JP2008239963A - Process for producing polymer molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide, in view of a background of the conventional art, a process for producing a polymer molded product industrially-advantageous, inexpensive, and excellent in mechanical characteristics and dimensional stability; and a polymer electrolyte part, a membrane electrode composite, and a polymer electrolyte type fuel cell capable of realizing high output, high energy capacity, and long-term durability. <P>SOLUTION: The process for producing a polymer molded product comprises a step of removing at least a part of protective groups contained in the formed molded product. As a constituting unit containing the protective groups, a polymer material containing the constituting unit expressed by general formula (P1) and/or general formula (P2) is molded, and then, the formed molded product is brought into contact with a deprotective treatment solution. The deprotective treatment solution contains at least one deprotective accelerating agent selected from the group consisting of alcohols, alkyl ketones, alkyl aldehydes, and alkyl orthoesters. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  INDUSTRIAL APPLICABILITY The present invention is an industrially advantageous and inexpensive method for producing a polymer molded body having excellent mechanical properties and dimensional stability, and excellent practicality capable of achieving high output, high energy capacity, and long-term durability. The present invention relates to a polymer electrolyte component, a membrane electrode assembly, and a polymer electrolyte fuel cell.

  Aromatic polyketones such as aromatic polyetherketone and aromatic polyetheretherketone have the highest level of heat resistance (continuous use temperature) and heat distortion resistance among thermoplastic resins, and are excellent in flame retardancy and at the time of combustion. It is a crystalline resin with an unprecedented characteristic that it generates very little smoke and corrosive gas. In addition, it has excellent mechanical properties, hot water resistance, radiation resistance, and chemical resistance. These properties are mainly due to the high melting point and high crystallinity.

  However, the high crystallinity of the aromatic polyketone hinders the polymerization and processing of the polymer and is insoluble in typical organic solvents at temperatures preferred for producing the aromatic polyketone, such as temperatures below 250 ° C. It was difficult to increase the molecular weight of the group polyketone. Moreover, even if a high molecular weight aromatic polyketone was obtained, the processing method was limited due to its high melting point and solvent insolubility, and it could not be used in a wide range of applications.

  In order to solve such drawbacks, a method of first synthesizing a polyketal ketone as a high molecular weight amorphous polymer and then producing a high molecular weight crystalline aromatic polyether ketone by deprotection of the ketal group Have been reported (for example, see Patent Document 1, Patent Document 2, and Non-Patent Document 1).

  Patent Document 2 and Non-Patent Document 1 propose a method for reacting polymer powder under pressure conditions of 160 ° C. or higher in the presence of an acid catalyst such as hydrochloric acid or sulfuric acid as a production method for ketal group deprotection. ing. However, this method requires high temperature and pressure in order to increase the conversion rate and quantitatively deprotect, which is not industrially advantageous. Furthermore, in the said literature, only the process of the polymer powder was described, and there was no idea as a method for producing a polymer molded body in which deprotection was performed after molding.

Further, Patent Document 3 proposes a method for producing a molded polymer electrolyte containing an ionic group, and the deprotection conditions include treatment at 95 ° C. and 6N aqueous hydrochloric acid for 24 hours. However, treatment with high temperature and high concentration acidic aqueous solution has not been an industrially advantageous method.
Japanese Patent Publication No. 02-14334 Japanese Patent Publication No. 02-1844 JP 2006-261103 A “Macromolecules”, 1987, vol. 20, p.1204.

  In view of the background of such prior art, the present invention achieves an industrially advantageous and inexpensive method for producing a polymer molded body having excellent mechanical properties and dimensional stability, as well as high output, high energy capacity, and long-term durability. It is an object of the present invention to provide a polymer electrolyte part, a membrane electrode assembly, and a polymer electrolyte fuel cell that are excellent in practical use.

  The present invention employs the following means in order to solve the above problems. That is, the method for producing a polymer molded body of the present invention includes a step of molding a polymer material containing a structural unit represented by the following general formula (P1) and / or (P2) as a structural unit containing a protecting group. And a method of producing a polymer molded body having a step of contacting the deprotection solution with at least a part of the protecting group, wherein the deprotection solution is an alcohol, an alkyl ketone, an alkyl aldehyde. And at least one deprotection accelerator selected from alkyl orthoesters.

(In the general formulas (P1) and (P2), A _{1 to} A ₄ are any divalent organic group, R ₁ and R ₂ are at least one group selected from H and an alkyl group, and R ₃ is any And E represents O or S, each of which may represent two or more groups, and the structural units represented by the general formulas (P1) and (P2) may be optionally substituted. )
The polymer electrolyte component, membrane electrode assembly, and polymer electrolyte fuel cell of the present invention are characterized by using such a method for producing a polymer molded body.

  INDUSTRIAL APPLICABILITY According to the present invention, a method for producing a polymer molded body that is industrially advantageous and inexpensive, excellent in mechanical properties and dimensional stability, and practicality capable of achieving high output, high energy capacity, and long-term durability. It is possible to provide a polymer electrolyte component, a membrane electrode assembly, and a polymer electrolyte fuel cell excellent in the above.

  Hereinafter, the present invention will be described in detail.

  The present invention has been intensively studied on the above-mentioned problem, that is, a method for producing a polymer molded body that is industrially advantageous and inexpensive, and has excellent mechanical properties and dimensional stability. As a structural unit containing a protecting group, the following general formula ( A polymer that deprotects at least a part of the protecting group after the step of molding the polymer material containing the structural unit represented by P1) and / or (P2) and then contacting the deprotection solution A method for producing a molded article, wherein the deprotection treatment solution contains at least one deprotection accelerator selected from alcohols, alkyl ketones, alkyl aldehydes, and alkyl orthoesters. It was clarified to solve the problem.

(In the general formulas (P1) and (P2), A _{1 to} A ₄ are any divalent organic group, R ₁ and R ₂ are at least one group selected from H and an alkyl group, and R ₃ is any And E represents O or S, each of which may represent two or more groups, and the structural units represented by the general formulas (P1) and (P2) may be optionally substituted. )
Examples of the polymer molded body of the present invention include films (including films and films), plates, fibers, hollow fibers, particles, lumps, micropores, coatings, foams, and the like. It can take various forms depending on the intended use. The polymer can be applied to a wide range of applications because it can improve the design freedom of the polymer and various properties such as mechanical properties and solvent resistance. In particular, it is suitable when the polymer molded body is a polymer electrolyte molded body containing an ionic group, and when the polymer molded body is a membrane. Hereinafter, the case of a polymer film will be described.

  Aromatic polyetherketone (PEK) -based polymers exhibit crystallinity because of their good packing and extremely strong intermolecular cohesive strength, and have the property of not dissolving in general solvents at all. In contrast, the polymer molding obtained by the present invention reduces the crystallinity of a crystalline polymer such as a PEK polymer, which has been difficult to form in the past, by including a protective group in the polymer. By adding the solubility, it is possible to use it for film formation. Furthermore, after being formed into a film or the like, the molecular chain of the polymer is improved in packing, and at least a part of the protective group is deprotected in order to impart intermolecular cohesive force and crystallinity again. It provides a polymer membrane with significantly improved solvent resistance such as methanol and dimensional stability, tensile strength and elongation, mechanical properties such as tear strength and fatigue resistance, and fuel barrier properties such as methanol and hydrogen. However, when the production process of the present invention is performed, in particular, the polymer film obtained by the present invention is compatible with the production cost, dimensional stability, mechanical properties, and solvent resistance in addition to the film formability (workability). Have Further, when used as a polymer electrolyte membrane, in addition to the above characteristics, it is possible to achieve both proton conductivity, fuel barrier properties, and long-term durability against swelling and shrinkage.

  In the present invention, a protecting group is a substituent that is temporarily introduced on the assumption that it will be removed at a later stage, protecting a highly reactive functional group and making it inert to the subsequent reaction. It can be deprotected after the reaction and returned to the original functional group. That is, it is a pair with a functional group to be protected. For example, a t-butyl group may be used as a protective group for a hydroxyl group, but when the same t-butyl group is introduced into an alkylene chain, It is not called a protecting group. The reaction for introducing a protecting group is called protection (reaction), and the reaction for removal is called deprotection (reaction). In the present invention, the stage for introducing a protecting group may be selected from a monomer stage, an oligomer stage, or a polymer stage, and can be appropriately selected.

  The protection reaction used in the present invention includes a method of protecting / deprotecting a ketone moiety with an acetal or ketal moiety in terms of reactivity and stability, a heteroatom analog of the ketone moiety with an acetal or ketal moiety, such as thioacetal. And a structural unit containing a protecting group contains at least one selected from the above general formulas (P1) and (P2).

