Composite proton-conducting polymer material and method for its producing

Abstract

FIELD: chemistry.SUBSTANCE: invention relates to proton-conducting heterogeneous polymer compositions. Composite proton-conducting polymer material containing 44-36 wt.% of aromatic polyetheretherketone (PEKBFH), where n=161-169, and 56-64 wt.% of bifunctional cation exchange resin KU-1, and a method for producing the proposed composite proton-conducting polymer material are proposed.EFFECT: implementation of the purpose, which consists in obtaining a composite proton-conducting polymer material with high values of specific conductivity and thermal resistance.2 cl, 5 ex(PEKBFH)

Description

[0001] The invention relates to composite proton-conducting polymeric materials, in particular to film materials used in solid polymer fuel cells and a method for producing them.

[0002] One of the simplest ways to create proton-conducting polymer systems is to create composite materials containing a binding polymer matrix and ionic components. Such components typically contain polar functional groups that abstract a proton (sulfonic acid, phosphoric acid, carboxyl, and other polar groups).

[0003] A method for producing proton-conducting polymer membranes is known (Patent RU 2285557, B01D71 / 38 (2006.01), B01D71 / 52 (2006.01).

[0004] The patent uses polyvinyl glycidyl diester of ethylene glycol with proton-conducting sulfonic acid groups in the side chain.

[0005] The disadvantages of the method are the multi-stage nature of the polymer electrolyte production and the possibility of interaction of the resulting sulfonic acid fragments with the hydroxyl groups of polyvinyl alcohol included in the polymer base, which leads to a decrease in the sulfonic acid groups in the polymer and, accordingly, to a decrease in the proton conductivity of the membrane.

[0006] In the following work [Trofimov B.A., Ermakova T.G., Volkova L.I., Kuznetsova N.P., Myachina G.F., Chipanina N.N., Kanitskaya L.V., Vakulskaya T.I., Rokhin A.V., Mognonov D.M. Plastics. 2007. No. 1. Pp. 20-23], membranes based on a copolymer of vinyl chloride and vinyl butyl ether containing sulfonic acid groups are described.

[0007] The disadvantages of composites are low proton conductivity values ​​(from 1.0×10 -4 cm / cm up to 3.0×10 -4 Cm / cm) at room temperature.

[0008] In the article [Shagaeva N.S., Sultangareev R.G., Orkhokova E.A., Prozorova G.F., Dmitrieva G.V., Dambinova A.S., Stenina I.A., Yaroslavtsev A.B. Membranes and membrane technologies. 2011. No. 3. pp. 213-219] proton-conducting polymer membranes based on modified polyvinyl chloride containing sulfonic acid groups are proposed.

[0009] The disadvantages of the method are the low values ​​of proton conductivity of membranes from 2.0×10 -4 cm / cm up to 5.9×10 -3 Cm / cm in the temperature range of 45-100 °C and unsatisfactory physical and mechanical properties.

[0010] In patent RU 2643960, IPC B01D71 / 30 (2006.01); C08J5 / 22 (2006.01); H01M 8 / 02 (2006.01) proposes proton-conducting polymer membranes with high conductivity based on modified polyvinyl chloride containing sulfonic acid fragments, vinyl chloride units and dehydrochlorinated vinyl chloride units modified by sulfonation of polyvinyl chloride with chlorosulfonic acid in a 1,2-dichloroethane medium in the presence of a heat stabilizer (barium salts) at a temperature of 60 °C and vigorous stirring for 1 hour. The method for producing proton-conducting polymer membranes includes sulfonation of polyvinyl chloride with chlorosulfonic acid in the presence of a heat stabilizer, followed by rolling a mixture based on modified polyvinyl chloride containing sulfonic acid fragments, vinyl chloride units and dehydrochlorinated vinyl chloride and dioctyl phthalate units at a temperature of 100-120 °C for 20 minutes.The method for producing proton-conducting polymer membranes involves rolling a mixture based on a sulfonated polymer and dioctyl phthalate in a ratio of 1:0.4 for 20 minutes.

[0011] The disadvantages of the proposed method include the need for a sulfonation reaction of polyvinyl chloride, which releases highly toxic hydrogen chloride, and the need to roll the mixture at a temperature of 100-120°C. Furthermore, vinyl chloride units containing single carbon-carbon bonds will not have sufficiently high thermal properties.

[0012] RU Patent No. 2284214 proposes proton-conducting composite polymer membranes. The matrices used are copolymers of 1-vinyl-1,2,4-triazole with fluoroalkyl methacrylates, as well as aliphatic and aromatic polybenzimidazoles and polyamidobenzimidazoles; the thermosetting plastics are epoxy-containing copolyimides, polyaminoimide resin, pyrimidine-containing oligo-bis-itaconimide, and poly-bis-benzotriazoleimide resin. Polymer films were formed from the resulting mixed solutions, followed by thermal curing or UV irradiation, and then doped by immersion in aqueous solutions of orthophosphoric acid of varying concentrations. Thermal curing of the films is carried out by prolonged heating at 100÷230 °C.

