JPS5842625A - Acetylene high polymer having improved oxidation stability - Google Patents

Abstract

PURPOSE:An acetylene high polymer excellent in oxidation stability, prepared by treating an (electroconductive) acetylene high polymer with a specified compound. CONSTITUTION:100pts.wt. acetylene high polymer prepared by polymerizing acetylene in the presence of a Ziegler-Natta catalyst or electroconductive acetylene high polymer prepared by doping the above acetylene higher polymer with an electron-donating compound or an electron-accepting compound as a dopant is dry-blended with 0.1-200pts.wt. compound of formulaI, wherein R<1> and R<2> are each a 15C or lower alkyl, cycloalkyl or aryl, R<3-8> are each H or a 15C or lower alkyl or aryl, X is -S- or a group of formula II and R<9> is R<3>. EFFECT:It is possible to obtain a p or n type semiconductor having an electrical conductivity of 10<-8>-10<3>OMEGA<-1>.cm<-1>. USE:A positive electrode active substance of lithium cell, electrode material of secondary battery, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to acetylene polymers with improved oxidative stability.

The powdered acetylene polymer obtained by polymerizing acetylene using a so-called Ziegler-Natsuta catalyst consisting of a transition metal compound and an organic compound has an electrical conductivity in the semiconductor region, and is therefore a suitable material for electrical and electronic devices. It is already known that it is useful as In addition, this powdered acetylene high polymer was BP%Bat, 1-10t,
"2, S02. No. 2. When treated with electron-accepting compounds (acceptors) such as HON, O It is already known that the electrical conductivity decreases by up to four orders of magnitude when treated with C (donor).
D.J.

Berets et al, Trans++ Fara
dy 苧oc, + 64.823 (1968)'l].

Furthermore, it is already known that a thin film of acetylene polymer having a fibrous microcrystalline (fibril) structure can be obtained under specific polymerization conditions (Japanese Patent Publication No. 4B-3258
No. 1). In recent years, 12, O12, Br2I OA , I B
The electrical conductivity of the acetylene polymer can be increased to 1O- by chemically doping with an electron-accepting compound such as r, As)s, SbF5, PF6, etc. or an electron-donating compound such as %Li to %Na. It is already known that it can be freely controlled over a wide range of 8 to 10'Ω-1 l (J, C, S, Ohem, Com
+nu,.

578 (1977), Phys. Rev. Lett.
+ 39.1o 8 (1977), J, Am,
Ohem, Soc, Zoo, 1013 (197
8).

J. Ohem, Phys., 69.5098 (
1978)].

Some of the present inventors have proposed a method for producing an acetylene polymer having a fibrous microcrystalline structure using a method different from the above method, and a method for molding the same (JP-A-55-128419, JP-A No. 55-129404). No. 55-142030,
No. 55-1457'lO, No. 55-145711,
56-10428, Japanese Patent Application No. 55-34687) and a method for producing an acetylene polymer with high electrical conductivity by treating an acetylene polymer with a new dopant (Japanese Patent Application Laid-open No. 55-129424, 55-1294
No. 25, No. 55-129426, No. 55-12942
No. 7, No. 55-143702, No. 55-143703
I have already proposed this issue.

However, the acetylene polymer, which is a useful semiconductor, and the conductive acetylene polymer obtained by doping this acetylene polymer with a dopant (hereinafter abbreviated as conductive acetylene polymer), It has the disadvantage of being easily subject to oxidative deterioration due to oxygen, and there has been a strong desire among those in the industry for an acetylene polymer and a conductive acetylene polymer with improved oxidation stability.

In view of the above points, the present inventors have conducted extensive studies on acetylene polymers with excellent oxidation stability, and have found that acetylene polymers or conductive acetate with alkyl groups, cycloalkyl groups, and aryl groups B5-R8 is an aqueous atom, an alkyl group having at most 15 carbon atoms, an aryl group, X is -S- or Ni, provided that W is a hydrogen atom, an alkyl group having at most i5 carbon atoms , represents an aryl (aryI) group. ] The acetylene high polymer and conductive acetylene high polymer treated with the compound represented by the above do not show that the fR stability is significantly improved; The present invention was achieved by discovering that it also has the effect of increasing the conductivity by several orders of magnitude.

