CN103531831B - Temperature proton exchange film material and preparation method thereof in a kind of soda acid type aminopolyphosphonic acid polysiloxanes - Google Patents

Abstract

The invention provides an acid-base type aminopolyphosphonic acid polysiloxane medium-temperature proton exchange membrane material and a preparation method thereof. The raw materials for preparing the membrane material include organic phosphonic acid and aminoalkoxysilane, and the molar ratio of the raw materials is For organic phosphonic acid: aminoalkoxysilane = 1:2-1:4. The acid-base amino polyphosphonic acid polysiloxane medium-temperature proton exchange membrane material has mild reaction conditions, high content of bonded phosphoric acid, and can effectively inhibit phosphoric acid exudation, high proton conductivity, and good performance under medium temperature and low humidity conditions. .

Description

A kind of acid-base type amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material and its preparation method

technical field

The invention belongs to the technical field of fuel cell manufacturing, and in particular relates to an acid-base amino polyphosphonic acid polysiloxane medium-temperature proton exchange membrane material, a preparation method thereof and a fuel cell prepared using the material.

Background technique

Proton exchange membrane fuel cell (PEMFC) is environmentally friendly, and has the advantages of small size and light weight. It is suitable for use as a mobile power source for portable electronic appliances. It is a hot spot in the field of energy research and development. Proton exchange membrane (PEM) is an important part of proton exchange membrane fuel cell. It not only plays the role of isolating fuel (such as CO) and oxidant to prevent them from reacting directly, but also plays the role of electrolyte. The performance of the proton exchange membrane significantly affects the output power and cell efficiency of PEMFC. At present, PEMFC generally uses Pt or Pt alloy as the catalyst, and uses perfluorosulfonic acid membrane (PFSI) represented by Nafion membrane as the exchange membrane. The perfluorosulfonic acid membrane (PFSI) has excellent performance when the working temperature is about 80°C, but in this temperature range, the catalyst adsorbs more CO in the fuel, which poisons the catalyst and significantly reduces the performance of the battery. One of the effective ways to solve this problem is to increase the operating temperature of the battery to above 100°C. Increasing the operating temperature of the proton exchange membrane fuel cell can also improve the kinetics of the anode and cathode, especially the oxygen reduction reaction of the cathode, thereby increasing the working efficiency of the cell. However, the conductivity of existing perfluorosulfonic acid membranes is strongly dependent on water content, which limits its application at temperatures higher than the boiling point of water (100 °C). Therefore, the development and research of proton exchange membrane materials that can be used at medium temperature (120-180 ° C) has become a hot spot in the development and research of PEMFC today.

Oxygenated acids such as phosphoric acid, sulfuric acid, and perchloric acid still show good proton conductivity under anhydrous conditions due to their high degree of self-dissociation. Among them, liquid phosphoric acid has a high degree of self-dissociation (7.4%), a large amount of H ⁺ exists in the system, and its diffusion rate is about 2×10 ^-5 cm ² /s, which is much higher than other acid systems. A nearly ideal proton carrier that combines high proton solubility and high proton transport rate. Phosphoric acid is used as the liquid electrolyte of the fuel cell, and it still has a high proton conductivity when the phosphoric acid fuel cell operates at a temperature of about 150-200°C. Therefore, it is a better choice to use phosphoric acid as the proton-conducting unit of the medium-temperature proton exchange membrane. Many researchers at home and abroad have prepared medium-temperature proton exchange membranes by mixing phosphoric acid into high-temperature-resistant polymer matrix materials, such as phosphoric acid-doped polybenzimidazole proton exchange membranes. It still has high proton conductivity, but its commercialization is limited due to high cost, and the interaction between phosphoric acid and polybenzimidazole is weak, which will cause phosphoric acid to seep out and affect the long-term performance of fuel cells. Therefore, how to anchor phosphoric acid on the polymer matrix is the focus of the next step in the research of this type of mesophilic proton exchange membrane. Masaki Kato et al. (Electrochimica Acta., 2007, 52, 5924), a researcher at Minkoya University in Japan, combined the hydroxyl group of phosphonoacetic acid, hydroxyethyl phosphoric acid, etc. with γ-(2,3-epoxypropoxy)propyltrimethoxy The epoxy group of silane (GPTMS) is ring-opened and bonded to prepare an organic-inorganic hybrid proton-conducting membrane. Compared with the GPTMS composite phosphoric acid membrane, the release of phosphoric acid in the membrane is greatly reduced, but due to the bonded COP bond is stable Poor performance, easily hydrolyzed at high temperature, seriously affecting its service life.

