JPS62133604A - Conductive polymer composite and manufacture of the same - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applicable to batteries, electrodes,
Conductive polymer composites useful as electrochromic display elements and electrolytes for solid capacitors Conventional technology In recent years, electrical and electronic devices have made remarkable progress in becoming lighter, thinner, and smaller, and the various elements used in them have also Not only is there an urgent need for weight reduction, thinness, and size reduction, but there are also strong expectations for the emergence of new and better materials. New conductive polymers are being actively developed to meet these demands or expectations. For example, polyacetylene exhibits a high electrical conductivity of 102 to 103 S/crn by doping with iodine or arsenic pentafluoride [for example, Synthetic Metals Vol. 1, No. 2, p. 101]. (1979/1980)] is being considered not only as an electrode material for secondary batteries due to its excellent charge/discharge characteristics, but also as a solar cell material because its light absorption characteristics are similar to those of sunlight. It is being considered.

However, polyacetylene itself is easily oxidized and is susceptible to moisture in its doped state. Not only has it been studied, but since it causes reversible discoloration when electrochemically oxidized or reduced, it is also being considered as an element for display or recording materials as an electrochromic material. M. Drouy et al., Journal de Physique, Vol. 44,
No. 6, pp. C5-595 (1983) (A, M, D
ruy + et al-+ J, de Physi
que + 44 (6) +C5-595 (1983)
reference〕.

When trying to make the shape thinner or smaller using these conductive polymers, there are two methods: depositing the polymer directly onto the electrode substrate using an electrochemical polymerization method, and obtaining the polymer using a chemical polymerization method, followed by molding. There are many ways to do this. Obtaining polymers electrochemically has the advantage that thin films can be easily obtained, but the resulting polymers are often fragile and can only be handled under special polymerization conditions. A thin film with strength cannot be obtained.

In order to overcome this drawback, for example, Dozai et al. performed electrochemical polymerization of virole using an electrode substrate coated with a thin polymer film having mechanical strength. Proposed polymer composites [Journal of Chemical Society Chemical Communication, J-Chem, So
c, + Chem-Commun.) Vol. 1984, p. 817].

Problems to be Solved by the Invention An object of the present invention is to overcome the drawbacks of the conventional conductive polymers and provide a conductive polymer composite having excellent mechanical strength and flexibility, and a method for producing the same. There is a particular thing.

Means for Solving the Problems The present invention provides a conductive polymer composite and a method for producing the same that can achieve the above objects.

That is, the present invention relates to a conductive polymer composite characterized by comprising an electrochemically inactive thermoplastic polymer thin film and an electrochemically polymerized polymer having an isothianaphthene structure.

In addition, the present invention involves forming a thin film of an electrochemically inert thermoplastic polymer on an electrode substrate, and then electrochemically polymerizing a monomer having an isothianaphthene structure using the substrate as a working electrode. , relates to a method for producing a conductive polymer composite, which comprises forming a polymer film having an isothianaphthene structure on the substrate.

Hereinafter, the conductive polymer composite of the present invention and its manufacturing method will be explained.

In the conductive polymer composite of the present invention, an electrode substrate is coated with a thin film of an electrochemically inactive thermoplastic polymer, and R1 and R2 in the general formula C are each independently represents hydrogen or a hydrocarbon group having 1 to 5 carbon atoms; 5 representing degree
500) by electrochemically forming a polymer having an isothianaphthene structure.

The conductive polymer composite thus obtained is a composite of an electrochemically inactive thermoplastic polymer thin film and a polymer having an isothianaphthene structure.

The conductive polymer composite referred to in the present invention refers to a composite in which a polymer having an isothianaphthene structure is dispersed inside an electrochemically inert thermoplastic polymer thin film depending on the molding conditions, or isothianaphthene. It refers to a two-layer structure in which a structured polymer is laminated onto an electrochemically inert thermoplastic polymer.