Among them, in the general formulas (P1) and (P2), E is O in terms of the odor, reactivity, stability, etc. of the compound, that is, the ketone moiety is protected / deprotected with an acetal or ketal moiety. The method is more preferred. Furthermore, in the present invention, R ₁ and R ₂ in the general formula (P1) are more preferably an alkyl group from the viewpoint of stability, more preferably an alkyl group having 1 to 6 carbon atoms, most preferably carbon. It is a C 1-3 alkyl group. Moreover, as R < ₃ > in general formula (P2), it is more preferable that it is a C1-C7 alkylene group from a stability point, Most preferably, it is a C1-C4 alkylene group. Specific examples of R ₃ include —CH ₂ CH ₂ —, —CH (CH ₃ ) CH ₂ —, —CH (CH ₃ ) CH (CH ₃ ) —, —C (CH ₃ ) ₂ CH ₂ —, —C. _{(CH 3) 2 CH (CH} 3) -, - C (CH 3) 2 O (CH 3) 2 -, - CH 2 CH 2 CH 2 -, - CH 2 C (CH 3) 2 CH 2 - and the like However, it is not limited to these.

As the polymer molded body containing at least a protecting group used in the present invention, among the structural units of the general formula (P1) or (P2), at least the general formula (from the viewpoint of stability such as hydrolysis resistance). Those having P2) are more preferably used. Furthermore, R _{3 in the} general formula (P2) is preferably an alkylene group having 1 to 7 carbon atoms, that is, a group represented by C _n1 H _2n1 (n1 is an integer of 1 to 7). From the viewpoint of ease of synthesis, it is most preferably at least one selected from —CH ₂ CH ₂ —, —CH (CH ₃ ) CH ₂ —, or —CH ₂ CH ₂ CH ₂ —.

Preferred organic groups as A _{1 to} A ₄ in the general formulas (P1) and (P2) are a phenylene group, a naphthylene group, or a biphenylene group. These may be optionally substituted. As the aromatic polyether polymer of the present invention, A ₃ and A ₄ in the general formula (P2) are both phenylene groups from the viewpoint of solubility and availability of raw materials, that is, the following general formula (P3) it is more preferable to contain in a structural unit represented by, most preferably a ₃ and a ₄ are both p- phenylene.

(In General Formula (P3), n1 is an integer of 1 to 7. The structural unit represented by General Formula (P3) may be optionally substituted.)
The method for producing a polymer molded body of the present invention comprises a polymer molded body containing a structural unit represented by the following general formula (P1) and / or (P2), a deprotection treatment solution containing a deprotection accelerator, By carrying out the reaction, the reaction proceeds uniformly even under mild conditions, and a high conversion can be obtained with a short reaction time. If it is a manufacturing method of this invention, even if it is a polymer of a solid state, such as a polymer molding, it is possible to achieve a high conversion rate under mild conditions.

  Further, the method for producing a polymer molded body of the present invention can reduce the production cost because the reaction time required for conversion is short and the reaction can be performed at a low temperature. In addition, due to the low-temperature and low-concentration acid treatment, the manufacturing cost can be greatly reduced by continuous roll-to-roll production, which was difficult with the prior art that required high-temperature treatment at 95 ° C. or higher. Furthermore, corrosion of production equipment due to the use of high-temperature and high-concentration hydrochloric acid is prevented, and processing in an open system is possible, so that manufacturing costs can be reduced by simplifying equipment.

  The deprotection accelerator used in the present invention needs to be at least one selected from alcohols, alkyl ketones, alkyl aldehydes, and alkyl orthoesters from the viewpoint of reactivity.

  When the polymer material used in the present invention has a structural unit represented by the following general formula (P2), it can be converted from a cyclic ketal to an acyclic ketal by reacting with an alcohol or an alkyl orthoester. It is possible to increase the conversion rate or relax the conditions. In addition, by reacting with alkyl ketones and alkyl aldehydes, it is possible to exchange protecting groups on the alkyl ketones and alkyl aldehydes side, so it is possible to increase the conversion rate and relax the conditions. .

  In the case where the polymer material used in the present invention has a structural unit represented by the following general formula (P1), at least selected from alcohols, alkyl ketones, alkyl aldehydes, and alkyl orthoesters. By using one kind, it is possible to increase the conversion rate or relax the conditions. Of these, alkyl orthoesters are more preferable in terms of conversion.

  Specific examples of alkyl orthoesters include trimethyl orthoformate, triethyl orthoformate, trimethyl orthoacetate, triethyl orthoacetate, tetramethyl orthosilicate, tetraethyl orthosilicate, 2,2-dimethoxypropane, 2,2-dimethyl- 1,3-dioxolane and the like can be mentioned. In terms of conversion rate and cost, trimethyl orthoformate, triethyl orthoformate, trimethyl orthoacetate and triethyl orthoacetate are more preferred, and trimethyl orthoformate is most preferred.

  Specific examples of alcohols include methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, t-butyl alcohol, n-pentyl alcohol, 2-methyl-1-butanol, 3-pentanol, n -C1-C6 alcohols, such as hexyl alcohol, are mentioned, More preferably, they are methanol, ethanol, and isopropyl alcohol at a conversion rate, cost, and a hydrophilic point.

  Specific examples of the alkyl ketones include alkyl ketones having 1 to 6 carbon atoms such as acetone, methyl ethyl ketone, diethyl ketone, dipropyl ketone and the like, and acetone which is lower in terms of conversion rate, cost, and hydrophilicity is more preferable. preferable.

  Specific examples of the alkyl aldehydes include alkyl aldehydes having 1 to 6 carbon atoms such as formaldehyde, acetaldehyde, propionaldehyde and the like. Moreover, as these deprotection promoters, two or more selected from the above may be used together.

  The content of the deprotection accelerator contained in the deprotection treatment solution used in the present invention is 0.1 wt% or more and 50 wt% or less with respect to the whole deprotection treatment solution in terms of conversion rate and cost. More preferably, it is more preferably 1 wt% or more and 40 wt% or less, and most preferably 3 wt% or more and 35 wt% or less. When the content is less than 0.1 wt%, the reaction time becomes long and a high conversion rate may not be obtained. In addition, when it exceeds 50 wt%, the cost may increase, side reactions may occur, the reaction time may be long, or a high conversion rate may not be obtained.

  The deprotection treatment solution used in the present invention more preferably contains a strong acid as an acid catalyst in terms of shortening the reaction time and conversion rate. Specific examples of the strong acid used include hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, benzenesulfonic acid, xylenesulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, trifluoroacetic acid and the like. Of these, hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, and benzenesulfonic acid are more preferable in terms of conversion rate and cost. Of these, sulfuric acid is most preferable from an industrial viewpoint. Two or more strong acids selected from the above may be used together.

  As the deprotection treatment solution used in the present invention, when a solution containing an alkyl orthoester and an aqueous solution containing a strong acid are used, these may be used in combination. In consideration of decomposition, it is also preferable to treat with an alkyl orthoester and then with an aqueous solution containing a strong acid.

  The treatment temperature of the deprotection solution used in the present invention is more preferably 0 ° C. or higher and 80 ° C. or lower, more preferably 20 ° C. or higher and 40 ° C. or lower in terms of production cost and conversion rate. When the treatment temperature is less than 0 ° C. or exceeds 80 ° C., the production cost increases, which is not preferable.

  Next, the polymer material used in the present invention will be described. The polymer material containing at least a protecting group used in the present invention is more preferably a polymer having an aromatic ring in the main chain among hydrocarbon polymers from the viewpoint of mechanical strength and chemical stability. The main chain structure is not particularly limited as long as it has an aromatic ring, but preferably has a sufficient mechanical strength to be used, for example, as an engineering plastic. Further, the present invention is particularly suitable for producing a polymer film exhibiting crystallinity.

  Specific examples of the polymer having an aromatic ring in the main chain used in the present invention include polysulfone, polyethersulfone, polyphenylene oxide, polyarylene ether-based polymer, polyphenylene sulfide, polyphenylene sulfide sulfone, polyparaphenylene, polyarylene-based polymer, At least one of components such as polyarylene ketone, polyether ketone, polyarylene phosphine oxide, polyether phosphine oxide, polybenzoxazole, polybenzthiazole, polybenzimidazole, polyamide, polyimide, polyetherimide, polyimidesulfone, etc. The polymer containing is mentioned. Polysulfone, polyethersulfone, polyetherketone, and the like referred to here are generic names for polymers having a sulfone bond, an ether bond, and a ketone bond in the molecular chain thereof. Polyetherketoneketone, polyetheretherketone, It includes polyether ether ketone ketone, polyether ketone ether ketone ketone, polyether ketone sulfone and the like, and does not limit the specific polymer structure.

  Among the polymers having an aromatic ring in the main chain, polysulfone, polyethersulfone, polyphenylene oxide, polyarylene ether-based polymer, polyphenylene sulfide, polyphenylene sulfide sulfone, polyarylene ketone, polyether ketone, polyarylene phosphine oxide, poly A polymer such as ether phosphine oxide is more preferable from the viewpoint of mechanical strength, processability and hydrolysis resistance.

  Specifically, a polymer containing an aromatic group in the main chain having a repeating unit represented by the following general formula (T1) can be given.