Contents of the invention

The technical problem to be solved by the present invention is to provide a kind of acid-base type amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material and its preparation method and the fuel cell prepared by using the material for the above-mentioned deficiencies in the prior art. The method has mild reaction conditions and simple process, and the prepared material has high phosphoric acid content, can effectively inhibit phosphoric acid exudation, and has excellent mechanical properties. The corresponding medium-temperature proton exchange membrane has high proton conductivity and good performance under medium-temperature and low-humidity conditions.

The technical scheme adopted to solve the technical problem of the present invention is to provide a kind of acid-base type amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material, and prepare the acid-base type amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material The raw materials include organic phosphonic acid and aminoalkoxysilane, and the molar ratio of the raw materials is organic phosphonic acid:aminoalkoxysilane=1:2-1:4.

Cross-linking is an important method to improve the physical and chemical properties of polymers. Properly cross-linked polymers are better than corresponding linear polymers in terms of mechanical strength, heat (cold) resistance, and chemical stability. The preparation of acid-base hybrid polymer membrane is one of the cross-linking methods. Phosphorus (phosphonic) acid is an amphoteric substance, which is both a proton donor and a proton acceptor. It also has a high electric double layer constant, so it has a high proton self-detachment ability, and it can be used as a proton-generating group , through the formation and breaking of intermolecular dynamic hydrogen bonds, protons jump between phosphoric acid molecules to complete proton transfer. It is an ideal proton conduction unit for proton transfer under high temperature and low humidity conditions. With phosphoric acid as the proton-conducting group and polysiloxane as the main structure, the synergistic effect between phosphorus and nitrogen can be used to accelerate the formation of phosphoric acid proton defects, that is, the self-detachment of phosphoric acid, and at the same time assist the hydrogen bonding between phosphoric acid molecules The formation of the network forms a continuous hydrogen bond network. Through the formation and breaking of continuous hydrogen bonds, the transfer of protons between phosphoric acid molecules is realized, which greatly reduces the dependence on water and achieves the purpose of high temperature and low humidity conduction.

Preferably, the organic phosphonic acid is one of aminotrimethylene phosphonic acid, hydroxyethylene diphosphonic acid or ethylenediamine tetramethylene phosphonic acid.

Preferably, the aminoalkoxysilane is one of 3-aminopropyltriethoxysilane or 3-aminopropyltrimethoxysilane. The amino group in the aminoalkoxysilane can react with organic phosphonic acid to form an acid-base reaction, which acts as an access to the phosphonic acid, and the aminoalkoxysilane can be hydrolyzed to form a Si-O network structure.

The present invention also provides a preparation method of the acid-base amino polyphosphonic acid polysiloxane medium-temperature proton exchange membrane material, the preparation method comprising the following steps:

(1) Dissolving organic phosphonic acid: dissolve 1 molar part of organic phosphonic acid in a solvent at room temperature to obtain an organic phosphonic acid solution;

(2) Add aminoalkoxysilane dropwise: Add 2-4 molar parts of aminoalkoxysilane dropwise to the organic phosphonic acid solution obtained in step (1) at a rate of 1-2 drops/second at 0-20°C In, the reactant mixture is obtained;

(3) Heat preservation: Stir the reactant mixture obtained in step (2) at 0-20°C and heat it for 24-48 hours to obtain nitrogen-containing polyphosphonic acid siloxane sol;

(4) Film formation: the nitrogen-containing polyphosphonic acid siloxane sol obtained in step (3) is gelled and dried to obtain an acid-base amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material.

