CN102206342B - Conductive polymer and its synthesis method, electroactive electrode whose surface is covered with said conductive polymer - Google Patents

Abstract

The invention relates to electric conduction polymer and a synthesis method thereof and an electroactive electrode with a surface covered with the electric conduction polymer. In the synthesis method for the electric conduction polymer, polybasic acid is used as a doping agent and a cross-linking agent, so that a monomer is polymerized to obtain electric conduction polymer hydrogel, wherein the monomer is at least one of pyrrole or a derivative of the pyrrole, thiophene or a derivative of the thiophene, phenylamine or a derivative of the phenylamine; and the acid group of the polybasic acid comprises a phosphate group or polybasic acid of which each molecule comprises more than two acid groups selected from at least one of a sulfonic acid group, nitroxyl or a carboxylic acid group and which has the molecular weight of less than or equal to 800. The molar ratio of the mole number of the acid group contained in the polybasic acid to the mole number of an electric conduction polymer monomer is preferably 1:12-12:1. The electric conduction polymer obtained by the synthesis method is covered by the surface of the electroactive electrode. The electric conduction polymer has a simple preparation method, and other impurities are not required to be led into the electric conduction polymer. The prepared electric conduction polymer hydrogel has high ionic conductivity, super hydrophilicity and high biological compatibility.

Description

Conductive polymer and its synthesis method, electroactive electrode whose surface is covered with said conductive polymer

technical field

The invention relates to a conductive polymer and its synthesis method, and an electroactive electrode whose surface is covered with the conductive polymer.

Background technique

Since MacDiarmid, Hideki Shirakawa, and Heeger invented conductive polymers and doped these polymers to achieve all-round performance regulation from insulator to metal state, a new field of chemistry and condensed matter physics has been created. In optoelectronics, The fields of electronics and electrochemistry generate a large number of application prospects. Conductive polymers have stable physical and chemical properties, high electrical conductivity, and electron-ion dual carrier conduction mechanism, so they are widely used as electrode materials for electrochemical sensors, energy storage and other devices. In addition, the conductivity of conductive polymers is related to variables such as redox state, pH, etc., and is widely used in smart materials such as sensors. In recent decades, conductive polymer hydrogels have been widely used in biosensors, chemical sensors, bioelectrodes, biobatteries, microbial fuel cells, microbial electrolysis cells, medical electrodes, artificial muscles, artificial organs, drug delivery and biofuels for the following reasons Areas such as batteries are receiving more and more attention:

1) The conductive polymer hydrogel has a nano-frame structure and a large enough solid-liquid contact area, which has enhanced electronic conductivity, ion and molecular diffusion effects, and is conducive to the transport of electrons in the device;

2) Compared with traditional metal electrodes, conductive polymer hydrogel has the characteristics and advantages of soft materials;

3) Conductive polymer hydrogels are biocompatible and closest to the biological tissue environment compared to all other materials.

So far, there are only limited ways to synthesize conductive polymer hydrogels, because the two prerequisites for hydrogel formation are difficult to satisfy: 1) the hydrophilicity of the polymer; 2) the chemical or Physical crosslinking.

Currently, conductive polymer hydrogels can be synthesized by the following methods:

1) Synthesis of conductive polymers in non-conductive polymer-based hydrogel templates (i.e., a composite material of non-conductive hydrogel and conductive polymers is formed);

2) an ionically cross-linked water-soluble conductive polymer gel formed by the interaction of iron or magnesium ions and a negatively charged polyelectrolyte dopant;

3) The cross-linked polyaniline forms a gel through the cross-linking reaction between the epoxy group and the amino group of the polyaniline.

However, all the above methods without exception introduce impurities or non-functional materials, such as metal ions or non-functional polymers. The disadvantage of these methods is that the conductivity, electrochemical activity or biocompatibility of the conductive polymer is reduced, and the detailed analysis is as follows: 1) by conducting the polymer with common hydrogel materials such as polyvinyl alcohol, polyethylene glycol, Chitosan, polyacrylamide, poly 2-hydroxyethyl methyl methacrylate, polyacrylic acid, sodium alginate hydrogel and other composite materials can synthesize biocompatible hydrogels. However, compounding with non-functional hydrogel materials will undoubtedly reduce the conductivity and electrochemical activity of the material, thereby reducing the performance of electrodes and sensors; 2) Interacting the negatively charged polyelectrolyte doped on the conductive polymer with metal ions And the cross-linking method introduces a large amount of metal ion impurities, which reduces the activity of biocompatibility and enzyme; 3) for the method of cross-linking by the amino and epoxy groups on the polyaniline main chain, the conductivity is greatly reduced. Conductivity of polymers. In conclusion, the existing synthetic methods cannot meet the application requirements of conductive polymers in biomedical engineering, biobatteries, microbial fuel cells and other fields.

