CN101807703B - Intermediate-temperature proton exchange film of organic polysiloxane phosphonic acid group and preparation method thereof - Google Patents

Abstract

The invention relates to an organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane and a preparation method thereof. A kind of organopolysiloxane phosphonic acid base medium temperature proton exchange membrane, it is characterized in that it is made of gamma-(2,3-epoxypropoxy) propyltrimethoxysilane, 2-(3,4-epoxycyclohexyl ) ethyltrimethoxysilane and phosphonic acid alkoxysilane are prepared by sol-gel process, and each raw material γ-(2,3-glycidyloxy)propyltrimethoxysilane: 2 The molar ratio of -(3,4-epoxycyclohexyl)ethyltrimethoxysilane:phosphonoalkoxysilane is 1:1:1.5˜1:0.3:0.2. The medium-temperature proton exchange membrane has high proton conductivity at medium temperature and low humidity, can still conduct protons even under anhydrous conditions, has good flexibility, high mechanical strength, and has a long service life in medium-temperature fuel cells.

Description

A kind of organopolysiloxane phosphonic acid-based medium temperature proton exchange membrane and preparation method thereof

technical field

The invention belongs to the technical field of fuel cells, and relates to a medium temperature proton exchange membrane for a proton exchange membrane fuel cell and a preparation method thereof. the

Background technique

Proton exchange membrane fuel cell (PEMFC) will become an energy supply device closely related to human daily life because of its high efficiency and environmental protection. It will be the focus of people's research in the next few years or even a long period of time. As one of the key components of PEMFC, proton exchange membrane (PEM) has a great influence on the performance of PEMFC. the

At present, PEMFC generally uses Pt or Pt alloy as the catalyst, and uses perfluorosulfonic acid ion membrane (PFSI) as the exchange membrane. Perfluorosulfonic acid ion membrane (PFSI) has excellent performance when the working temperature is about 80°C, but in this temperature range, the Pt catalyst adsorbs more CO, which poisons the Pt catalyst and significantly reduces the performance of the battery. One of the effective ways to solve the problem of CO poisoning is to increase the operating temperature of the battery to above 100°C. However, on the one hand, at an operating temperature above 100°C, the PFSI film will dry up due to the large amount of volatilization of water, that is, the decrease in humidity, making its The sharp drop in conductivity leads to poor performance of PEMFC. At the same time, it is easy to degrade when used for a long time at a working temperature above 100°C. On the other hand, the PFSI membrane is too expensive, which also greatly hinders the widespread promotion and application of PEMFC. . In order to solve the above problems and make PEMFC truly a safe and reliable "civilian" product, people are committed to developing a proton exchange membrane with excellent performance at medium temperature (100°C-200°C) and low cost. the

At present, the research on medium temperature proton exchange membranes is very active at home and abroad, and there are various ways, among which heteropoly acids such as phosphotungstic acid (PWA), silicotungstic acid (STA) or zirconium phosphate [Zr(HPO ₄ ) ₂ .H ₂ O] as a non-aqueous proton conduction unit of medium-temperature proton exchange membrane is a major research focus, phosphoric acid is the electrolyte of phosphoric acid fuel cells, it has a high proton conductivity, and also has a good self-ionization performance , can conduct electricity under non-aqueous conditions, which has attracted great attention, such as phosphoric acid-doped polybenzimidazole (PBI) proton exchange membranes. Although the medium-temperature proton exchange membrane can maintain good electrical conductivity under the condition of high doping amount, high temperature and low relative humidity, the doping amount is limited because phosphoric acid is difficult to form chemical bonds with the polymer matrix material, and It will be lost with water during use, which will affect the long-term performance of the fuel cell, and when the dosage is high, the mechanical strength of the proton exchange membrane will also decrease. Therefore, how to anchor the non-aqueous proton conduction unit on the polymer matrix It should be the focus of further research on this type of mesophilic proton exchange membrane.