In step (3), the -P(O)(OH) ₂ group on the organic phosphonic acid and the -NH ₂ group on the aminoalkoxysilane undergo an acid-base neutralization reaction in water, and the reaction mechanism is as follows:

The above step (3) reacts to generate nitrogen-containing polyphosphonic acid siloxane sol. The acid-base salinization reaction not only introduces the network structure, but also makes the prepared membrane material have good mechanical stability and high flexibility due to the interaction of intermolecular hydrogen bonds. Has less swelling and small molecule permeability.

In order to avoid the implosion of siloxane caused by the exothermic reaction of the neutralization reaction and the rise of the system temperature, it is necessary to control the reaction temperature at 0-20°C.

Preferably, the organic phosphonic acid in step (1) is one of aminotrimethylene phosphonic acid, hydroxyethylene diphosphonic acid or ethylenediamine tetramethylene phosphonic acid.

Preferably, the aminoalkoxysilane in step (2) is one of 3-aminopropyltriethoxysilane or 3-aminopropyltrimethoxysilane.

Preferably, the gelation treatment in step (4) includes aging at room temperature for 3-5 days and then vacuum drying at 0.02-0.08 MPa and 40-60° C. for 24-48 hours.

At room temperature, under the acidic environment provided by organic phosphonic acid, the Si-OC ₂ H ₅ in the nitrogen-containing polyphosphonic acid siloxane sol obtained in step (3) is hydrolyzed in water, and ethanol is released to form Si-OH, Afterwards, intermolecular dehydration condensation occurs to form a Si-O-Si crosslinked network structure. The reaction mechanism is as follows:

The gelled acid-base amino polyphosphonic acid polysiloxane is obtained, and finally dried to obtain the acid-base amino polyphosphonic acid polysiloxane medium-temperature proton exchange membrane material.

The present invention also provides a fuel cell prepared from the above-mentioned acid-base amino polyphosphonic acid polysiloxane medium-temperature proton exchange membrane material, which includes the acid-base amino polyphosphonic acid polysiloxane medium-temperature proton exchange prepared according to the above-mentioned preparation method The exchange membrane of the battery prepared by the membrane material.

The beneficial effects of the present invention are as follows: use a simple and easy-to-implement method to prepare fuel cell acid-base aminopolyphosphonic acid polysiloxane medium-temperature proton exchange membrane materials, enhance the compatibility of phosphoric acid and polymers through cross-linking reactions, and prevent phosphoric acid molecules Oozing out, improving the content of phosphoric acid in the exchange membrane material, has significant progress in improving the proton conductivity and medium temperature resistance stability of the proton exchange membrane material of the fuel cell. ) and low humidity (50% relative humidity) conditions, the proton conductivity can reach 0.059-0.072S/cm, and the acid-base amino polyphosphonic acid polysiloxane medium temperature proton exchange membrane material has a large tensile strength (27.5- 31.9MPa), with excellent toughness, thermal stability and chemical stability.

Detailed ways

In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below in conjunction with examples.

The embodiment of the present invention provides an acid-base type amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material for fuel cells with high proton conductivity.

Embodiment one

At room temperature (20°C), put 20mL of deionized water in a three-necked flask equipped with a stirring rod and a thermometer, put 2.99g of aminotrimethylene phosphonic acid into the three-necked flask, and stir at a rate of 600r/min until the amino The trimethylene phosphonic acid is completely dissolved to obtain an amino trimethylene phosphonic acid solution; then the three-necked flask is placed in an ice-water mixing bath, and 8.85 g of 3-aminopropyltriethyl Oxysilane (molar ratio aminotrimethylene phosphonic acid: 3-aminopropyltriethoxysilane = 1:4), kept stirring during the dropwise addition, and continued to stir for 24 hours after the dropwise addition, to obtain nitrogen-containing polyphosphine acid siloxane sol. The obtained nitrogen-containing polyphosphonic acid siloxane sol was poured into a polytetrafluoroethylene mold, aged at room temperature for 3 days, then vacuum-dried at 0.02 MPa at 40°C for 1 day, and then successively at 80°C Bake for 3 hours at 120°C, 2 hours at 120°C for 2 hours at 150°C to obtain a dried product film, and after cooling, peel the product film from the PTFE mold to obtain an acid-base aminopolyphosphonic acid polysiloxane Medium temperature proton exchange membrane material.