Contents of the invention

The invention provides a method for synthesizing a conductive polymer, which is simple and does not need to introduce other impurities.

The present invention also provides the conductive polymer obtained by the above synthesis method.

The present invention also provides an electroactive electrode whose surface is covered with said conductive polymer.

The synthesis method of the conductive polymer is as follows: polyacid is used as a dopant and a crosslinking agent to polymerize monomers to obtain a conductive polymer hydrogel, and the monomers are pyrrole or its derivatives, thiophene or its derivatives , aniline or its derivatives, the acid group of the polybasic acid contains phosphoric acid group, or the polybasic acid contains at least 2 or more selected from sulfonic acid group, nitric acid group or carboxylic acid group in each molecule A polyacid with a molecular weight of the acid group ≤ 800.

The molar ratio of the molar number of acid groups contained in the polybasic acid to the conductive polymer monomer is preferably 1:12˜12:1, more preferably 2:1˜1:2.

Preferred polyacids are phytic acid, phosphoric acid, polyvinylphosphoric acid, N-sulfonic acid butyl-3-methylimidazolium hydrogensulfate, N-sulfonic acid butylpyridine hydrogensulfate or 1,2,4,5- At least one of benzene tetracarboxylic acids, wherein the structural formula of phytic acid is shown in formula i, and the structural formula of 1,2,4,5-benzene tetracarboxylic acid is shown in formula ii. More preferably, the polybasic acid is phytic acid.

The conductive polymer hydrogel is obtained by the conventional polymerization method of the monomer, for example, the conductive polymer hydrogel is obtained by chemical oxidation polymerization of the monomer under the action of an oxidizing agent. The oxidizing agent is at least one of persulfate, ferric chloride, copper chloride, silver nitrate, hydrogen peroxide, chloroauric acid or ammonium cerium nitrate.

The water content of the conductive polymer hydrogel is 30%-85%, preferably 34%-85%.

The synthetic method of described conducting polymer specifically can comprise the following steps:

(1) preparing a first solution comprising an oxidizing agent;

(2) preparing a second solution comprising monomers;

(3) mixing the first solution with the second solution to polymerize the monomers to obtain a conductive polymer hydrogel;

Wherein, in steps (1) and (2), the first solution is an aqueous solution, the second solution is an aqueous solution or an organic solution, and the polybasic acid is prepared in the first solution and/or the second solution.

The porous nanostructured conductive polymer can be obtained by purifying the obtained conductive polymer hydrogel and then drying it.

An electroactive electrode, the surface of which is covered with the conductive polymer obtained by the above synthesis method.

The preparation method of described electroactive electrode can specifically comprise the following steps:

(1) preparing a first solution comprising an oxidizing agent;

(II) preparing a second solution comprising monomers;

(III) mixing the first solution with the second solution;

(IV) using the method of spin coating, dip coating, casting, inkjet printing or screen printing, covering the mixed solution obtained in step (III) on the surface of the electrode carrier, and reacting to generate a conductive polymer hydrogel electrode structure;

Wherein, in steps (I) and (II), the first solution is an aqueous solution, the second solution is an aqueous solution or an organic solution, and the polybasic acid is prepared in the first solution and/or the second solution.

As shown in Fig. 1A, monomers such as aniline monomers can be polymerized together to form long-chain polyaniline structures. The amine groups of polyaniline can interact with acid groups (doped acid, DA) to form doped polyaniline salts, as shown in Fig. 1B. Both polypyrrole and polythiophene molecules can undergo similar acid doping reactions, as shown in Fig. 1C and Fig. 1. When the conductive polymer is doped with multifunctional doping acid, the conductive polymer forms a network cross-linked structure, as shown in Figure 2. After freeze-drying the conductive polymer hydrogel, its microstructure is a monolithic coral-like nanostructure. According to Fig. 1B, 2, 3, high-quality and uniform polyaniline hydrogels can be synthesized in large quantities by a simple chemical method using multifunctional doping acids (functionality > 3).

The preparation method of the conductive polymer of the present invention is simple, without introducing other impurities, and can quickly form hydrogel in an aqueous solution with high yield, and is suitable for mass production. On the other hand, conductive polymer hydrogels and monolithic nanostructured conductive polymer materials can be prepared into homogeneous thin films by dip-coating and spin-coating precursor methods. The hydrogel can be micropatterned by the method of inkjet printing precursors.

