, preferably a hindered phenol compound having a molecular weight of 500 or more. By containing the anti-aging agent, durability as an electrolyte is further improved. be able to.

Examples of hindered phenol compounds that can be used in the present invention include triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate] (trade name: IRGANOX 245), 1,6-hexanediol-bis [3- (3.5
-Di-t-butyl-4-hydroxyphenyl) propionate] (trade name: IRGANOX 259
) 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -3,5-triazine (trade name: IRGANOX 565), pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (trade name: IRGANOX 1010), 2,2-thio-diethylenebis [3- (3,5-di-t-butyl -4
-Hydroxyphenyl) propionate] (trade name: IRGANOX 1035), octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) (trade name: IRGANOX
1076), N, N-hexamethylenebis (3,5-di-tert-butyl-4-hydroxy-hydrocinnamamide) (IRGAONOX 1098), 1,3,5-trimethyl-2,4,6-tris ( 3,5-di-t-butyl-4-hydroxybenzyl) benzene (trade name: IRGANOX 1330), tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate (trade name: IRGANOX 3114) 3,9-bis [2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1-dimethylethyl] -2,4,8,10 -Tetraoxaspiro [5.5] undecane (trade name: Sumilizer GA-80). The hindered phenol compound is preferably used in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the polyarylene having a sulfonic acid group.

(II) Organic solvent Examples of the organic solvent used in the present invention include N-methyl-2-pyrrolidone, methanol, ethanol, propanol, tetrahydrofuran, cyclohexanone, dimethyl sulfoxide, N, N-dimethylformamide, and N, N-dimethyl. Acetamide, γ-butyrolactone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol dimethyl ether, ethylene glycol methyl ethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether , Diethylene glycol ethyl methyl ether Diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, toluene, xylene, methyl amyl ketone, 4-hydroxy-4-methyl-2-pentanone, ethyl 2-hydroxypropionate, Methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-2-methylbutanoate, methyl 3-methoxypropionate, 3-methoxy Mention may be made of ethyl propionate, methyl 3-ethoxypropionate, ethyl 3-methoxypropionate, methyl lactate, ethyl lactate, chloroform, methylene chloride, etc. it can. Among these, N-methyl-2-pyrrolidone, methanol, propanol, propylene glycol monomethyl ether, γ-butyrolactone, N, N-dimethylformamide, ethyl carbitol, and methyl carbitol are preferable. The said organic solvent may be used independently and may be used in mixture of 2 or more types.

Polyarylene-based composition The polyarylene-based composition used in the present invention contains (I) the polyarylene having a sulfonic acid group and (II) an organic solvent, but the solid content concentration in the composition, that is, the component The proportion of (I) is usually 3 to 40% by weight, preferably 5 to 35% by weight, based on the entire composition. If it is less than 3% by weight, a coating film having a sufficient thickness may not be obtained. On the other hand, if it exceeds 40% by weight, it may not be sufficiently cast and a uniform coating film may not be obtained.

  Moreover, the viscosity at room temperature of the composition used in the present invention is usually 1 to 1,000,000 mPa · s, preferably 10 to 100,000 mPa · s, more preferably 100 to 80,000 mPa · s, particularly Preferably it is 1000-60,000 mPa * s. If it is less than 1 mPa · s, it cannot be formed into a film at the time of coating. On the other hand, if it exceeds 1,000,000 mPa · s, it may not be sufficiently cast and a uniform coating film may not be obtained.

  In addition, although the composition used for this invention has the said component (I) and (II) as a main component, an additive, for example, a leveling agent, a silane coupling agent, etc. can be added as needed.

  Any leveling agent that is generally used can be used as the leveling agent. For example, a fluorine-based nonionic surfactant, a special acrylic resin-based leveling agent, a silicone-based leveling agent, and the like can be used.

Method for Producing Film According to the present invention, a method for producing a film having excellent proton conductivity (proton conductive membrane) is obtained by dissolving the polyarylene (I) having a sulfonic acid group in the organic solvent (II) to form a polyarylene system. After the composition is formed, the polyarylene-based composition is applied to a substrate, the substrate coated with the composition is uniaxially or biaxially stretched, and then the stretched substrate is heated in a stretched state.

  The method for applying the polyarylene-based composition to the substrate is not particularly limited, and for example, it can be applied using means such as a die, a coater, a spray, a brush, a roll spin coat, or a dipping. In addition, you may control the thickness of a film, surface smoothness, etc. by repetition of application | coating.

