JPS5889640A - Conductive polyacetylene - Google Patents

Abstract

PURPOSE:To obtain titled polymer by carrying out a large amount of doping without the degradation of the original polymer, suitable for battery electrodes and the manufacturing of an n type polyacetylene, by the use of H2F<+> cation as a dopant. CONSTITUTION:The objective polymer can be obtained by electrochemically doping H2F<+> cation to the original polyacetylene. The original polyacetylene is preferably of one having fibrous microcrystalline structure. The doping amount of said H2F<+> cation is 1-40(pref. 2-30)mol% per mole of the recurring unit CH of the original polyacetylene. Preferable polyelectrolytes are of non-protonic and those with high dielectric constant, e.g., propylene carbonate, alpha-butyrolactone.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to acetylene polymers with high electrical conductivity.

Powdered acetylene polymers obtained by polymerizing acetylene using so-called Ziegler-Natsuta catalysts, which are composed of transition metal compounds and organometallic compounds, have electrical conductivity in the semiconductor region, making them suitable for electrical and electronic devices. It is already known that it is useful as a material. In addition, this powdered acetylene high polymer is BP, , BC1!3.
HCI! , C/2. SO2゜NO2, HCN, 02.
When treated with an electron-donating compound (acceptor) such as No, the electrical conductivity increases by up to 3 orders of magnitude, and conversely, when treated with an electron-donating compound (donor) such as ammonia or methylamine, the electrical conductivity decreases by up to 4 orders of magnitude. It is also already known that (D.J., Berets et al., Tr.
ansIIFarady Soc,.

64.823 (1968)).

Furthermore, it is already known that under certain polymerization conditions, a thin film of acetinine polymer having a fibrous microcrystalline (fibril) structure can be obtained (Japanese Patent Publication No. 32581/1983).
issue). In recent years, thin film acetylene polymers obtained by this method have been shown to have I2. C12°Br2. IC4IBr,
By chemically doping an electron-donating compound such as Li into an electron-accepting compound such as AsF5, SbF5, PF6, etc. or Na, the electrical conductivity of the acetylene polymer can be increased from 10-8 to 103 Ω-1 Crn. -1
It is already known that it can be freely controlled over a wide range of areas. (J, C.

S. Chem, Commu, 578 (1977)
, Phys, Rev. L-ett, , 39.1098
(1977), J. Am., Chem.

Soc, 100, 1013 (1978), J
, Chem, Ph9s6. Danyu, 5098 (1978)
).

Some of the present inventors have proposed a method for producing an acetylene polymer having a fibrous microcrystalline (fibril) structure by a method different from the above-mentioned method, and a method for molding the same (Japanese Unexamined Patent Publication No. 55-12
No. 8419, No. 55-129404, No. 55-142
No. 030, No. 55-145710, No. 55-1457
No. 11, No. 56-10428, No. 56-133133
No. 1) and a method for producing an acetylene polymer having high electrical conductivity by treating an acetylene polymer with a new dopant 1 (JP-A-55-129424, JP-A-55-129424)
No. 129425, No. 55-129426, No. 55-1
No. 29427, No. 55-143702, No. 55-14
3703) has already been proposed.

In addition to the above chemical doping method, electrochemical CIO: e pF'61 A8FM + A
Anion such as s F4- eCF3so; A manufacturing method has already been developed [J, COS, Chem, Com
mu,, 1979.594, C & EN Jan,
26, 39 (1981), J, C1S, Chem, Co.
mmu, 1981, 317).

However, when producing an n-type conductive acetylene polymer by doping HN electrochemically, the amount of dopant that can be doped into the acetylene polymer is at most 6 mols per mole of repeating unit CH of the acetylene polymer. It was morchi. When the amount of dopant exceeds 6 molty, a portion of the acetylene polymer deteriorates, resulting in a sharp drop in electrical conductivity. Increasing the amount of dopant that can be doped into the acetylene polymer is a significant improvement in the batch IJ-[C&ENJan,
26, 39 (1981), J.C.O.S., Che.
m, Commu.

, 1981.317'),
This is an essential requirement for producing acetylene high polymers with higher electrical conductivity, and among those in the industry, it is believed that the acetylene high polymers can be doped in a larger amount without degrading the acetylene high polymers, and the acetylene high polymers can be doped with n-type conductivity. There has been a strong desire to develop new dopants that provide polymers.

In view of the above points, the present inventors have discovered the present invention as a result of various studies on dopants that can be doped in larger amounts without deteriorating the acetylene polymer.

That is, the present invention relates to an electrically conductive acetylene polymer obtained by electrochemically doping an acetylene polymer with H2F cations.

+ The conductive acetylene polymer of the present invention can be doped in a large amount without deteriorating the acetylene polymer by using H2F cations as a dopant. It is ideal for batteries and as an n-type acetylene polymer with high electrical conductivity.