Conductive polymer hydrogels can form uniform monolithic coral-like nanostructures. During the polymerization, the selected multifunctional doping acid effectively promotes the gelation process. The conductive polymer is doped with multifunctional doping acid, and the same multifunctional doping acid molecule interacts with multiple polymer chains, so the conductive polymer is cross-linked to form a three-dimensional network structure. The multi-component doping acid is beneficial to make the surface of the conductive polymer hydrophilic, so that the three-dimensional network structure of the conductive polymer can hold water and form a gel. When the gel is dried, the space occupied by its moisture is volatilized, and the molecular chain of the conductive polymer is a rigid chain so that its three-dimensional network structure will not collapse, and finally the conductive polymer forms an interconnected coral-like porous nanostructure. It should be pointed out that the as-prepared hydrogel is composed of pure doped conducting polymers rather than forming composite materials, thus the conductivity and electrochemical activity of conducting polymers are preserved. In the whole synthesis, no metal ions are used, which makes the hydrogel highly biocompatible, suitable for biosensors, biofuel cells, biobatteries, microbial fuel cells, microbial electrolysis cells, artificial muscles, artificial organs, drugs Release and other fields of application.

We found that the synthesized hydrogel has a three-dimensional porous nanostructure composed of branched fibrous structures, as shown in Figures 4A and 4B, where the BET surface area of the gel after drying is greater than 30 m ² ·g ^-1 . The prepared conductive polymer hydrogel has a high ion conductivity of about 0.017-0.026 S·cm ^-1 . The conductive polymer hydrogel has a contact angle of less than 15° and is superhydrophilic. Conductive polymer hydrogels have good biocompatibility.

Description of drawings

Fig. 1A Schematic diagram of the molecular structure of polyaniline emeraldine.

Fig. 1B Schematic diagram of the molecular structure of polyaniline emeraldine salt in the doped state. DA refers to doping acid.

Fig. 1C Schematic diagram of the molecular structure of acid-doped polypyrrole salts.

Fig. 1D Schematic diagram of the molecular structure of acid-doped polythiophene (PEDOT).

Fig. 2 is a schematic diagram of the formation mechanism of conductive polymer hydrogels. Under the action of multifunctional doping acid, the conductive polymer chains are cross-linked to form a conductive polymer hydrogel.

Fig. 3 A schematic diagram of the synthesis of conductive polymer hydrogels.

Fig. 4A SEM image of polyaniline hydrogel after lyophilization.

Fig. 4B Magnified SEM image of polyaniline hydrogel after lyophilization.

Fig. 5 SEM image of polypyrrole hydrogel after freeze-drying.

Fig. 6 SEM image of polythiophene hydrogel after lyophilization.

Fig. 7 SEM images of polyaniline hydrogel films formed by spin coating.

Fig. 8A SEM image of bovine bone marrow stem cells grown on phytic acid-doped polyaniline hydrogel.

Fig. 8B Magnified SEM image of bovine bone marrow stem cells grown on phytic acid-doped polyaniline hydrogel.

Fig.9 Fluorescence microscope image of bovine bone marrow stem cells grown on polyvinyl phosphate-doped polypyrrole hydrogel.

Fig. 10 Sensing characteristic curve of phytic acid-doped polyaniline hydrogel glucose oxidase electrode for glucose.

Detailed ways

The synthesis method of conductive polymer is as follows:

Step 1, prepare a solution consisting of water and an oxidizing agent. The oxidizing agent is preferably ammonium persulfate, but other oxidizing agents are also used such as ferric chloride, copper chloride, silver _nitrate , hydrogen peroxide, _chloroauric acid and other persulfate derivatives such as _Na2S2O8 and K ₂ S ₂ O ₈ .

Step 2, dissolving the monomer and acid in water or an organic solvent to form a monomer solution. In the example it is the monomer aniline, but other carbon-based organic monomers can also be used, such as pyrrole, thiophene and aniline derivatives such as anisole, methylaniline, ethylaniline, o-alkoxyaniline and 2 , 5-dialkoxyaniline monomer, which can be used to synthesize polypyrrole, polythiophene, polymethoxyaniline, polymethylaniline, polyethylaniline, polyalkoxyaniline aniline, poly2,5- Dialkoxyaniline, etc. The effect of multi-component doping acid is best for phytic acid, phosphoric acid and polyvinyl phosphoric acid containing phosphoric acid groups, but other small molecular acids with multi-functionality (functionality ≥ 2, molecular weight ≤ 800, the functionality refers to the The number of acid groups contained in the polybasic acid) can also be used, such as 1,2,4,5-benzenetetracarboxylic acid, N-sulfonic acid butyl-3-methylimidazolium bisulfate, N-sulfonic acid butyl Pyridine bisulfate, etc. The reaction can be carried out by single-phase aqueous solution synthesis or interfacial polymerization (organic solvent-water two-phase interface synthesis). In the interfacial polymerization reaction, carbon tetrachloride (CCl ₄ ) is used as the organic solvent, but other organic solvents that are not miscible with water can also be used, such as benzene, toluene, chloroform, methylene chloride, xylene, n-hexane, diethyl ether , dichloromethane and carbon disulfide. In embodiments, the aniline monomer and phytic acid are soluble in water when combined.

