JPH0618909B2 - Manufacturing method of composite materials - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a composite material. More specifically, the present invention relates to a method for producing a composite material by polymerizing an electrochemically polymerizable monomer into a polymer material by an electroless oxidation polymerization method.

[Prior Art] As a conventional method for producing a composite material, there is an electrolytic oxidative polymerization method. (Osamu Niwa, Toshiaki Tamamura et al., Proceedings of the Polymer Society of Japan 33
4844-845) This is a method for electrochemically polymerizing pyrrole in the insulating film to obtain a conductive composite film for the purpose of making the insulating film conductive. This method is a method in which an insulating film is formed on a substance that can serve as an electrode by a casting method, or the formed insulating film is brought into close contact with the electrode, and electrolytic polymerization is performed in an electrolytic cell.

[Problems to be Solved by the Invention] However, this method has drawbacks such as the need for a device for electrolytic oxidation polymerization such as electrodes and the troublesome operation. Further, in this method, depending on the combination of the polymer material to be composited and the electrochemically polymerizable monomer, a polymer is not produced, or even if produced, only a heterogeneous composite material is obtained. There was also a problem.

An object of the present invention is to solve these problems and provide a method for producing a composite material which is industrially easy without requiring a troublesome operation.

[Means for Solving the Problems] The above object is achieved by the present invention described below.

That is, the present invention, a polymer material selected from a film, an ion exchange membrane and a solid polymer electrolyte is brought into contact with a solution containing an oxidant, the solvent in the solution is removed, and then electrochemically It is a method for producing a composite material, which comprises contacting with a monomer capable of oxidative polymerization.

The monomer that can be electrochemically polymerized is hereinafter simply referred to as a monomer.

The monomer of the present invention may be not only a so-called monomer but also an oligomer such as a dimer or trimer, as long as it can be electrochemically polymerized. Such a monomer is roughly classified into a hetero five-membered ring, a compound structurally containing it and derivatives thereof, a compound having an amino group, a hydroxyl group or an alkoxy group on a benzene ring, and other compounds. For example, a hetero five-membered ring and a compound structurally containing it include pyrrole, furan, thiophene, N-methylpyrrole, 3-methylthiophene, indole, carbazole, benzofuran,
Compounds having an amino group, a hydroxyl group or an alkoxy group on the benzene ring such as benzothiophene are aniline, m-diaminobenzene, p-methylaniline, p-methoxyaniline, 3,5-dimethylaniline, phenol, 3,5
-Dimethylphenol, m-methylphenol, 2,6
-Dimethylphenol, anisole, phenetole,
o, m, p-methylanisole, o, m, p-dimethoxybenzene, etc., and other compounds include azulene,
Examples include pyridazine and dibenzocrown ethers.
These monomers may be used as they are, or may be diluted with an appropriate solvent before use. Further, when the monomer is a liquid, its vapor may be used.

In the present invention, a polymer material selected from an ordinary film, an ion exchange membrane and a polymer solid electrolyte is used. For example, typical films include polystyrene, vinyl chloride-based polymers, phenolic resins, PMMA, polyethylene, polyvinylcarbazole, polyimide, polyamide, polyester and the like. "Nafion" for the ion exchange membrane
(Manufactured by du Pont), "Selemion" (Asahi Glass Co., Ltd.)
Manufactured by Tokuyama Soda Co., Ltd., and other polymer solid electrolytes include polyethylene glycol.

As the oxidant, an oxidant of a redox compound whose electrochemical equilibrium potential is higher than the oxidative polymerization initiation potential under the polymerization conditions of the monomer to be polymerized is used. As such an oxidizing agent, a high valence transition metal compound, halogen, a halogen compound, a peracid, or a salt thereof is used. The high valence transition metal compound is a compound of a transition metal having a valence of 2 or more, such as cupric chloride, ferric chloride, stannic chloride,
Chlorides such as molybdenum chloride and tungsten chloride, or other corresponding halides, sulfates such as copper sulfate and ferric sulfate, ferric nitrate, sulfates such as copper nitrate, manganese dioxide, lead dioxide, etc. And oxo acids such as permanganate and potassium ferricyanide. For halogen, iodine, bromine, etc. are used. The halogen compound is a compound in which a halogen atom easily has a valence of +1, and examples thereof include N-bromosuccinimide, N-acetamide, and cyanuric chloride. Examples of peracids and salts thereof include ammonium persulfate,
Peracetic acid or the like is used. These oxidizing agents may be used alone or in combination of two or more.

When using an oxidizing agent that does not exhibit a sufficient effect, it is effective to assist oxygen in the air or hydrogen peroxide solution, or to use a cocatalyst. Cobalt (II) acetate, cobalt (II) benzoate, cobalt (II) acetylacetonate, etc. are effective as such an oxidation co-catalyst. Depending on the reaction, an acid (including Lewis acid) ) Is effective. As the Lewis acid, anhydrous aluminum chloride, anhydrous ferric chloride, anhydrous titanium chloride, anhydrous stannic chloride or the like is used.

Next, a method for manufacturing the composite material of the present invention will be described. In the method of the present invention, a polymeric material is contacted with a solution containing an oxidizing agent, the solvent in the solution is removed, and then a monomer capable of being electrochemically oxidatively polymerized is contacted.

The solvent used in the above method is preferably one that does not dissolve the polymer material and penetrates into the polymer material. For example, polysulfone, alcohols, polyimide, P
MMA, polystyrene, vinyl chloride polymers, polar solvents such as acetonitrile for phenol resins, and benzene, xylene, hexane, chloroform, heptane, 1.2-dichloroethane for silicone resins are preferable. When using a polymer material having microporosity,
It is preferable to use a solvent whose microporosity does not collapse. The solvent of the monomer and the solvent of the oxidizing agent may be the same kind or different kinds, but the same kind is preferable. The content of the monomer or the oxidizing agent in the solution can be appropriately changed depending on the number of contact operations.