(Here, Z ¹ and Z ² each represent an organic group containing an aromatic ring, and each may represent two or more groups. At least one of Z ¹ and Z ² is ionic.) Y ¹ represents an electron-withdrawing group, Y ² represents O or S. a and b each independently represent 0 or a positive integer, provided that a and b are not 0 at the same time.)
Among the polymers containing aromatic groups in the main chain having the repeating unit represented by the general formula (T1), the polymers having the repeating units represented by the general formula (T1-1) to the general formula (T1-6) are resistant to It is more preferable in terms of hydrolyzability, mechanical strength and production cost. Among them, from the viewpoint of mechanical strength and production cost, an aromatic polyether polymer in which Y ² is O is more preferable, and most preferably has a repeating unit represented by the general formula (T1-3), that is, Aromatic polyether ketone polymers are most preferred.

(Here, Z ¹ and Z ² each represent an organic group containing an aromatic ring, and each may represent two or more groups. At least one of Z ¹ and Z ² is ionic.) A and b each independently represents 0 or a positive integer, provided that a and b are not 0 at the same time.)
Preferred organic groups as Z ¹ are a phenylene group and a naphthylene group. These may be substituted.

Preferred examples of the organic group represented by R ^p in the general formula (T1-4) include a methyl group, an ethyl group, a propyl group, an isopropyl group, a cyclopentyl group, a cyclohexyl group, a norbornyl group, a vinyl group, an allyl group, and a benzyl group. A phenyl group, a naphthyl group, a phenylphenyl group, and the like. From the viewpoint of industrial availability, the most preferable R ^p is a phenyl group.

  In the present invention, the aromatic polyether-based polymer refers to a polymer mainly composed of an aromatic ring and containing an ether bond as a mode in which the aromatic ring units are connected. In addition to the ether bond, there may be a bond mode generally used for forming an aromatic polymer such as a direct bond, ketone, sulfone, sulfide, various alkylenes, imides, amides, esters, and urethanes. The ether bond is preferably at least one per repeating unit of the main constituent component. The aromatic ring may include not only a hydrocarbon aromatic ring but also a hetero ring. Further, a part of the aliphatic units may constitute a polymer together with the aromatic ring unit. Aromatic units include hydrocarbon groups such as alkyl groups, alkoxy groups, aromatic groups, allyloxy groups, halogen groups, nitro groups, cyano groups, amino groups, halogenated alkyl groups, carboxyl groups, phosphonic acid groups, hydroxyl groups, etc. And may have an arbitrary substituent.

  Even when the aromatic polyether polymer contains a bonding mode other than an ether bond such as a direct bond, the position of the protective group to be introduced is the aromatic ether polymer part from the viewpoint of improving processability. Is more preferable.

  The method for producing a polymer molded body of the present invention is particularly suitable when the polymer material contains an ionic group together with a protective group, that is, a polymer electrolyte material. In general, a polymer electrolyte material containing an ionic group is usually not thermoplastic or has low heat resistance, so that it is difficult to mold after deprotecting the protective group. If it is the manufacturing method of the polymeric molded object of this invention, it shape | molds in the state containing a protective group, A protective group is deprotected after shaping | molding, It can be set as an insoluble and infusible polymeric molded object.

  The ionic group in the polymer may be introduced by block copolymerization or random copolymerization. It can be appropriately selected depending on the chemical structure of the polymer used and the high crystallinity. Random copolymerization is more preferable when fuel barrier properties and low water content are required, and block copolymerization is more preferably used when proton conductivity and high water content are required.

  The ionic group used in the present invention is not particularly limited as long as it is a negatively charged atomic group, but is preferably one having proton exchange ability. As such a functional group, a sulfonic acid group, a sulfonimide group, a sulfuric acid group, a phosphonic acid group, a phosphoric acid group, and a carboxylic acid group are preferably used. Here, the sulfonic acid group is a group represented by the following general formula (f1), the sulfonimide group is a group represented by the following general formula (f2) [in the general formula, R represents an arbitrary atomic group. The sulfuric acid group is represented by the following general formula (f3), the phosphonic acid group is represented by the following general formula (f4), and the phosphoric acid group is represented by the following general formula (f5) or (f6). And the carboxylic acid group means a group represented by the following general formula (f7).

Such ionic groups include cases where the functional groups (f1) to (f7) are salts. Examples of the cation forming the salt include an arbitrary metal cation, NR ₄ ⁺ (R is an arbitrary organic group), and the like. In the case of a metal cation, the valence and the like are not particularly limited and can be used. Specific examples of preferable metal ions include Li, Na, K, Rh, Mg, Ca, Sr, Ti, Al, Fe, Pt, Rh, Ru, Ir, and Pd. Among these, Na and K, which are inexpensive and do not adversely affect the solubility and can be easily proton-substituted, are more preferably used as the polymer electrolyte membrane.

  Two or more kinds of these ionic groups can be contained in the polymer electrolyte membrane, and may be preferable by combining them. The combination is appropriately determined depending on the structure of the polymer. Among them, it is more preferable to have at least a sulfonic acid group, a sulfonimide group, and a sulfuric acid group from the viewpoint of high proton conductivity, and most preferable to have at least a sulfonic acid group from the viewpoint of hydrolysis resistance.

  The amount of sulfonic acid groups in the polymer electrolyte membrane can be expressed as a value of sulfonic acid group density (mmol / g). The sulfonic acid group density of the polymer electrolyte membrane in the present invention is preferably 0.1 to 5.0 mmol / g, more preferably 0.5 to 5.0 in terms of proton conductivity, fuel crossover and mechanical strength. 2.5 mmol / g, most preferably 0.8 to 2.0 mmol / g from the point of fuel crossover. When the sulfonic acid group density is lower than 0.1 mmol / g, sufficient proton generation characteristics may not be obtained due to low proton conductivity. When the sulfonic acid group density is higher than 5.0 mmol / g, it may be used as an electrolyte membrane for a fuel cell. In addition, sufficient water resistance and mechanical strength when containing water may not be obtained.

  Here, the sulfonic acid group density is the number of moles of sulfonic acid groups introduced per gram of the dried polymer electrolyte membrane, and the larger the value, the greater the amount of sulfonic acid groups. The sulfonic acid group density can be determined by elemental analysis or neutralization titration. Among these, it is preferable to calculate from the S / C ratio using an elemental analysis method for ease of measurement. However, when a sulfur source other than a sulfonic acid group is included, the ion exchange capacity is obtained by a neutralization titration method. You can also The polyelectrolyte material of the present invention includes an embodiment in which the polymer electrolyte material has a complex composed of a polymer having an ionic group and other components, as will be described later. In this case, the sulfonic acid group density is based on the total amount of the complex. Suppose that

The procedure for neutralization titration is as follows. The measurement shall be performed three times or more and the average shall be taken.
(1) The sample is pulverized by a mill, and in order to make the particle diameter uniform, the sample is passed through a 50-mesh mesh sieve and the sample passed through the sieve is used as the measurement sample.
(2) Weigh the sample tube (with lid) with a precision balance.
(3) About 0.1 g of the sample of (1) is put into a sample tube and vacuum dried at 40 ° C. for 16 hours.
(4) Weigh the sample tube with the sample and determine the dry weight of the sample.
(5) Dissolve sodium chloride in a 30 wt% aqueous methanol solution to prepare a saturated saline solution.
(6) Add 25 mL of the saturated salt solution of (5) above to the sample and stir for 24 hours for ion exchange.
(7) Titrate the resulting hydrochloric acid with 0.02 mol / L aqueous sodium hydroxide. Two drops of a commercially available titration phenolphthalein solution (0.1% by volume) as an indicator are added, and the point at which light reddish purple is obtained is the end point.
(8) The sulfonic acid group density is determined by the following formula.

Sulfonic acid group density (mmol / g) =
[Concentration of sodium hydroxide aqueous solution (mmol / ml) × Drip amount (ml)] / Dry weight of sample (g)
The polymer having an ionic group used in the present invention is not limited to the purpose of the present invention, and other components such as an inert polymer or an organic or inorganic compound having no conductivity or ionic conductivity, May be contained.

  Examples of a method for introducing an ionic group into an aromatic polyether polymer include a method of polymerizing using a monomer having an ionic group and a method of introducing an ionic group by a polymer reaction.

  As a method of polymerizing using a monomer having an ionic group, a monomer having an ionic group in a repeating unit may be used, and if necessary, an appropriate protecting group may be introduced to perform a deprotecting group after polymerization. . Such a method is described, for example, in Journal of Membrane Science, 197, 2002, p.231-242.

  The method of introducing an ionic group in a polymer reaction will be described with an example. For example, introduction of a phosphonic acid group into an aromatic polymer is described in Polymer Preprints, 51, 2002, p.750, etc. This is possible by the method described. Introduction of a phosphate group into an aromatic polymer can be achieved by, for example, phosphoric esterification of an aromatic polymer having a hydroxyl group. Introduction of a carboxylic acid group into an aromatic polymer can be performed by oxidizing an aromatic polymer having an alkyl group or a hydroxyalkyl group, for example. Introduction of a sulfate group into an aromatic polymer can be achieved by, for example, sulfate esterification of an aromatic polymer having a hydroxyl group.