The thermoplastic polymer used as the Sakaki cover material for a certain layer of Raikai is a polymer that dissolves and undergoes a deterioration reaction in organic solvents or electrolytes used when electrochemically polymerizing monomers with an isothianaphthene structure. It is sufficient to select a material that does not cause such problems, and in particular, it swells to some extent in the electrolytic solution, and the monomer molecules having an isothianaphthene structure diffuse into the thermoplastic polymer thin film, causing electricity to flow on the surface of the electrode substrate. Those that allow chemical polymerization reactions to proceed are preferred. Typical examples of such thermoplastic polymers include polyvinylidene fluoride, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinyl chloride, polyvinylidene chloride, polystyrene,
polymethyl methacrylate, polyvinyl alcohol, ethylene-vinyl acetate copolymer or its partial hydrolyzate,
Examples include styrene-butadiene copolymer.

A conventional method such as a dipping method, a spin coating method, a film pressure bonding method, etc. can be used to form a thin film of thermoplastic polymer on the electric rod substrate.

The thickness of the thermoplastic polymer thin film is preferably within the range of 0.1 to 1000 μm.

A method for electrochemically polymerizing a monomer having an isothianaphthene structure is as described in Japanese Patent Application No. 109329/1984, for example, by coating an electrode substrate coated with a thin film of a thermoplastic polymer with an organic solvent. This is carried out by placing a counter electrode together with a solution in which a monomer having an isothianaphthene structure and an electrolyte are dissolved, and passing an electric current between the two electrodes.

Examples of the organic solvent include acetonitrile, benzonitrile, propionitrile, dioxane, tetrahydrofuran, sulfolane, propylene cargenate, and the like. In addition, as electrolytes, (i) pr6-, 5b
halide anions of elements of the Va group such as r6'', AsF6-, 5bCt6''', ll1a such as BF4-
halide anion of group element, I″″(I3-)
, halodane anions such as Br-+Ct-, C2O4
- and (ii) a perchlorate anion such as Li", N
a”, alkali metal ions such as K+, R4N+(
R can be a combination of a quaternary ammonium ion such as a hydrocarbon group having 1 to 20 carbon atoms, a phosphonium ion such as (C6H5)4P+, but is not necessarily limited to these. Specific examples of electrolytes consisting of the above combination include LiPF6,
LtSbF6゜LiAsF, NaI, NaA
F6+ NaAsF6+ NaAsF6゜(n-Bu)
aNBr, (n-Bu)aNCZ l (C6H5)
Examples include aPctr(C6H5)4PAsF6. These electrolytes may be used alone or as a mixture of two or more types if necessary, and when used, the electrolytes should be used at o, ooi to 100 mol/l, preferably from 0.01 to 5 mol/l.
It is used within the range of 0 mol/l. The concentration of electrolyte is o,
If the electrolyte concentration is less than ooi mol/1, the electrochemical reaction will not substantially proceed, and if the electrolyte concentration exceeds 100 mol/l, no effect of addition to increase the concentration will be observed.

The electrode substrate used in the present invention is not particularly limited as long as it does not deteriorate or corrode due to the electrolytic solution and electrolyte, and is usually made of metals such as platinum, gold, copper, nickel, inzium oxide, tin oxide, A transparent conductive material obtained by forming a thin film of gold or the like on a glass or polyester film by vacuum deposition or snobbing, or a carbon electrode material such as glassy carbon can be used.

The polymerization temperature cannot be determined unconditionally because various solvents can be used, but it is usually between -80°C and +200°C.
, preferably in the temperature range of -40°C to +100°C. The polymerization time varies depending on the type and concentration of the monomer having an isothianaphthene structure, the type and concentration of the electrolyte, and the desired ratio of the polymer having an isothianaphthene structure in the composite, so it cannot be generally specified. Not possible, but usually 0
．． 01 to 200 hours, preferably 0.1 to 100 hours is sufficient.