Step 3, placing the monomer solution in the reaction vessel. The capacity of the container can be large or small according to the actual needs. The large-scale container can be used to realize the mass production of polymer hydrogel, and it can also be cast into various shapes of hydrogel materials in containers of different shapes.

Step 4, mixing the oxidizing agent solution with the monomer solution.

Step 5, standing still (from several minutes to several days), the polyaniline hydrogel is formed in the water phase within a few minutes, and it can be observed that the color of the aqueous solution turns dark green at the same time.

Step 6, purification of the hydrogel. Excess ions are removed by dialysis or ion exchange of the hydrogel material in deionized water, distilled water. Finally, phytic acid-doped polyaniline pure hydrogel was obtained. In this step, the hydrogel can also be de-doped with ammonia to remove phytic acid. De-doping will not destroy the hydrogel structure, because the porous polyaniline backbone can already retain its shape. Whether a hydrogel is formed can be verified by an inversion experiment (cited literature: Metal-and Anion-Binding Supramolecular Gels, Chem.Rev.2010, 110, 1960-2004.), that is, the container is turned upside down, and the aqueous solution does not have Liquidity is considered to form a hydrogel. "The solution loses fluidity" in the inversion test of the examples of this patent refers to turning the container upside down, and no obvious solution flow behavior that can be clearly distinguished by the naked eye is observed within 30 minutes.

A embodiment: homogeneous reaction

Embodiment 1: Phytic acid (functionality 6, containing 6 phosphate radicals) doped polyaniline hydrogel

First configure 20 ml of ammonium persulfate oxidant aqueous solution with a concentration of 2M, and configure 25 ml of monomer aqueous solution mixed with aniline and phytic acid. The ratio of the amount of substances is ammonium persulfate: aniline: phytic acid=3:6:1. The two solutions are then mixed, and within minutes, polymerization occurs to produce a polyaniline hydrogel. It was observed that the color of the solution changed to dark green and the solution lost fluidity. Finally, dialysis was performed in deionized water to purify the hydrogel to remove impurities such as ions and oligomers to obtain a hydrogel with a water content of 72%. In this reaction, the mixing ratio of the reagents can be changed within a certain range (for example: the ratio of the amount of phosphoric acid groups contained in aniline and phytic acid can form a gel in the range of 1:12 to 12:1; persulfuric acid The ratio of ammonium to aniline monomers can be varied in a wide range; the concentration of reagents can be varied within a certain range to obtain conductive polyaniline hydrogels with a water content of 35% to 85%). The contact angle of the hydrogel obtained in this example is less than 15°, which is superhydrophilic. The hydrogel has a high ion conductivity of 0.025S·cm ^-1 as measured by chemical impedance spectroscopy. After freeze-drying, the hydrogel is observed under a scanning electron microscope as a coral-like monolithic porous nanomaterial composed of dendritic fibers (as shown in Figure 4), with a specific surface area > 30m ² ·g ^-1 . The grown phytic acid-doped polyaniline hydrogel has good biocompatibility, as shown in Figure 5, bovine bone marrow stem cells grown on the surface of the hydrogel. The freeze-dried powder of the gel was pressed into blocks, and its conductivity was tested by the standard four-probe method to be 0.02S·cm ^-1 . At 2000RPM, the precursor solution was spin-coated to form a uniform green transparent conductive polyaniline hydrogel film.

Embodiment 2: Phytic acid doped polyaniline hydrogel (water content 34%)

First prepare 1ml of ammonium persulfate oxidizing agent aqueous solution containing 0.286g, and configure the monomer aqueous solution mixed with aniline (0.458ml) and phytic acid (0.921ml) (the concentration can be deduced from the water content of the hydrogel). The two solutions are then mixed, and within minutes, polymerization occurs to produce a polyaniline hydrogel. It was observed that the color of the solution changed to dark green and the solution lost fluidity. A hydrogel with a water content of 34% was obtained. The ionic conductivity of the obtained hydrogel was 0.030 S·cm ^-1 .