  As a method for sulfonating an aromatic polymer, that is, a method for introducing a sulfonic acid group, for example, a method described in JP-A-2-16126 or JP-A-2-208322 is known. Specifically, for example, an aromatic polymer can be sulfonated by reacting with a sulfonating agent such as chlorosulfonic acid in a solvent such as chloroform, or by reacting in concentrated sulfuric acid or fuming sulfuric acid. . The sulfonating agent is not particularly limited as long as it sulfonates an aromatic polymer, and sulfur trioxide or the like can be used in addition to the above. When the aromatic polymer is sulfonated by this method, the degree of sulfonation can be easily controlled by the amount of the sulfonating agent used, the reaction temperature and the reaction time. Introduction of a sulfonimide group into an aromatic polymer can be achieved, for example, by a method of reacting a sulfonic acid group and a sulfonamide group.

  The method for synthesizing the aromatic polyether polymer used in the present invention is not particularly limited as long as it is a method capable of substantially increasing the molecular weight. For example, the aromatic active dihalide compound and 2 It can be synthesized using an aromatic nucleophilic substitution reaction of a polyhydric phenol compound or an aromatic nucleophilic substitution reaction of a halogenated aromatic phenol compound.

  Specifically, for example, aromatic polyether polymers containing the structural units represented by the general formulas (P1) and (P2) are represented by the following general formulas (P1-1) and ( It is possible to synthesize by an aromatic nucleophilic substitution reaction with an aromatic active dihalide compound using the compound represented by P2-1). The structural units represented by the general formulas (P1) and (P2) may be derived from either the divalent phenol compound or the aromatic active dihalide compound, but the divalent phenol is considered in consideration of the reactivity of the monomer. More preferably derived from a compound.

(In the general formulas (P1-1) and (P2-1), Ar _{1 to} Ar ₄ are any divalent arylene group, R ₁ and R ₂ are at least one group selected from H and an alkyl group, R ₃ represents an arbitrary alkylene group, and E represents O or S. The compounds represented by the general formula (P1-1) and the general formula (P2-1) may be optionally substituted.
Specific examples of particularly preferred dihydric phenol compounds used in the present invention include compounds represented by the following general formulas (r1) to (r10), and derivatives derived from these dihydric phenol compounds.

  Among these dihydric phenol compounds, the compounds represented by the general formulas (r4) to (r10) are more preferable from the viewpoint of stability, and more preferably the compounds represented by the general formulas (r4), (r5), and (r9). The compound represented by the general formula (r4) is most preferred.

  When the amount of the protecting group contained in the polymer molded product obtained by the present invention is large, since it has solvent solubility, nuclear magnetic resonance spectrum (NMR) is suitable for quantification of the protecting group. However, if the amount of protecting group is very small and insoluble in the solvent, it may be difficult to accurately quantify by NMR. In such a case, the generated gas analysis by temperature-programmed thermal desorption-mass spectrometry (TPD-MS), pyrolysis gas chromatograph, or pyrolysis GC-MS is a suitable quantitative method.

For example, when the polymer molding obtained by the present invention contains the general formula (P2) as a structural unit and R ₃ is —CH ₂ CH ₂ —, the temperature-programmed thermal desorption-mass spectrometry method ( At least C ₂ H ₄ O gas and / or C ₄ H ₈ O ₂ gas is detected by the evolved gas analysis by TPD-MS).

In the amount of gas generated in the polymer molded body obtained by the present invention, the total amount of C ₂ H ₄ O generated gas and C ₄ H ₈ O ₂ generated gas is 20% by weight with respect to the dry weight of the polymer molded body. The following is more preferable. The polymer material for molding is more preferably 1% by weight or more and 20% by weight or less from the viewpoint of solvent solubility. On the other hand, when the polymer molded product obtained in the present invention requires mechanical properties, it is more preferably 1% by weight or less, further preferably 0.3% by weight or less, most preferably 0.8%. 1% by weight or less.

  The quantitative determination of the ketal group content by the TPD-MS method of the polymer electrolyte material of the present invention is performed by the following method. That is, the generated gas analysis at the time of heating is performed on the polymer electrolyte material as a specimen under the conditions described in the examples.

  The aromatic active dihalide compound is not particularly limited as long as it can have a high molecular weight by an aromatic nucleophilic substitution reaction with a dihydric phenol compound. More preferable specific examples of the aromatic active dihalide compound include 4,4′-dichlorodiphenyl sulfone, 4,4′-difluorodiphenyl sulfone, 4,4′-dichlorodiphenyl ketone, 4,4′-difluorodiphenyl ketone, 4,4′-dichlorodiphenylphenylphosphine oxide, 4,4′-difluorodiphenylphenylphosphine oxide, 2,6-dichlorobenzonitrile, 2,6-difluorobenzonitrile and the like can be mentioned. Among these, 4,4′-dichlorodiphenyl ketone and 4,4′-difluorodiphenyl ketone are more preferable in terms of imparting crystallinity, mechanical strength, heat-resistant methanol property, and fuel crossover suppressing effect, and 4,4 ′ from the viewpoint of polymerization activity. -Difluorodiphenyl ketone is most preferred. These aromatic active dihalide compounds can be used alone, but a plurality of aromatic active dihalide compounds can also be used in combination.

  As the aromatic polyether polymer used in the present invention, monomers having an ionic group exemplified by those having a structural unit represented by the following general formula (P5) are also preferably used. It is preferable to use a compound in which an ionic acid group is introduced into an aromatic active dihalide compound as a monomer because the amount of the ionic group can be precisely controlled. Examples of monomers having sulfonic acid groups as ionic groups include 3,3′-disulfonate-4,4′-dichlorodiphenylsulfone, 3,3′-disulfonate-4,4′-difluorodiphenylsulfone, 3 3,3′-disulfonate-4,4′-dichlorodiphenyl ketone, 3,3′-disulfonate-4,4′-difluorodiphenyl ketone, 3,3′-disulfonate-4,4′-dichlorodiphenylphenylphosphine And oxide, 3,3′-disulfonate-4,4′-difluorodiphenylphenylphosphine oxide, and the like.

  In terms of proton conductivity and hydrolysis resistance, a sulfonic acid group is most preferable as an ionic group, but the monomer having an ionic group used in the present invention may have another ionic group. . Among these, 3,3′-disulfonate-4,4′-dichlorodiphenyl ketone and 3,3′-disulfonate-4,4′-difluorodiphenyl ketone are more preferable from the viewpoint of heat resistance methanol resistance and fuel crossover suppression effect. From the viewpoint of polymerization activity, 3,3′-disulfonate-4,4′-difluorodiphenyl ketone is most preferred.

(In General Formula (P5), M ¹ and M ² represent hydrogen, a metal cation, an ammonium cation, and a 1 and a 2 each represent an integer of 1 to 4. The structural unit represented by General Formula (P5) is further optionally substituted. May be.)
When an aromatic polyether polymer is obtained by an aromatic nucleophilic substitution reaction of an aromatic active dihalide compound and a divalent phenol compound, at least the general formula (P1-1) and / or the divalent phenol compound is obtained. Although it is necessary to use what is represented by (P2-1), it is also possible to use other dihydric phenol compounds together. As the dihydric phenol compound to be copolymerized, various dihydric phenol compounds that can be used for the polymerization of an aromatic polyether polymer by an aromatic nucleophilic substitution reaction can be used. Absent. Moreover, what introduce | transduced the sulfonic acid group into these aromatic dihydroxy compounds can also be used as a monomer.

  In the present invention, the dihydric phenol compound used in combination with the dihydric phenol compound represented by the general formula (P1-1) and / or (P2-1) is not particularly limited, and processability, crystal Can be selected as appropriate in consideration of properties, fuel cutoff, mechanical strength, and the like.

  Preferable specific examples of the dihydric phenol used in combination include divalent phenol compounds represented by the following general formulas (X-1) to (X-6) from the viewpoint of a group capable of improving crystallinity. Due to the improvement in crystallinity, the resulting polymer molded body can be preferably used because it can exhibit performances excellent in mechanical properties, solvent resistance, fuel blocking properties, long-term durability, and the like.

(The groups represented by the general formulas (X-1) to (X-6) may be optionally substituted, but do not include an ionic group.)
In the polymerization by the aromatic nucleophilic substitution reaction, a polymer can be obtained by reacting the monomer mixture in the presence of a basic compound. The polymerization reaction can be carried out in the temperature range of 0 to 350 ° C, but is preferably 50 to 250 ° C. When the temperature is lower than 0 ° C., the reaction does not proceed sufficiently, and when the temperature is higher than 350 ° C., the polymer tends to be decomposed.

  Such a polymerization reaction can be carried out in the absence of a solvent, but is preferably carried out in a solvent. Use N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, diphenylsulfone, sulfolane, 1,3-dimethyl-2-imidazolidinone as the solvent. However, it is not limited to these, and any solvent that can be used as a stable solvent in the aromatic nucleophilic substitution reaction may be used. These organic solvents may be used alone or as a mixture of two or more.

  Examples of the basic compound used for the polymerization by the aromatic nucleophilic substitution reaction include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate and the like. Any material can be used as long as it can have a phenoxide structure. In the aromatic nucleophilic substitution reaction to be reacted in the presence of such a basic compound, water may be generated as a by-product. In this case, toluene or the like can coexist in the reaction system, and water can be removed from the system as an azeotrope. As a method for removing water out of the system, a water-absorbing agent such as molecular sieve can also be used.