The acetylene polymer used in the present invention is not particularly limited and can be used in any form such as powder, film, or fiber, but it has a fibrous microcrystalline (fibril) structure. Acetylene polymers are preferred. A specific example of manufacturing acetylene high polymer is as follows:
For example, Special Publication No. 48-32581, J, Chem, Ph.
ys, 69(]), 106-111 (1978), and the method of JP-A-55-128419, JP-A-55-129404, and JP-A-55-129404, which some of the present inventors have already proposed.
No. 5-142030, No. 55-145710, No. 55
-145711, 56-10428, 56-1
Examples include methods such as No. 33133, but the method is not necessarily limited to acetylene polymers obtained by these methods.

The H2F cation used in the present invention is CF,
A known electrochemical method (
J, COS, Chem, Commu,, 1979,
594, J.

C.S. Chem, Commu, 1981, 31
7) However, it is not necessarily limited to these compounds, and the gist of the present invention is to dope the acetylene polymer with H2F cations.

The amount of H3P cation doped into the acetylene polymer is the repeating unit CH of the acetylene polymer.
1 to 40 mole per mole, preferably 2 to 30 mole
It's morchi. If the doping amount of H3P cation is less than 1 mol, it is not possible to produce an acetylene polymer with sufficiently high electrical conductivity, and if the doping amount exceeds 40 mol, the acetylene polymer will undergo oxidative deterioration. Undesirable.

A method for electrochemically doping an acetylene polymer with H2F cations is already known [J.

C.S. Chem, Commu, 1979.59
4.1 bid1. 1981.317, J. Elec.
troanal, Chem.

111.115 (1980)], but usually, the salt of the H3P cation of the present invention is dissolved as a supporting electrolyte in an aprotic and high dielectric constant organic solvent to form an electrolytic solution, and acetylene This can be done by applying a DC voltage of O, SV or higher so that the high polymer becomes the cathode. The amount of H3P cation doped can be freely controlled by measuring the amount of electricity flowing during electrolysis. Doping may be carried out either under constant current, constant voltage, or varying current and voltage conditions. The current value, voltage value, doping time, etc. during doping depend on the bulk density and area of the acetylene polymer used, the type of H2F cation salt, the type of electrolyte, and the required electricity of the conductive acetylene polymer. Since it varies depending on the conductivity, it cannot be defined unconditionally.

The electrolytic solution used in the present invention is usually a solution of the above H3P cation salt in a non-aqueous organic solvent. The organic solvent mentioned here is preferably one that is aprotic and has a high dielectric constant.

Specific examples include propylene carbonate), r-butyrolactone, dimethyl sulfoxide, dimethyl formamide, acetonitrile, ethylene carbonate, tetrahydro7rane, dimethoxyethane, methylformate, dichloroethane, etc. It is not limited. These organic solvents may be used alone or as a mixed solvent of two or more. The concentration of the electrolyte cannot be unconditionally defined because it varies depending on the type of positive or negative electrode used, doping conditions, operating temperature, type of electrolyte, type of organic solvent, etc., but it is usually in the range of 0001 to 10 mol/l. .

In this way, the acetylene polymer can be doped with a large amount of H2F cations without deteriorating the acetylene polymer. It is ideal for use in batteries and acetylene polymers that require high electrical conductivity. The conductive acetylene polymer of the present invention is an n-type semiconductor, and is not only useful as various electrical and electronic devices, but also can be easily combined with a p-type semiconductor to form a p-type semiconductor.
It is also possible to create -n junctions.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 [Manufacture of acetylene high polymer] A 5.1 m/! Add (15.0 mmol) of titanium tetrabutoxide, 20. A catalyst solution was prepared by dissolving OmJ in toluene and adding 5.4 ml (40 mmol) of triethylaluminum with stirring to react.

The reaction vessel was cooled with liquid nitrogen, the nitrogen gas in the system was evacuated using a vacuum pump, and then the reaction vessel was cooled to -78°C.

After rotating the reaction container to uniformly adhere the catalyst solution to the inner wall of the reaction container, immediately add 1
Polymerization was initiated by introducing purified acetylene gas at a pressure of atmospheric pressure. Simultaneously with the initiation of polymerization, an acetylene high polymer with metallic luster was deposited on the inner wall of the reaction vessel. The polymerization reaction was carried out at a temperature of -78° C. for 1 hour while maintaining the acetylene pressure at 1 atm, and then unreacted acetylene was evacuated with a vacuum pump to stop the polymerization. After removing the remaining catalyst solution with a syringe under a nitrogen atmosphere, washing was repeated six times with 100 ml of purified toluene while keeping the temperature at -78°C, and then vacuum drying was performed at room temperature.

At the portion where the catalyst solution adhered to the inner wall of the reactor, a film-like acetylene high polymer having an area equal to that portion, a thickness of 90 μm, and a cis content of 98 inches was obtained.