The acetylene polymer and electrically conductive acetylene polymer of the present invention not only significantly improve oxidation stability, but also significantly increase the electrical conductivity of the acetylene polymer by several orders of magnitude. The acetylene polymer used in the present invention can be in any form such as powder, fiber, film, or gel, and can be prepared by conventional methods or the present invention. Some of them can already be produced by conventional methods (FLend.

Accad, Naz, Lincei, (8] 25
+ 3 (195g) s'% Kosho 48-3258
No. 1, JP-A-55-128419, JP-A No. 55-1294
No. 04, No. 55-1.42030, No. 55-1457
No. 10, No. 55-145711, No. 56-1042
No. 8, Patent Application No. 55-34687, J. Ohem,
Phys, +69(1), log-111(197
8)).

The conductive acetylene polymer obtained by doping the acetylene polymer used in the present invention with a dopant is obtained by doping the acetylene polymer with a four-electron donating compound (donor) or an electron-accepting compound (acceptor) as a dopant. ) is obtained by doping.

Among the dopants used in the present invention, electron-accepting compounds include (I) halogens such as iodine, bromine, and bromine iodide, (arsenic pentafluoride, antimony pentafluoride, silicon tetrafluoride, phosphorous pentachloride, Phosphorus pentafluoride, ferric chloride, aluminum chloride, aluminum bromide and?
metal halides, such as aluminum chloride; ) ky, (to) nato-2-cyanoethylene, nato-2-cyanoquinodimethane, floranil, 2,3-dichloro-5゜6-dicyazubabenzoquinone, 2,3-dibromo-5,6-dicyazubabenzoquinone, etc. In addition, examples of the 1[child compound include sodium, potassium, and cesium, but needless to say, they are not limited to these.

Methods for doping an acetylene polymer with these dopants include (I) bringing the dopant vapor into direct contact with the acetylene polymer; and (2) immersing the acetylene polymer in an inert organic solvent or water. One method is to introduce a dopant therein, but there is a method in which a dopant is doped in advance into a gel-like or swollen composition of an organic solvent and an acetylene polymer having a fibrillar structure, and then molded. It's okay.

Doping conditions such as temperature, time, or dopant concentration during doping cannot be unconditionally limited because they vary depending on the type of dopant used and the electrical conductivity of the acetylene polymer required; It is desirable that the temperature is 300°C or lower, preferably 200°C or lower. If the temperature during doping is 300° C. or higher, the acetylene polymer will deteriorate, which is not appropriate.

In the present invention, in addition to the chemical doping method described above, OtO-PF-1AsF6-56 AgF2-, 0F580. An electrically conductive acetylene polymer [J, 0.8. ehem, Oo
mmu,, l 97 L594, O&EN Jan
, 26.39 (1981), J.O.l.

Ohem, Commu, 1981, 317]
can also be used.

The amount of dopant to be doped in both chemical and electrochemical doping methods is at most 4.0% per mole of -(OH)- repeating units of the acetylene polymer.
It is 0 morti.

In this way, an electrically conductive acetylene polymer having an electrical conductivity of lθ' to 105Q″·01 can be produced.

Specific examples of the compound represented by the above general formula used in the present invention include 2,2'-methylene-bis(4-
methyl-6-1-butyl-phenol), 2,2'-thio-bis(4-methyl-6-t-butyl-phenol)
, 2,2'-methylene-bis(4-methyl-6-nonyl-phenol), 2,2'-methylene-bis(4-
ethyl-6-tert-butyl-phenol), 2,2'-iso-butylidene-bis(4,6-dimethyl-phenol), 2,21-dihydroxy-3,3'-di(α-methyl-cyclohexyl) -5,5'-dimethyl-diphenylmethane, 2,2'-methylene-bis(4-methyl-
6-cyclohexylfuenol), but it goes without saying that it is not necessarily limited to these.