According to the electrochemical workstation test, the molar ratio of silicon to phosphorus in the acid-base aminopolyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material produced in this example is Si:P=1:0.74, at 120°C and a relative humidity of 25 Under the condition of %, the proton conductivity is 0.061S/cm, the ion exchange capacity is 0.64mg/mol, the tensile strength is 30.2Mpa, the linear swelling coefficient is 6.24%, the water absorption rate is 14.8%, and the use stability at 215°C good.

Embodiment two

Put 20mL of deionized water in a three-necked flask equipped with a stirring bar and a thermometer at room temperature (20°C), put 2.06g of hydroxyethylene diphosphonic acid in the three-necked flask, and stir at a rate of 700r/min Until the hydroxyethylene diphosphonic acid is completely dissolved to obtain a hydroxyethylene diphosphonic acid solution; then put the three-necked flask into a cold water bath at 8°C, and drop 8.85g of 3 - Aminopropyltriethoxysilane (molar ratio of hydroxyethylidene diphosphonic acid: 3-aminopropyltriethoxysilane = 1:4), keep stirring during the dropping process, and continue to Stir for 24 hours to obtain nitrogen-containing polyphosphonic acid siloxane sol. The obtained nitrogen-containing polyphosphonic acid siloxane sol was poured into a polytetrafluoroethylene mold, aged at room temperature for 4 days, then vacuum-dried at 0.04MPa at 50°C for 1 day, and then successively at 80°C Baking at 120°C for 2 hours at 120°C for 2 hours at 150°C for 2 hours to obtain a dried product film, and an acid-base aminopolyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material.

The acid-base amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material obtained in this example is tested by the same test method as in Example 1. The acid-base amino polyphosphonic acid polysiloxane produced in this example The molar ratio of silicon to phosphorus in the medium-temperature proton exchange membrane material is Si:P=1:0.93. The proton conductivity is 0.063S/cm and the ion exchange capacity is 0.70mg/mol at 120°C and 25% relative humidity. The tensile strength is 29.9Mpa, the linear swelling coefficient is 7.81%, the water absorption rate is 15.0%, and the use stability is good at 215°C.

Embodiment Three

Put 20mL of deionized water in a three-necked flask equipped with a stirring bar and a thermometer at room temperature (20°C), put 3.09g of hydroxyethylene diphosphonic acid in the three-necked flask, and stir at a rate of 800r/min Dissolve completely to hydroxyethylene diphosphonic acid, obtain hydroxyethylene diphosphonic acid solution; Then put the three-necked flask into the ice-water mixing bath, drop 7.17g of 3 - Aminopropyltrimethoxysilane (molar ratio hydroxyethylidene diphosphonic acid: 3-aminopropyltrimethoxysilane = 1.5:4), keep stirring during the dropwise addition, and continue to stir for 24h after the dropwise addition , to obtain nitrogen-containing polyphosphonic acid siloxane sol. The obtained nitrogen-containing polyphosphonic acid siloxane sol was poured into a polytetrafluoroethylene mold, aged at room temperature for 3 days, then vacuum-dried at 0.06MPa at 60°C for 1 day, and then successively at 80°C Baking at 120°C for 2 hours at 120°C for 2 hours at 150°C for 2 hours to obtain a dried product film, and an acid-base aminopolyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material.

The acid-base amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material obtained in this example is tested by the same test method as in Example 1. The acid-base amino polyphosphonic acid polysiloxane produced in this example The molar ratio of silicon to phosphorus in the medium-temperature proton exchange membrane material is Si:P=1:0.73. The proton conductivity is 0.059S/cm and the ion exchange capacity is 0.58mg/mol at 120°C and the relative humidity is 25%. The tensile strength is 31.9Mpa, the linear swelling coefficient is 5.48%, the water absorption rate is 13.1%, and the use stability is good at 210°C.