  The substrate that can be used in the present invention includes polyethylene terephthalate (PET) film, polyethylene naphthalate (PEN) film, polybutylene terephthalate (PBT) film, nylon 6 film, nylon 6,6 film, polypropylene film, polytetra A fluoroethylene film etc. are mentioned, Preferably it is a PET film.

When a PET film is used as the substrate, it is preferable to use a non-surface-treated film, but a surface-treated film may be used. As the surface treatment method, a hydrophilic treatment method generally used, for example, a method of laminating an acrylic resin or a sulfonate group-containing resin by coating or laminating, or a corona discharge treatment or the like, Examples thereof include a method for improving hydrophilicity. Further, as other surface treatment methods, a release treatment that is generally performed, for example, a method of coating a silicon compound, and the like can be mentioned.

  Moreover, the thickness of the film used as this base | substrate is 25-250 micrometers normally, Preferably it is 50-200 micrometers. If the thickness is less than 25 μm, the rigidity of the substrate may be insufficient and the proton conductive membrane may not be uniform. If the thickness exceeds 250 μm, heat conduction during drying may be poor and sufficient drying may not be possible.

  In the method for producing the film, it is preferable to pre-dry the substrate coated with the composition before stretching. The preliminary drying can be performed by a generally used method, for example, a method of passing through a drying furnace through a large number of rollers. However, in the preliminary drying step, if bubbles are generated as the solvent evaporates, the film characteristics are reduced. May decrease significantly. Therefore, it is preferable that the drying process is a plurality of processes of two or more stages, and the temperature or the air volume in each process is controlled. Each step may be dried at, for example, 30 to 200 ° C., preferably 50 to 180 ° C., for 10 to 180 minutes, preferably 15 to 60 minutes.

  The solid concentration in the film after this preliminary drying step is preferably 50 to 90% by weight, more preferably 60 to 90% by weight. As described above, in the preliminary drying step, the organic solvent (II) is left in the film, whereby the stretching can be smoothly performed in the stretching step.

The thickness of the film obtained by the production method of the present invention is usually 0.1 to 1,000 μm,
Preferably it is 1-800 micrometers, More preferably, it is 5-500 micrometers, Most preferably, it is 10-300 micrometers. When the thickness of the film is less than 0.1 μm, handling becomes substantially difficult, and when it exceeds 1,000 μm, proton conductivity may be lowered.

  The thickness distribution of the film obtained by the production method of the present invention is usually within ± 30%, preferably within ± 20%, more preferably within ± 15%, particularly preferably within ± 10% with respect to the average value of thickness. is there. By carrying out such thickness control, it is possible to prevent unevenness in strength when stretched and oriented.

  Stretching in the method for producing a polyarylene stretched film according to the present invention can be performed by a known uniaxial stretching method or biaxial stretching method. That is, a uniaxial stretching method such as a transverse uniaxial stretching method using a tenter method, a compression stretching method between rolls, a longitudinal uniaxial stretching method using two sets of rolls with different circumferences, or a lateral uniaxial stretching method and a longitudinal uniaxial stretching method are combined. A combined biaxial stretching method can be used. In the case of using a single wafer, uniaxial stretching and biaxial stretching can be performed by fixing an end portion around the film with a chuck and moving the chuck portion in each direction.

  In the stretching step, the substrate and the film cast on the substrate may be preheated. The preheating method is not particularly limited, and heating can be performed using a generally used method such as hot air, an infrared heater, or a far infrared heater. The heating temperature is usually 50 to 200 ° C, preferably 60 to 180 ° C, more preferably 80 to 160 ° C. In the stretching step, the substrate and the film cast on the substrate are preheated, whereby stretching can be performed smoothly with a high stretching ratio.

  In the case of the uniaxial stretching method, the stretching speed is usually 1 to 5,000% / min, preferably 50 to 1,000% / min, more preferably 100 to 1,000% / min, and particularly preferably 100 to 500%. / Min.

In the case of the biaxial stretching method, there are a method of stretching simultaneously in two directions, or a method of stretching in a direction different from the first stretching direction after uniaxial stretching. At this time, the intersecting angle of the two stretching axes for controlling the strength of the stretched film is not particularly limited because it is determined by desired characteristics, but is usually in the range of 120 to 60 degrees. The stretching speed may be the same or different in each stretching direction, and is usually 1 to 5,000% / min, preferably 50 to 1,000% / min, more preferably 100 to 1, 000% / min, particularly preferably 100 to 500% / min.

