WO2011156935A1

WO2011156935A1 - Proton exchange membrane, preparation process and use thereof

Info

Publication number: WO2011156935A1
Application number: PCT/CN2010/000893
Authority: WO
Inventors: 张永明; 唐军柯; 刘萍; 张恒; 王军
Original assignee: 山东东岳神舟新材料有限公司
Priority date: 2010-06-18
Filing date: 2010-06-18
Publication date: 2011-12-22

Abstract

A proton exchange membrane (PEM), preparation process and use in PEM fuel cell thereof are provided. The PEM comprises 2-40 layers of mono-layer membrane in which perfluoro ion exchange resins serve as the substrate. In the PEM, at least one layer of the mono-layer membrane has crosslinked network structure; at least one layer of the mono-layer membrane contains surface-modified auxiliary proton transmitter; at least one layer of the mono-layer membrane comprises high-valence metal compounds; and at least one layer of the mono-layer membrane is modified micro-porous membrane. By using modified micro-porous membrane, chemically bonded crosslink, and the physically bonded crosslink formed between high-valence metal compounds and acidic exchange groups, the proton transmitting property and mechanical strength of the said PEM are greatly improved.

Description

Proton exchange membrane and preparation method and application thereof

The invention relates to a proton exchange membrane and a preparation method and application thereof. Background technique

The proton exchange membrane fuel cell (PEMFC) is a power generation device that directly converts chemical energy into electrical energy by electrochemical means. It is considered to be the clean, efficient power generation technology of choice in the 21st century. Proton exchange membrane (PEM) is a key material for proton exchange membrane fuel cells.

The perfluorosulfonic acid proton exchange membranes currently used have good proton conductivity at lower temperatures (not higher than 8 (TC) and higher humidity, but there are also many disadvantages such as poor dimensional stability and mechanical strength. High, poor chemical stability, etc.

The water absorption of the film at different humidity levels and the dimensional expansion due to water absorption are different. When the film is changed under different working conditions, the size of the film will also change, and the repetition will eventually lead to mechanical breakage of the proton exchange membrane. In addition, the positive electrode reaction of a fuel cell often generates a large amount of highly oxidizing substances such as hydroxyl radicals and hydrogen peroxide, which attack the non-fluorine groups in the film-forming resin molecules, resulting in chemical degradation or damage of the film. Foaming. In addition, high operating temperatures can greatly improve the carbon monoxide resistance of fuel cell catalysts, but when the operating temperature of the perfluorosulfonic acid exchange membrane is higher than 90 °C, the proton conductivity of the membrane drops sharply due to the rapid dehydration of the membrane. Thereby the efficiency of the fuel cell is greatly reduced. In addition, the existing perfluorosulfonic acid membranes have a certain hydrogen or methanol permeability, especially in a direct methanol fuel cell, and the methanol permeability is very large, which is a fatal problem. Therefore, how to improve the strength and dimensional stability of the perfluorosulfonic acid proton exchange membrane and the proton conductivity at high temperatures and reduce the permeability of the working medium are major issues facing the fuel cell industry.

Some methods have been proposed to solve these problems. For example, JP-B-5-75835 uses a perfluorosulfonic acid resin to impregnate a porous medium made of polytetrafluoroethylene (PTFE) to enhance the strength of the film. However, this porous medium of PTFE has not completely solved the above problems because the PTFE material is relatively soft and the reinforcing effect is insufficient. The Gore-Select series of composite membrane liquids developed by WL Gore uses a porous Teflon-filled Nafion ion conductive liquid (US 5,547,551, US 5,653,041 and US 5,599,614), which has high proton conductivity and large Dimensional stability, but Teflon creeps at high temperatures, resulting in reduced performance. JP-B-7-68377 also proposes a method of filling a porous medium made of polyolefin with a proton exchange resin, but having insufficient chemical durability and thus long-term stability There are problems in qualitative aspects; and because of the addition of porous media that do not have proton conductivity, the proton conduction pathway is reduced and the proton exchange capacity of the membrane is reduced. Further, JP-A-6-231779 proposes another reinforcing method using fluororesin fibers. The mechanical strength of the fluorocarbon polymer reinforcement in the form of fibrils. However, this method requires the addition of a relatively large amount of reinforcing material. In this case, the processing of the film tends to be difficult, and the increase in film resistance is likely to occur. In US 5,834,523, Ballard Corporation impregnates a solution of sulfonated α,β,β-trifluorostyrenesulfonic acid with m-trifluoromethyl-α , β , β-trifluorostyrene in methanol/propanol The pores of the swollen porous PTFE membrane were then dried at 50 ° C to obtain a composite membrane. However, it needs to be repeated several times to fully fill the polymer into the pores of the PTFE microporous membrane.

In WO 98/51733, a 25 μη thick sulfonyl fluoride type membrane is passed together with a Gore PTFE membrane by hot pressing at 31 (TC vacuum). The membrane is then hydrolyzed in a KOH solution of dimethyl sulfoxide. , the -S0 ₂ F group in the film was converted to -S0 ₃ -. Finally, a 5% sulfonic acid resin solution was applied three times on one side of the porous PTFE film, and the film was made into a whole in 15 (TC vacuum oven). The method is too time consuming and the microporous membrane is difficult to fill with sulfonic acid resin.

Porous film reinforcement tends to have a phase separation between the reinforcing body and the film-forming resin, and there is a large gap, resulting in a film having a high gas permeability.

Crosslinking can improve the thermal stability of the polymer, reduce the swelling of the solvent, and increase the mechanical strength of the polymer. It has been widely used in the fields of separation and adsorption and various rubber elastomers. At present, many cross-linking techniques have also been explored to solve the problems of perfluorosulfonic acid proton exchange membranes. For example, us 20070031715 describes a crosslinking method in which sulfonyl chloride crosslinks to form a sulfonyl anhydride, and the sulfonyl anhydride crosslinked structure formed in the method can effectively improve the mechanical strength of the film, but the crosslinked structure has obvious disadvantages. The sulfonamide unit is unstable to the base. However, US 20030032739 achieves the purpose of crosslinking by linking a sulfonyl group on a polymer chain to a thiol group between molecular chains. This crosslinking can well reduce the solvent swellability of the film. However, many steps are required to obtain the crosslinked structure, which is not suitable for the industrialization process. US 6733914 discloses a melt-extruded perfluorosulfonyl fluoride membrane immersed in aqueous ammonia to form a sulfonimide crosslinked proton exchange membrane, and the treated perfluorosulfonic acid membrane has good mechanical strength and dimensional stability. However, the membrane obtained by this method is a non-uniform membrane because the ammonia gas enters the membrane by the permeation method, and the ammonia gas reacts with the sulfonyl fluoride during the permeation process, and the reacted sulfonyl fluoride will prevent the ammonia gas from further moving toward the membrane. The diffusion inside the film forms a high crosslink density on the surface of the film, and almost no cross-linking occurs inside the film. The large cross-linking of the surface causes the conductivity of the film to drop sharply.

The perfluorosulfonic acid film containing a triazine ring crosslinked structure disclosed in US Pat. No. 7,259,208 and CN 101029144 (Application No. 200710013624.7, respectively) also has good mechanical strength and dimensional stability. But Membranes that are crosslinked by chemical bonding alone often fail to form a high degree of crosslinking and have limited performance in improving the film. The properties of the final film did not meet the requirements for use.

In order to improve the high-temperature proton conduction behavior of the perfluorosulfonic acid membrane, a plurality of substances having an auxiliary proton conduction function are added to the perfluorosulfonic acid exchange membrane. The selected auxiliary proton conductive material particles must have the following characteristics: (1) The particles have better water retention capacity, that is, have higher water loss temperature; (2) have better compatibility with proton exchange resins; (3) Particles have certain ability to conduct protons; (4) easy to obtain nano-sized particles; (5) good structural stability of particles, no obvious structural changes during absorption and dehydration; (6) favorable for maintaining or improving proton exchange membrane Mechanical strength or physical dimensional stability. The inorganic water-retaining particles usually used are Si0 ₂ , Ti0 ₂ , Zr(HP0 ₄ ) ₂ or Zr0 ₂ particles, heteropoly acid or solid acid particles, zeolite group mineral particles, smectite and other layered clay minerals and intercalation layers thereof. Clay minerals, etc. For example, CN 1862857 discloses that the addition of an auxiliary proton conductive material such as SiO 2 to a perfluorosulfonic acid resin can improve the high temperature conductivity of the proton exchange membrane. J. Electrochem. Soc. (V154, 2007, P B288-B295) describes a composite film of Nafion resin and zirconium phosphate which still has a high electrical conductivity at a relative humidity of less than 13%.

The disadvantage is that simply adding the above substances often degrades the mechanical properties of the film and does not meet the needs of actual operation and installation. The addition of an auxiliary proton conducting material tends to cause the film to become brittle and easily broken, and the mechanical properties are greatly reduced. Summary of the invention

Proton exchange membranes for fuel cells need to meet the following requirements: Stable, high electrical conductivity, and high mechanical strength. In general, when the ion exchange capacity is increased, the equivalent value of the perfluoropolymer decreases (when the amount of EW decreases, the ion exchange capacity IEC = 1000/EW) and the strength of the membrane also decreases. The gas permeability of the membrane also increases, which can have a very serious effect on the fuel cell. Therefore, the preparation of a membrane having high ion exchange capacity while having good mechanical strength and airtightness, as well as good stability, is the key to fuel cells, especially for fuels used in vehicles such as automobiles.