Embodiment Four

At room temperature (20°C), put 20mL of deionized water in a three-necked flask equipped with a stirring rod and a thermometer, put 4.36g of ethylenediaminetetramethylenephosphonic acid into the three-necked flask, and Stir at a high speed until the ethylenediaminetetramethylenephosphonic acid is completely dissolved to obtain an ethylenediaminetetramethylenephosphonic acid solution; then put the three-necked flask in a cold water bath at 5°C, and pour the three-necked flask into the three-necked flask at a rate of 2 drops/second Add 8.85g of 3-aminopropyltriethoxysilane dropwise (molar ratio ethylenediaminetetramethylenephosphonic acid: 3-aminopropyltriethoxysilane=1:4), keep Stir, and continue to stir for 24 hours after the dropwise addition to obtain a nitrogen-containing polyphosphonic acid siloxane sol. The obtained nitrogen-containing polyphosphonic acid siloxane sol was poured into a polytetrafluoroethylene mold, aged at room temperature for 3 days, then vacuum-dried at 0.08MPa at 60°C for 1 day, and then successively at 80°C Baking at 120°C for 6 hours, 120°C for 2 hours and 150°C for 2 hours to obtain a dried product film, and an acid-base aminopolyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material.

The acid-base amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material obtained in this example is tested by the same test method as in Example 1. The acid-base amino polyphosphonic acid polysiloxane produced in this example The molar ratio of silicon to phosphorus in the medium-temperature proton exchange membrane material is Si:P=1:1.73. The proton conductivity is 0.072S/cm and the ion exchange capacity is 0.79mg/mol at 120°C and 25% relative humidity. The tensile strength is 27.5Mpa, the linear swelling coefficient is 9.76%, the water absorption rate is 16.6%, and the use stability is good at 220°C.

Embodiment five

At room temperature (20°C), put 20 mL of deionized water in a three-necked flask equipped with a stirring bar and a thermometer, put 4.49 g of aminotrimethylene phosphonic acid into the three-necked flask, and stir at a rate of 700 r/min until the amino The trimethylene phosphonic acid is completely dissolved to obtain an amino trimethylene phosphonic acid solution; then the three-necked flask is placed in a 15°C cold water bath, and 7.17 g of 3-aminopropyl trimethoxy is added dropwise to the three-necked flask at a rate of 1 drop/second base silane (molar ratio aminotrimethylene phosphonic acid: 3-aminopropyltrimethoxysilane = 1.5:4), keep stirring during the dropwise addition, and continue to stir for 24 hours after the dropwise addition, to obtain nitrogen-containing silicon polyphosphonate Oxygen Sol. The resulting nitrogen-containing polyphosphonic acid siloxane sol was poured into a polytetrafluoroethylene mold, aged at room temperature for 3 days, then vacuum-dried at 0.05MPa and 50°C for 1 day, and then successively heated at 80 Baking at 120°C for 6 hours, 120°C for 2 hours and 150°C for 2 hours to obtain a dried product film, and to obtain an acid-base aminopolyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material.

The acid-base amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material obtained in this example is tested by the same test method as in Example 1. The acid-base amino polyphosphonic acid polysiloxane produced in this example The molar ratio of silicon to phosphorus in the medium-temperature proton exchange membrane material is Si:P=1:1.10. The proton conductivity is 0.064S/cm and the ion exchange capacity is 0.75mg/mol at 120°C and 25% relative humidity. The tensile strength is 29.7Mpa, the linear swelling coefficient is 8.12%, the water absorption rate is 15.2%, and the use stability is good at 230°C.