  Although a draw ratio is determined according to desired characteristics, it is usually 1.01 to 5 times, preferably 1.03 to 3 times, and more preferably 1.05 to 1.75 times. When the draw ratio is less than 1.01, the mechanical strength of the resulting film is not sufficiently improved. On the other hand, when it exceeds 5 times, uniform orientation becomes difficult.

  As described above, by stretching the film with the organic solvent (II) remaining in the film, a high stretch ratio is achieved, and the molecular chain arrangement of the component (I) is uniformly aligned in the stretching direction. No damage caused by stretching.

After stretching, the substrate on which the film is formed in the stretched state is 50 to 200 ° C., preferably 60 to 180 ° C., more preferably 80 to 160 ° C., and 0.01 to 10 hours, preferably 0. .Heat set (post-heating treatment) for 1-5 hours. By this post-heating treatment, the film is heat-set in the stretched state, the molecular chain of polyarylene (I) having a sulfonic acid group is fixed, and the mechanical properties (strength, elastic modulus) of the film and dimensional stability during heating Improves.

  In addition, the atmospheric pressure of this post-heating process is the range of a normal pressure to a vacuum, Preferably it is 300 mmHg-0.1 mmHg. By performing the post-heating treatment under reduced pressure, the organic solvent (II) can be completely volatilized at a lower temperature and in a shorter time.

  Further, as a method for completely removing the organic solvent (II), a method of putting the stretched film in pure water can be performed in order to shorten the processing time.

  The film (proton conductive membrane) obtained by the method of the present invention has improved strength properties (strength and elastic modulus) of the film and is excellent in dimensional stability during heating (shrinkage can be suppressed). Therefore, the film obtained by the present invention is used for, for example, an electrolyte for a primary battery, an electrolyte for a secondary battery, a polymer solid electrolyte for a fuel cell, a display element, various sensors, a signal transmission medium, a solid capacitor, an ion exchange membrane, and the like. It can be used as a proton conducting membrane.

〔Example〕
EXAMPLES Hereinafter, although this invention is demonstrated further more concretely based on an Example, this invention is not limited to these Examples. Various physical properties were determined as follows.

1. Molecular weight The polyarylene weight average molecular weight having no sulfonic acid group was determined by GPC using polystyrene (THF) as a solvent and the molecular weight in terms of polystyrene. The molecular weight of the polyarylene having a sulfonic acid group was determined by GPC using N-methyl-2-pyrrolidone (NMP) to which lithium bromide and phosphoric acid were added as a solvent as an eluent.

2. Sulfonic acid equivalent The polymer having the sulfonic acid group was washed with water until the water was neutral, thoroughly washed with water except for free remaining acid, dried, weighed a predetermined amount, THF / Phenolphthalein dissolved in a mixed solvent of water was used as an indicator, titration was performed using a standard solution of NaOH, and the sulfonic acid equivalent was determined from the neutralization point.

3. Measurement of proton conductivity AC resistance is measured by pressing a platinum wire (φ = 0.5 mm) against the surface of a strip-shaped proton conducting membrane sample with a width of 5 mm, holding the sample in a constant temperature and humidity device, and between the platinum wires It was obtained from AC impedance measurement. That is, the impedance at AC 10 kHz was measured in an environment of 85 ° C. and relative humidity 90%. A chemical impedance measurement system manufactured by NF Circuit Design Block Co., Ltd. was used as the resistance measurement device, and JW241 manufactured by Yamato Scientific Co., Ltd. was used as the constant temperature and humidity device. Five platinum wires were pressed at intervals of 5 mm, the distance between the wires was changed to 5 to 20 mm, and the AC resistance was measured. The specific resistance of the membrane was calculated from the line-to-line distance and the resistance gradient, and the proton conductivity was calculated from the reciprocal of the specific resistance.
Specific resistance R (Ω · cm) = 0.5 (cm) × film thickness (cm) × resistance-to-resistance gradient (Ω / cm)
4). Tensile strength Tensile strength was measured at room temperature using No. 2 type test piece of the obtained film according to JIS K7127.

5). Elastic modulus The elastic modulus was calculated from the initial inclination of the stress-strain curve in the tensile strength measurement.

6). Film folding resistance Using a MIT folding resistance tester (manufactured by Uesima), measurement was performed under the conditions of a number of flexing cycles of 166 times / minute, a load of 200 g, and a flexural deformation angle of 135 °.