Further, the content of the polymer to be composited in the polymer material can be arbitrarily changed according to the purpose of use of the composite material by changing the amount of the oxidizing agent to be impregnated and the number of reactions.

After the contact reaction, the oxidizing agent remaining in the polymer material or the reacted oxidizing agent is preferably removed by washing with a solvent.

The produced composite film is a conductive film when the monomer is, for example, pyrrole. Therefore, the method of the present invention can be used by using pyrrole to make the insulating film such as polyimide or polyester conductive.
A composite film having a conductivity of about 0 ^{-1 to 1} scm ^-1 is obtained. A durable battery active material film can be produced by combining a monomer that can be a battery active material and a film having high mechanical strength.

[Effects of the Invention] As described above, according to the method of the present invention, a composite material can be easily manufactured. Further, unlike the electrolytic oxidation polymerization method, the method of the present invention can be easily continuous.

Furthermore, the composite material obtained by the method of the present invention has various uses because it becomes a film having various properties by combining a monomer and a film. Furthermore, it is possible to obtain a polymer material in which an oxidized polymer of a monomer is uniformly contained.

Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1 An example of an experiment using polyimide as a film will be shown. An acetonitrile solution containing pyrrole (about 0.5 M) was designated as solution C, and an acetonitrile solution containing anhydrous ferric chloride (about 0.15 M) was designated as solution D. A 7.5 μm thick “Kapton” (made by du Pont) film was evenly wetted with the solution D and then left for about 10 minutes. Then it was dried with a dryer. The film was similarly wetted with Solution C and dried. The above operation was repeated 5 to 6 times to generate polypyrrole in the polyimide film, and the film was thoroughly washed with pure water to remove the iron compound in the film. The resistance in the thickness direction of this composite film is 10 ³ as measured by a tester.
It was -10 ⁴ Ω. The electrical conductivity was 10 ^{-1 to 1} scm ^{-1 as} determined from the relationship between current and voltage by applying a direct current to the film.

125 μm thick polyimide film (“Kapton”)
Table 1 shows the relationship between the weight percentage of the polymer and the resistance when a composite film was prepared by the same operation using a 100 μm thick polyester film (“Lumirror”: manufactured by Toray Industries, Inc.). Further, FIG. 1 shows the relationship between the number of operations (solution D treatment → drying → solution C treatment → drying) of the polyamide composite film and the resistance value measured by a tester.

Example 2 A PMMA solution in which four types of anhydrous ferric chloride having different weights were dissolved or dispersed (0.5 g of PMMA powder dissolved in 4.5 g of methyl acetate cellosolve solution) was cast by a glass plate ( 5 × 5 cm ² ) to prepare a PMMA film containing ferric chloride. This film is 1
It was dried at 10 ° C to 120 ° C for 2 hours. At this time, the color of the film was yellow. This was put in a petri dish containing pyrrole (several cc) without touching the pyrrole solution, and the lid was covered. When left as it is for 4 hours, the pyrrole vapor and ferric chloride reacted to generate polypyrrole in the PMMA film. After that, it was thoroughly washed with methanol and ion-exchanged water. The relationship between the resistance of this composite film and the weight percentage of the oxidation catalyst is shown in Table 2. The thickness of this film was about 0.75 μm, and the color was between transparent gray and black, and became darker with the amount of the oxidation catalyst. In addition, in all the composite films, the generation state of the polymer was uniform.

Example 3 Polyvinyl chloride powder (3 g) and anhydrous ferric chloride (0.7 g) were dissolved in tetrahydrofuran (30 cc). This was applied onto a glass plate (5 × 5 cm ² ) by a casting method to form a film having a thickness of 1.25 μm, and then dried at about 60 ° C. for 30 minutes. This film was contacted with pyrrole vapor for 3 hours as in Example 2. Then, it was thoroughly washed with methanol and ion-exchanged water. The IR measurement of the film thus made was performed. The results are shown in FIG.

The color of the produced composite film was transparent black, and the production state of the polymer was uniform.

Example 4 Solution E was a solution prepared by dissolving 1 g of polyvinyl chloride powder and 1 g of anhydrous ferric chloride in 30 cc of tetra and drofuran.
Solution F was a solution prepared by dissolving 1 g of polyvinyl chloride powder and 2 g of anhydrous ferric chloride in 30 cc of tetrahydrofuran. Films having thicknesses of 1.25 μm and 0.5 μm were prepared from these solutions. These films were contacted with pyrrole vapor for 3 hours in the same manner as in Example 2, and then thoroughly washed with methanol and ion-exchanged water. The resistance values of the composite film thus obtained are shown in Table 3.

The color of the produced composite film was all black, and the production conditions of the polymer were all uniform.

Comparative Example 1 A composite film was prepared in the same manner as in Example 1 except that the steps of drying the solution D and the solution C were omitted. The production state of the polymer was not uniform.

[Brief description of drawings]

FIG. 1 shows the relationship between the number of operations and the resistance value when producing the polyamide composite film of Example 3, and FIG. 2 shows the IR chart of the polyvinyl chloride composite film obtained in Example 6. .

Claims (1)

[Claims] 1. A polymer material selected from a film, an ion exchange membrane and a polymer solid electrolyte is brought into contact with a solution containing an oxidant, the solvent in the solution is removed, and then electrochemically. A method for producing a composite material, which comprises contacting with a monomer capable of oxidative polymerization.