At present, a small number of research institutes in Japan and the United States are conducting research on medium-temperature proton exchange membranes using organic-inorganic hybrid materials as the polymer matrix. The main chain of the organic-inorganic hybrid material is a chain composed of silicon atoms and oxygen atoms alternately. Stable skeleton, the side chain is formed by linking the silicon atom of the main chain with an organic group such as methyl, phenyl or vinyl. Due to this special molecular structure and composition, it not only has the excellent properties of inorganic silica such as high and low temperature resistance, weather aging resistance, ozone resistance, electrical insulation, flame resistance, non-toxic, non-corrosive and physiological inertness, but also has organic high Molecular materials are easy to process, and can be made into products that can meet various purposes according to different requirements. Therefore, it is a good choice to use it as a matrix and add non-aqueous proton conduction units to prepare medium-temperature proton exchange membranes. Most of these proton exchange membranes use orthoethyl silicate (TEOS) and γ-(2,3-glycidoxy)propyltrimethoxysilane (GPTMS) as precursors, ethanol as a solvent, and various Non-aqueous proton-conducting units such as phosphoric acid, etc., are prepared by a sol-gel process. The prepared proton exchange membrane has a pseudo-polyethylene glycol network structure, which can provide a proton transfer channel for the non-aqueous proton conduction unit, but because the generally used proton conduction unit phosphoric acid is difficult to mix with organic-inorganic hybrid matrix materials Therefore, at medium temperature and low humidity, the medium temperature proton exchange membrane has disadvantages such as low electrical conductivity and poor mechanical strength. the

Contents of the invention

The object of the present invention is to provide an organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane with high proton conductivity and excellent mechanical properties under medium temperature and low humidity. the

Another object of the present invention is to provide a method for preparing an organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane.

In order to solve the technical problem proposed by the present invention, the technical solution adopted in the present invention is: a kind of organopolysiloxane phosphonic acid base medium temperature proton exchange membrane, it is characterized in that it is made of gamma-(2,3-glycidyloxy) Propyltrimethoxysilane (GPTMS), 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (EHTMS) and phosphonoalkoxysilane (PATOS) were prepared by sol-gel process The raw materials γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: phosphonoalkoxy The molar ratio of silane is 1:1:1.5 to 1:0.3:0.2. the

According to the above scheme, the phosphonic acid alkoxysilane is phosphonic acid ethyltrimethoxysilane, phosphonic acid phenylethyl trimethoxysilane, phosphonic acid trifluoroethyl trimethoxysilane, phosphonic acid isopropyl Trimethoxysilane, Phosphonic Acid Ethyltriethoxysilane, Phosphonic Acid Phenylethyltriethoxysilane, Phosphonic Acid Trifluoroethyltriethoxysilane, Phosphonic Acid Isopropyltriethoxysilane A sort of. the

According to such scheme, the preparation method of described phosphonic acid alkoxysilane comprises the following steps:

1) According to the molar ratio of hydrogen-containing siloxane: alkenyl phosphonic acid: platinum acetylacetonate: solvent = (1.5～2.5): (1.5～2.5): (1.5×10 ^-3 ～2.5×10 ^-3 ):( 10-20) Prepare raw materials;

2) Under the protection of nitrogen, add hydrogen-containing siloxane and platinum acetylacetonate into a reactor equipped with an electromagnetic stirring device and pre-baked and dried, and then irradiate with ultraviolet light while stirring for 10 to 20 minutes;

3) Make alkenyl phosphonic acid into a solution with a solvent, add it dropwise into the reactor under nitrogen protection and room temperature water bath cooling, and then continue to react for 1.0 to 1.5 hours;

4) gac is added in the solution after the reaction in step (3), the catalyst platinum acetylacetonate is removed by filtration, and then the solvent is removed by rotary evaporation to obtain a light yellow transparent viscous liquid;