Therefore, the object of the present invention is to overcome the shortcomings of the prior art proton exchange membranes which have low mechanical strength, poor chemical stability and poor air tightness, and provide a good mechanical strength, chemical stability and gas while having high ion exchange capacity. A dense proton exchange membrane and a preparation method and application of the membrane.

The invention provides a proton exchange membrane comprising 2-40 layers of a single layer membrane based on a perfluoro ion exchange resin, wherein at least one single layer membrane has a crosslinked network structure, and at least one single layer membrane comprises a surface-modified auxiliary proton conductive material, at least one single layer film containing a high-valent metal compound, to a content of the surface-modified auxiliary proton conductive material based on 100 parts by weight of the perfluoro ion exchange resin 0.05 to 50 parts by weight, preferably 1 to 15 parts by weight; the high-valent metal compound may be included in an amount of 0.0001 to 5 parts by weight, preferably 0.001 to 1 part by weight.

Wherein, the intersection network structure may be one or more of the structures shown by the formulas (1), (11), (111), (IV) and (V):

Wherein G^PG ₂ is CF ₂ or O, respectively, and R _f is a C ₂ -C _{1 ()} perfluorocarbon chain or a chlorine-containing perfluorocarbon chain;

Wherein R is a methylene group or a perfluoromethylene group, and n is an integer from 0 to 10;

According to the present invention, there is provided a proton exchange membrane, wherein the auxiliary proton conductive material is selected from the group consisting of: an oxide, an orthophosphate, a polycondensation phosphate, a polyacid, a polyacid salt and a hydrate thereof, a silicate, a sulfate, a sub One or more of selenate and arsenide; preferably one or more of oxide, orthophosphate, polyphosphate, polyacid and polyacid salt, further preferably oxide, orthophosphate Polycondensed phosphoric acid One or more of the salts.

Hereinafter, the above various auxiliary proton conductive substances will be described in detail, but the purpose is not to limit the scope of the present invention:

(1) Oxide, as shown by the formula: QO _e/2 , e=l-8; wherein Q may be a second, third, fourth, or fifth main group element or a transition element, for example: Si0 ₂ , A1 ₂ 0 ₃ , Sb ₂ 0 ₅ , Sn0 ₂ , Zr0 ₂ , Ti0 ₂ ,

Mo0 ₃ and Os0 ₄ ;

(2) Phosphate, including various forms of orthophosphates and polyphosphates of the first, second, third, fourth, fifth main group elements and transition elements. For example: BP0 ₄ , Zr ₃ (P0 ₄ ) ₄ , Zr(HP0 ₄ ) ₂ , HZr ₂ (P0 ₄ ) ₃ , Ce(HP0 ₄ ) ₂ , Ti(HP0 ₄ ) ₂ , KH ₂ P0 ₄ , Na3⁄4P0 ₄ , Li3⁄4P0 ₄ , NH ₄ H ₂ P0 ₄ , Cs3⁄4P0 ₄ , CaHP0 ₄ , MgHP0 ₄ , HSbP ₂ 0 ₈ , HSb ₃ P ₂ 0 ₁₄ , H ₅ Sb ₅ P ₂ O ₂₀ , Zr ₅ (P ₃ O ₁₀ ) ₄ and Zr ₂ H(P ₃ O ₁₀ ) ₂ ;

(3) polyacids, polyacid salts and their hydrates, as shown by the formula: AiBjCkC .mHsO, wherein A can be a first, second, third, fourth, fifth main group element, a transition element or one or two, Three, four, and five-valent groups; B and C can each independently be the second, third, fourth, fifth, sixth, and seven main group elements, transition elements; i = l-10, j = 0-50, k = 0-50, 1=2-100, m=0-50, for example: H ₃ PW ₁₂ 0 ₄ . 'aH ₂ 0 (α=21-29 ), H ₃ SiW ₁₂ O ₄₀ H ₂ O (β=21-29 ), H _x W0 ₃ , HSbW0 ₆ , H ₃ PMo ₁₂ O ₄₀ , H ₂ Sb ₄ O _u , HTaW0 ₆ , HNb0 ₃ , HTiNb0 ₅ , HTiTa0 ₅ , HSbTe0 ₆ , 3⁄4Ti ₄ 0 ₉ , HSb0 ₃ and H ₂ Mo0 ₄ ;

(4) Silicates, including zeolites, zeolites (NH ₄ ⁺ ), layered silicates, reticulated silicates, H-naite, H-mordenite, NH ₄ -antamenite, NH ₄ -alumina Stone, NH ₄ - gallate and H-montmorillonite;

(5) Sulfate, as shown by the formula: D. H _p SqO _r , wherein D may be a first, second, third, fourth, fifth main group element, a transition element or a one, two, three, four, five valent group; o=l-10, p=0- 10, q=l-5, r=2-50, for example: CsHS0 ₄ , Fe(S0 ₄ ) ₂ , (NH ₄ ) ₃ H(S0 ₄ ) ₂ , LiHS0 ₄ , NaHS0 ₄ , KHS0 ₄ , RbS0 ₄ , LiN ₂ 3⁄4S0 ₄ and NH4HSO4;

(6) Selenite and arsenide, as shown by the formula: E _s H _t F _u O _v , where A may be the first, second, third, fourth, fifth main group element, transition element or one or two , three, four, five-valent groups; F can be As or Se; s = l-10, t = 0-10, u = l-5, v = 2-50, for example: (NH ₄ ) ₃ H ( Se0 ₄ ) ₂ , (NH ₄ ) ₃ H(Se0 ₄ ) ₂ , KH ₂ As0 ₄ , Cs ₃ H(Se0 ₄ ) ₂ and Rb ₃ H(Se0 ₄ ) ₂ .

In summary, a particularly preferred auxiliary proton conducting material of the present invention may include SiO ₂ , Zr0 ₂ , Ti0 ₂ , BP0 ₄ , Zr ₃ (P0 ₄ ) ₄ , Zr(HP0 ₄ ) ₂ , H ₃ PW ₁₂ 0 ₄ . , CsHS0 ₄ , Cs3⁄4P0 ₄ , H-mordenite, H-montmorillonite, HZr ₂ (P0 ₄ ) ₃ , Zr ₃ (P0 ₄ ) ₄ , Ce(HP0 ₄ ) ₂ , Ti(HP0 ₄ ) ₂ and/or One or more of Zr ₂ H(P ₃ O ₁₀ ) ₂ . The auxiliary proton conductive material may have a particle diameter of 0.001 to 5 μm, preferably 0.01 to 1 μm. The surface of these materials may be modified with a group having an ion exchange function and/or an acidic group by a method such as cogelation, coprecipitation or hydrothermal pyrolysis. For example, in some embodiments of the invention, the specific preparation method may be: methyl or methyl sulfate and ethyl silicate or oxychloride Zirconium or titanate or the like is gelled under alkaline conditions to obtain a surface-modified auxiliary proton conductive substance.

A proton exchange membrane according to the present invention, wherein the high-valent metal compound may be a nitrate, a sulfate, or a carbon of a highest valence state and a middle valence state of W, Ir, Y, Mn, Ru, V, Ζ, and La elements. Acidate, phosphate, acetate and combined double salt, the highest and intermediate valences of W, Ir, Y, Mn, Ru, V, Ζ and La elements, cyclodextrin, crown ether, acetylacetone, Nitrogen crown ether and nitrogen-containing heterocycle, ethylenediaminetetraacetic acid, dimethylformamide and dimethyl sulfoxide complex, and the highest valence of W, Ir, Y, Mn, Ru, V, Ζ and La elements One or more of the oxides having a perovskite structure in the state and the intermediate valence state. Wherein, the oxides having a perovskite structure of the highest and intermediate valence states of the W, Ir, Y, Mn, Ru, V, Ζ, and La elements include, but are not limited to, the following compounds: Ce _x Ti _{(1- x)} 0 ₂ (x = 0.25-0.4), Ca. ₆ La. ₂₇ Ti0 ₃ , La ₍ i _-y) Ce _y Mn0 ₃ (y = 0.1-0.4) , La ₀ . ₇ Ce ₀₁₅ Ca ₀₁₅ MnO ₃ .

A proton exchange membrane according to the present invention, wherein the modified microporous membrane is selected from the group consisting of having ions

The monomer-modified organic polymer microporous membrane is particularly preferably a fluorocarbon polymer membrane. This hair

The pore diameter of 1 Mo may be O.l-ΙΟμηι, preferably 0.2-3μηι, and the thickness may be

5-100 μηι, preferably 5-30 μηι, may have a porosity of 30-99%, preferably 70-97%.

The monomer having ion exchange function may be sulfur dioxide, sulfur trioxide, and perfluorosulfonic acid monomer (Α), perfluorosulfonic acid monomer (Β), and perfluorosulfonic acid monomer (C) having the following structure: One or more of them:

CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ SO ₂ A

CF (A)

Where h = 0-l, i= 1-5, A is F, Cl, Br, OH, i methyl (OCH ₃ ) or ONa; j = 0-1, k = 1-5, B is methyl (Me), H or ethyl (Et); 1 = 1-5, D is H, methyl (Me) or ethyl (Et).

A proton exchange membrane according to the present invention, wherein the proton exchange membrane preferably comprises 2-20 layers, more preferably 2-5 layers of a monolayer film based on a perfluoro ion exchange resin. The proton exchange membrane may have a thickness of 10 to 300 μm, preferably 10 to 150 μm, more preferably 10 to 50 μm. According to the proton exchange membrane provided by the present invention, each layer may be exchanged by a perfluorinated ion; the lipid formation may also be formed by mixing a plurality of perfluoro ion exchange resins, and each layer may be formed into a crosslink or a partial layer may not be formed. Crosslinked structure. In the proton exchange membrane of the present invention, the perfluoro ion exchange resin may be crosslinked on the surface of the microporous membrane or may be crosslinked in the void of the microporous membrane. Since the porous film is subjected to surface activation modification, having an acidic or functional group allows a strong crosslinking effect between the porous film and the film-forming resin by physical bonding of the high-valent metal compound.

The perfluoro ion exchange resin is formed by copolymerization of a perfluoroolefin monomer, one or more functional group-containing perfluoroolefin monomers, and one or more perfluoroolefin monomers having a crosslinking site. Or a mixture of the above copolymers having an EW value of from 600 to 1300, preferably from 700 to 1200.

Wherein the perfluoroolefin monomer is selected from one or more of tetrafluoroethylene, chlorotrifluoroethylene, trifluoroethylene, hexafluoropropylene and vinylidene fluoride, preferably, the perfluoroolefin monomer The functional group-containing perfluoroolefin monomer which is tetrafluoroethylene is selected from one or more of the structures of the formulae (VII), (VIII) and (IX):

Y _l (C¥ ₂ C¥R _n ) _h (C¥R _f2 ) _c O(CFCF ₂ O) ■CF=CF,

CF _? X ( VII )

CF(CF ₂ ) _d Y ₂ ( VIII )

CF〇CF ₂ CFOCF ₂ CF ₂ Y:

CF ₂ 〇CF ₃ ( IX ) wherein a, b, c are each independently 0 or 1, but are not simultaneously zero; d is 0-5 white n is 0 or 1; R _fl , Rf ₂ and respectively selected from Perfluorodecyl and fluorochloroindolyl; X is selected from the group consisting of F, Cl, Br and I; Y, Υ ₂ and Υ ₃ are each independently selected from the group consisting of S0 ₂ M, COOR ₃ and PO(OR ₄ )(OR ₅ ), Wherein: M is selected from the group consisting of F, Cl, OR, and NRiR ₂ ; R is selected from the group consisting of methyl, ethyl, propyl, H, Na, Li, K, and ammonium; and is selected from the group consisting of 11, methyl, ethyl, and ethyl, respectively. R _{3 is} selected from the group consisting of H, Na, Li, K, ammonium, methyl, ethyl and propyl; and R ₄ and R ₅ are each selected from the group consisting of 11, Na, Li, K and ammonium.

The perfluoroolefin monomer having a crosslinking site is selected from one or more of the structures represented by the following formulas (Χ) and (XI):

F ₂ C ^= CF Rf ₄ Y4

(X)

Wherein Y ₄ and Y ₅ may be selected from Cl, Br, I and CN, respectively; a, b, and c are 0 or 1, respectively, but a, +b, +c, ≠0; selected from F, Cl , Br and I; n, are 0 or 1; R _f4 , R _f5 and R _f6 are each independently selected from perfluorodecyl.

The invention also provides a preparation method of the above proton exchange membrane, the method comprising:

(1) forming a monolayer film using a solution or a melt containing a perfluoro ion exchange resin, wherein the solution or melt selectively contains one of a surface-modified auxiliary proton conductive substance, a modified fiber, and a high-valent metal compound Species or more;

(2) forming a cross-linked network structure in the monolayer film obtained in the step (1);

(3) at least one step (2) is obtained by combining a single layer film with at least one layer of the modified microporous film, while selectively combining the single layer film obtained in the steps (1) and/or (2), and / or selectively using the solution or melt described in step (1) to form a monolayer film therein, the resulting composite film comprising 2-40 single layer films, wherein at least one single layer film contains surface modification Auxiliary proton conducting material, at least one single layer film containing modified fibers, at least one single layer film

Wherein the intersection network structure is one or more of the structures represented by the formulas (1), (11), (111), and (IV (V):

(I)

, G^PG ₂ is a perfluorocarbon chain or a chlorine-containing perfluorocarbon chain of CF ₂ or O, R _f -C ₁₍₎

(II) (in) wherein R is methylene or perfluoromethylene and n is 0-10

According to the method provided by the present invention, steps (1) and (2) may be performed simultaneously, or step (1) may be performed first and then step (2).

Wherein, the method of forming the single layer film in the step (1) is one or more of casting, melt extrusion, hot pressing, spin coating, casting, screen printing, spraying, and dipping.

Preferably, the method of casting, casting, screen printing, spin coating, spraying or dipping is as follows:

(a) dispersing a perfluoro ion exchange resin, a fiber as a reinforcement, an auxiliary proton conductive substance, a crosslinking agent, an acid or a radical initiator, and a high-valent metal compound into a solvent to form a mixture; The solid content of the perfluoro ion exchange resin in the mixture may be from 1 to 80% by weight, and the solvent used may be dimethylformamide, dimethylacetamide, methylformamide, dimethyl sulfoxide, N-methyl One or more of pyrrolidone, hexamethylphosphoric acid, acetone, water, ethanol, methanol, propanol, isopropanol, ethylene glycol, and glycerol;

(b) forming a film by solution casting, solution casting, screen printing, spin coating, spraying or dipping on the plate or the prepared single layer or multilayer film by using the solution prepared in the step (a); Heat treatment at a temperature of 30-250 ° C for 0.01-600 minutes, preferably at 100-200 ° C for 1-30 minutes;

It may be crosslinked in film formation or after film formation, as shown by the formulas (1), (11), (111), (IV) and (V):

Wherein G^PG ₂ is CF ₂ or O, respectively, and R _f is C . Perfluorocarbon chain or chlorine-containing perfluorocarbon chain;

Wherein R is methylene or perfluoromethylene, and n is 0-10

Wherein the method of forming the crosslinked structure represented by the formula (I) includes heat, light, electron radiation, plasma, X-ray, or a radical initiator, and may also pass heat in the presence of one or more crosslinking agents. , light, electron radiation, plasma, X-ray,

Structure. The structure of the crosslinking agent used therein is as shown in the following formula (VI).

^X 2 ^R f7 ^X 3 ( VI ) wherein X ₂ and X ₃ are each independently CI, Br or I; 3⁄47 is a perfluorodecyl or fluorochloroindenyl group; preferably, the radical initiator is organic a peroxide or an azo-based initiator; preferably, the initiator is an organic oxide initiator; more preferably, the initiator is a perfluoroorganic peroxide.

The method for forming the (11) and (III) crosslinked structures is: using a sulfonyl fluoride, a sulfonyl chloride, a sulfonyl bromide type resin with ammonia, hydrazine, an organic diamine or capable of chemically releasing ammonia, hydrazine, and an organic diamine. The material reaction is obtained.

The organic diamine is a C1-C10 decyl diamine or a perfluorodecyl diamine, and the substances capable of chemically releasing ammonia, hydrazine, and organic diamine include, but are not limited to, ammonia, hydrazine, organic An organic or inorganic acid salt of a diamine, urea, or hydrazine.

The method of forming the (IV) crosslinked structure is obtained by treating a perfluorosulfonic acid resin with chlorosulfonic acid.

The method for forming the (V) crosslinked structure is a perfluorosulfonic acid resin containing a nitrile group or a perfluorosulfonyl fluoride resin containing a nitrile group, a sulfonyl chloride resin, a sulfonyl bromide resin in heat or acid Formed under the action.

The acid is a strong protic acid or a Lewis acid; wherein the protonic acid is selected from the group consisting of 3⁄4S0 ₄ , CF ₃ S0 ₃ H And: _3⁄4 ?0 ₄ ; Lewis acid is selected from the group consisting of ZnCl ₂ , FeCl ₃ , A1C1 ₃ , organotin, organic germanium and organic germanium. Preferably, the method of melt extrusion and hot pressing is as follows:

(a) Preparing suitable sulfonyl fluoride, sulfonyl chloride, sulfonyl bromide resin, modified fiber, surface-modified auxiliary proton conductive material, crosslinking agent according to the requirements of each layer of the multi-layer cross-linked perfluorinated ion exchange membrane. a mixture of one or more of an acid or a free radical initiator and a high-valent metal compound, using a twin-screw extruder, an internal mixer or an open mill at 200-28 (TC mixing;

(b) The resin mixed in the step (a) is formed into a film by a screw extruder or a flat vulcanizer; the method may also be crosslinked in a film formation or after film formation to obtain a crosslinked single layer film as described above. According to the method provided by the present invention, the method of compounding in the step (3) may be a single layer film composite, a multilayer film and a single layer film composite, a multilayer film and a multilayer film composite, and a solution or a melt in a single film. One or more of the methods of directly forming a single layer film on a film or a multilayer film. That is to say, each single layer film can be formed by casting, extrusion, hot pressing, spin coating, casting, screen printing process, spraying or dipping process of solution or melt; multilayer film is prepared by single layer Inter-membrane recombination, composite between multilayer film and single-layer film, or composite film between multi-layer film and multi-layer film, can also directly use casting or extruding of solution or melt on the obtained single-layer film or multi-layer film. Prepared by hot pressing, spin coating, casting, screen printing, spraying or dipping.

Preferably, the obtained monolayer film may be first converted into an acid form prior to recombination, or may be first combined with other films and then converted into an acid form.

It is also possible to extrude the resin to form a monolayer film, hydrolyze it into a hydrogen type film, and then soak the film in a solution of a high-valent metal compound to achieve physical bonding crosslinking.

Preferably, the crosslinking described in the step (2) means crosslinking using various crosslinking means as described above. The method according to the present invention, wherein the surface-modified auxiliary proton conductive substance is an auxiliary proton conductive substance modified by a group having an ion exchange function and/or an acidic group; the auxiliary proton conductive substance is selected from the group consisting of: oxidation One or more of substances, orthophosphates, polycondensation phosphates, polyacids, polyacid salts and hydrates thereof, silicates, sulfates, selenites and arsenides; preferably oxides, orthophosphoric acid One or more of a salt, a polycondensation phosphate, a polyacid, and a polyacid salt is further preferably one or more of an oxide, an orthophosphate, and a polyphosphate. Specific examples of various auxiliary proton conductive substances are as described above. The surface of these materials may be modified with a group having an ion exchange function and/or an acidic group by a method such as cogelation, coprecipitation or hydrothermal pyrolysis. For example, in some embodiments of the present invention, the specific preparation method may be: gelating methyl phosphate or methyl sulfate and ethyl silicate or zirconyl chloride or titanate under alkaline conditions to obtain a surface Modified auxiliary proton conducting material. The high-valent metal compound can form a physical bond crosslink with the acidic exchange group in the film. This cross-linking mode has a large degree of cross-linking and does not affect the electrical conductivity of the film. A proton exchange membrane according to the present invention, wherein the high-valent metal compound may be w,

The highest and intermediate valence states of the Ir, Y, Mn, Ru, V, Ζ, and La elements of nitrates, sulfates, carbonates, phosphates, acetates, and complex double salts, W, Ir, Y, The highest valence and intermediate valence of Mn, Ru, V, Ζ, and La elements of cyclodextrin, crown ether, acetylacetone, nitrogen-containing crown ether, and nitrogen-containing heterocycle, ethylenediaminetetraacetic acid, dimethylformamide And dimethyl sulfoxide complex, and one or more of the highest valence state and the intermediate valence state of the W, Ir, Y, Mn, Ru, V, Ζ, and La elements having a perovskite structure Kind. Wherein, the oxides having a perovskite structure of the highest and intermediate valence states of the W, Ir, Y, Mn, Ru, V, Ζ, and La elements include, but are not limited to, the following compounds: Ce _x Ti _{(1- x)} 0 ₂ (x = 0.25-0.4), Ca. ₆ Lao. ₂₇ Ti0 ₃ , La ₍ i _-y) Ce _y Mn0 ₃ (y = 0.1-0.4) , La ₀ . ₇ Ce ₀₁₅ Ca ₀₁₅ MnO ₃ .

The method according to the present invention, wherein the modified microporous membrane is selected from the group consisting of an organic polymer microporous membrane modified with a monomer having an ion exchange function, particularly preferably a fluorocarbon polymer membrane having a pore diameter of Ol- ΙΟμηι, preferably 0.2-3μηι; thickness 5-100μηι, preferably 5-30μηι; porosity 30-99%, preferably 70-97%; the ion exchange function monomer is sulfur dioxide, sulfur trioxide And one or more of a perfluorosulfonic acid monomer (Α), a perfluorosulfonic acid monomer (Β), and a perfluorosulfonic acid monomer (C) having the following structure:

Wherein, h = 0-l, i = 1-5, VIII, Cl, Br, OH, methyl (OCH ₃ ) or ONa; j = 0-1, k = 1-5, B is methyl ( Me), H or ethyl (Et); 1 = 1-5, D is H, methyl (Me) or ethyl (Et).

The microporous membrane as a reinforcement is subjected to surface activation modification by a 4p mass having an ion exchange function, and the specific modification method may be: heating the microporous membrane and the monomer having ion exchange function in heat, light, and electron radiation. The reaction occurs under the action of a plasma, an X-ray, a radical initiator or the like, and then the modified microporous membrane generates an ion exchange group under the action of an acid or a base.

The microporous membrane used is preferably subjected to surface silicic acid, sulfonation, sulfation, phosphorylation, and hydrophilization. Sex. Specific modification methods can be referred to the prior art. The present invention provides the following microporous membrane surface modification method: For example, for the fluorocarbon polymer membrane, the surface is subjected to silicic acid, sulfonation, sulfation, phosphorylation and the like. Existing surface modification methods for polytetrafluoroethylene are suitable for modification of fluorocarbon polymer membranes, including reduction modification of naphthalene solution, laser radiation modification, plasma modification, and silicic acid activation. Among them, the silicic acid activation method is the preferred method because it can directly deposit water-retaining silica on the surface of the fluorocarbon polymer film. By modifying the surface of the fluorocarbon polymer film to have a hydrophilic group, but it is preferable to further modify the modified fiber such as ethyl orthosilicate, ZrOCl ₂ - 3⁄4P0 ₄ or titanium. Further modification in acid esters and the like. For example, a specific method of the silica-modified porous polytetrafluoroethylene film is to place the porous polytetrafluoroethylene film in an atmosphere of SiCl ₄ for 1 hour, then raise the temperature to 110 ° C for 1 hour, and then cool to 60 ° C. , water spray treatment to obtain a silica modified porous polytetrafluoroethylene film.

The fluorine-containing ion exchange resin in the microporous membrane-reinforced multilayer fluorine-containing crosslinked doped ion membrane of the present invention may be crosslinked on the surface of the microporous membrane or may be crosslinked in the void of the microporous membrane. Since the porous film is subjected to surface activation modification, it has an acidic or functional group to form a strong crosslinking effect between the porous film and the film-forming resin by physical bonding of the high-valent metal compound.

The proton exchange membrane according to the present invention, wherein the proton exchange membrane preferably comprises 2 to 20 layers, more preferably 2 to 5 layers of a monolayer film based on a perfluoro ion exchange resin. The proton exchange membrane may have a thickness of from 5 to 300 μm, preferably from 10 to 50 μm. Here, each layer may be formed of a perfluoro ion exchange resin or a mixture of a plurality of perfluoro ion exchange resins, and each layer may form a crosslinked structure or a partial layer may not form a crosslinked structure.

A proton exchange membrane according to the present invention, wherein the perfluoro ion exchange resin is a perfluoroolefin, one or more functional group-containing perfluoroolefin monomers, and one or more crosslinking sites The copolymer of perfluoroolefin monomers or a mixture of the above copolymers may have a ring number of from 600 to 1300, preferably from 700 to 1200.

Wherein, the perfluoroolefin is selected from one or more of tetrafluoroethylene, chlorotrifluoroethylene, trifluoroethylene, hexafluoropropylene and vinylidene fluoride. Preferably, the perfluoroolefin is tetrafluoroethylene. and / or ^f trifluoroacetic containing one or more perfluoroalkylene group selected from the functional monomer of formula (VII), (VIII) and (IX) shown in the structure:

( VII ) Rf3 ^C F=CF(CF ₂ ) _d Y ₂ ( _vm )

Wherein, a, b, c are each independently 0 or 1, but are not simultaneously zero; d is 0-5 white n is 0 or 1; R _fl , Re and Re are respectively selected from perfluorodecyl and fluorochloroguanidine X is selected from the group consisting of F, Cl, Br and I; Yj, Y ₂ and Y ₃ are each independently selected from the group consisting of S0 ₂ M, COOR ₃ and PO(OR ₄ )(OR ₅ ), wherein: M is selected from F, Cl , OR, nRiR _2; R is selected from methyl, ethyl, propyl, H, Na, Li, K and ammonium; R PR ₂ 11 are independently selected from methyl, ethyl and propyl; R ₃ is selected from H, Na, Li, K, ammonium, methyl, ethyl and propyl; R ₄ and R ₅ are each selected from the group consisting of 11, Na, Li, K and ammonium.

Y ₅ (CF ₂ ) _a , (CFR _f5 ) _b , (

Wherein, Υ ₄ and Υ ₅ may be respectively selected from Cl, Br, I and CN; a, b, and c are 0 or 1, respectively, but a, +b, +c, ≠0; selected from F, Cl , Br and I; n, are 0 or 1; R _f4 , R _f5 and R _f6 are each independently selected from perfluorodecyl.

In a preferred embodiment of the present invention, the method for preparing a proton exchange membrane of the present invention may comprise the following steps:

(1) using a solution or melt containing a perfluoro ion exchange resin, an auxiliary proton conductive substance, or a high-valent metal compound by casting, extrusion, hot pressing, spin coating, casting, screen printing process, spraying or dipping process a plurality of single-layer films may also be combined with a modified microporous film to form a film;

(2) The preparation of the multilayer film may be carried out by a single layer film composite prepared in (1), or the solution or melt described in (1) may be used on the basis of a single layer film or a multi-layer film. The material is produced by casting, extrusion, hot pressing, spin coating, casting, screen printing, spraying or dipping, and can also be formed by laminating a multilayer film with a single layer or a multilayer film and a multilayer film. When compounding, ensure that the composite film is

(3) When it is necessary to add a crosslinking agent and/or an initiator, the crosslinking agent and/or the initiator may be added during the step (1) and/or (2), or may be a crosslinking agent and/or an initiator. Dispersing in a solvent and entering the film by swelling the film in a solvent;

(4) The membranes treated in the steps (2) and (3) are treated under the action of the aforementioned method to form (5) sequentially obtaining a microporous membrane-reinforced crosslinked perfluoro ion exchange membrane by treatment with an alkali solution or an acid solution, wherein the acid is preferably hydrochloric acid, sulfuric acid or nitric acid; the base is preferably LiOH, NaOH or KOH; Both the lye and the acid are aqueous solutions.

The present invention also provides the use of the proton exchange membrane of the present invention or the proton exchange membrane prepared according to the preparation method provided by the present invention in a proton exchange membrane fuel cell.

In the present invention, the microporous membrane composite multi-layer perfluorocrosslinked doped ion membrane uses a microporous membrane, chemical bonding cross-linking, and physical bonding and crosslinking of a high-valent metal compound with an acidic exchange group, and the like. The mechanical strength of the ion membrane is increased. In particular, the physical bonding between the high-valent metal compound and the acidic exchange group has a high degree of crosslinking and can achieve cross-linking between the layers, together with an amide group in the chemical bonding of the amide. The triazine group in the triazine ring-bonding crosslink can also form a coordination with the high-valent metal compound, which further improves the performance of the film. In particular, it is emphasized that a microporous membrane whose surface is modified by an acidic exchange group can form a physical bond crosslink by physical bonding with a high-valent metal compound and a film-forming resin. This solves the problem that the conventional microporous membrane-enhanced perfluorosulfonic acid membrane enhances the gas permeability of the perfluorosulfonic acid membrane. The possible reasons are as follows: 1. The surface functionalized microporous membrane has improved adhesion to the film-forming resin; 2. Since the surface of the microporous membrane has functional groups, it can form a bonding structure with the metal compound, further reducing the resin. And the gap between the fibers. In the past, the membrane with the auxiliary proton-conducting substance was added, although the high-temperature proton conductivity was improved, but the mechanical properties were significantly reduced. In our invention, due to the above cross-linking modification, and at the same time, since some of the surface of the auxiliary proton-conducting substance is modified by a reactive group, a physical cross-linking structure can be formed with the high-valent metal compound. This ensures that they not only contribute to the proton conduction of the membrane, but also contribute to the mechanical properties of the membrane. Therefore, the proton exchange membrane provided by the present invention has good mechanical strength, high temperature conductivity and airtightness while having high ion exchange capacity. The best way to implement the invention

The present invention is further described in detail with reference to the preferred embodiments thereof. Example 1

This embodiment is for explaining the proton exchange membrane provided by the present invention and a preparation method thereof.

Will repeat the unit as

The sub-exchange resin and the cerium carbonate (weight ratio to the resin: 1:100), Zr(HP0 ₄ ) ₂ having a particle size of 0.005 μη (the weight ratio to the resin is 3:100), and 5 wt% of propanol Aqueous solution. A solution of perfluoromalonyl peroxide in DMF at a concentration of 5% by weight was then prepared.

Take a thickness of 30μηι, porosity

The surface-modified polytetrafluoroethylene microporous membrane is immersed in the above solution for about 1 hour, and then the soaked film is dried on a hot plate with a glue therebetween. The roller rolls the film. The solution was cast into a horizontally placed polytetrafluoroethylene mold, and after vacuum drying at 80 ° C for 12 hours, the film was peeled off to obtain a monolayer of perfluorosulfonic acid crosslinked to the (I) type of doped ion film. (1 #膜). The above two single-layer perfluorocrosslinked doped ion membranes were stacked and hot pressed to obtain a proton exchange membrane of the present invention, which was designated as Al. Example 2

This embodiment is for explaining the proton exchange membrane provided by the present invention and a preparation method thereof ₍

Will repeat the unit as

, EW=800 perfluoro ion exchange resin and SiO ₂ with a particle size of 0.03μηι (5:100 by weight to resin), and the surface is CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ S0 ₂ A

CF ₃ (where _h=0 , i= ₄ , A=ONa ) modified perfluoroethylene propylene fibers (diameter 0.05 μm length 5 μm, weight ratio to resin 1:40) mixed extrusion to obtain a film having a thickness of 30 μm .

CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ S0 ₂ A

(wherein h=0, i=4, A=ONa) the surface-activated porous hexafluoropropylene film having a thickness of 12 μm and the above-mentioned film of 30 μm are passed at 260 ° C. The sheets were hot pressed together in an empty state, and then immersed in a DMF solution of NH ₄ C1 for 5 hours in a vacuum oven at 150 ° C for 5 hours. The soaked film was then placed in triethylamine at 200 ° C for 2 hours to obtain a crosslinked film. The crosslinked structure in which the membrane was treated with a KOH solution or a hydrochloric acid solution in this order was an ion exchange membrane (2# membrane) of the above (II).

Will repeat the unit as

CF.

EW=1200 of perfluoro ion exchange resin and tetraphenyltin were extruded into a film of 20 μm by a twin-screw extruder, and then the film was heated to 230 ° C for 10 hours to obtain a crosslinked structure of the (V) species. membrane. The film was sequentially treated with LiOH and a nitric acid solution to obtain a crosslinked ion film (3# film).

The 2# and 3# films were stacked, hot pressed, and immersed in a manganese nitrate solution for 1 hour to obtain a thickness of

The proton exchange membrane of the present invention of 50 μm is designated as Α2. Example 3

Will repeat the unit as

a perfluoro ion exchange resin, cerium acetate (weight ratio to resin: 0.001:100) and Ce(HP0 ₄ ) ₂ (weight ratio to resin: 0.001:100) are formulated into a solution having a resin content of 3% by weight (solvent) For weight

More than 1:1 water and ethanol).

(1=1, D=H) The porous polytetrafluoroethylene-hexafluoropropylene film of the technology was immersed in the above solution, and after 30 minutes, the film was taken out and dried, and then the film was crosslinked by 50 KGy radiation to obtain a thickness of ΙΟμηι. The crosslinked structure is the ion film of the (I) type (4# film).

, _£ ^ ₉₄₀ full repeat unit is fluorine ion exchange resin, Ce (III)-DMSO complex (weight ratio of resin to resin: 0.1:100) and H3PW12O40 (weight ratio of resin to resin: 20:100) A film having a resin content of 30% by weight in DMSO was obtained by casting at 170 ° C for 60 minutes to obtain a film having a thickness of ΙΟμηι (5

#membrane).

The obtained films were laminated in the order of 4 # -4 # -5 # and hot pressed to obtain a proton exchange membrane of the present invention having a thickness of 30 μm, which is designated as A3. Example 4

Will repeat the unit as

_{? EW=700} full

Sub-exchange resin,

Ce(HP0 ₄ ) ₂ (weight ratio to resin: 0.1:100), 18-crown-6 complexed ruthenium (ΠΙ) compound (weight ratio to resin: 0.03: 100) mixed in DMF to form resin 20% by weight of dissolved

(1=1, D=H) The modified porous tetrafluoroethylene-perfluoromethoxyethylene copolymer film was placed in the solution, immersed for 1 hour, and then treated at 120 ° C for 10 minutes to obtain a thickness of ΙΟμηι. Fiber reinforced monolayer perfluorosulfonic acid ion membrane. The ion exchange membrane was immersed in chlorosulfonic acid to obtain a membrane (6# membrane) having a crosslinked structure of the formula (IV).

The 6# film was placed in the DMF solution of the resin of Example 1 and 0.1% perfluoroperyl laurethoyl, 5% 1,4-diiodooctafluorobutane, and immersed for 0.5 hour, taken out and dried, and the above steps were repeated; The film was then treated at 120 ° C for 300 minutes to obtain a #7 film. The 7# film and the ## film were heat-pressed to obtain a proton exchange membrane of the present invention having a thickness of 35 μm, which was designated as Α4. Example

This embodiment is for explaining the proton exchange membrane provided by the present invention and a preparation method thereof ₍ CF ₂ CF ₂ 7CF ₂ CF— j-CF ₂ CF2†CF ₂ CF

CI OCF ₂ CFOCF ₂ CF ₂ S〇 ₃ H The repeating unit is ^CF 3 ,

EW=1300 perfluoro ion exchange resin and acetylacetone-Ce(III) complex (weight ratio of resin to 0.01:100), surface sulfuric acid modified Zr0 ₂ with particle size of 0.8μη (with resin weight) A ratio of 2:100), azobisisovaleronitrile (0.1:100), 1,4-diiodooctafluorobutane (weight ratio of 1:100 to resin) dissolved in DMF to a resin content of 10 % by weight solution.

CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ S0 ₂ A Polyvinylidene fluoride porous membrane with a surface of ^CF 3 (where h=0, i=4, A=ONa) (porosity 80 %, thickness 20 μηι) After immersing in the above solution for 30 min, it was treated at 170 ° C for 60 min to obtain a film (8# film) having a thickness of 20 μm.

The ruthenium-mordenite powder having a particle size of 5 μm (the weight ratio of the resin to the resin was 1:1) was mixed with ruthenium-methylpyrrolidone using the resin of Example 4 to prepare a solution having a resin content of 3% by weight. This solution was spin-coated on both surfaces of the 8# film to form a film having a thickness of 30 μm (multilayer film 1#). The multi-layer film 1# was treated at 69 ° C for 2.4 hours to obtain a perfluorosulfonic acid film of the formula (I) in which the metal ion-bonded three-layer crosslinked structure was obtained.

The film was again placed in the perfluoro ion exchange resin of the present example, yttrium-montmorillonite having a particle diameter of ΙΟμηι (weight ratio of 0.5:100 to resin), and azobisisovaleronitrile (weight ratio to resin) 0.5:100), 1,4-diiodooctafluorobutane (3:100 by weight to resin) and DMF-Ce(III) complex (weight ratio of 1:100 to resin) are dissolved in The solution prepared in DMF has a resin content of 25% by weight. After soaking for 0.5 hours, the film was taken out and dried. The above procedure was repeated, and then the film was treated at 120 ° C for 300 minutes to obtain a metal ion-bonded five-layer microporous film. Perfluorosulfonic acid crosslinked ion membrane (multilayer film 2#).

The multilayer films 1# and 2# were hot pressed to obtain a metal ion-bonded ten-layer microporous film-enhanced perfluorosulfonic acid cross-linked ion doped film, i.e., the proton exchange membrane of the present invention, which is designated as A5. Example 6

Will repeat the unit as

EW=1300 full ion exchange resin and

(y=0.5), the weight ratio to the resin is 0.01: 100) dispersed in hexamethylphosphoric acid amine (forming a 30% solution), and then H-montmorillonite having a particle size of 0.7 μm (with the weight of the resin) The ratio is 10:100), after mixing, by the vacuum coating method on the surface

CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ S0 ₂ A

CF ₃ (where h=0, i=2, A=OH) modified polytrifluoride: surface of pore film (porosity 80%, thickness 20 μηι), a film having a thickness of 20 μm was obtained, and the film was at 23 (TC) The mixture was treated for 100 min to obtain a monolayer perfluorosulfonic acid membrane (9# membrane) having a crosslinked structure of the formula (I).

A cross-linked perfluorosulfonic acid film having a thickness of 60 μm was prepared by spraying on both surfaces of the 9# film, and a 9# film was separately pressed on both surfaces to prepare a proton exchange membrane of the present invention. , as Α6. Example 7

Will repeat the unit as

EW=1300 perfluoro ion exchange resin and La(OH) ₃ (weight ratio to resin: 0.5:100), benzoyl peroxide (weight ratio to resin: 0.1:100), 1,14- Diiodo-decafluorodecene (5:100 by weight to resin) Dissolved in dimethyl sulfoxide (resin content of 28% by weight), and TiO2 with a particle size of 3μη (the weight ratio to the resin is : 15:100) Mix to make a solution.

CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ S0 ₂ A

- the surface is modified (where h = l, i = 2, A = OH) A polytetrafluoroethylene-ethylene microporous membrane (porosity 79%, pore diameter 5 μm, thickness 30 μηι) was immersed in the above solution and treated at 160 ° C for 3 minutes. A crosslinked 30 μηι-doped microporous membrane-enhanced perfluorosulfonic acid membrane was obtained. (10# film).

The 10# film was placed in the resin, zeolite (0.4:100 by weight ratio to the resin) and benzoyl peroxide (weight ratio to resin: 0.1:100), 1,14-diiodide Soaking in a dimethyl sulfoxide solution (resin content of 20% by weight) of decafluorodecazone (5:100 by weight of resin) for 0.5 hours, taking out the film and drying, repeating the above steps, and then placing the film at 120 ° The mixture was treated at C for 300 minutes to obtain a three-layer perfluorosulfonic acid cross-linked doped ion film (multilayer film 3#).

The three multilayer films 3# were stacked and hot pressed to obtain a reinforced nine-layer fiber-reinforced perfluorosulfonic acid cross-linked ion-exchange film, i.e., the proton exchange membrane of the present invention, designated A7. Example 8

Will repeat the unit as

+ CF ₂ CF ₂ 4 CF ₂ CF~["CF ₂ CF ₂ +CF ₂ CF -

OCF ₂ CF ₂ CF ₂ l 〇CF ₂ CF〇CF ₂ CF ₂ CF ₂ S〇 ₃ H

CF ₃ , EW=1250 perfluoro ion exchange resin, pyridine-Ru complex solution (weight ratio of resin to 0.63:100) and CsH ₂ P0 ₄ (weight ratio of resin to resin: 20:100), then Dissolved in hexamethylphosphoric acid to obtain a solution having a resin content of 30% by weight.

0 The surface with a thickness of ΙΟμηι and a porosity of 89% is ⁰ ^ ⁰ ^ ^ ² ) ¹ ^^ ( 1 = 1 ,

D = H) A modified porous tetrafluoroethylene-perfluoromethoxyethylene copolymer film (having a porosity of 79 % and a pore diameter of 5 μm) was immersed in the above solution for about 1 hour to obtain a film having a thickness of ΙΟμηι. The film was treated at 230 ° C for 100 min to obtain a crosslinked single-layer microporous enhanced doped perfluorosulfonic acid film (11# film).

A crosslinked three-layer doped perfluorosulfonic acid film of 60 μm was prepared by spraying on both surfaces of the 11# film using a solution forming the 11# film. The 11# film was heat-pressed on both surfaces of the three-layer film to obtain a crosslinked five-layer microporous film-enhanced doped perfluorosulfonic acid film, that is, the proton exchange membrane of the present invention, which was designated as Α8. Example 9 This embodiment is for explaining the proton exchange membrane provided by the present invention and a preparation method thereof.

CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ S0 ₂ A Take a thickness of 30μηι, and the surface with a porosity of 50% is CF ₃

(h=0, i=2, A=OH) modified expanded polytetrafluoroethylene microporous membrane and repeat unit

EW=900 resin and particle size of 0.03μηι

Si0 ₂ (weight ratio to resin: 5:100) was hot pressed into a film. The membrane was immersed in a DMF solution of NH ₃ (concentration of 10%) for 5 hours. A film of the (II) crosslinked structure was obtained at 200 °C. The membrane was treated with an alkali solution and an acid solution, and then immersed in a DMF solution of acetylacetone-Ir(III) (concentration: 0.8%) to obtain a metal ion-bonded crosslinked membrane (12# membrane).

Will repeat the unit structure as

CF.

The resin of EW=1200 and tetraphenyltin were mixed by a twin-screw extruder. Then with a thickness of 50μηι, hole

CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ S0 ₂ A The polytetrafluoroethylene microporous membrane modified by i=4, A=OH) with a porosity of 80% (porosity 85%, The pore size of 1 μm was hot-pressed, and then the film was heated to 230 ° C for 10 hours to obtain a film of the (V) crosslinked structure. The film was placed in 35% hydrazine hydrate for 10 hours, and after heating for 5 hours, a film having the (V) crosslinked structure and the (III) crosslinked structure was obtained, and the film was made with an alkali solution, acid. After the liquid treatment, the film was immersed in cerium nitrate for 2 hours to obtain a cerium ion-bonded doped crosslinked film (13# film).

According to the film A8 of the single layer film 12#-monolayer film 13#-the film A8 of the embodiment 8 and the film A5 of the embodiment 5, the crosslinked microporous film having a thickness of 300 μm is laminated to obtain a sixteen layer film, that is, the present invention. The proton exchange membrane of the invention is referred to as Α9. Example 10 This embodiment is for explaining the proton exchange membrane provided by the present invention and a preparation method thereof ₍

The total of EW=1300; the sub-exchange resin (the weight ratio of the two is 1:0.2) and the nitrogen-containing crown ether-Ce complex (the ratio of the total weight to the resin is 1:100), the phosphoric acid modified particle size Mixing 10 nm of Zr0 ₂ (the ratio of the total weight of the resin to 2:100) and azobisisovaleronitrile (the ratio of the total weight of the resin to 5:100), dissolved in DMF to make the total resin content 20% by weight solution.

0 A microporous polytetrafluoroethylene-hexafluoropropylene film (porosity) modified by ^{CT2=CT( a3⁄41} ^0D (1=3, D=H ) for surface phosphorylation with a thickness of 50 μm and a porosity of 75%. 80%, pore size 0.5 μm) was immersed in the above solution for about 3 hours, and heated at 140 ° C to obtain a perfluorosulfonic acid membrane containing the (I) crosslinked structure having a thickness of 50 μm, and then the membrane was placed in chlorosulfonate. A film (14# film) containing both the (I) and (IV) crosslinked structures was obtained in the acid.

The film #2 was heat-pressed with the film Α2 obtained in Example 2 to obtain a metal ion-bonded perfluorosulfonic acid microporous film-reinforced crosslinked ion film, i.e., the proton exchange membrane of the present invention, which was designated as Α10. Example 11

Will repeat the unit as

, EW=1200 perfluoro ion exchange resin, Mn(OH) ₃ (weight ratio to resin: 2:100) and triphenyltin hydroxide (0.5:100 by weight to resin) and particle size 8μηι Zr0 ₂ (weight ratio to resin: 2:100) was dispersed in DMF to form a solution having a resin content of 25% by weight.

CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ S0 ₂ A Take CF _{3 with a} thickness of 20 μm and a porosity of 65%.

(h=0, i=2, A=OH) The surface sulfation-modified porous polytetrafluoroethylene microporous membrane (porosity 92%, pore size 0.5 μm) was immersed in the above solution for about half an hour at 170 The film having the (V) crosslinked structure (15# film) having a thickness of 20 μm was obtained by treating at 60 °C for 60 min.

The resin in Example 4 and the cerium-mordenite powder having a particle diameter of 5 μm (the weight ratio to the resin was 1:1) were mixed in Ν-methylpyrrolidone to form a solution having a resin content of 15% by weight.

The perfluorosulfonic acid resin and the 5 μηι- mordenite powder (the mass ratio of the lanthanum-mordenite and the resin were 1:1) mixed in Example 4 were mixed with Ν-methylpyrrolidone on both sides of the above film. A 30 μηι film was prepared to obtain a three-layer microporous enhanced perfluoro ion exchange membrane. The film was treated at 190 ° C for 2.4 h. A three-layer crosslinked microporous membrane-enhanced perfluorosulfonic acid membrane (multilayer film 14#) obtained by manganese ion bonding was obtained. A film having a thickness of 30 μm was spin-coated on both surfaces of the 15# film to obtain a three-layer microporous reinforced perfluoro ion exchange membrane. The film was treated at 190 ° C for 2.4 hours to obtain a manganese ion-bonded three-layer crosslinked microporous membrane-enhanced perfluorosulfonic acid membrane, i.e., the proton exchange membrane of the present invention, designated as All. Example 12

Will repeat the unit as

EW=1200 Perfluoro ion exchange resin with Ti0 ₂ (weight ratio of resin: 3:100) having a particle diameter of 0.02 μηη, polytetrafluoroethylene fiber modified by Ti0 ₂ (0.01 μm in diameter, 120 μm in length, and resin The weight ratio was 5:100. The mixture was prepared by melt extrusion to prepare a monolayer film, and then the film was treated at 250 ° C for 3 hours to obtain a 16# film having a crosslinked structure of the formula II.

A film A3 prepared in Example 3 was laminated on both surfaces of the 16# film, and subjected to hot pressing treatment at 120 ° C for 2 minutes, and then hydrolyzed and acidified to obtain a four-layer crosslinked perfluorosulfonic acid microporous film. The ion exchange membrane, i.e., the proton exchange membrane of the present invention, is referred to as A12. Example 13

The grease and the particle size of 0.01 μm Zr0 ₂ (the weight ratio to the resin is 9:100), the cyclodextrin-W (III) complex (the weight ratio to the resin is 0.034:100) are mixed and dispersed in the N-A A dispersion having a solid content of 30% by weight was formed in the pyrrolidone.

Take the thickness ΙΟμηι,

(1 = 3, D = H) The expanded polytetrafluoroethylene film subjected to surface phosphorylation modification was immersed in the above dispersion for about half an hour to form a film at 190 ° C (17 #膜).

The above perfluoro ion exchange resin is the same as the repeating unit.

The perfluoro ion exchange resin was mixed at a weight ratio of 1:5 and dispersed in DMSO to form a solution having a total resin content of 10% by weight, and Zr ₃ (P0 ₄ ) having a particle diameter of 0.05 μm was added to the solution. ₄ (weight ratio to resin is 12: 100), an organic ruthenium catalyst was further added, and a film was formed by a casting method, and a film was formed at 230 ° C to form a triazine crosslinked ring to obtain an 18 # film.

Two layers of 17# film and three layers of 18# film were alternately laminated and subjected to hot pressing to obtain a five-layer film having a thickness of 50 μm, that is, the proton exchange film of the present invention, which is referred to as A13. Example 14

Will repeat the unit as

The resin was mixed with the resin in the Example 9 in a weight ratio of 5:1, and Zr0 _{2 having a} particle diameter of 0.01 μm (weight ratio to resin of 6:100) was added to the mixed resin. A single layer film was prepared by melt extrusion, and the film was treated at 280 ° C for 3 hours to obtain a 19# film having a crosslinked structure of the formula V.

The film A3 prepared in Example 3 was stacked on both surfaces of the 19# film, and hot pressed at 120 ° C, followed by hydrolysis and acidification to obtain a seven-layer crosslinked perfluorosulfonic acid microporous membrane reinforcing film, that is, the proton of the present invention. Exchange membrane, denoted A14. Example 15

Will repeat the unit as

The perfluoro ion exchange resin was mixed with SiO ₂ having a particle diameter of 0.02 μm (weight ratio of 3:100 to the resin), and a single layer film was prepared by melt extrusion, and the film was treated at 280 ° C. The 20# film of the formula I was obtained in an hour.

A polytetrafluoroethylene microporous membrane with a thickness of 28 μm and a porosity of 75% surface-modified by sulfur trioxide was placed on both surfaces of the 20# membrane, and then heated at 12 (TC, then hydrolyzed to obtain four The layer cross-linked perfluorosulfonic acid microporous membrane reinforced membrane, that is, the proton exchange membrane of the present invention, is referred to as A15.

A 10 μm PTFE-modified polytetrafluoroethylene microporous membrane (porosity 80%, pore size 1 μm) was first immersed in a solution of 0.5 mol/L tungsten nitrate for 50 minutes, and then used. The tensioning device fixes the circumference of the device. 30% by weight of a perfluorosulfonic acid resin NMP solution (wherein the perfluorosulfonic acid resin is a resin mixed solution having the following structural formula, the weight ratio of the two structural resins is 4:1: ten CF ₂ CF ₂ -|~C: f¥, one

OCF ₂ CF ₂ CF ₂ S0 ₃ H , _EW=960 ;

a=12, b=5 , a,=b,=l x/(x+y)=0.5, y/(x+y)=0.5) sprayed on

1=1, D=Me)

The above polytetrafluoroethylene microporous membrane (porosity 80) modified by CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ S0 ₂ A and CF ₃ (h=0, i=2, A=OH) %, a pore size of 1 μm), to obtain a composite film having a thickness of 12 μm, that is, the proton exchange membrane of the present invention, which is referred to as A16

Example 17

The fat was mixed at a weight ratio of 2:1, and SiO ₂ having a particle diameter of 0.03 μm (the ratio of the total weight of the resin to 5:100) was added, and the film was formed by hot pressing. Then with a thickness of 18μηι, a porosity of 80%,

CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ S0 ₂ A

CF ₃ ( h=l , i=4, A=OH ) surface-modified expanded polytetrafluoroethylene microporous membrane (porosity 80%, pore size 1 micron) hot-pressed and immersed in NH ₃ DMF solution (concentration is 10% by weight) for 5 hours. Obtaining the crosslinked structure of the (I) species at 200 ° C Membrane. The membrane was treated with an alkali solution and an acid solution, and then immersed in a DMF solution of acetylacetone-Ir(III) (concentration: 0.1% by weight) to obtain a metal ion-bonded crosslinked membrane, that is, the proton exchange membrane of the present invention. Make A17. Comparative example 1

This comparative example is used to illustrate the comparison of existing proton exchange membranes and their preparation methods.

repeat

EW = 1100 perfluoro ion exchange resin with H ₃ PW ₁₂ 0 ₄ . A 3 wt% DMF solution was prepared in a ratio of 100:1, cast into a film, and the film was crosslinked by 50 KGy radiation to obtain a 20 μηι crosslinked structure of the ion film (21# film) of the first type (I).

, _£ ^ ₉₄₀ 's full

- The repeating unit is a fluoride ion exchange resin with 3⁄4 PW ₁₂ 0 ₄ . Press polymer with 3⁄4PW ₁₂ 0 ₄ . A film (22# film) having a thickness of ΙΟμηι was obtained by a casting method at a temperature of 170 ° C for 60 minutes by a mass ratio of 100:20 to 30% by weight of a DMSO solution.

The 2# film, 21# film, and 22# film were laminated and hot pressed, and then hot pressed with the film 2 obtained in Example 2 to obtain a microporous film three-layer crosslinked doped ion film having a thickness of 60 μm, which was recorded as Cl. Comparative example 2

This comparative example is used to illustrate the existing proton exchange membrane and its preparation method.

A 30 μη thick expanded polytetrafluoroethylene film (porosity 70%) was placed in a 10% by weight nafion® DMF solution for about 1 hour, and then the soaked film was dried on a hot plate (TC treatment for 60 min). A 30 micron thick microporous membrane enhanced ion exchange membrane was obtained, designated C2.

The 95 °C conductivity, tensile strength, hydrogen permeation current, and dimensional change rate of the proton exchange membranes C1 and C2 prepared in the proton exchange membranes A1-A17 obtained in Examples 1-17 and Comparative Examples 1 and 2 were measured. See Table 1. Among them, the test conditions of the two conductivity values are: T=95°C, saturated humidity, and T=25 °C, after drying the dryer for two days; the test method of tensile strength is the national standard method

(GB/T20042.3-2009); Hydrogen permeation current test method is electrochemical method

(Electrochemical and Solid-State Letters, vol. 10, Issue 5, B101-B104, 2007). Table 1

It can be seen from Table 1 that the 95 °C conductivity, tensile strength, hydrogen permeation current and dimensional change rate of the proton exchange membrane of the present invention are superior to those of the conventional microporous membrane enhanced multi-perfluorocrosslinking doping. Ionic membrane.

Claims

Profit demand

OOSMM

1. A HNI proton exchange membrane comprising 2-40 layers of a perfluoro ion exchange resin-based monolayer film, characterized in that at least one monolayer film comprises a surface-modified auxiliary proton-conducting substance, at least one layer The film contains a high-valent metal compound, at least one

The proton exchange membrane according to claim 1, wherein the surface-modified auxiliary proton conductive material is contained in an amount of 0.05 to 50 parts by weight, preferably 1 to 1 part by weight based on 100 parts by weight of the perfluoro ion exchange resin. 15 parts by weight; the content of the high-valent metal compound is 0.0001 to 5 parts by weight, preferably 0.001 to 1 part by weight.

The proton exchange membrane according to claim 1 or 2, wherein the crosslinked network structure is one or more of the formulae (1), (11), (111), (I:

Where G^PG ₂ is C

Wherein R is a methylene group or a perfluoromethylene group, and n is 0-10

The proton exchange membrane according to any one of claims 1 to 3, wherein the surface-modified auxiliary proton-conducting substance is an auxiliary proton conduction modified by a group having an ion exchange function and/or an acidic group. The auxiliary proton conductive material is selected from the group consisting of: an oxide, an orthophosphate, a polyphosphate, a polyacid, a polyacid salt, and a hydrate thereof, a silicate, a sulfate, a selenite, and an arsenide. Or one or more; preferably one or more of an oxide, an orthophosphate, a polyphosphate, a polyacid, and a polyacid salt, further preferably one of an oxide, an orthophosphate, and a polyphosphate A variety.

The proton exchange membrane according to any one of claims 1 to 4, wherein the high-valent metal compound is a highest valence state and a middle valence of W, Ir, Y, Mn, Ru, V, Ζ, and La elements. Nitrate, sulphate, carbonate, phosphate, acetate and combined double salt; the highest valence and intermediate valence of W, Ir, Y, Mn, Ru, V, Ζ and La Fine, crown ether, acetylacetone, nitrogen-containing crown ether and nitrogen-containing heterocycle, ethylenediaminetetraacetic acid, dimethylformamide and dimethyl sulfoxide complex; and W, Ir, Y, Mn, Ru, One or more of the highest valence state of the V, Ζη, and La elements and the oxide having a perovskite structure in the intermediate valence state.

The proton exchange membrane according to any one of claims 1 to 5, wherein the modified microporous membrane is selected from the group consisting of an organic polymer microporous membrane modified with a monomer having an ion exchange function, and particularly preferably a fluorocarbon polymer film having a pore diameter of 0.1 to 10 μm, preferably 0.1 to 1 μm; a thickness of 5 to 100 μm, preferably 5 to 30 μm; a porosity of 30 to 99%, preferably 70 to 97%; The ion exchange function monomer is sulfur dioxide, sulfur trioxide, and one of the following perfluorosulfonic acid monomer (Α), perfluorosulfonic acid monomer (Β), and perfluorosulfonic acid monomer (C). Or multiple: CF ₂ =CFO(CF ₂ †FO) _h (CF ₂ ) ₁ SO ₂ A

CF ₃ (A) CF ₂ =CFO(CF ₂ CFO) _j (CF ₂ ) _k C0 ₂ B

CF ₃ (B)

Wherein, h = 0-l, i = 1-5, in, Cl, Br, OH, oxymethyl or ONa; j = 0-1, k 1-5, B is methyl, H or ethyl; 1 = 1-5, 0 is 11, methyl or ethyl.

The proton exchange membrane according to any one of claims 1 to 6, wherein the proton exchange membrane comprises 2-20 layers, preferably 2-5 layers of a monolayer film based on a perfluoro ion exchange resin; The proton exchange membrane has a thickness of from 5 to 300 μm, preferably from 10 to 150 μm, more preferably from 10 to 50 μm.

The proton exchange membrane according to any one of claims 1 to 7, wherein the perfluoro ion exchange resin is a perfluoroolefin monomer, one or more functional group-containing perfluoroolefins The body is formed by copolymerization of one or more perfluoroolefin monomers containing a crosslinking site, or a mixture of the above copolymers, and has an EW value of from 600 to 1300, preferably from 700 to 1200. The method of preparing a proton exchange membrane according to any one of claims 1 to 8, characterized in that the method comprises:

(3) at least one step (2) is obtained by combining a single layer film with at least one layer of the modified microporous film, while selectively combining the single layer film obtained in the steps (1) and/or (2), and / or selectively using the solution or melt described in step (1) to form a monolayer film therein, such that the resulting composite film comprises 2-40 monolayer films, at least one of which has a surface modification The auxiliary proton conductive material, at least one single layer film contains modified fibers, and at least one single layer film contains a high-valent metal compound. 10. The method according to claim 9, wherein the intersection network structure is one or more of the structures shown by the formulas (1), ), (111), (IV), and (V):

Wherein R is methylene or perfluoromethylene, and n is 0-10

The method according to claim 9 or 10, wherein the method of forming the single layer film in the step (1) is casting, extrusion, hot pressing, spin coating, casting, screen printing, spraying, and dipping One or more; preferably, heat-treated at 30-300 ° C for 0.1-600 minutes, more preferably 100-200 ° C when cast, spin-coated, cast, screen-printed, spray-coated or impregnated. Heat treatment for 1-30 minutes. The method according to any one of claims 9 to 12, wherein the method of forming the cross-linked network structure represented by the formula (I) in the step (2) comprises: using heat, light, electron radiation, plasma , X-ray, a free radical initiator, and in the presence of one or more cross-linking agents, a cross-linked network structure is formed by the action of heat, light, electron radiation, plasma, X-ray, or a radical initiator, wherein The radical initiator is one or more of an organic peroxide and an azo initiator, preferably an organic oxide initiator, more preferably a perfluoroorganic peroxide; the structure of the crosslinking agent One or more of the structures shown in formula (VI):

^X 2 ^R f7 ^X 3 ( VI )

Wherein X ₂ and X ₃ are each independently CI, Br or I; 3⁄47 is perfluorodecyl or fluorochloroindenyl;

The method of forming the crosslinked network structure represented by the formulas (II) and (III) comprises: using a sulfonyl fluoride, a sulfonyl chloride, a sulfonyl bromide type resin with ammonia, hydrazine, an organic diamine or capable of releasing ammonia, hydrazine or organic Organic peroxide reaction of diamine;

The method of forming the crosslinked network structure represented by the formula (IV) comprises: treating the perfluorosulfonic acid resin with chlorosulfonic acid;

The method for forming the crosslinked network structure represented by the formula (V) comprises: treating a nitrile group-containing perfluorosulfonic acid resin, a perfluorosulfonyl fluoride resin, a sulfonyl chloride resin, and a sulfonyl bromide resin by heat or acid One or more of them.

The method according to any one of claims 9 to 13, wherein the surface-modified auxiliary proton conductive substance comprises an oxide modified by an inorganic dopant, an orthophosphate, a polyphosphate, a polyacid, Polyacid salts, silicates, sulfates, selenites and arsenides, preferably oxides, orthophosphates, polycondensed phosphates, polyacids and polyacid salts, more preferably oxides, orthophosphates and polycondensates Phosphate; the inorganic dopants are Si0 ₂ , Zr0 ₂ , Ti0 ₂ , BP0 ₄ , Zr ₃ (P0 ₄ ) ₄ , Zr(HP0 ₄ ) ₂ , HZr ₂ (P0 ₄ ) ₃ , Ti(HP0 ₄ ) One or more of ₂ and Zr ₂ H(P ₃ 0 ₁₍₎ ) ₂ ;

The high-valent metal compound is a nitrate, a sulfate, a carbonate, a phosphate, an acetate, and a combination of the highest valence state and the intermediate valence state of the elements of \¥, Ir, Y, Mn, Ru, V, Zn, and La. Double salt, W, Ir, Y, Mn, Ru, V, Ζ, and La elements of the highest valence state and intermediate valence of cyclodextrin, crown ether, acetylacetone, nitrogen-containing crown ether and nitrogen-containing heterocycle, ethylene Amine tetraacetic acid, dimethylformamide and dimethyl sulfoxide complex, and the highest valence state and intermediate valence state of W, Ir, Y, Mn, Ru, V, Ζ, and La elements with perovskite structure One or more of the oxides;

The modified microporous membrane is selected from the group consisting of an organic polymer microporous membrane modified with a monomer having an ion exchange function, particularly preferably a fluorocarbon polymer membrane having a pore diameter of 0.1 to 10 μm, preferably 0.2 to 3 μm; Is 5-100 μηι, preferably 5-30 μηι; porosity is 30-99%, preferably 70-97%; The monomer having ion exchange function is sulfur dioxide, sulfur trioxide, and one of perfluorosulfonic acid monomer (A), perfluorosulfonic acid monomer (B) and perfluorosulfonic acid monomer (C) having the following structure: Kind or more:

CF ₂ =CFO(CF ₂ CFO) _h (CF ₂ ) ₁ SO ₂ A

Where h = 0-l, i= l-5, A is F, Cl, Br, OH, oxymethyl or ONa; j = 0-1, k = 1-5, B is methyl, H or B Base; 1 = 1-5, 0 is 11, methyl or ethyl.

The method according to any one of claims 9 to 14, wherein the perfluoro ion exchange resin is a perfluoroolefin monomer, one or more functional group-containing perfluoroolefin monomers, and One or more perfluoroolefin monomers containing a crosslinking site are copolymerized, or a mixture of the above copolymers, having an EW value of from 600 to 1300, preferably from 700 to 1200.

Use of a proton exchange membrane as claimed in any one of claims 1 to 8 or prepared by the method of any one of claims 9 to 15 in a proton exchange membrane fuel cell.