  When this aromatic nucleophilic substitution reaction is carried out in a solvent, it is preferable to charge the monomer so that the resulting polymer concentration is 5 to 50% by weight. When the polymer concentration is less than 5% by weight, the degree of polymerization tends to be difficult to increase. On the other hand, when the polymer concentration is more than 50% by weight, the reaction system becomes too viscous and post-treatment of the reaction product is difficult. Tend to be. After completion of the polymerization reaction, the solvent is removed from the reaction solution by evaporation, and the residue is washed as necessary to obtain the desired polymer. In addition, the polymer can be obtained by precipitating the polymer as a solid by adding the reaction solution in a solvent having low polymer solubility, and collecting the precipitate by filtration.

  The weight average molecular weight of the aromatic polyketal polymer by GPC method is preferably 10,000 to 1,000,000, more preferably 100,000 to 600,000. If the weight average molecular weight is less than 10,000, the mechanical properties may be insufficient. On the other hand, if it exceeds 1,000,000, the processability may be inferior.

  The polymer molded body obtained by the present invention can be particularly preferably used as a polymer electrolyte part for a fuel cell. The polymer electrolyte component in the present invention means a component containing a polymer electrolyte molded body and a polymer electrolyte material. In the present invention, the shape of the polymer electrolyte component is the same as that of the aforementioned polymer molded body.

  When the polymer molded body obtained by the present invention is used for a fuel cell, it is suitable for a membrane state and a catalyst layer binder. In addition, an additive such as a plasticizer, a stabilizer or a mold release agent used in ordinary polymer compounds is added to the polymer molded body obtained by the present invention within a range not violating the purpose of the present invention. be able to. In addition, various polymers, elastomers, fillers, fine particles, various additives, etc. may be included for the purpose of improving mechanical strength, thermal stability, processability, etc. within the range that does not adversely affect various properties. Good.

  There is no particular limitation on the method of converting the polymer electrolyte material used in the present invention into a membrane, but a method of forming a film from a solution state or a method of forming a film from a molten state is possible at a stage having a protective group such as ketal. It is. In the former, for example, the polymer electrolyte material is dissolved in a solvent such as N-methyl-2-pyrrolidone, the solution is cast on a glass plate or the like, and the solvent is removed to form a film. It can be illustrated.

  The solvent used for film formation is not particularly limited as long as the polymer electrolyte material can be dissolved and then removed. For example, N, N-dimethylacetamide, N, N-dimethylformamide, N-methyl-2-pyrrolidone , Aprotic polar solvents such as dimethyl sulfoxide, sulfolane, 1,3-dimethyl-2-imidazolidinone, hexamethylphosphontriamide, ester solvents such as γ-butyrolactone and butyl acetate, carbonates such as ethylene carbonate and propylene carbonate Solvent, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, alkylene glycol monoalkyl ether such as propylene glycol monoethyl ether, or isopropanol Alcohol solvents, water and mixtures thereof is preferably used, is preferred for high highest solubility aprotic polar solvent.

  As a specific example of the method for converting the polymer electrolyte material used in the present invention into a membrane, a membrane composed of the aromatic polyether polymer is prepared by the above-described method, and then at least one of the ketone sites protected with a ketal is used. The part is deprotected to form a ketone moiety. This method makes it possible to form a solution of a low sulfonic acid group polymer with poor solubility, achieving both proton conductivity and a fuel crossover suppression effect, excellent solvent resistance, mechanical properties, and dimensional stability. It becomes possible.

  The film thickness of the polymer electrolyte membrane of the present invention is preferably 1 to 2000 μm. A thickness of more than 1 μm is more preferable for obtaining the strength of a film that can withstand practical use, and a thickness of less than 2000 μm is preferable for reducing film resistance, that is, improving power generation performance. A more preferable range of the film thickness is 3 to 500 μm, and a particularly preferable range is 5 to 250 μm. The film thickness can be controlled by the solution concentration or the coating thickness on the substrate.

  The polymer electrolyte molded body obtained by the present invention means a molded body containing the polymer electrolyte material of the present invention. In the present invention, specific shapes of the molded body include, in addition to membranes (including films and films), plates, fibers, hollow fibers, particles, lumps, microporous, coatings, It can take various forms depending on the intended use, such as foams. The polymer can be applied to a wide range of applications because it can improve the design freedom of the polymer and various properties such as mechanical properties and solvent resistance. It is particularly suitable when the polymer electrolyte molded body is a membrane. When the polymer electrolyte material of the present invention is used for a fuel cell, it is particularly suitable for a membrane state and a catalyst layer binder.

  The polymer electrolyte material used in the present invention can be applied to various uses. For example, it can be applied to medical applications such as extracorporeal circulation columns and artificial skin, applications for filtration, ion exchange resin applications, various structural materials, and electrochemical applications. It is also suitable as an artificial muscle. Among these, it can be preferably used for various electrochemical applications. Examples of the electrochemical application include a fuel cell, a redox flow battery, a water electrolysis device, a chloroalkali electrolysis device, and the like, among which the fuel cell is most preferable. Further, among fuel cells, it is suitable for a polymer electrolyte fuel cell, which includes those using hydrogen as a fuel and those using an organic compound such as methanol as a fuel. It is particularly preferably used for a direct fuel cell using at least one selected from a mixture of water and water as fuel. As the organic compound having 1 to 6 carbon atoms, alcohols having 1 to 3 carbon atoms such as methanol, ethanol and isopropyl alcohol, and dimethyl ether are preferable, and methanol is most preferably used.

  The membrane electrode composite of the present invention means a membrane electrode composite containing the polymer electrolyte material of the present invention in a polymer electrolyte membrane or a catalyst layer. Furthermore, the membrane electrode composite is a component in which a polymer electrolyte membrane and an electrode are combined.

  There is no particular limitation on the method of joining the polymer electrolyte membrane and the electrode when using such a polymer electrolyte membrane as a fuel cell, and a known method (for example, a chemical plating method described in Electrochemistry, 1985, 53, p.269. , Applied Electrochemical Society (J. Electrochem. Soc.), Electrochemical Science and Technology, 1988, 135, 9, p.2209. Is possible.

  Among the fuel cells, it is suitable for a polymer electrolyte fuel cell, and there are those using hydrogen as a fuel and those using an organic compound such as methanol as a fuel. It is particularly preferably used for a direct fuel cell using at least one selected from a mixture of water as fuel. As the organic compound having 1 to 6 carbon atoms, alcohols having 1 to 3 carbon atoms such as methanol, ethanol and isopropyl alcohol, and dimethyl ether are preferable, and methanol is most preferably used.

  Fuels for fuel cells using the membrane electrode assembly of the present invention include oxygen, hydrogen and methane, ethane, propane, butane, methanol, isopropyl alcohol, acetone, glycerin, ethylene glycol, formic acid, acetic acid, dimethyl ether, hydroquinone, cyclohexane Examples thereof include organic compounds having 1 to 6 carbon atoms and mixtures of these with water, and may be one kind or a mixture of two or more kinds. In particular, a fuel containing hydrogen and an organic compound having 1 to 6 carbon atoms is preferably used from the viewpoint of power generation efficiency and simplification of the entire battery system, and hydrogen and aqueous methanol are particularly preferable in terms of power generation efficiency.

  In the case of using an aqueous methanol solution, the concentration of methanol is appropriately selected depending on the fuel cell system to be used, but a concentration as high as possible is preferable from the viewpoint of long-time driving. For example, an active fuel cell having a system for sending a medium necessary for power generation, such as a liquid feed pump or a blower fan, to a membrane electrode assembly, or an auxiliary machine such as a cooling fan, a fuel dilution system, or a product recovery system has a methanol concentration of 30. It is preferable to inject ~ 100% or more of fuel with a fuel tank or fuel cassette, dilute it to about 0.5 to 20% and send it to the membrane electrode assembly. A passive fuel cell without auxiliary equipment has a methanol concentration Is preferable in the range of 10 to 100%.

  Furthermore, the application of the polymer electrolyte fuel cell of the present invention is not particularly limited, but a power supply source for a mobile body is preferable. In particular, mobile devices such as mobile phones, personal computers, PDAs, televisions, radios, music players, game machines, headsets, DVD players, human-type and animal-type robots for industrial use, home appliances such as cordless vacuum cleaners, and toys , Electric bicycles, motorcycles, automobiles, buses, trucks and other vehicles and ships, power supplies for mobiles such as railways, stationary primary generators such as stationary generators, or alternatives to these It is preferably used as a hybrid power source.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these. In addition, the measurement conditions of each physical property are as follows. Further, a chemical structural formula is inserted in this example, and the chemical structural formula is inserted for the purpose of helping the reader to understand. The chemical structure of the polymerization component of the polymer, the exact composition, the arrangement, the sulfonic acid The position, number, molecular weight, and the like of the group are not necessarily expressed accurately, and are not limited thereto.