Effects of the Invention In addition to having the flexibility and strength of a thermoplastic polymer thin film, the conductive polymer composite of the present invention has stability in air and electromagnetic stability, which are characteristics of a polymer having an isothianaphthene structure. It exhibits chromism, high conductivity through doping, and high transparency during doping, making it extremely useful as a material for electrodes, electrochromic display elements, solid capacitors, etc. in the electrical and electronic industries.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but it goes without saying that the technical scope of the present invention is not limited by these Examples.

Example 1 An indium tin oxide glass plate having a surface resistance value of 15 Ω/hole was immersed in a 5-coil N,N-dimethylformamide solution of polyvinylidene fluoride (FORAFRON 100OVLD, PCUK, France) and then dried to form a 10 μm film. A thick polyvinylidene fluoride coated inzoum tin oxide glass plate was obtained. Using this material as a working electrode and a platinum plate as a counter electrode, the polymerization temperature was 30°C and 2.0°C in an acetonitrile solution with a concentration of 01 mol/l of isothianaphthene and 01 mol/l of n-tetrabutylammonium.
Electrochemical polymerization of isothianaphthenes was carried out by constant voltage method at an interelectrode potential of ˜2.5 V. After a polymerization time of 30 minutes, blue polyisothianaphthene was observed to be deposited on the electrode substrate coated with polyvinylidene fluoride. When the composite obtained by peeling from the electrode substrate was observed using a scanning electron microscope, it was found that the polyisothianaphthene was polymerized so that it was dispersed from the polyvinylidene fluoride electrode substrate side into the thin film. It was done. In the composite, the electrical conductivity at room temperature measured by the four-terminal method on the side where polyisothianaphthene was formed was 2.8 x 10-2 s/z, and the composite had toughness.

Comparative Example Polymerization was carried out in the same manner as in Example 1, using an indium tin oxide glass plate as a working electrode without applying an electrochemically inert thermoplastic polymer. When the obtained polymer was immersed in water, the film peeled off without losing its shape because the polymer lacked toughness.

Examples 2 to 5 Table 1 was prepared on the same indium tin oxide glass plate as in Example 1.
The electrochemically inert thermoplastic polymer shown in Table 1 was applied to a thickness of about 1 μm each as a working electrode, and a platinum plate was used as a counter electrode. Using a solution in which isothianaphthene and 0.2 mol of tetraphenylphosphonium chloride were dissolved, 2.
Electrochemical polymerization was carried out at 30°C for 30 minutes with an applied voltage of 0-2.5v. In both systems, blue polyisothianaphthene was precipitated, and a complex of polyinthianaphthene and an electrochemically inactive thermoplastic polymer was formed. All of the obtained composites had excellent toughness. Table 1 shows the measurement results of the drowsiness conductivity of the obtained composite.

Table 1 Reference Examples The composite of polyisothianaphthene and polyvinylidene fluoride obtained in Example 1 was electrochemically doped using a solution of 1.0 mole of lithium glycolate dissolved in acetonitrile. Its light transmittance was measured in the visible spectrum. Polyisothianaphthene changes from blue to colorless with doping, but in a composite. j
? Similarly, lysothianaphthene was shown to be colorless by doping, resulting in a transparent composite conductive thin film. The figure shows the visible spectra before and after doping, showing that doping results in an apparently transparent composite.

[Brief explanation of drawings]

The figure shows a composite composed of polyvinylidene fluoride and polyisothianaphthene obtained by electrochemically polymerizing a monomer having an isothianaphthene structure using an electrode coated with a thin film of polyvinylidene fluoride. This figure shows the changes in the visible spectrum when doping and doping are performed.

Claims (2)

[Claims] (1) A conductive polymer composite comprising an electrochemically inactive thermoplastic polymer thin film and an electrochemically polymerized polymer having an isothianaphthene structure. (2) A thin film of an electrochemically inert thermoplastic polymer is formed on an electrode substrate, and then a monomer having an isothianaphthene structure is electrochemically polymerized using the substrate as a working electrode. 1. A method for producing a conductive polymer composite, comprising forming a polymer film having an isothianaphthene structure thereon.