Embodiment six

At room temperature (20°C), put 20mL of deionized water in a three-necked flask equipped with a stirring bar and a thermometer, put 5.98g of aminotrimethylene phosphonic acid into the three-necked flask, and stir at a rate of 800r/min until the amino The trimethylene phosphonic acid is completely dissolved to obtain an amino trimethylene phosphonic acid solution; then the three-necked flask is placed in a 20°C cold water bath, and 8.85 g of 3-aminopropyltriethyl is added dropwise to the three-necked flask at a rate of 2 drops/second Oxysilane (molar ratio aminotrimethylene phosphonic acid: 3-aminopropyltriethoxysilane = 1:2), keep stirring during the dropwise addition, and continue to stir for 12h after the dropwise addition, to obtain nitrogen-containing polyphosphine acid siloxane sol. The resulting nitrogen-containing polyphosphonic acid siloxane sol was poured into a polytetrafluoroethylene mold, aged at room temperature for 2 days, then vacuum-dried at 0.08 MPa at 60°C for 1 day, and then successively at 80°C Baking at 120°C for 2 hours at 120°C for 2 hours at 150°C for 2 hours to obtain a dried product film, and an acid-base aminopolyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material.

The acid-base amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material obtained in this example is tested by the same test method as in Example 1. The acid-base amino polyphosphonic acid polysiloxane produced in this example The molar ratio of silicon to phosphorus in the medium-temperature proton exchange membrane material is Si:P=1:1.43. The proton conductivity is 0.068S/cm and the ion exchange capacity is 0.77mg/mol at 120°C and 25% relative humidity. The tensile strength is 29.3Mpa, the linear swelling coefficient is 8.91%, the water absorption rate is 16.1%, and the use stability is good at 225°C.

Embodiment seven

At room temperature (20°C), put 20mL of ethanol in a three-necked flask equipped with a stirring bar and a thermometer, put 2.99g of aminotrimethylene phosphonic acid into the three-necked flask, and stir at a rate of 800r/min until the aminotrimethylene The phosphonic acid was completely dissolved to obtain an aminotrimethylene phosphonic acid solution; then the three-necked flask was placed in a 10°C cold water bath, and 8.85 g of 3-aminopropyltriethoxy was added dropwise to the three-necked flask at a rate of 2 drops/second Silane (molar ratio aminotrimethylene phosphonic acid: 3-aminopropyltriethoxysilane = 1:4), keep stirring during the dropwise addition, and continue to stir for 12 hours after the dropwise addition, to obtain nitrogen-containing polyphosphonic acid silicon Oxygen Sol. The resulting nitrogen-containing polyphosphonic acid siloxane sol was poured into a polytetrafluoroethylene mold, aged at room temperature for 2 days, then vacuum-dried at 0.08 MPa at 60°C for 1 day, and then successively at 80°C Baking at 120°C for 2 hours at 120°C for 2 hours at 150°C for 2 hours to obtain a dried product film, and an acid-base aminopolyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material.

The acid-base amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material obtained in this example is tested by the same test method as in Example 1. The acid-base amino polyphosphonic acid polysiloxane produced in this example The molar ratio of silicon to phosphorus in the medium-temperature proton exchange membrane material is Si:P=1:0.74. The proton conductivity is 0.062S/cm and the ion exchange capacity is 0.65mg/mol at 120°C and 25% relative humidity. The tensile strength is 30.0Mpa, the linear swelling coefficient is 6.17%, the water absorption rate is 14.5%, and the use stability is good at 215°C.

Embodiment Eight

At room temperature (20°C), put 20mL of ethanol in a three-necked flask equipped with a stirring rod and a thermometer, put 5.98g of aminotrimethylene phosphonic acid into the three-necked flask, and stir at a rate of 800r/min until the aminotrimethylene The phosphonic acid is completely dissolved to obtain an aminotrimethylene phosphonic acid solution; then the three-necked flask is placed in an ice-water mixing bath, and 8.85 g of 3-aminopropyltriethoxy is added dropwise to the three-necked flask at a rate of 2 drops/second Silane (molar ratio aminotrimethylene phosphonic acid: 3-aminopropyltriethoxysilane = 1:2), keep stirring during the dropwise addition, and continue to stir for 12 hours after the dropwise addition, to obtain nitrogen-containing polyphosphonic acid silicon Oxygen Sol. The resulting nitrogen-containing polyphosphonic acid siloxane sol was poured into a polytetrafluoroethylene mold, aged at room temperature for 2 days, then vacuum-dried at 0.08 MPa at 60°C for 1 day, and then successively at 80°C Baking at 120°C for 2 hours at 120°C for 2 hours at 150°C for 2 hours to obtain a dried product film, and an acid-base aminopolyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material.