5) Vacuum drying to obtain a phosphonic acid alkoxysilane product. the

According to the above scheme, the hydrogen-containing siloxane is triethoxyhydrogensilane or trimethoxyhydrogensilane. the

According to the above scheme, the particle size of the platinum acetylacetonate particles is less than 20 μm. the

According to the above scheme, the alkenyl phosphonic acid is any one of trifluorovinyl phosphonic acid, styryl phosphonic acid, vinyl phosphonic acid and isopropenyl phosphonic acid. the

According to the scheme, the solvent is any one of dehydrated ethanol, dehydrated methanol, Virahol and toluene. the

The above-mentioned preparation method of an organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane is characterized in that it comprises the steps:

1) Preparation of sol: according to each raw material γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: phosphonic acid group The molar ratio of the alkoxysilane is 1:1:1.5～1:0.3:0.2 Select the raw material, add it to the reactor, and then add the 6.0-7.0 methanol, then add deionized water with a molar ratio of 4.0-5.0 to γ-(2,3-glycidoxy)propyltrimethoxysilane, and stir at room temperature for 12-24 hours to obtain a stable and clear Sol;

2) Preparation of gel film: Pour the sol obtained in step 1) into a polytetrafluoroethylene mold plate, cover with aluminum foil, and perform gelation treatment at 65-70°C, that is, dehydration and dealcoholization for 12-24 hours, until the sol solution becomes When it becomes viscous, remove the aluminum foil and continue gelation for 40-60 minutes to obtain a gel film without macroscopic cracks;

3) Drying: vacuum-drying the gel film without macroscopic cracks obtained in step 2) to obtain an organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane.

The invention adopts phosphonic acid alkoxysilane as the proton conduction unit, which can form chemical bonds with the organopolysiloxane network during sol-gel, and strengthens the proton conductivity of the medium temperature proton exchange membrane at medium temperature and low humidity; Using γ-(2,3-glycidoxy)propyltrimethoxysilane (GPTMS) as the precursor of sol-gel, because GPTMS has a pseudo polyethylene glycol network structure after hydrolysis and polymerization, it can be non-aqueous The proton conduction unit provides a channel for proton transfer; using 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (EHTMS) as a precursor can make the synthesized proton exchange membrane have a longer organic chain, thereby The flexibility of the proton exchange membrane is greatly improved. the

Compared with existing foreign methods, the present invention has the following advantages:

1) The organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane prepared by this method has high proton conductivity at medium temperature and low humidity, and can still conduct protons even under anhydrous conditions. the

2) The organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane prepared by the method has good flexibility, high mechanical strength, and long service life in medium-temperature fuel cells. the

3) The fuel cell assembled with the organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane prepared by the method has a high working temperature, can greatly reduce the poisoning of the catalyst by CO, improve the activity of the catalyst, and thereby increase the output power of the fuel cell. the

Description of drawings

Figure 1 is a schematic structural diagram of an organopolysiloxane phosphonic acid-based intermediate temperature proton exchange membrane prepared in the present invention. the

Detailed ways

In order to better understand the present invention, the content of the present invention is further illustrated below in conjunction with the examples, but the content of the present invention is not limited to the following examples. the

Gamma-(2,3-epoxypropoxy)propyltrimethoxysilane (GPTMS), 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (EHTMS) used in the following examples and methanol are analytically pure, with a purity greater than 98% (wt%). the

The preparation method of the phosphonic acid ethyltrimethoxysilane used is as follows: according to the molar ratio of trimethoxy hydrogen siloxane: vinylphosphonic acid: platinum acetylacetonate: methanol is 1.5: 1.5: 1.5 × 10 ^-3 : 20 Weigh the raw materials. Under the protection of nitrogen, add accurately measured trimethoxyhydrogensilane and platinum acetylacetonate into a pre-baked and dried three-necked flask equipped with electromagnetic stirring, irradiate under ultraviolet light, and stir for 10 minutes at the same time; Methanol was made into a solution, which was added dropwise to the reactor under the protection of nitrogen and cooled by a water bath at room temperature, and then continued to react for 1.0 hour; adding activated carbon, stirring for 10 minutes, filtering to remove the catalyst platinum acetylacetonate, and then rotating to remove the solvent to obtain Pale yellow transparent viscous liquid; obtained by vacuum drying at 130°C for 1.0 hour.

