JPH082944B2 - Novel semiconductive or conductive polymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a novel conductive or semiconductive polymer.

2. Description of the Related Art In recent years, electronic materials have been extensively researched, and among them, functional polymer materials using conjugated polymers have attracted attention as having various possibilities. It is known that when a conjugated polymer is doped with an impurity, a complex is usually formed, and an insulator or a semiconductor has an electric conductivity comparable to that of a metal, and its conduction mechanism has not been clarified yet. However, it is expected as a functional material and various materials have been studied.

Polymers that have been conventionally studied include polyparaphenylene-based, polythiophene-based, polypyrrole-based, and polyacetylene-based (JP-A-61-4165, JP-A-56-136469, Jo
urnal of Polymer Sciense, Polymer Chemical Editio
n, Vol. 12, pages 11 to 20), but none of them have yet to have sufficient characteristics. Moreover, almost no polyin polymer still exists.

In addition, a polyaromatic vinylene compound represented by the following general formula (II) has also been reported.
61-4165 discloses polyphenylene vinylene, and JP-A 61-148231 discloses polythienylene vinylene and polyfuranylene vinylene, and their properties have been reported.

_{Ar-CH = CH n ... (} II) (Ar is a group having a conjugated system) These aromatic vinylene compound is capable of doping impurities as well as other conjugated compounds, gas doping such SO ₃ Alternatively, it has been found that both n-type and p-type doping can be performed by doping electrolyte ions by an electrochemical method, and various applications are expected as new electronic materials.

In addition to the above polyene compounds, conjugated polyyne compounds such as polydiacetylene have also been synthesized as functional polymer materials mainly by solid phase polymerization method and LB film method (Langmuir-Blodgett method). . However,
No report has been made on an organic polymer compound containing a polyyne in which an aromatic unit such as a phenylene group and a -C≡C- group are alternately bonded in the main chain.

OBJECT OF THE INVENTION The present invention provides a novel organic conductive or semiconductive polymer.

Structure of the Invention The novel semiconductive or conductive polymer of the present invention is characterized by having a repeating unit represented by the following general formula (I) in the main chain.

Ar-C ₌ Cn ... (I) (In formula, Ar shows the following.

Ar: a group having a conjugated system such as a linear aromatic compound or a condensed ring aromatic compound) Hereinafter, the present invention will be described in more detail.

Examples of Ar in the general formula (I) include groups having a conjugated system such as a linear aromatic compound and a condensed ring aromatic compound.

As the linear aromatic compound group, Is exemplified.

Further, as the condensed ring aromatic compound group, Is exemplified.

The degree of polymerization n is not particularly limited, but 10 or more is suitable as a semiconductor, which is an insoluble and infusible polymer.

The polymer of the present invention can be obtained as a stable film having excellent film-forming properties, and is electrochemically active and can reversibly stabilize the dopant in the polymer. In addition, a part or all of the polyyne compound is crystalline, and its electric conductivity is changed by doping. For example, ^10-9 (S / c
It can be changed from m) to 10 ² orders. In particular, the behavior of the polyyne compound film formed on the copper electrode shows a color change from yellow to black at a potential of −2.0 V or less with respect to the silver electrode. Further, the natural electrode in this state shows about -0.9 V, and this color change is reversible with respect to potential scanning.

The polymer of the present invention has electric conductivity as a semiconductor or a conductor, and since the light absorption characteristics are reversibly changed by doping / dedoping of a dopant, the electrode activity of a battery, particularly a secondary battery is It can be used for materials, electrode materials, electromagnetic shield materials, electrochromic materials, PN junction devices and the like.

The high molecular polymer of the present invention has, for example, the following general formula (II)
It can be obtained by reducing the monomer represented by

Z ¹ -Ar-Z ² (II) (In the formula, each symbol indicates the following.

Ar: same as in general formula (I) Z ¹ , Z ² : trihalogenated methyl group) Z ² of Z ¹ is, for example, a trihalogenated methyl group.
CCl _3, -CBr _3, and the like.

By reducing and polymerizing this monomer, particularly by electrochemically reducing it, a semiconductive or conductive polymer can be obtained.

This electrochemical method is generally described, for example, in J. Electroc.
hem.soc., Vol.130, No.7, 1506 ~ 1509 (1983), Electroc
hem. Acta., Vol. 27, No. 1, 61-65 (1982), J. Chem. Soc.,
Chem. Commun., 1199- (1984), etc.
In the present invention, the polymerization reaction proceeds by the elimination of the reducing group simultaneously with the reduction of the monomer. The present invention is realized by putting a solution obtained by dissolving a monomer and an electrolyte in a solvent into a predetermined electrolytic cell, immersing the electrode, and applying an electric field, so that the polymer is formed on the surface of the cathode as a film or fibrous material. Is obtained as The film thickness can be controlled by the amount of electricity supplied.

As the electrolyte salt, tetramethylammonium perchlorate, tetraethylammonium perchlorate, tetrabutylammonium perchlorate, tetramethylammonium tetrafluoroborate, tetraethylammonium tetrafluoroborate, tetrabutylammonium tetrafluoroborate, perchlorine Lithium acid, lithium tetrafluoroborate, tetramethylammonium hexafluoroarsenate, tetraethylammonium hexafluoroarsenate,
Hexafluoroarsenic acid tetrabutylammonium, sodium hexafluoroarsenate, hexafluorophosphate tetramethylammonium, hexafluorophosphate tetrabutylammonium, sodium hexafluorophosphate, sulfuric acid, tetramethylammonium hydrogensulfate, tetrabutylammonium hydrogensulfate, Examples thereof include sodium trifluoroacetate, tetramethylammonium p-toluenesulfonate, and tetrabutylammonium p-toluenesulfonate. In particular, good results are obtained when tetrabutylammonium salt is used as the cation and boron tetrafluoride or phosphorus hexafluoride is used as the anion.