Embodiment 3: Phytic acid doped polyaniline hydrogel (water content 85%)

First configure 2.5 ml of ammonium persulfate oxidant aqueous solution containing 0.286 g, and configure 6.5 ml of monomer aqueous solution mixed with aniline (0.458 ml) and phytic acid (0.921 ml). The two solutions are then mixed, and within minutes, polymerization occurs to produce a polyaniline hydrogel. It was observed that the color of the solution changed to dark green and the solution lost fluidity. A hydrogel with a water content of 85% was obtained. The ionic conductivity of the obtained hydrogel was 0.017 S·cm ^-1 .

Embodiment 4: Phytic acid doped polyaniline hydrogel (phosphate in phytic acid: aniline monomer molar ratio=1: 12)

First configure 20 ml of ammonium persulfate oxidant aqueous solution with a concentration of 2M, and configure 25 ml of monomer aqueous solution mixed with aniline and phytic acid. The ratio of the amount of substances is ammonium persulfate: aniline: phytic acid=18:72:1. The two solutions were then mixed, and after 24 hours, a polyaniline hydrogel was slowly formed. The time required increases because the content of phytic acid, which contributes to the formation of cross-linked structures, decreases and the critical conditions for hydrogel formation are soon exceeded. It can be observed that the color of the solution turns khaki (reflecting that the degree of doping of polyaniline is very small, compared with dark green, indicating that polyaniline is not fully doped due to too little amount of phytic acid), and the solution loses fluidity.

Embodiment 5: Phytic acid doped polyaniline hydrogel (aniline monomer: phosphate root molar ratio in phytic acid=1: 12)

First configure 20 ml of ammonium persulfate oxidant aqueous solution with a concentration of 2M, and configure 25 ml of monomer aqueous solution mixed with aniline and phytic acid. The ratio of the amount of substances is ammonium persulfate: aniline: phytic acid=1:2:4. The two solutions were then mixed, and after 12 hours, a polyaniline hydrogel was formed. The time required is longer because the amount of phytic acid exceeds that required for polyaniline doping, and excess free phytic acid molecules in solution that have not reacted with aniline hinder gel formation. It was observed that the color of the solution changed to dark green and the solution lost fluidity.

Example 6: 1,2,4,5-benzenetetracarboxylic acid (functionality 4, containing 4 carboxylate groups) doped polyaniline hydrogel

First configuration concentration is 20ml of ammonium persulfate oxidant aqueous solution 2M, and configuration aniline and 1,2,4,5-benzenetetracarboxylic acid mixed monomer aqueous solution 25ml, the ratio of substance amount is ammonium persulfate: aniline: 1, 2,4,5-Benzene tetracarboxylic acid = 2:4:1. The two solutions are then mixed, and within minutes, polymerization occurs to produce a polyaniline hydrogel. It was observed that the color of the solution changed to dark green, and the solution lost fluidity and became jelly-like. Finally, dialysis was performed in deionized water to purify the hydrogel to remove impurities such as ions and oligomers to obtain a hydrogel. The freeze-dried powder of the gel was pressed into a block, and its electrical conductivity was 0.0026S·cm ^-1 as tested by the standard four-probe method. Carboxylic acids are less acidic, so doped polyaniline has lower conductivity.

Embodiment 7: Phosphoric acid (comprising 3 H+) doped polyaniline hydrogel

First configuration concentration is 20ml of ammonium persulfate oxidant aqueous solution of 2M, and configuration monomer water-soluble 25ml that aniline and phosphoric acid mixes, the ratio of the amount of substance is ammonium persulfate: aniline: phosphoric acid=1:2:2. The two solutions are then mixed, and within minutes, polymerization occurs to produce a polyaniline hydrogel. It was observed that the color of the solution changed to dark green and the solution lost fluidity. Finally, dialysis was performed in deionized water to purify the hydrogel to remove impurities such as ions and oligomers to obtain a hydrogel. The freeze-dried powder of the gel was pressed into blocks, and its conductivity was tested by the standard four-probe method to be 0.031S·cm ^-1 .

Example 8: N-sulfonic acid butyl-3-methylimidazolium bisulfate (functionality 2, containing 1 sulfonate and 1 hydrogensulfate ion at both ends of the molecule) doped polyaniline hydrogel

First configuration concentration is 20ml of ammonium persulfate oxidizing agent aqueous solution 20ml, and the monomer aqueous solution 25ml that configuration aniline and N-sulfonic acid butyl-3-methylimidazolium bisulfate mixes, the ratio of substance amount is ammonium persulfate: aniline : N-sulfonic acid butyl-3-methylimidazolium bisulfate = 1:2:1. The two solutions are then mixed, and within minutes, polymerization occurs to produce a polyaniline hydrogel. It was observed that the color of the solution changed to dark green, and the solution lost fluidity and became jelly-like. Finally, dialysis was performed in deionized water to purify the hydrogel to remove impurities such as ions and oligomers to obtain a hydrogel. The freeze-dried powder of the obtained gel was pressed into blocks, and its conductivity was tested by a standard four-probe method to be 0.13 S·cm ^-1 .