Referring to the preparation method of phosphonic acid ethyl trimethoxysilane, select the raw materials according to the ratio of each raw material in the following table 1, experiments 1 to 7 can respectively prepare phosphonic acid phenylethyl triethoxysilane, phosphonic acid triethoxysilane, and phosphonic acid triethoxysilane. Fluoroethyltriethoxysilane, Isopropyltriethoxysilane Phosphonate, Ethyltriethoxyhydrogensiloxane Phosphonate, Phenylethyltrimethoxysilane Phosphonate, Trifluoroethyltrimethylphosphonate Oxysilane and isopropyltrimethoxysilane phosphonate are available for use. the

Table 1

experiment number The ratio of raw materials Experiment 1 The molar ratio of triethoxyhydrosilane: styrylphosphonic acid: platinum acetylacetonate: methanol = 1.5: 1.5: 1.5×10 ^-3 : 20 Experiment 2 The molar ratio of triethoxyhydrosilane: trifluorovinylphosphonic acid: platinum acetylacetonate: methanol = 1.5: 1.5: 1.5×10 ^-3 : 20 Experiment 3 The molar ratio of triethoxyhydrosilane: isopropenylphosphonic acid: platinum acetylacetonate: methanol = 1.5: 1.5: 1.5×10 ^-3 : 20 Experiment 4 Triethoxyhydrosiloxane: vinylphosphonic acid: platinum acetylacetonate: methanol molar ratio = 1.5: 1.5: 1.5×10 ^-3 : 20 Experiment 5 Trimethoxyhydrosilane: styrylphosphonic acid: platinum acetylacetonate: methanol molar ratio = 1.5: 1.5: 1.5×10 ^-3 : 20 Experiment 6 Trimethoxyhydrosiloxane: trifluorovinylphosphonic acid: platinum acetylacetonate: methanol molar ratio = 1.5: 1.5: 1.5×10 ^-3 : 20 Experiment 7 Trimethoxyhydrosilane: isopropenylphosphonic acid: platinum acetylacetonate: methanol molar ratio = 1.5: 1.5: 1.5×10 ^-3 : 20

Example 1

The specific steps of the preparation method of organopolysiloxane phosphonic acid-based medium temperature proton exchange membrane are as follows:

1) Preparation of sol: according to the raw materials γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: ethyl phosphonate The molar ratio of trimethoxysilane is 1.0: 1.0: 1.5. Select the raw material and add it to the reactor, then add methanol with a molar ratio of 7.0 to GPTMS, then add deionized water with a molar ratio of 5.0 to GPTMS, and stir at room temperature for 24 hours, a stable and clear sol was obtained;

2) Preparation of gel film: Pour the sol solution obtained in step 1) into a polytetrafluoroethylene mold plate, cover with aluminum foil, then put it into an oven, gelatinize at 65-70°C, that is, dehydration and dealcoholization for 12 hours, When the sol solution becomes viscous, remove the aluminum foil and continue to gel for 45 minutes to obtain a gel film without macroscopic cracks;

3) Drying: drying the gel film without macrocracks obtained in step 2) at 130° C. for 1 to 2 hours in vacuum to obtain an organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane. the

The schematic diagram of the structure of organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane is shown in Figure 1. The test results of its basic physical properties are listed in Table 2. the

Example 2

The specific steps of the preparation method of organopolysiloxane phosphonic acid-based medium temperature proton exchange membrane are as follows:

1) Preparation of sol: according to the raw materials γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: phosphonic acid benzene The molar ratio of ethyltriethoxysilane is 1.0:0.5:0.7, select the raw material, add it to the reactor, then add methanol with a molar ratio of 6.0 to GPTMS, then add deionized water with a molar ratio of 4.0 to GPTMS, room temperature Stir for 18 hours to obtain a stable and clear sol;

2) Preparation of gel film: Pour the sol solution obtained in step 1) into a polytetrafluoroethylene mold, cover with aluminum foil, then put it into an oven, and gel (dehydration and dealcoholization) at 65-70°C for 24 hours , until the sol solution becomes viscous, remove the aluminum foil and continue gelation for 50 minutes to obtain a gel film without macroscopic cracks;

3) Drying: drying the gel film without macrocracks obtained in step 2) at 130° C. for 1 to 2 hours in vacuum to obtain an organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane. the

The test results of its basic physical properties are listed in Table 2. the

Example 3

The specific steps of the preparation method of organopolysiloxane phosphonic acid-based medium temperature proton exchange membrane are as follows:

1) Preparation of sol: according to the raw materials γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: phosphonic acid trimethoxysilane The mol ratio of fluoroethyl triethoxysilane is 1.0: 1.0: 0.6, choose raw material, add in the reactor, then add the methyl alcohol that is 7.0 with GPTMS mol ratio, then add the deionized water that is 5.0 with GPTMS mol ratio, Stir at room temperature for 24 hours to obtain a stable and clear sol;

2) Preparation of gel film: Pour the sol solution obtained in step 1) into a polytetrafluoroethylene mold, cover with aluminum foil, then put it into an oven, and gelatinize (dehydration and dealcoholization) at 65-70°C for 12 hours , until the sol solution becomes viscous, remove the aluminum foil, and continue to gel for 60 minutes to obtain a gel film without macroscopic cracks;

3) Drying: The gel film without macroscopic cracks obtained in step 2) is vacuum-dried at 150° C. for 1 to 2 hours to obtain an organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane. the

The test results of its basic physical properties are listed in Table 2. the

Example 4

The specific steps of the preparation method of organopolysiloxane phosphonic acid-based medium temperature proton exchange membrane are as follows:

1) Preparation of sol: according to the raw materials γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: phosphonic acid iso The molar ratio of propyltriethoxysilane is 1.0: 0.3: 0.2, select raw materials, add in the reactor, then add the methanol that is 6.0 with GPTMS molar ratio, then add the deionized water that is 4.0 with GPTMS molar ratio, room temperature Stir for 12 hours to obtain a stable and clear sol;

2) Preparation of gel film: Pour the sol solution obtained in step 1) into a polytetrafluoroethylene mold, cover with aluminum foil, then put it into an oven, and gel (dehydration and dealcoholization) at 65-70°C for 18 hours , when the sol solution becomes viscous, remove the aluminum foil and continue to gel for 40 minutes to obtain a gel film without macroscopic cracks;

3) Drying: vacuum-dry the gel film without macroscopic cracks obtained in step 2) at 140° C. for 1 to 2 hours to obtain an organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane. the

The test results of its basic physical properties are listed in Table 2. the

Embodiment 5～8

Example The ratio of raw materials Example 5 γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: moles of phosphonic acid ethyltriethoxysilane Ratio=1.0:1.0:1.5 Example 6 γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: mole of phosphonic acid phenylethyltrimethoxysilane Ratio=1.0:1.0:1.5 Example 7 γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: phosphonic acid trifluoroethyltrimethoxysilane Molar ratio=1.0:1.0:1.5 Example 8 γ-(2,3-epoxypropoxy)propyltrimethoxysilane: 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane: mole of phosphonic acid isopropyltrimethoxysilane Ratio=1.0:1.0:1.5

According to the proportions of the raw materials in the above table, referring to the experimental method in Example 1, Examples 5-8 can respectively prepare organopolysiloxane phosphonic acid-based medium-temperature proton exchange membranes.