As the solvent, it is preferable to use a polar solvent that has been subjected to purification treatment such as dehydration and degassing, and tetrahydrofuran, hexamethylphosphoramide, dimethoxyethane,
Acetonitrile, propylene carbonate, nitrobenzene, benzonitrile, methylene chloride, dimethylformamide,
Dimethyl sulfoxide or the like is used, and particularly preferably, tetrahydrofuran, dimethoxyethane, or propylene carbonate.

Copper as the electrode material that constitutes the electrode during electrolytic polymerization,
A metal electrode of silver, gold, platinum, nickel, zinc, tin, aluminum or the like: a carbon electrode of glassy carbon or the like; a metal oxide electrode of ITO or the like can be used, and a copper or platinum electrode is particularly preferable. The reaction atmosphere is preferably performed under an inert atmosphere such as nitrogen or argon.

The electrolysis method proceeds using any of the constant current electrolysis method, the constant potential electrolysis method, and the constant voltage electrolysis method, but the constant potential electrolysis method is preferable, and for the standard electrode of Ag / Ag ⁺ , − 1V or less,
It is preferable to apply a potential of −2 V to −10 V to the working electrode.

Depending on the electrolytic polymerization conditions, the following double bond unit may be included in the main chain.

(In the formula, each symbol indicates the following.

Ar; the same X ¹ and X ^{2 in the} general formula (I): halogen atom) For example, even when the same monomer is used, when tetrahydrofuran is used as a solvent during electrolytic polymerization, the general formula (II
The units shown in I) are relatively abundant in the main chain, while
By using propylene carbonate as the solvent, the polyyne unit represented by (I) will occupy most of the main chain.

Effects of the Invention The polymer of the present invention shows semiconductivity or conductivity by doping, and is useful as a functional polymer material.

Example 1 In an electrolytic cell using copper for the anode and the anode, If, [(n-Bu) ₄ N] ⁺ · ClO ₄ ^- (0.1 mol) (Bu: butyl group)
A solution prepared by dissolving and in propylene carbonate was added. Next, potentiostatic electrolysis was performed at −2 V vs Ag / Ag ⁺ in an argon atmosphere to prepare a polymer having a polyyne unit containing a triple bond as a main skeleton. The analytical values and measured values of the obtained film are shown in Table 1 below together with Examples 2 to 4 below.

Example 2 A polymer film having a polyyne unit containing a triple bond as a main skeleton was prepared in the same manner as in Example 1 except that platinum was used as the anode and the anode and potentiostatic electrolysis was performed at −5 V vs Ag / Ag ⁺ . .

Example 3 In an electrolytic cell using copper for the anode and the anode, If, [(n-Bu) ₄ N] ⁺ · BF ₄ ^- was placed a solution obtained by dissolving the (0.1 mole) in propylene carbonate. Next, potentiostatic electrolysis was carried out at −2 V vs Ag / Ag ⁺ in an argon atmosphere to prepare a polymer having a polyyne unit containing a triple bond as a main skeleton.

The Raman spectrum and IR spectrum of this polymer are shown in FIG. 1 and FIG. 2, respectively.

Example 4 Platinum was used as the electrode and the monomer was used. Was used, and a polymer film was prepared in the same manner as in Example 1 except that tetrahydrofuran was used as the solvent instead of propylene carbonate. This polymer film has a smaller triple bond content than in Examples 1 to 3.

Example of application Using the polymer material of the present invention, an organic secondary battery having the structure shown in Fig. 3 was prepared.

As the positive electrode active material 11 and the negative electrode active material 13, the polymer film of Example 1 was pressure-bonded to Ni foils (current collectors) 15 and 15, respectively, to obtain a positive electrode and a negative electrode. Polypropylene nonwoven fabric is used as the separator 17, L ₁ BF ₄ (1 mol) / propylene carbonate is used as the electrolytic solution, and ₁ is used as the exterior films 19 and 19.
20μm biaxially oriented polyester film and sealing material
Toray Chemistat R99 was used as 21, and the thin sheet battery shown in FIG. 3 was prepared.

The outer electrodes were obtained by spot welding Ni wires to the Ni foil collectors 15 and 15.

 The evaluation results of this battery are as follows.

 Open voltage: 1.4 V Theoretical energy density: 64 Wh / kg Each evaluation was performed as follows.

(1) Open circuit voltage: The terminal voltage between both electrodes was measured after charging and discharging for 10 minutes.

(2) Logical energy density: Measured by charging and discharging with a constant current (0.3 mA).

[Brief description of drawings]

FIG. 1 is a graph showing the Raman spectrum of the polymer obtained in Example 3 of the present invention. FIG. 2 is a graph showing the IR spectrum of the polymer obtained in Example 3 of the present invention. FIG. 3 is a sectional view showing a constitutional example of a secondary battery using the polymer of the present invention as an electrode active material.

 ─────────────────────────────────────────────────── --- Continuation of the front page (72) Inventor Hiroshi Nishihara 4-13-3 Gotanda, Shinagawa-ku, Tokyo 303 Heights 303 (72) Inventor Kunitsu Aramaki 2-23-26 Okusawa, Setagaya-ku, Tokyo (56) Reference Documents JP-A-63-125520 (JP, A) JP-A-63-225622 (JP, A)

Claims (1)

[Claims] 1. General formula (I) Ar—C≡C _n ... (I) (wherein Ar represents the following: Ar: Conjugation of linear aromatic compound, condensed ring aromatic compound, etc. A novel semiconducting or conductive polymer having a main skeleton of a repeating unit represented by a group having a system.