(1) Weight average molecular weight The weight average molecular weight of the polymer was measured by GPC. Tosoh's HLC-8022GPC is used as an integrated unit of an ultraviolet detector and a differential refractometer, and Tosoh's TSK gel SuperHM-H (inner diameter 6.0 mm, length 15 cm) is used as the GPC column. -Measured with a pyrrolidone solvent (N-methyl-2-pyrrolidone solvent containing 10 mmol / L of lithium bromide) at a flow rate of 0.2 mL / min, and the weight average molecular weight was determined in terms of standard polystyrene.

(2) Nuclear magnetic resonance spectrum (NMR)
Under the following measurement conditions, ¹ H-NMR is measured to confirm the structure and to determine the mixing ratio of 4,4′-dihydroxybenzophenone and 2,2-bis (4-hydroxyphenyl) -1,3-dioxolane. It was. The mixing ratio (mol%) is a peak observed at 7.6 ppm (derived from 4,4′-dihydroxybenzophenone) and 7.2 ppm (derived from 2,2-bis (4-hydroxyphenyl) -1,3-dioxolane). Calculated from the integrated value.

Apparatus: EX-270 manufactured by JEOL Ltd.
Resonance frequency: 270 MHz ( ¹ H-NMR)
Measurement temperature: room temperature Dissolving solvent: DMSO-d6
Internal reference material: TMS (0 ppm)
Accumulation count: 16 times Further, solid ¹³ C-CP / MAS spectrum was measured under the following measurement conditions, and the presence or absence of a ketal group was confirmed.

Apparatus: CMX-300 Infinity manufactured by Chemagnetics
Measurement temperature: Room temperature Internal reference material: Si rubber (1.56ppm)
Measurement nucleus: 75.188829 MHz
Pulse width: 90 ° pulse, 4.5 μsec
Pulse repetition time: ACQTM = 0.03413sec, PD = 9sec
Spectrum width: 30.003 kHz
Sample rotation: 7 kHz
Contact time: 4msec
(3) Analysis of residual amount of ketal group (TPD-MS measurement)
The polymer electrolyte material as a specimen is analyzed for gas generated during heating under the following conditions, and C ₂ H ₄ O (m / z = 29) and 2-methyl-1,3-dioxolane (m / z = 73) ) To determine the remaining amount (wt%) of the ketal group.
A. Equipment used
TPD-MS equipment <Main specifications>
Heating unit: TRC heating device (electric heater type heating furnace, quartz glass reaction tube)
MS Department: Shimadzu GC / MS QP5050A
B. Test conditions Heating temperature conditions: Room temperature to 550 ° C (Temperature increase rate 10 ° C / min)
Atmosphere: He flow (50mL / min) (Iwatani Corp., purity 99.995%)
C. Sample Amount of sample used: about 1.5mg
Pretreatment: vacuum drying at 80 ° C. for 180 minutes Standard sodium tungstate dihydrate (H ₂ O standard sample): Sigma Aldrich, special grade 99%
1-butene (organic component standard sample): GL science, 7.92% / N ₂ balance Carbon dioxide: GL science, 99.9%
Sulfur dioxide: Sumitomo Seika, 1.000% / N ₂ balance Phenol: Wako Pure Chemicals, special grade 99.0%
2-methyl-1,3-dioxolane (C ₂ H ₄ O, etc. and 2-methyl-1,3-dioxolane standard sample): Tokyo Chemical Industry, special grade 98%
E. Measurement room temperature (room temperature range)
23 ± 2 ℃
(4) Analysis of residual amount of ketal group (solid ¹³ C-DD / MAS spectrum)
Apparatus: CMX-300 Infinity manufactured by Chemagnetics
Measurement: DD / MAS method, relaxation time mode Observation nucleus: ¹³ C
Internal reference material: Si rubber (1.56ppm)
Observation frequency: 75.4977791 MHz, 10.0.6248425 MHz
Pulse width: 4.2 μsec, 3.3 μsec
Pulse repetition time: PD: 150 s, 10 s
Spectrum width: 30.003 kHz
Sample rotation: 9 kHz, 14 kHz
Measurement temperature: room temperature (5) Methanol permeation amount A membrane-shaped sample was immersed in pure water at 25 ° C. for 24 hours, and then measured at 20 ° C. using a 1 mol% aqueous methanol solution.

A sample membrane was sandwiched between the H-type cells, and pure water (60 mL) was placed in one cell, and 1 mol% aqueous methanol solution (60 mL) was placed in the other cell. The cell capacity was 80 mL each. Moreover, the opening area between cells was 1.77 cm < ² >. Both cells were stirred at 20 ° C. The amount of methanol eluted in pure water at the time of 1 hour, 2 hours and 3 hours was measured and quantified with a gas chromatography (GC-2010) manufactured by Shimadzu Corporation. The methanol permeation amount per unit time was determined from the slope of the graph.

Synthesis example 1
2,2-bis (4-hydroxyphenyl) -1,3-dioxolane represented by the following general formula (G1) was synthesized.

  Montmorillonite clay K10 (750 g) and 4,4′-dihydroxybenzophenone (495 g) were reacted in ethylene glycol (1200 mL) / trimethyl orthoformate (500 mL) at a bath temperature of 110 ° C. while distilling the produced by-products. After 8 hours, 500 mL of trimethyl orthoformate was added and reacted for a total of 16 hours. 1 L of ethyl acetate was added to the reaction solution, and after filtration, extraction was performed 4 times with a 2% aqueous sodium hydrogen carbonate solution. Further, after the concentration, the resulting slurry compound was washed with dichloroethane, whereby a 2,2-bis (4-hydroxyphenyl) -1,3-dioxane / 4,4′-dihydroxybenzophenone mixture (= 85. 5 / 14.5 mol%).

Synthesis example 2
2,2-bis (4-hydroxyphenyl) -1,3-dioxolane represented by the general formula (G1) was synthesized.
In a 500 ml flask equipped with a stirrer, thermometer and distillation tube, 49.5 g of 4,4′-dihydroxybenzophenone, 134 g of ethylene glycol, 96.9 g of trimethyl orthoformate and 0.50 g of p-toluenesulfonic acid monohydrate were added. Charge and dissolve. Thereafter, the mixture was stirred while maintaining at 78 to 82 ° C. for 2 hours. Further, the internal temperature was gradually raised to 120 ° C. and heated until the distillation of methyl formate, methanol, and trimethyl orthoformate completely stopped. After cooling this reaction liquid to room temperature, the reaction liquid was diluted with ethyl acetate, the organic layer was washed with 100 ml of 5% aqueous potassium carbonate solution and separated, and then the solvent was distilled off. Crystals were precipitated by adding 80 ml of dichloromethane to the residue, filtered and dried to obtain 52.0 g of 2,2-bis (4-hydroxyphenyl) -1,3-dioxolane. GC analysis of the crystals revealed 99.8% 2,2-bis (4-hydroxyphenyl) -1,3-dioxolane and 0.2% 4,4'-dihydroxybenzophenone.

Synthesis example 3
Disodium 3,3′-disulfonate-4,4′-difluorobenzophenone represented by the following general formula (G2) was synthesized.

109.1 g (Aldrich reagent) of 4,4′-difluorobenzophenone was reacted at 150 ° C. for 10 hours in 150 mL of fuming sulfuric acid (50 wt% SO ₃ ) (Wako Pure Chemicals reagent). Thereafter, the mixture was poured little by little into a large amount of water, neutralized with NaOH, and 200 g of sodium chloride was added to precipitate the composite. The resulting precipitate was filtered off and recrystallized with an aqueous ethanol solution to obtain disodium 3,3′-disulfonate-4,4′-difluorobenzophenone represented by the above general formula (G2). The purity was 99.3%. The structure was confirmed by ¹ H-NMR. Impurities were quantitatively analyzed by capillary electrophoresis (organic matter) and ion chromatography (inorganic matter).

Synthesis example 4
A polymer represented by the following general formula (G3) was synthesized.
(In the general formula, * represents that the right end of the upper general formula and the left end of the lower general formula are bonded at that position.)

6.91 g of potassium carbonate, 10.23 g of the 2,2-bis (4-hydroxyphenyl) -1,3-dioxane mixture obtained in Synthesis Example 1, 6.11 g of 4,4′-difluorobenzophenone, and the above synthesis example Polymerization was performed at 230 ° C. in N-methylpyrrolidone (NMP) using 5.24 g of disodium 3,3′-disulfonate-4,4′-difluorobenzophenone obtained in 2. Purification was performed by re-precipitation with a large amount of water to obtain a polymer electrolyte material represented by the above general formula (G3). The weight average molecular weight was 330,000. The obtained polymer electrolyte material was subjected to quantitative analysis of the ketal group-derived substance by TPD-MS measurement. As a result, C ₂ H ₄ O and the like were found to be 4.65 wt% per 250 ° C., and 2-methyl-1,3-dioxolane. Of 2.91 wt%, a total of 7.56 wt% of ketal group-derived substances were detected.

  A 25 wt% N-methylpyrrolidone (NMP) solution in which the obtained polymer electrolyte material containing at least a protecting group and an ionic group of the general formula (G3) was dissolved was cast-coated on a glass substrate, and 100 ° C. And dried for 4 hours at 300 ° C. for 10 minutes under nitrogen to obtain a film.