7). Dimensional stability (dimensional change rate)
The obtained film was treated in an oven at 100 ° C. for 3 hours, and the dimensional change rate of the film before and after the treatment was shown in%.

8). Water absorption rate The obtained film was immersed in distilled water at room temperature for 1 hour, and determined from the change in weight before and after the immersion.

[Synthesis Example 1] Preparation of Oligomer 2,2-bis (4-hydroxyphenyl) was added to a 1 L three-necked flask equipped with a stirrer, thermometer, condenser, Dean-Stark tube and nitrogen-introduced three-way cock. -1,1,1,3,3,3-hexafluoropropane (bisphenol AF) 67.3 g (0.20 mol), 4,4′-dichlorobenzophenone (4,4′-DCBP) 60.3 g (0. 24 mol), potassium carbonate 71.9 g (0.52 mol), N, N-dimethylacetamide (DMAc) 300 m
L and 150 mL of toluene were taken and heated in an oil bath under a nitrogen atmosphere and reacted at 130 ° C. with stirring. When water produced by the reaction was azeotroped with toluene and reacted while being removed from the system with a Dean-Stark tube, almost no water was produced in about 3 hours. Thereafter, most of the toluene was removed while gradually raising the reaction temperature from 130 ° C. to 150 ° C., and the reaction was continued at 150 ° C. for 10 hours, and then 10.0 g (0.040 mol) of 4,4′-DCBP was added. The mixture was further reacted for 5 hours. The resulting reaction solution was allowed to cool, and then the by-product inorganic compound precipitate was removed by filtration, and the filtrate was put into 4 L of methanol. The precipitated product was separated by filtration, collected, dried, and dissolved in 300 mL of tetrahydrofuran. This was reprecipitated in 4 L of methanol to obtain 95 g (yield 85%) of the target compound.

The weight average molecular weight (Mw) in terms of polystyrene determined by GPC (THF solvent) of the obtained compound was 11,200. Further, the obtained compound was soluble in THF, NMP, DMAc, sulfolane and the like, Tg was 110 ° C., and thermal decomposition temperature was 498 ° C. The obtained compound was an oligomer represented by the formula (I) (hereinafter referred to as “BCPAF oligomer”).

[Synthesis Example 2] Polymer Synthesis Example To a 1 L three-necked flask equipped with a stirrer, a thermometer, a condenser tube, a Dean-Stark tube, and a nitrogen-introduced three-way cock, 4- [4- (2,5 -Dichlorobenzoyl) phenoxy] 39-58 g (98.64 mmol) of benzenesulfonic acid neo-pentyl (A-SO ₃ neo-Pe), 15.23 g (1.36 mmol) of BCPAF oligomer (Mw = 11200), Ni (PPh _{3 ) 2 Cl 2 1.67g (2.55mmol)} , PPh 3 10.49g (40mmol), NaI 0.45g (3mmol), zinc dust 15.69 g (240 mmol), dry NMP 390 mL was added under nitrogen. The reaction system was heated with stirring (finally heated to 75 ° C.) and allowed to react for 3 hours. The polymerization reaction solution was diluted with 250 mL of THF, stirred for 30 minutes,
Celite was filtered using a filter aid, and the filtrate was poured into 1500 mL of a large excess of methanol to coagulate. The coagulum was collected by filtration, air-dried, redissolved in THF / NMP (200/300 mL each), and coagulated with 1500 mL of a large excess of methanol. After air drying, 47.0 g (yield 99%) of a copolymer (PolyAB-SO ₃ neo-Pe) composed of a sulfonic acid derivative protected with a target yellow fibrous neopentyl group was obtained by heat drying. As for the molecular weight by GPC, the number average molecular weight (Mn) was 47,600, and Mw was 159,000.

PolyAB-SO ₃ neo-Pe thus obtained (5.1 g) was dissolved in NMP (60 mL) and heated to 90 ° C. A mixture of 50 mL of methanol and 8 mL of concentrated hydrochloric acid was added to the reaction system at one time. While in suspension, the reaction was allowed to proceed for 10 hours under mild reflux conditions. A distillation apparatus was installed, and excess methanol was distilled off to obtain a light green transparent solution. This solution was poured into a large amount of water / methanol (1: 1 weight ratio) to solidify the polymer, and then the polymer was washed with ion-exchanged water until the pH of the washing water became 6 or more. From the IR spectrum of the polymer thus obtained and the quantitative analysis of the ion exchange capacity, it was found that the sulfonic acid ester group (—SO ₃ R ^a ) was quantitatively converted to the sulfonic acid group (—SO ₃ H). . The obtained polyarylene copolymer having a sulfonic acid group had a molecular weight of GPC of Mn of 53,200, Mw of 185,000, and a sulfonic acid equivalent of 1.9 meq / g.

[Synthesis Example 3] Synthesis Example of Postsulfonated Polymer (Synthesis of Polyarylene Copolymer)
28.1 g (2.5 mmol) of the oligomer of formula (I) obtained in Synthesis Example 1 above, 2,5-dichloro-4 ′-(4-phenoxy) phenoxybenzophenone (DCPPB) 35.
9 g (82.5 mmol), bis (triphenylphosphine) nickel dichloride
67 g (2.6 mmol), 1.66 g (11.1 mmol) of sodium iodide, 8.92 g (34.0 mmol) of triphenylphosphine, and 13.3 g (204 mmol) of zinc dust were placed in a flask and purged with dry nitrogen. 160 ml of N-methyl-2-pyrrolidone was added, and the mixture was heated to 80 ° C. and stirred for 4 hours for polymerization. The polymerization solution was diluted with THF, coagulated and recovered with hydrochloric acid / methanol, washed with methanol repeatedly, dissolved in THF, purified by reprecipitation into methanol, and the collected polymer was vacuum-dried to obtain 51.0 g of the desired copolymer. (90%) was obtained. The polystyrene-converted Mn determined by GPC (THF) was 38,900, and Mw was 160,
000.

(Synthesis of polyarylene having a sulfonic acid group)
50 g of the copolymer was placed in a 1000 ml separable flask equipped with a stirrer and a thermometer, 500 ml of sulfuric acid having a concentration of 98% was added, and the mixture was stirred for 24 hours under a nitrogen stream while maintaining the internal temperature at 25 ° C. The obtained solution was poured into a large amount of ion exchange water to precipitate a polymer. The polymer was repeatedly washed until the pH of the wash water reached 5, and then dried to obtain 56 g (95%) of a sulfonic acid group-containing polymer. The Mn in terms of polystyrene determined by GPC of the sulfonic acid group-containing polymer was 45,500, and Mw was 176,000. The sulfonic acid equivalent of the obtained sulfonic acid group-containing polymer was 2.1 meq / g.

[Example 1]
130 g of the polyarylene copolymer having a sulfonic acid group obtained in Synthesis Example 2 is dissolved in a mixed solvent of 218 g of methanol and 652 g of NMP, and the composition has a concentration of 13 wt% (the solution viscosity at room temperature is 7,000 mPa · s). A product was prepared. This solution was applied to a 125 μm thick PET film (Tetron HSL-125, manufactured by Teijin DuPont Co., Ltd.) that was not surface-treated using an INVEX lab coater manufactured by Inoue Metal Industry. This was preliminarily dried at 80 ° C. and further dried at 140 ° C., and punched out into a 20 cm square as a PET film. A-1 and A-2 having film thicknesses of 50 μm and 100 μm after drying were obtained. When the residual solvent of the film A-1, A-2 was measured using a 400MHz ¹ H-NMR, was 44 wt%. The ratio of residual solvent NMP was calculated from the absorption of protons of NMP appearing in the vicinity of about 2.18 ppm.

  The obtained film A-1 was stretched 2.0 times in a uniaxial direction at 140 ° C. using a biaxial stretching machine (manufactured by Toyo Seiki Seisakusho, × 6H-S type). Under the present circumstances, after heat-processing for 60 minutes at 140 degreeC by extending | stretching state, film A-3 was obtained by peeling a PET film. It was 25 micrometers when the film thickness of obtained film A-3 was confirmed. Film A-1 was stretched 2.0 times in the biaxial direction at 140 ° C. Under the present circumstances, after heat-processing for 60 minutes at 140 degreeC by extending | stretching state, film A-4 was obtained by peeling a PET film. It was 26 micrometers when the film thickness of obtained film A-4 was confirmed. Various measurement results and the like of the obtained films A-3 and A-4 are shown in Table 1.