The amount of the compound added to the acetylene high polymer or conductive acetylene high polymer is not particularly limited, but is generally 0.1 to 200 parts by weight per 100 parts by weight of the acetylene high polymer or conductive acetylene high polymer. It is in parts by weight, preferably 1 to 100 parts by weight. Added amount of compound is 0
If the amount is less than 1 part by weight, no sufficient effect of improving oxidation stability will be observed.On the other hand, if the amount added is more than 200 parts by weight, no particular advantage will be observed by increasing the amount.

Acetylene high polymers are -insoluble and infusible, and also easily undergo oxidative deterioration under heating. Therefore, it is not possible to melt the acetylene high polymer and knead the compound into it like a normal thermoplastic resin. Therefore, methods for treating an acetylene polymer or a conductive acetylene polymer with the above compound include, for example, (1) dry blending the compound with the acetylene polymer or conductive acetylene polymer; (11) The above compound is bath-dissolved in a suitable organic solvent, and the acetylene polymer or conductive acetylene polymer is immersed in this solution, or the solution is dissolved in an acetylene polymer or conductive acetylene polymer. A method in which the solvent is removed after coating or spraying on a polymer, and (ji) treatment by adding the above-mentioned compound to a gelatinous or swollen acetylene polymer or conductive acetylene polymer swollen with an organic solvent. There are ways to do this, but
It is not necessarily limited to these.

The acetylene polymer or electrically conductive acetylene polymer obtained in this way not only has significantly improved oxidation stability, but also has an electrical conductivity that is higher than that of the unadded compound a. This is an increase of several orders of magnitude compared to . Furthermore, if high electrical conductivity is required, there is no problem in doping the acetylene polymer treated with the compound with a conventionally known dopant in the same manner as described above.

The acetylene polymer or electrically conductive acetylene sieve linear polymer obtained by the method of the present invention is an organic semiconductor with good oxidation stability and an electrical conductivity in the range of lO to 10 Ω・α, It is not only useful as an electric/electronic device, but also very useful as a positive electrode active material for lithium batteries, an electrode material for secondary batteries, and a solar cell material. Further, the acetylene polymer obtained by the method of the present invention is a P-type or n-type semiconductor, and it is also possible to easily create a P-n junction by combining a P-type semiconductor and an n-type semiconductor.

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

Examples 1 to 5, Comparative Example [Manufacture of acetylene polymer] A 5.1 ml. (15.0 mmol) of titanium tetrabutoxide was added, dissolved in 20.0 mmol of toluene, and 5.4 rnt (40 mmol) of triethylaluminum was added with stirring to react to prepare a catalyst solution.

The reaction vessel was cooled with liquid nitrogen, the nitrogen gas in the system was evacuated with 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 having a full-scale luster was precipitated 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 purified toluene 100°C while keeping the temperature at -78°C, and then vacuum drying was performed in Muronishiki.

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

The electrical conductivity (DC two terminal method) of this film-like acetylene polymer was 2.5 x 1o-80-1 il at 20°C. [Treatment with compounds] The compounds shown in Table 1 were Oxygen and water were previously removed by vacuum degassing.

The compound shown in H-1 was dissolved in toluene and 01 mo
A toluene solution of l/t was prepared, and the film-like acetylene polymer prepared by the above method was immersed in the above toluene solution for 40 hours under a nitrogen atmosphere. After immersion, toluene was removed by vacuum degassing at room temperature. Next, this film-like acetylene polymer was left in the air for 20 days, and the electrical conductivity (direct current two terminal method) was measured before and after being left. In addition, the amount of the compound attached to the film-like acetylene polymer was determined from the increase in the amount of the compound after immersion in toluene. The results are summarized in Table-1.