[0013] The disadvantages of this method are the multi-stage nature, the lengthy time required, and the need to use high temperatures.

[0014] Various types of composite additives (in particular, cation exchangers and anion exchangers) are known from the prior art and are used in the creation of polymer proton-conducting systems. For example, in patent application No. 148906, IPC C08J5 / 22, heterogeneous ion-exchange membranes are produced by rolling a mixture of ion exchangers and a polymer binder on hot rollers, followed by reinforcing them with synthetic fabrics or fibers in a press.

[0015] Reinforcement of membranes using this method is carried out in a hydraulic press at a temperature of 130-140 °C for 30-40 minutes.

[0016] Such prolonged exposure to high temperatures leads to the degradation of ion exchange groups of ionites and a drop in the electrochemical properties of the membranes.

[0017] Furthermore, preparing membranes for pressing (preparing and assembling packages) is a very labor-intensive process requiring the work of several people, which significantly complicates and lengthens the technological process and, ultimately, increases the cost of the membranes.

[0018] In patent application No. 462848, IPC C08J1 / 34, a method for producing heterogeneous ion-exchange membranes by rolling a mixture of ion exchangers and a polymer binder with subsequent reinforcement of the membranes on a drum vulcanization press is proposed.

[0019] The essence of this method is that a rolled membrane film consisting of crushed resin and polyethylene is coated on both sides with a reinforcing material (for example, nylon, lavsan) and is fed by a conveyor to the surface of a drum press heated to 130-140°C, rotating at a speed of 0.10-0.15 m / min, and at a pressure of 5-10 kgf / cm 2 the membrane is reinforced.

[0020] The disadvantages of this method are insufficient mechanical strength, as well as low electrochemical properties, which makes their application in industry difficult.

[0021] The closest analogue is the production of ion-exchange membranes according to patent RU No. 2314322, C08J5 / 22 “Method for producing heterogeneous ion-exchange membranes”, published 10.01. 2008, Bulletin No. 1.

[0022] In the patent, heterogeneous ion-exchange membranes are produced by rolling a mixture of an ion exchange resin and a polymer binder, feeding the mixture to a calender, the roller temperature of which is 125-135°C. A reinforcing material is applied to the surface of the calendered film, and then a material is applied on top of this to prevent the film from sticking to the heating surface of the press. Reinforcement is carried out at a temperature of 140-150°C and a pressure of 180-200 kgf / cm. 2 and a conveyor belt speed of 80-90 m / h. The reinforcement time is determined by the specified speed. The reinforced membrane then passes through a bath filled with water, where it is freed from the anti-stick material.

[0023] The disadvantages of this method are the length of time, the need to use high temperatures and pressure, the complexity of the technological cycle for obtaining the composite, as well as the low temperature properties of the product.

[0024] The object of the present invention is to develop a new composite proton-conducting polymer material and a simple, economical method for producing it.

[0025] The stated objective is achieved in that the composite proton-conducting polymer material is obtained by mixing aromatic polyetheretherketone (PEEKBFC) based on 4,4'-dioxy-3,3',5,5'-tetrabromophthalophenone, 4,4'-difluorodiphenyl ketone and hexachlorobenzene of the formula:

[0026]

[0027] where n = 161÷169, and bifunctional cation exchanger KU-1, containing different acid groups (-SO3H, -OH), obtained by copolycondensation of phenol and p-phenol sulfonic acid with formaldehyde:

[0028]

[0029] In this case, the following ratios (mass %) of components in the composite material are taken:

[0030] KU-1 56 ÷ 64 PEKBFH 44 ÷ 36

[0031] Samples of composite proton-conducting polymer material are obtained by dissolving PECBPC in trichloromethane, swelling KU-1 in trichloromethane, then mixing them until a homogeneous suspension is formed, and removing the solvent. Trichloromethane grade "Ch" was used.

[0032] The following examples illustrate the method for producing a composite proton-conducting polymer material.

[0033] Example 1. Obtaining a composite proton-conducting polymer material consisting of 44 wt.% PECBPC and 56 wt.% KU-1.

[0034] Place 0.88 g of PECBPC in glass beaker 1 and add 10 ml of trichloromethane (5.58% solution). Place 1.12 g of KU-1 cation exchange resin in glass beaker 2 and add 10 ml of trichloromethane. Leave the beakers for 1 hour, until the PECBPC completely dissolves and the KU-1 cation exchange resin swells. Then, pour the contents of beakers 1 and 2 into glass beaker 3 and stir for three minutes until a homogeneous suspension forms. The resulting mixture is then poured into a Petri dish previously placed in a fume hood. After the solvent has completely evaporated, a film composite proton-conducting polymer material is obtained.

[0035] The specific conductivity of the composite material, measured by the four-probe Van der Pauw method at a frequency of 500 Hz, reaches 1.42 10 -1 Cm / cm. The temperature at which mass loss begins, according to thermogravimetric analysis, is 448 °C.

[0036] Example 2. Obtaining a composite proton-conducting polymer material consisting of 42 wt.% PECBPC and 58 wt.% KU-1.

[0037] Place 0.84 g of PECBPC in glass beaker 1 and add 10 ml of trichloromethane (5.34%). Place 1.16 g of KU-1 cation exchange resin in glass beaker 2 and add 10 ml of trichloromethane. Leave the beakers for 1 hour, until the PECBPC completely dissolves and the KU-1 cation exchange resin swells. Then, pour the contents of beakers 1 and 2 into glass beaker 3 and stir for three minutes until a homogeneous suspension forms. The resulting mixture is then poured into a Petri dish previously placed in a fume hood. After the solvent has completely evaporated, a film composite proton-conducting polymer material is obtained.

[0038] The specific conductivity of the composite material, measured by the four-probe Van der Pauw method at a frequency of 500 Hz, reaches 1.44 10 -1Cm / cm. The temperature at which mass loss begins, according to thermogravimetric analysis, is 449 °C.

[0039] Example 3. Obtaining a composite proton-conducting polymer material consisting of 40 wt.% PECBPC and 60 wt.% KU-1.

[0040] Place 0.8 g of PECBPC in glass beaker 1 and add 10 ml of trichloromethane. Place 1.2 g of KU-1 cation exchange resin in glass beaker 2 and add 10 ml of trichloromethane (5.1%). Leave the beakers for 1 hour, until the PECBPC completely dissolves and the KU-1 swells. Then, pour the contents of beakers 1 and 2 into glass beaker 3 and stir for three minutes until a homogeneous suspension forms. Then, pour the mixture into a Petri dish previously placed in a fume hood. After complete evaporation of the solvent, a film composite proton-conducting polymer material is obtained.

[0041] The specific conductivity of the composite material, measured by the four-probe Van der Pauw method at a frequency of 500 Hz, reaches 1.46 10 -1 Cm / cm. The temperature at which mass loss begins, according to thermogravimetric analysis, is 451 °C.

[0042] Example 4. Obtaining a composite proton-conducting polymer material consisting of 38 wt.% PECBPC and 62 wt.% KU-1.

[0043] Place 0.76 g of PECBPC in glass beaker 1 and add 10 ml of trichloromethane. Place 1.24 g of KU-1 cation exchange resin in glass beaker 2 and add 10 ml of trichloromethane (4.86% solution). Leave the beakers for 1 hour, until the PECBPC completely dissolves and the KU-1 swells. Then, pour the contents of beakers 1 and 2 into glass beaker 3 and stir for three minutes until a homogeneous suspension forms. Then, pour the mixture into a Petri dish previously placed in a fume hood. After complete evaporation of the solvent, a film composite proton-conducting polymer material is obtained.

[0044] The specific conductivity of the composite material, measured by the four-probe Van der Pauw method at a frequency of 500 Hz, reaches 1.47 10 -1 Cm / cm. The temperature at which mass loss begins, according to thermogravimetric analysis, is 452 °C.

[0045] Example 5. Obtaining a composite proton-conducting polymer material consisting of 36 wt.% PECBPC and 64 wt.% KU-1.

[0046] Place 0.72 g of PECBPC in glass beaker 1 and add 10 ml of trichloromethane. Place 1.28 g of KU-1 cation exchange resin in glass beaker 2 and add 10 ml of trichloromethane (4.62% solution). Leave the beakers for 1 hour, until the PECBPC completely dissolves and the KU-1 swells. Then, pour the contents of beakers 1 and 2 into glass beaker 3 and stir for three minutes until a homogeneous suspension forms. Then, pour the mixture into a Petri dish previously placed in a fume hood. After complete evaporation of the solvent, a film composite proton-conducting polymer material is obtained.

[0047] The specific conductivity of the composite material, measured by the four-probe Van der Pauw method at a frequency of 500 Hz, reaches 1.48 10 -1Cm / cm. The temperature at which mass loss begins, according to thermogravimetric analysis, is 453 °C.

[0048] As can be seen from the information provided, samples of composite proton-conducting polymer material exhibit fairly high values ​​of specific conductivity and thermal stability.

[0049] The technical result of the proposed invention consists in the development of a new composite proton-conducting polymer material and a simple, economical method for its production.

Claims

1. A composite proton-conducting polymer material containing, as a binder polymer matrix, an aromatic polyetheretherketone of the formula: (PEKBFH) where n = 161-169, and bifunctional cationite KU-1, and the quantitative ratio of the components in the polymer composition corresponds, mass %: KU-1 56-64 PEKBFH 44-36 2. A method for producing a composite proton-conducting polymer material according to paragraph 1, comprising mixing a polymer matrix and a cation exchanger, characterized in that a PECBPC polymer matrix is ​​used in the form of a solution in trichloromethane with a mass concentration of 4.62-5.58%, and a bifunctional cation exchanger KU-1 is used as the cation exchanger, wherein the swelling of KU-1 is carried out in trichloromethane for 1 hour, after which the components are mixed until a homogeneous suspension is formed, followed by evaporation of the solvent.

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