Example 9: Polyvinylphosphoric acid doped polyaniline hydrogel

First configure 20 ml of ammonium persulfate oxidant aqueous solution with a concentration of 2M, and configure 25 ml of monomer aqueous solution mixed with aniline and polyvinyl phosphoric acid. The ratio of the amount of substances is ammonium persulfate: aniline: the amount of phosphoric acid groups in polyvinyl phosphoric acid =1:2:2. The two solutions are then mixed, and within minutes, polymerization occurs to produce a polyaniline hydrogel. It was observed that the color of the solution changed to dark green and the solution lost fluidity to form a gel. Finally, dialysis was performed in deionized water to purify the hydrogel to remove impurities such as ions and oligomers to obtain a polyvinylphosphoric acid-doped polyaniline hydrogel. The freeze-dried powder of the gel was pressed into a block, and its electrical conductivity was 0.018S·cm ^-1 as tested by the standard four-probe method.

Embodiment 10: Phytic acid (functionality 6, containing 6 phosphate radicals) doped polypyrrole hydrogel

First configuration concentration is 20ml of ammonium persulfate oxidizing agent aqueous solution of 2M, and configuration pyrrole, ethylene glycol and phytic acid mixed monomer aqueous solution 25ml (the purpose of additive ethylene glycol is to increase the solubility of pyrrole, and the consumption of ethylene glycol is: with water volume ratio 1:10), the ratio of the amount of substance is ammonium persulfate:pyrrole:phytic acid=3:6:1. Then the two solutions are mixed, the polymerization reaction takes place, and the polypyrrole hydrogel is rapidly produced. It was observed that the color of the solution changed to black and the solution lost fluidity. Finally, the polypyrrole hydrogel was obtained by dialysis in deionized water to purify the hydrogel to remove impurities such as ions, oligomers, and ethylene glycol. The freeze-dried powder of the obtained gel was pressed into a block, and its electrical conductivity was 4.3 S·cm ^-1 as tested by the standard four-probe method.

Example 11: Phytic acid doped poly 2-(2-hydroxyethyl)thiophene hydrogel

First configuration concentration is 20ml of ammonium persulfate oxidant aqueous solution of 2M, and configuration 2-(2-hydroxyethyl) thiophene and phytic acid mixed monomer aqueous solution, the ratio of substance amount is ammonium persulfate: 2-(2-hydroxyl Ethyl)thiophene:phytic acid=3:6:1. The two solutions are then mixed, and within minutes, polymerization occurs to produce a polyaniline hydrogel. It was observed that the color of the solution changed to dark blue and the solution lost fluidity to form a gel. Finally, dialysis is performed in deionized water to purify the hydrogel to remove impurities such as ions and oligomers to obtain a hydrogel of poly 2-(2-hydroxyethyl)thiophene. The freeze-dried powder of the obtained gel was pressed into blocks, and its electrical conductivity was 5.6 S·cm ^-1 as tested by the standard four-probe method.

Example 12: Phosphoric acid doped poly 2-(2-hydroxyethyl)thiophene hydrogel

First configuration concentration is 20ml of ammonium persulfate oxidant aqueous solution of 2M, and configuration 2-(2-hydroxyethyl) thiophene and phytic acid mixed monomer aqueous solution, the ratio of substance amount is ammonium persulfate: 2-(2-hydroxyl Ethyl)thiophene:phosphoric acid=1:2:2. The two solutions are then mixed, and within minutes, polymerization occurs to produce a polyaniline hydrogel. It was observed that the color of the solution changed to dark blue and the solution lost fluidity to form a gel. Finally, dialysis is performed in deionized water to purify the hydrogel to remove impurities such as ions and oligomers to obtain a hydrogel of poly 2-(2-hydroxyethyl)thiophene. The freeze-dried powder of the gel was pressed into blocks, and its electrical conductivity was 6.2 S·cm ^-1 as tested by the standard four-probe method.

B embodiment: interface reaction

Example 1: Interfacial reaction generates phytic acid-doped polyaniline hydrogel

First prepare 20 ml of ammonium persulfate oxidant aqueous solution with a concentration of 2M, and add phytic acid. And configure 25ml of monomeric organic solution mixed with aniline and carbon tetrachloride. The ratio of the amount of substances is ammonium persulfate:aniline:phytic acid=3:6:1. The monomer organic solution is placed in a container, and then slowly poured into an aqueous solution of an oxidant to form a separated water-carbon tetrachloride two-phase solution. Within minutes, polymerization occurs at the interface of aqueous and organic solutions. A hydrogel of polyaniline is formed in the aqueous phase. It can be observed that the aqueous solution turns dark green and loses fluidity to form a gel. Finally, the organic phase solution was removed, and the hydrogel was dialyzed in deionized water to purify the hydrogel to remove impurities such as ions and oligomers. The freeze-dried powder of the gel was pressed into a block, and its electrical conductivity was 0.018S·cm ^-1 as tested by the standard four-probe method.