Table 2 Performance test results of organopolysiloxane phosphonic acid-based intermediate temperature proton exchange membranes prepared by different experimental methods

Note: The electrical conductivity of this type of medium-temperature proton exchange membrane reported in the current literature is 0.027S/cm at 130°C and 37% relative humidity. the

Table 2 illustrates: the organopolysiloxane phosphonic acid-based medium-temperature proton exchange membrane prepared by the present invention has higher proton conductivity (≥0.06S/cm ) and excellent mechanical properties (tensile strength ≥ 23.1MPa). the

Claims (3)

1. temperature proton exchange film in the organopolysiloxane phosphonate group, it is characterized in that: it prepares according to following preparation method:

1) preparation of colloidal sol: according to each raw material γ-(2; 3-epoxy third oxygen) propyl trimethoxy silicane: 2-(3, the 4-epoxycyclohexyl) ethyl trimethoxy silane: the mol ratio of phosphonate group alkoxy silane is to choose raw material in 1: 1: 1.5～1: 0.3: 0.2, adds in the reactor; Add and γ-(2 then; 3-epoxy third oxygen) the propyl trimethoxy silicane mol ratio is 6.0～7.0 methyl alcohol, and adding is 4.0～5.0 deionized water with γ-(2,3-epoxy third oxygen) propyl trimethoxy silicane mol ratio again; Stirring at room 12～24 hours must be stablized limpid colloidal sol;

2) preparation of gel mould: the colloidal sol that step 1) obtains is poured in the polytetrafluoroethylene mould, covered aluminium foil, 65～70 ℃ of gelations are handled; When sol solution becomes thickness; Remove aluminium foil again, continue gelation 40～60 minutes, obtain not having the gel mould of macroscopic cracking;

The gel mould vacuumize of the no macroscopic cracking that 3) drying: with step 2) obtains obtains temperature proton exchange film in the organopolysiloxane phosphonate group.

2. temperature proton exchange film in a kind of organopolysiloxane phosphonate group according to claim 1 is characterized in that: described phosphonate group alkoxy silane is any in phosphonic acids ethyl trimethoxy silane, phosphonic acids phenethyl trimethoxy silane, phosphonic acids trifluoroethyl trimethoxy silane, phosphonic acids isopropyl trimethoxy silane, phosphonic acids ethyl triethoxysilane, phosphonic acids phenethyl triethoxysilane, phosphonic acids trifluoroethyl triethoxysilane, the phosphonic acids isopropyl triethoxysilane.

3. the preparation method of temperature proton exchange film is characterized in that it comprises the steps: in a kind of organopolysiloxane phosphonate group as claimed in claim 1

1) preparation of colloidal sol: according to each raw material γ-(2; 3-epoxy third oxygen) propyl trimethoxy silicane: 2-(3, the 4-epoxycyclohexyl) ethyl trimethoxy silane: the mol ratio of phosphonate group alkoxy silane is to choose raw material in 1: 1: 1.5～1: 0.3: 0.2, adds in the reactor; Add and γ-(2 then; 3-epoxy third oxygen) the propyl trimethoxy silicane mol ratio is 6.0～7.0 methyl alcohol, and adding is 4.0～5.0 deionized water with γ-(2,3-epoxy third oxygen) propyl trimethoxy silicane mol ratio again; Stirring at room 12～24 hours must be stablized limpid colloidal sol;

2) preparation of gel mould: the colloidal sol that step 1) obtains is poured in the polytetrafluoroethylene mould, covered aluminium foil, 65～70 ℃ of gelations are handled; When sol solution becomes thickness; Remove aluminium foil again, continue gelation 40～60 minutes, obtain not having the gel mould of macroscopic cracking;

The gel mould vacuumize of the no macroscopic cracking that 3) drying: with step 2) obtains obtains temperature proton exchange film in the organopolysiloxane phosphonate group.

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