[Example 2]
130 g of the polyarylene copolymer having a sulfonic acid group obtained in Synthesis Example 3 is dissolved in a mixed solvent of 435 g of methanol and 435 g of NMP, and the composition has a concentration of 13% by weight (solution viscosity at room temperature is 5,900 mPa · s). A product was prepared. This solution was applied to a 125 μm thick PET film (Tetron HSL-125, manufactured by Teijin DuPont Co., Ltd.) that was not surface-treated using an INVEX lab coater manufactured by Inoue Metal Industry. This was preliminarily dried at 80 ° C. and further dried at 140 ° C., and punched out into a 20 cm square as a PET film. B-1 and B-2 having film thicknesses of 50 μm and 100 μm after drying were obtained. When the film B-1, the residual solvent in B-2 was measured using a 400MHz ¹ H-NMR, was 30 wt%. The ratio of residual solvent NMP was calculated from the absorption of protons of NMP appearing in the vicinity of about 2.18 ppm.

The obtained film B-1 was stretched 2.0 times in a uniaxial direction at 140 ° C. using a biaxial stretching machine (manufactured by Toyo Seiki Seisakusho, × 6H-S type). Under the present circumstances, after heat-processing for 60 minutes at 140 degreeC by extending | stretching state, film B-3 was obtained by peeling a PET film. When the film thickness of the obtained film B-3 was confirmed, it was 25 μm. Similarly, the film was stretched 2.0 times in the biaxial direction at 140 ° C. Under the present circumstances, after heat-processing for 60 minutes at 140 degreeC by extending | stretching state, film B-4 was obtained by peeling a PET film. It was 24 micrometers when the film thickness of the obtained film B-4 was confirmed. Various measurement results and the like of the obtained films B-3 and B-4 are shown in Table 1.

[Comparative Example 1]
A copolymer (copolymer) having a weight average molecular weight of 150,000 consisting of 4-phenoxybenzoyl-1,4-phenylene repeating unit (A) and diphenylmethanone-4,4′-diyl repeating unit (B). The sulfonated polymer was obtained by sulfonating the combined composition (A) / (B) = 90/10 wt%) with concentrated sulfuric acid. In this sulfonated polymer, 90 mol% of the (A) unit was sulfonated, and the (B) unit was not sulfonated. 150 g of the obtained sulfonated polymer was dissolved in a mixed solvent of 212 g of methanol and 638 g of NMP to prepare a solution having a concentration of 15% by weight. Using this solution, an INVEX lab coater manufactured by Inoue Kinzoku Kogyo Co., Ltd. was applied to a 125 μm thick PET film (Tetron HSL-125, manufactured by Teijin DuPont Co., Ltd.) so that the film thickness after drying would be 28 μm. Applied. This was pre-dried at 80 ° C. for 30 minutes to obtain a film C-1 punched into 20 cm square as a PET film. When the residual solvent of the film C-1 was measured using a 400MHz ¹ H-NMR, was 17 wt%. The ratio of residual solvent NMP was calculated from the absorption of protons of NMP appearing in the vicinity of about 2.18 ppm.

  The obtained film C-1 was stretched 2.0 times in a uniaxial direction at 140 ° C. using a biaxial stretching machine (manufactured by Toyo Seiki Seisakusho Co., Ltd., x6H-S type). Cracks occurred and could not be obtained as a film. This failed film was designated C-2. In the same manner, the film was stretched 1.1 times in the uniaxial direction. Under the present circumstances, after heat-processing for 60 minutes at 140 degreeC by extending | stretching state, film C-3 was obtained by peeling a PET film. When the film thickness of the obtained film C-3 was confirmed, it was 25 micrometers. Various measurement results are shown in Table 1.

Claims (3)

(I) applying a composition comprising polyarylene having a sulfonic acid group and (II) an organic solvent to a substrate;
A method for producing a film, comprising: stretching a substrate coated with the composition in a uniaxial or biaxial direction; and heating the stretched substrate in a stretched state. The polyarylene (I) having the sulfonic acid group includes a repeating unit represented by the following general formula (A) and a repeating unit represented by the following general formula (B). Film manufacturing method.

(In the formula, Y represents a divalent electron-withdrawing group, Z represents a divalent electron-donating group or a direct bond, and Ar represents an aromatic group having a substituent represented by —SO ₃ H. M represents an integer of 0 to 10, n represents an integer of 0 to 10, and k represents an integer of 1 to 4.)

(Wherein R ^{1 to} R ⁸ may be the same or different from each other, and at least one selected from the group consisting of a hydrogen atom, a fluorine atom, an alkyl group, a fluorine-substituted alkyl group, an allyl group, an aryl group, and a cyano group) A seed atom or group, W represents a divalent electron-withdrawing group or a single bond, T represents a single bond or a divalent organic group, and p represents a positive integer of 2 or more.)   The method for producing a film according to claim 1 or 2, wherein a draw ratio in the drawing is 1.01 to 5 times.