Example 2: Interfacial reaction generates phytic acid-doped polypyrrole hydrogel

First prepare 20 ml of ammonium persulfate oxidant aqueous solution with a concentration of 2M, and add phytic acid. And configuration pyrrole and carbon tetrachloride mixed monomer organic solution 25ml. The ratio of the amount of substances is ammonium persulfate:pyrrole:phytic acid=3:6:1. The monomer organic solution is placed in a container, and then slowly poured into an aqueous solution of an oxidant to form a separated water-carbon tetrachloride two-phase solution. While pouring, the polymerization reaction occurs rapidly at the interface of the aqueous solution and the organic solution. A hydrogel of polypyrrole is formed in the aqueous phase. It can be observed that the aqueous phase solution turns black rapidly and loses fluidity to form a gel. Finally, the organic phase solution was removed, and the hydrogel was dialyzed in deionized water to purify the hydrogel to remove impurities such as ions and oligomers. The freeze-dried powder of the gel was pressed into blocks, and its electrical conductivity was 1.8 S·cm ^-1 as tested by the standard four-probe method.

Example 3: Interfacial reaction generates phosphoric acid-doped polypyrrole hydrogel

First prepare 20 ml of ammonium persulfate oxidant aqueous solution with a concentration of 2M, and add phosphoric acid. And configuration pyrrole and carbon tetrachloride mixed monomer organic solution 25ml. The ratio of the amount of substances is ammonium persulfate:pyrrole:phosphoric acid=1:2:2. The monomer organic solution is placed in a container, and then slowly poured into an aqueous solution of an oxidant to form a separated water-carbon tetrachloride two-phase solution. While pouring, the polymerization reaction occurs rapidly at the interface of the aqueous solution and the organic solution. A hydrogel of polypyrrole is formed in the aqueous phase. It can be observed that the aqueous phase solution turns black rapidly and loses fluidity. After the reaction, the organic phase solution was discarded, and the hydrogel was dialyzed in deionized water to purify the hydrogel. The freeze-dried powder of the gel was pressed into blocks, and its electrical conductivity was 2.1 S·cm ^-1 as tested by the standard four-probe method.

Example 4: Interfacial reaction to generate polyvinylphosphoric acid doped polypyrrole hydrogel

First prepare 20 ml of ammonium persulfate oxidant aqueous solution with a concentration of 2M, and add polyvinyl phosphoric acid. And configuration pyrrole and carbon tetrachloride mixed monomer organic solution 25ml. The ratio of the amount of substances is ammonium persulfate:aniline:the amount of phosphoric acid groups in polyvinyl phosphoric acid=1:2:2. The monomer organic solution is placed in a container, and then slowly poured into an aqueous solution of an oxidant to form a separated water-carbon tetrachloride two-phase solution. Within seconds, polymerization occurs at the interface of aqueous and organic solutions. A hydrogel of polypyrrole is formed in the aqueous phase. It can be observed that the aqueous phase solution turns black rapidly and loses fluidity. After the reaction, the organic phase solution was discarded, and the hydrogel was dialyzed in deionized water and ethanol to purify the hydrogel. The freeze-dried powder of the gel was pressed into blocks, and its electrical conductivity was 2.5 S·cm ^-1 as tested by the standard four-probe method. The obtained hydrogel has good biocompatibility, as shown in FIG. 7, which is a fluorescence microscope image of bovine bone marrow stem cells grown on polyvinyl phosphate-doped polypyrrole hydrogel.

In conclusion, the present invention provides a method for forming pure conductive polymer hydrogels (not composite materials) whose host is a monolithic coral-like conductive polymer nanostructure. The synthesis of conductive polymer hydrogels and monolithic porous nanostructures is easy to mass-produce, can be carried out at room temperature, and the synthesis process does not produce pollution and is very green. Because the synthesized conductive polymer hydrogel has the advantages of pure conductive polymer directly forming a hydrogel host material, high ion conductivity, superhydrophilicity, and high biocompatibility, the method and material of the invention can be widely used Applied to devices based on conductive polymer hydrogels and their nanostructures, such as biosensors, chemical sensors, transistors, memories, supercapacitors, lithium batteries, fuel cells, biofuel cells, artificial muscles, artificial organs, drug release, electromagnetic Shielding, anti-corrosion decorative coating, etc. In this method, the conductive polymer in the solution is cross-linked into a whole by doping and cross-linking the molecular chains of the conductive polymer with multi-component doping acid to form a monolithic coral-like nanostructure. The reaction can be carried out in two schemes: aqueous solution homogeneous reaction or water-organic solvent two-phase interfacial reaction. Different conductive polymer hydrogels can be obtained by choosing various monomers, solvents, oxidants, and multi-component doping acids.