Synthesis example 5
A polymer represented by the general formula (G3) was synthesized.

6.91 g of potassium carbonate, 10.23 g of 2,2-bis (4-hydroxyphenyl) -1,3-dioxane obtained in Synthesis Example 2, 6.11 g of 4,4′-difluorobenzophenone, and Synthesis Example 2 Polymerization was carried out at 230 ° C. in N-methylpyrrolidone (NMP) using 5.17 g of disodium 3,3′-disulfonate-4,4′-difluorobenzophenone obtained in 1 above. Purification was performed by re-precipitation with a large amount of water to obtain a polymer electrolyte material represented by the above general formula (G3). The weight average molecular weight was 400,000. The obtained polymer electrolyte material was subjected to quantitative analysis of the ketal group-derived substance by TPD-MS measurement. As a result, 5.71 wt% of C ₂ H ₄ O, etc. per 250 ° C., 2-methyl-1,3-dioxolane Of 3.13 wt%, a total of 8.84 wt% of ketal group-derived substances were detected.

  A 25 wt% N-methylpyrrolidone (NMP) solution in which the obtained polymer electrolyte material containing at least a protecting group and an ionic group of the general formula (G3) was dissolved was cast-coated on a glass substrate, and 100 ° C. And dried for 4 hours at 300 ° C. for 10 minutes under nitrogen to obtain a film.

Synthesis Example 6
A polymer represented by the general formula (G4) was synthesized.
(In the general formula, * represents that the right end of the upper general formula and the left end of the lower general formula are bonded at that position.)

6.91 g of potassium carbonate, 10.23 g of 2,2-bis (4-hydroxyphenyl) -1,3-dioxane obtained in Synthesis Example 2, 5.24 g of 4,4′-difluorobenzophenone, and Synthesis Example 2 Polymerization was performed at 230 ° C. in N-methylpyrrolidone (NMP) using 6.89 g of disodium 3,3′-disulfonate-4,4′-difluorobenzophenone obtained in 1 above. Purification was performed by re-precipitation with a large amount of water to obtain a polymer electrolyte material represented by the above general formula (G3). The weight average molecular weight was 400,000. The obtained polymer electrolyte material was subjected to quantitative analysis of the ketal group-derived substance by TPD-MS measurement. As a result, 4.64 wt% of C ₂ H ₄ O, etc. Of 3.85 wt%, a total of 8.49 wt% of ketal group-derived substances were detected.

  The obtained 25 wt% N-methylpyrrolidone (NMP) solution in which a polymer electrolyte material containing at least a protecting group and an ionic group of the general formula (G4) was dissolved was cast-coated on a glass substrate, and 100 ° C. And dried for 4 hours at 300 ° C. for 10 minutes under nitrogen to obtain a film.

Synthesis example 7
A polymer represented by the following general formula (G5) was synthesized.

Using 6.91 g of potassium carbonate, 10.23 g of the 2,2-bis (4-hydroxyphenyl) -1,3-dioxane mixture obtained in Synthesis Example 1, and 8.73 g of 4,4′-difluorobenzophenone, N Polymerization was carried out at 230 ° C. in methylpyrrolidone (NMP). Purification was performed by re-precipitation with a large amount of water to obtain a polymer electrolyte material represented by the above general formula (G4). The weight average molecular weight was 200,000. Quantitative analysis of the ketal group-derived substance by TPD-MS measurement of the obtained polymer electrolyte material was conducted. As a result, 5.23 wt% of C ₂ H ₄ O, etc. per 250 ° C., 2-methyl-1,3-dioxolane Of 4.85 wt% and a total of 10.08 wt% of ketal group-derived substances were detected.

  The obtained 25 wt% N-methylpyrrolidone (NMP) solution in which a polymer electrolyte material containing at least a protecting group and an ionic group of the general formula (G5) was dissolved was cast-coated on a glass substrate, and 100 ° C. And dried for 4 hours at 300 ° C. for 10 minutes under nitrogen to obtain a film.

Example 1
The polymer molded body (G3) obtained in Synthesis Example 4 was immersed in an aqueous solution containing 10 wt% of trimethyl orthoformate in 1N hydrochloric acid at 40 ° C. (weight ratio of 1000 times or more with respect to the polymer molded body) for 24 hours. After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

The obtained polymer molded body was subjected to quantitative analysis of the ketal group derived materials by TPD-MS measurement of, _C 2 _{H 4} O such that 0.67Wt% per 250 ° C., 2-methyl-1,3 Ketal group-derived substances with a total of 0.70 wt% of dioxolane, 0.03 wt%, were detected, and the conversion was 90.7 mol%.
The obtained membrane had a thickness of 30 μm, proton conductivity A per area of 5.0 S / cm ² , and MCO of 0.77 μmol / min · cm ² . High conductivity and excellent fuel cutoff. Even when immersed in NMP at 100 ° C., it did not dissolve and was excellent in solvent resistance. Moreover, even if it was bent, it was not broken and was a very tough film.

Example 2
The polymer molded body (G3) obtained in Synthesis Example 5 was immersed in an aqueous solution containing 10 wt% of trimethyl orthoformate in 1N hydrochloric acid at 40 ° C. (weight ratio of 1000 times or more with respect to the polymer molded body) for 24 hours. After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

Quantitative analysis of the ketal group-derived substance by TPD-MS measurement of the obtained polymer molding was conducted. As a result, 0.83 wt% of C ₂ H ₄ O, etc. per 250 ° C., 2-methyl-1,3-dioxolane Of 0.04 wt% and a total of 0.87 wt% of ketal group-derived substances were detected, and the conversion was 90.2 mol%.

Example 3
The polymer molded body (G3) obtained in Synthesis Example 5 was immersed in an aqueous solution containing 10 wt% of trimethyl orthoformate in 1N hydrochloric acid at 60 ° C. (weight ratio of 1000 times or more with respect to the polymer molded body) for 24 hours. After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

Quantitative analysis of the ketal group-derived substance by TPD-MS measurement of the obtained polymer molding was conducted. As a result, 0.63 wt% of C ₂ H ₄ O and the like, and methyl 2-methyl-1,3-dioxolane per 250 ° C. Of 0.07 wt% and a total of 0.70 wt% of ketal group-derived substances were detected and the conversion was 92.1 mol%.

Example 4
The polymer molded body (G3) obtained in Synthesis Example 5 was immersed in an aqueous solution containing 30 wt% trimethyl orthoformate in 1N hydrochloric acid at 40 ° C. (weight ratio of 1000 times or more with respect to the polymer molded body) for 24 hours. After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

Quantitative analysis of the ketal group-derived substance by TPD-MS measurement of the obtained polymer molding was performed. As a result, 0.34 wt% of C ₂ H ₄ O, etc. However, 0.04 wt% and a total of 0.38 wt% of ketal group-derived substances were detected, and the conversion was 95.7 mol%.

Example 5
The polymer molded body (G3) obtained in Synthesis Example 5 was immersed in an aqueous solution containing 30 wt% of trimethyl orthoformate in 3N hydrochloric acid (weight ratio of 1000 times or more with respect to the polymer molded body) at 40 ° C. for 24 hours. After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

  When the obtained polymer molding was quantitatively analyzed for the ketal group-derived substance by TPD-MS measurement, the ketal group-derived substance was not detected.

Example 6
The polymer molded body (G3) obtained in Synthesis Example 5 was immersed in an aqueous solution containing 10 wt% of acetone in 1N hydrochloric acid at 40 ° C. (weight ratio of 1000 times or more with respect to the polymer molded body) for 24 hours for proton substitution. After the deprotection reaction, it was immersed in a large excess amount of pure water for 24 hours and sufficiently washed to obtain a polymer molded body.

Quantitative analysis of the ketal group-derived substance by TPD-MS measurement of the obtained polymer molding was performed. As a result, 0.88 wt% of C ₂ H ₄ O, etc. per 250 ° C., 2-methyl-1,3-dioxolane Was found to be a total of 0.93 wt% of ketal group-derived substances, and the conversion was 89.5 mol%.

Example 7
The polymer molding (G3) obtained in Synthesis Example 5 was immersed in an aqueous solution containing 10 wt% of acetaldehyde in 1N hydrochloric acid at 40 ° C. (weight ratio of 1000 times or more with respect to the polymer molding) for 24 hours to perform proton substitution. After the deprotection reaction, it was immersed in a large excess amount of pure water for 24 hours and sufficiently washed to obtain a polymer molded body.

When the obtained polymer molding was quantitatively analyzed for the substance derived from the ketal group by TPD-MS measurement, 0.95 wt% of C ₂ H ₄ O, etc. per 250 ° C., 2-methyl-1,3-dioxolane Of 0.07 wt% and a total of 1.02 wt% of ketal group-derived substances were detected and the conversion was 88.5 mol%.

Example 8
The polymer molded body (G3) obtained in Synthesis Example 5 is immersed in an aqueous solution containing 10 wt% of methanol in 1N hydrochloric acid at 40 ° C. (weight ratio of 1000 times or more with respect to the polymer molded body) for 24 hours to perform proton substitution After the deprotection reaction, it was immersed in a large excess amount of pure water for 24 hours and sufficiently washed to obtain a polymer molded body.