The acid-base amino polyphosphonic acid polysiloxane intermediate temperature proton exchange membrane material obtained in this example is tested by the same test method as in Example 1. The acid-base amino polyphosphonic acid polysiloxane produced in this example The molar ratio of silicon to phosphorus in the medium-temperature proton exchange membrane material is Si:P=1:1.41. The proton conductivity is 0.066S/cm and the ion exchange capacity is 0.78mg/mol at 120°C and 25% relative humidity. The tensile strength is 29.1Mpa, the linear swelling coefficient is 8.78%, the water absorption rate is 16.3%, and the use stability is good at 220°C.

From the above detailed description of the embodiments of the present invention, it can be understood that the present invention solves the problems of conventional medium-temperature proton exchange membrane materials, such as complex process, low phosphoric acid content, and easy seepage of phosphoric acid, which lead to low conductivity and undurability of the fuel cell proton exchange membrane. The ratio of Si:P in the exchange membrane material is 1:0.73-1:1.73, and the proton conductivity can reach 0.059-0.072S/cm. And it can withstand high temperature above 210°C, and its performance is stable under the conditions of medium temperature of 120°C and relative humidity of 25%. The overall performance is better than that of the medium temperature proton exchange membrane material prepared in the prior art.

It can be understood that, the above embodiments are only exemplary embodiments adopted for illustrating the principle of the present invention, but the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims (4)

1. prepare a method for temperature proton exchange film material in soda acid type aminopolyphosphonic acid polysiloxanes, it is characterized in that comprising the following steps:

(1) be dissolved with machine phosphonic acid: be at room temperature dissolved in solvent by the organic phospho acid of 1 molar part, obtain organic phospho acid solution;

(2) aminoalkoxysilane is dripped: be added drop-wise in step (1) gained organic phospho acid solution with the speed of 1-2 drop/sec by the aminoalkoxysilane of 2-4 molar part at 0-20 DEG C, obtain reactant mixed liquor;

(3) be incubated: step (2) gained reactant mixed liquor is stirred and is incubated 24-48 hour at 0-20 DEG C, obtains nitrogenous polyphosphonic acid siloxane sol;

(4) film forming: nitrogenous for step (3) gained polyphosphonic acid siloxane sol is also dry through gelation process, obtains temperature proton exchange film material in soda acid type aminopolyphosphonic acid polysiloxanes.

2. the method preparing temperature proton exchange film material in soda acid type aminopolyphosphonic acid polysiloxanes according to claim 1, it is characterized in that organic phospho acid described in step (1) is the one in Amino Trimethylene Phosphonic Acid, hydroxy ethylene diphosphonic acid or ethylenediamine tetramethylene phosphonic acid, described solvent is water or ethanol, and aminoalkoxysilane described in step (2) is the one in 3-aminopropyl triethoxysilane or 3-aminopropyl trimethoxysilane.

3. the method preparing temperature proton exchange film material in soda acid type aminopolyphosphonic acid polysiloxanes according to claim 1, it is characterized in that the described gelation process of step (4) comprise at room temperature ageing 3-5 days after vacuumize 24-48 hour at 0.02-0.08MPa vacuum degree, 40-60 DEG C again.

4. a proton exchanging film fuel battery, is characterized in that comprising temperature proton exchange film material in the soda acid type aminopolyphosphonic acid polysiloxanes prepared according to the arbitrary described preparation method of claim 1-3 and prepares the proton exchange membrane of battery.