Example C: Phytic acid-doped polyaniline hydrogel glucose oxidase electrode

According to the formula in Example 1 of A, mix the precursor solution and drop it on the surface of the platinum electrode, exchange it with deionized water to remove impurity ions after forming a hydrogel, add glucose oxidase dropwise after drying, and combine the electrode with the calomel electrode etc. constitute a 3-electrode system. Add glucose aqueous solution to the solution gradually, forming a glucose increment of 1mmol/L every drop. It can be seen from Figure 10 that the hydrogel enzyme electrode is very sensitive to glucose sensing, with a response time of 6 s, while the usual enzyme electrode made of polyaniline is usually on the order of several minutes.

Claims (12)

1. the compound method of a conductive polymers; It is characterized in that; As doping agent and linking agent, make monomer with polyprotonic acid under the oxygenant effect, obtain the conductive polymers hydrogel through chemical oxidising polymerisation; Said monomer is at least a in pyrroles's or derivatives thereof, thiophene or derivatives thereof, the aniline or derivatives thereof; The acid groups of said polyprotonic acid comprises phosphate or polyprotonic acid is the polyprotonic acid that per molecule contains molecular weight≤800 that are selected from acid groups at least a among sulfonic group, nitroxyl or the carboxylic acid group more than 2, and aforementioned polyprotonic acid is phytic acid, polyvinyl phosphoric acid, N-sulfonic acid butyl-3-Methylimidazole hydrosulfate, N-sulfonic acid butyl-pyridinium hydrosulfate or 1,2; 4, at least a among the 5-benzene tertacarbonic acid.

2. the compound method of conductive polymers as claimed in claim 1 is characterized in that the mole number of the acid groups that polyprotonic acid comprises and the monomeric mol ratio of conductive polymers are 1:12 ~ 12:1.

3. the compound method of conductive polymers as claimed in claim 1 is characterized in that the mole number of the acid groups that polyprotonic acid comprises and the monomeric mol ratio of conductive polymers are 2:1 ~ 1:2.

4. the compound method of conductive polymers as claimed in claim 1 is characterized in that said polyprotonic acid is a phytic acid.

5. like the compound method of claim 1 or 2 each described conductive polymerss, the water cut that it is characterized in that said conductive polymers hydrogel is 30%-85%.

6. the compound method of conductive polymers as claimed in claim 5, the water cut that it is characterized in that said conductive polymers hydrogel is 34%-85%.

7. according to claim 1 or claim 2 the compound method of conductive polymers is characterized in that oxygenant is at least a in persulphate, iron(ic)chloride, cupric chloride, Silver Nitrate, hydrogen peroxide, hydrochloro-auric acid or the ceric ammonium nitrate.

8. according to claim 1 or claim 2 the compound method of conductive polymers is characterized in that may further comprise the steps:

(1) preparation comprises first solution of oxygenant;

(2) preparation comprises monomeric second solution;

(3) first solution is mixed with second solution, make monomer polymerization obtain the conductive polymers hydrogel;

Wherein, in step (1) and (2), first solution is the aqueous solution, and second solution is the aqueous solution or organic solution, and polyprotonic acid is formulated in first solution and/or second solution.

9. according to claim 1 or claim 2 the compound method of conductive polymers, it is characterized in that further comprising the steps of: the resulting conductive polymers hydrogel of purifying after drying obtains the porous nanometer structure conductive polymers.

10. the conductive polymers of each said compound method gained among the claim 1-9.

11. an electroactive electrode, the conductive polymers of each said compound method gained among the surface coverage claim 1-9.

12. the preparation method of the described electroactive electrode of claim 11 may further comprise the steps:

(I) preparation comprises first solution of oxygenant;

(II) preparation comprises monomeric second solution;

(III) first solution is mixed with second solution;

The method of (IV) use spin coating, dipping, casting, spray ink Printing or silk screen printing, the mixing solutions that in electrode holder surface coverage step (III), obtains, reaction generates conductive polymers hydrogel electrode structure;

Wherein, in step (I) and (II), first solution is the aqueous solution, and second solution is the aqueous solution or organic solution, and polyprotonic acid is formulated in first solution and/or second solution.

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