The electrical conductivity (direct current four probe method) of this film-like acetylene polymer was 2.5×10 Ω·m at 20°C.

[Doping experiment]

The acetylene polymer produced by the above method has a width of 0.
A small piece with a length of 5 crn and 2.0 crn was cut out and mechanically crimped and fixed to a platinum wire to serve as a cathode electrode.A platinum plate was used as the other electrode, and the concentration of H, F ・BF4 was 0.3 mol. /l! Using a propylene carbonate solution as an electrolyte, doping was carried out under constant current (1.0 mA) for 5 hours. After the doping was completed, the doped acetylene polymer film was washed repeatedly with propylene carbonate to obtain a doped acetylene polymer having a golden metallic luster. The composition of this doped acetylene polymer film was determined by elemental analysis [CH(H2F). ,
, 78″3x, and its electrical conductivity (DC four-terminal method)
was an n-type semiconductor with 720σ1 sub.

Comparative Example 1 Using the acetylene polymer obtained in Example 1, H3 used as the supporting electrolyte in the [doping experiment] of Example 1
Doping was carried out under the same doping conditions as in Example 1, except that KBu'nN5C704 was used instead of P-BP. The doped acetylene polymer was dark blue due to oxidative deterioration. The composition of the doped acetylene polymer with [CH(Bu' nN)0.171.
]x, and was an n-type semiconductor with an electrical conductivity of 12Ω·m.

Example 2 [Manufacture of acetylene polymer] II completely replaced with nitrogen gas! in a glass reactor of
Toluene 20 purified according to a conventional method as a polymerization solvent
0 ml, tetrabutoxytitanium 294 as catalyst
mmol and triethylaluminum 7,34 mmol
A catalyst solution was prepared by sequentially charging J moles at room temperature. The catalyst solution was a willow solution.

The reactor was cooled with liquid nitrogen, and the nitrogen gas in the system was exhausted using a vacuum pump. .

The reactor was cooled to -78° C., and purified acetylene gas at a pressure of 1 atmosphere was blown into the reactor while stirring the catalyst solution with a magnetic stirrer. At the beginning of the polymerization reaction, the entire system became agar-like, making stirring difficult. The polymerization reaction was continued for 24 hours while maintaining the acetylene gas pressure at 1 atm. The system was agar-like with a reddish-purple color. After the polymerization is completed, unreacted acetylene gas is removed and the temperature of the system is lowered to -78.
It was washed repeatedly four times with 200 mg of purified toluene while being kept at °C. The solution remained slightly brown even after washing, and the catalyst was not completely removed. The gel-like acetylene polymer swollen in toluene was in the form of uniform chips in which fibrous microcrystals were intertwined, and no powder or lump-like polymer was formed.

A part of the homogeneous gel was taken out and dried, and the amount of acetylene high polymer in the gel was measured, and it was found that the gel contained 10% by weight of the acetylene high polymer.
゛The above gel-like material has a thickness of 10wR, a length of 1001111+,
It was placed in a formwork with 50-mesh width, sandwiched between chrome-plated ferro plates, and press-molded at room temperature under a pressure of 100 kf/cm while removing toluene to form a flexible and strong film with a thickness of 5 mm. A film-like molded product was obtained.This film-like molded product had an electrical conductivity (measured by the DC four-terminal method) of 5×10 Ω.
・It was a Nishiki p-type semiconductor.

[Doping experiment]

In place of the acetylene polymer used in Example 1, the film-shaped molded product obtained by the above method was used, and as the supporting electrolyte, H3P- was used in place of H,,F+-BF; used in Example 1.
A doping experiment was carried out in exactly the same manner as in Example 1, except that doping was carried out using ClO4 for 7 hours, and a golden film having the composition (CH(H3P), 215) was obtained.

This film was an n-type semiconductor with an electrical conductivity of 99.0 Ω·m.

Example 3 Using the acetylene polymer obtained in Example 1, H2F was used instead of H3P-BF4 used as the supporting electrolyte in Example 1.
Doping was carried out in the same manner as in Example 1 except that ``''・A s F6 was used, and the composition was [CH(H
3P). , 70]X golden film was obtained. This film was an i-type semiconductor with an electrical conductivity of 850 Ω-·m.

Example 4 Example 2 was used instead of the acetylene polymer used in Example 1.
Using a film-shaped molded product of acetylene high polymer obtained in
[Doping experiment] was carried out in exactly the same manner as in Example 1 except that H3P-PF6 was used instead of H3P-BF used in Example 1 as the supporting electrolyte, and the composition was (CH
A golden film of (H3P)o,,ao''lx was obtained.

This film has an electrical conductivity of 520Ω-1・crn-1
It was an n-type semiconductor.

Claims (1)

[Claims] An electrically conductive acetylene polymer obtained by electrochemically doping a decacetylene polymer with H2F cations.