Quantitative analysis of the ketal group-derived substance by TPD-MS measurement of the obtained polymer molding was conducted. As a result, 0.92 wt% of C ₂ H ₄ O, etc. per 250 ° C., 2-methyl-1,3-dioxolane Of 0.07 wt% and a total of 0.99 wt% of ketal group-derived substances were detected, and the conversion was 88.8 mol%.

Example 9
The polymer molding (G4) obtained in Synthesis Example 6 was immersed in an aqueous solution containing 10 wt% trimethyl orthoformate in 1N hydrochloric acid at 40 ° C. (weight ratio of 1000 times or more with respect to the polymer molding) for 24 hours. After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

Quantitative analysis of the ketal group-derived substance by TPD-MS measurement of the obtained polymer molding was performed. As a result, 0.77 wt% of C ₂ H ₄ O, etc. per 250 ° C., 2-methyl-1,3-dioxolane Of 0.04 wt% and a total of 0.81 wt% of ketal group-derived substances were detected, and the conversion was 90.5 mol%.

Example 10
The polymer molded body (G5) obtained in Synthesis Example 7 was immersed in an aqueous solution containing 10 wt% trimethyl orthoformate in 1N hydrochloric acid at 40 ° C. (weight ratio of 1000 times or more with respect to the polymer molded body) for 24 hours. After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

The obtained polymer molding was quantitatively analyzed for the substance derived from the ketal group by TPD-MS measurement. As a result, 0.90 wt% of C ₂ H ₄ O, etc. was obtained per 250 ° C., and 2-methyl-1,3-dioxolane. Of 0.07 wt% and a total of 0.97 wt% of ketal group-derived substances were detected, and the conversion was 90.4 mol%.

Example 11
The polymer molded body (G4) obtained in Synthesis Example 6 was immersed in an aqueous solution containing 10 wt% of trimethyl orthoformate in 1 M sulfuric acid at 40 ° C. (weight ratio of 1000 times or more with respect to the polymer molded body) for 1 hour. After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

When quantitative analysis of the ketal group-derived substance by solid ¹³ C-DD / MAS spectrum measurement of the obtained polymer molding was performed, 7 mol% of the C ₂ H ₄ peak of the ketal group was detected per 65 ppm, and the conversion rate was 93 It was 0.0 mol%.

Example 12
The polymer molded body (G4) obtained in Synthesis Example 6 was immersed at 60 ° C. in an aqueous solution containing 10 wt% trimethyl orthoformate in 1 M sulfuric acid (weight ratio of 1000 times or more with respect to the polymer molded body) for 1 hour. After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

When quantitative analysis of the ketal group-derived substance by solid ¹³ C-DD / MAS spectrum measurement of the obtained polymer molding was performed, 5 mol% of the C ₂ H ₄ peak of the ketal group was detected per 65 ppm, and the conversion rate was 95. It was 0.0 mol%.

Example 13
The polymer molded body (G4) obtained in Synthesis Example 6 was immersed at 80 ° C. in an aqueous solution containing 10 wt% trimethyl orthoformate in 1 M sulfuric acid (weight ratio of 1000 times or more with respect to the polymer molded body) for 24 hours. After the proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess of pure water for 1 hour and thoroughly washing.

When quantitative analysis of the ketal group-derived substance by solid ¹³ C-DD / MAS spectrum measurement of the obtained polymer molding was performed, 3 mol% of the C ₂ H ₄ peak of the ketal group was detected per 65 ppm, and the conversion rate was 97. It was 0.0 mol%.

Example 14
The polymer molded body (G4) obtained in Synthesis Example 6 was immersed in an aqueous solution containing 10 wt% of trimethyl orthoformate in 3M sulfuric acid at 60 ° C. (weight ratio of 1000 times or more with respect to the polymer molded body) for 1 hour. After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

When quantitative analysis of the ketal group-derived substance by solid ¹³ C-DD / MAS spectrum measurement of the obtained polymer molding was performed, 3 mol% of the C ₂ H ₄ peak of the ketal group was detected per 65 ppm, and the conversion rate was 97. It was 0.0 mol%.

Example 15
The polymer molded body (G4) obtained in Synthesis Example 6 was immersed at 60 ° C. for 1 hour in an aqueous solution containing 30 wt% of trimethyl orthoformate in 3M sulfuric acid (weight ratio of 1000 times or more with respect to the polymer molded body). After proton substitution and deprotection reaction, the polymer molded body was obtained by immersing in a large excess amount of pure water for 24 hours and thoroughly washing.

When quantitative analysis of the substance derived from the ketal group by solid ¹³ C-DD / MAS spectrum measurement of the obtained polymer molded body was performed, 2 mol% of the C ₂ H ₄ peak of the ketal group was detected per 65 ppm, and the conversion rate was 98. It was 0.0 mol%.

Comparative Example 1
After the polymer molded body (G3) obtained in Synthesis Example 5 was immersed in 1N hydrochloric acid at 40 ° C. for 24 hours to perform proton substitution and deprotection, it was immersed in a large excess amount of pure water for 24 hours and thoroughly washed. A polymer molding was obtained.

In the obtained polymer molded body, in the solid ¹³ C-CP / MAS spectrum, peaks of chemical shifts of about 65 ppm and about 110 ppm (derived from ketal group) recognized in the film before deprotection are obtained after deprotection. Quantitative analysis of the ketal group-derived material by TPD-MS measurement of the electrolyte membrane revealed that C ₂ H ₄ O and the like were 1.11 wt% and 2-methyl-1,3-dioxolane was 0.03 wt% per 250 ° C. A total of 1.14 wt% of ketal group-derived substances was detected, and the conversion was 87.1 mol%. Compared with Example 4 to which trimethyl orthoformate was added, the conversion rate was low, and the amount of the remaining ketal group was 12.9%, which was about 3 times higher.

Comparative Example 2
The polymer molded body (G3) obtained in Synthesis Example 5 was immersed in 6N hydrochloric acid at 95 ° C. for 24 hours to perform proton substitution and deprotection, and then immersed in a large excess amount of pure water for 24 hours to be thoroughly washed. A polymer molding was obtained.

When the obtained polymer molding was quantitatively analyzed for the substance derived from the ketal group by TPD-MS measurement, 0.24 wt% of C ₂ H ₄ O, etc. per 250 ° C., 2-methyl-1,3-dioxolane Of 0.05 wt% and a total of 0.29 wt% of ketal group-derived substances were detected, and the conversion was 96.7 mol%. Although the conversion rate is high, it is difficult to reduce the production cost because the reaction vessel or the like is corroded unless it is completely sealed.

Comparative Example 3
The polymer molded body (G4) obtained in Synthesis Example 6 was immersed in 1M sulfuric acid at 60 ° C. for 1 hour to perform proton substitution and deprotection reaction, and then immersed in a large excess amount of pure water for 24 hours to be thoroughly washed. A polymer molding was obtained.

When quantitative analysis of the ketal group-derived substance by solid ¹³ C-DD / MAS spectrum measurement of the obtained polymer molding was performed, 7 mol% of the C ₂ H ₄ peak of the ketal group was detected per 65 ppm, and the conversion rate was 93 It was 0.0 mol%.

Claims (8)

As the structural unit containing a protecting group, after the step of molding a polymer material containing the structural unit represented by the following general formula (P1) and / or (P2), the step of contacting with a deprotection solution A method for producing a polymer molded body in which at least a part of a protecting group is deprotected, wherein the deprotection solution is at least one kind selected from alcohols, alkyl ketones, alkyl aldehydes, and alkyl orthoesters. A method for producing a polymer molded body comprising a protection accelerator.

(In the general formulas (P1) and (P2), A _{1 to} A ₄ are any divalent organic group, R ₁ and R ₂ are at least one group selected from H and an alkyl group, and R ₃ is any And E represents O or S, each of which may represent two or more groups, and the structural units represented by the general formulas (P1) and (P2) may be optionally substituted. ) The manufacturing method of the polymer molded object of Claim 1 which contains the structural unit represented by the following general formula (P3) as a structural unit containing this protective group.

(N1 in General Formula (P3) is an integer of 1 to 7. The structural unit represented by General Formula (P3) may be optionally substituted.) The method for producing a polymer molded body according to claim 1, wherein the content of the deprotection accelerator contained in the deprotection treatment solution is 0.1 wt% or more and 50 wt% or less. The method for producing a polymer molded body according to any one of claims 1 to 3, wherein the deprotection solution further contains a strong acid. The method for producing a polymer molded body according to any one of claims 1 to 4, wherein the deprotection solution is brought into contact at 0 ° C or higher and 80 ° C or lower. The method for producing a polymer molded body according to any one of claims 1 to 5, wherein the polymer material is an aromatic polyether ketone polymer. The method for producing a polymer molded body according to any one of claims 1 to 6, wherein the polymer material contains an ionic group. The method for producing a polymer molded body according to any one of claims 1 to 7, wherein the polymer molded body is a polymer electrolyte part for a fuel cell.