Example 6 [Manufacture of acetylene high polymer] Into 14 glass reactors completely purged with nitrogen gas, 200 g of toluene purified according to a conventional method was added as a polymerization solvent.
A catalyst solution was prepared by sequentially charging 2.94 mmol of tetrabutoxytitanium and 7.34 mmol of triethylaluminum as a catalyst at room temperature. The catalyst solution was a homogeneous solution. Next, one reactor was cooled with liquid nitrogen, and the phosphorus 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 the catalyst solution was left standing. At the beginning of polymerization, the entire system became agar-like. The polymerization reaction was continued for 10 hours while maintaining the pressure of the acetylene gas at 1 atm. The system was agar-like with a reddish-purple color. After the polymerization was completed, unreacted acetylene gas was removed, and the system was washed four times with 200-g purified toluene while keeping the temperature at -78°C. A swollen acetylene polymer was obtained. This swollen acetylene polymer was a swollen product in which fibrous microcrystals (fibrils) with a diameter of 300 to 500 were regularly intertwined, and no powder or lump-like polymer was produced.

This sheet-like swollen acetylene polymer was sandwiched between chromium-plated ferro plates, pre-pressed at room temperature at a pressure of 100 to 9/crl, and then 1 s ton/c+! A uniform and flexible acetylene polymer film with a reddish-brown metallic luster and a thickness of 120 μm was obtained by high-pressure pressing at a pressure of . Watch this film at 5 o'clock.

The bulk density of the obtained acetylene polymer film (vacuum dried at room temperature) was 1.05 f//Co, and observation with an electron microscope showed that the film was non-porous.

In addition, this acetylene-shoden composite film contains 90% violet.
Electrical conductivity at 0°C and 20°C (DC four-terminal method) is 4.8
[Addition of compound] The acetylene polymer obtained by the above method was used in place of the acetylene polymer used in Examples 1 to 5. 2 was carried out in exactly the same manner as in Examples 1 to 5, except that
．． Treatment with 2'-methylene-bis(4-methyl-6-1-p, methyl-phenol) was carried out. The amount of the compound deposited was 52.

In addition, the electrical conductivity (DC two-terminal method) before exposure to air is 2.2×10 Ω・α, and the electrical conductivity is 1! The electrical conductivity of the ridge is 5. l×10 Ω・crn
''.On the other hand, the electrical conductivity of the acetylene polymer without any compound added was 4.8 x 10-70- before exposure.
1.crIvl, after 10 days in the air 87
×10-8Ω-1·dl.

Example 7 [Doping] The film-like acetylene polymer with a cis-containing content of 98% obtained in Example 1 was placed in a flask, and after evacuating the air with a vacuum pump, iodine scum was removed using the vapor pressure of iodine at room temperature. After introducing 3
This film-like acetylene polymer was treated with iodine gas for an hour. After the treatment, unreacted iodine was evacuated using a vacuum pump to obtain an iodine-doped conductive acetylene polymer. The electrical conductivity (direct current four probe method) of the electrically conductive acetylene polymer was 5250-1·tM"-' at 20°C.

[Treatment with compounds]

2,2'-methylene-bis(4-methyl-
A 0.1 mol/l toluene solution of 2,2'-methylene-bis(4-
Methyl-6-deuter-butyl-phenol) is 18.1 weight tons
An electrically conductive acetylene polymer with qb attached thereto was obtained. Electrical conductivity of conductive acetylene polymer with (DC four-terminal method)
was 560Ω·α at 20°C.

After exposing this conductive acetylene polymer to the air for 20 days, its electrical conductivity was 470Ω. ) After exposing the conductive acetylene polymer doped with iodine to the air for 20 days, the electrical conductivity was 2.2Ω・crn″′″1; Patent applicant: Showa Denko K.K. Person Patent Attorney Sei Kikuchi

Claims (1)

[Scope of Claims] An acetylene polymer, or a conductive acetylene polymer obtained by doping this acetylene polymer with a dopant, is an acetylene polymer having an alkyl group, a cycloalkyl group, an aryl group of the general formula
l') Group R5-R8 is a hydrogen atom, an alkyl group having at most 15 carbon atoms, aryl (aTyl)
Indicates the group. ] An acetylene polymer with improved oxidation stability obtained by treatment with a compound represented by: