JPH0369370B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method of manufacturing an electrically conductive composite. Specifically, the present invention relates to a method for producing a conductive resin composite comprising a thermoplastic resin and a five-membered heterocyclic compound polymer.

[Conventional technology]

It is well known that five-membered heterocyclic compounds form insoluble and infusible polymers when exposed to oxidizing agents; for example, pyrrole is reacted with inorganic acids, iron chloride, benzoquinone,
Advances in Heterocyclic Chemistry (Advances in Heterocyclic Chemistry)
Heterocyclic Chemistry) Volume 15, page 67 (1973
year). Similarly, derivatives of furan and thiophene also form polymers. On the other hand, it is also known that membrane-like polymers of pyrrole, furan, and thiophene can be obtained by electrolytic polymerization in the presence of an appropriate electrolyte (for example, in Chemical Communications (JC
S.Chemical Communication) 1979 635 pages, Japan Journal of Applied Physics (Japan J.Apl.Physics) Volume 21 L562
(1982), Volume 23 L527 (1984)).

[Problem to be solved by the invention]

However, with conventional methods, the resulting polymer is insoluble and infusible and cannot be molded into the desired shape, and with electrolytic polymerization, although it is possible to form a specific film, the desired shape cannot be obtained. However, there was a problem in that it could not be made into a shape similar to that of the previous one and required expensive equipment.

The inventors of the present invention have conducted intensive studies on ways to solve the above problems, and have found that by using a specific polymerization method to create a composite resin of a thermoplastic resin and a five-membered heterocyclic compound, a resin composite that can be molded at low cost and is conductive. The present invention was completed based on the discovery that the present invention can be obtained by the following methods.

[Means for solving problems]

That is, the present invention is characterized in that thermoplastic resin particles impregnated with an oxidizing agent are stirred in a liquid medium in which a five-membered heterocyclic compound that does not substantially dissolve the oxidizing agent and the thermoplastic resin is dissolved. This is a method for manufacturing a conductive resin composite.

As the oxidizing agent used in the present invention, inorganic acids and metal compounds are effectively used. For example, inorganic acids include sulfuric acid, hydrochloric acid, nitric acid, chlorosulfonic acid, etc., and metal compounds include various compounds known as Lewis acids, namely aluminum, tin, titanium, zirconium, chromium, manganese, iron, copper, etc. , chlorides and sulfates of molybdenum, tungsten, ruthenium, palladium, platinum, etc.
Specific examples include nitrates and acetylacetonate compounds. Furthermore, organic compounds such as benzoquinone and diazonium salts can also be used. These oxidizing agents may be used alone or in combination of two or more.

The thermoplastic resin particles used in the present invention can be of any shape, and commercially available shapes such as pellets, powders, beads, etc. can be used as they are. For example, those manufactured on an industrial scale such as polyethylene, polypropylene, polyvinyl chloride, styrene-acrylonitrile copolymer, polycarbonate, polyester, and polyisopropylene can be used.

In the present invention, as for the shape of the thermoplastic resin particles, the shape of the particles before being impregnated with the above-mentioned oxidizing agent may be maintained as it is, or the shape of the particles may be changed when impregnated with the oxidizing agent as described later. , it is sufficient that it has an appropriate shape that is easily dispersed during contact treatment with a five-membered heterocyclic compound.

In the present invention, there is no particular restriction on the method of impregnating the thermoplastic resin with the oxidizing agent, and the following various methods can be employed. For example, a method in which a thermoplastic resin is dispersed in a solution containing an oxidizing agent, a method in which a thermoplastic resin and an oxidizing agent are dissolved in a solvent and then precipitated in a poor solvent for both, and a method in which a crystalline thermoplastic resin and an oxidizing agent are heated Examples include a method of dissolving and then cooling and solidifying, and a method of co-pulverizing an oxidizing agent and a thermoplastic resin.

In the present invention, the thermoplastic resin particles impregnated with the oxidizing agent obtained by the above method are then dispersed in a solvent that does not substantially dissolve the oxidizing agent and the thermoplastic resin, and stirred with a five-membered heterocyclic compound described below. Treat contact. Any solvent may be used as long as it does not substantially react with the oxidizing agent and the five-membered cyclic compound and does not substantially dissolve the oxidizing agent and the thermoplastic resin. For example, in the case of a combination of polypropylene and a metal halide, low-temperature pentane, hexane, benzene, toluene, etc. can be used. It is not necessary to add the entire amount of the five-membered heterocyclic compound at once; it can also be added gradually, and this method is particularly effective when using a solvent that does not easily dissolve the five-membered heterocyclic compound. be. The stirring process is generally carried out using an ordinary stirring blade, but it can also be carried out by circulating stirring using a slurry pump or the like.
There are no particular restrictions on the temperature and time for carrying out the stirring contact treatment, but in order to obtain a resin composite with good conductivity, the amount of the polymer of the five-membered heterocyclic compound in the resin composite relative to the thermoplastic resin must be adjusted. It is preferable to select the temperature and time such that the weight ratio is 0.1 to 2.
In particular, the reaction proceeds sufficiently at room temperature.

In the present invention, examples of the five-membered heterocyclic compound include pyrrole, furan, thiophene, selenophene, tellurofene, and derivatives thereof.

The conductive resin composite thus obtained is separated from the unreacted five-membered heterocyclic compound and the solvent by filtration and static separation. At this time, it is possible to remove the oxidizing agent if necessary, but when a Lewis acid is used as the oxidizing agent, the oxidizing agent acts as a dopant and improves conductivity, so the unreacted complex is simply removed. It is sufficient to simply remove the five-membered cyclic compound.

〔Effect of the invention〕

By carrying out the method of the present invention, it is possible to obtain a composite in which a comparatively large amount of a five-membered heterocyclic compound polymer is uniformly dispersed, so that it is moldable and has high conductivity. The complex can be easily obtained and has high industrial value.

〔Example〕

The present invention will be explained below with reference to Examples. In addition,
Parts in the examples indicate parts by weight.

Example 1 2.0 g of an oxidizing agent-impregnated resin obtained by co-pulverizing 1 part of ferric chloride with 4 parts of polypropylene and n-
Put 25ml of hexane into a glass container and add 5.0ml of pyrrole while stirring. After stirring at room temperature for 24 hours, the resulting polypyrrole complex was washed with cyclohexane and dried. The yield of the complex was 2.8 g. Also, the specific resistance of the hot pressed sheet is 8.0.
×10 ³ Ωcm.

Example 2 The same operation as in Example 1 was carried out using a high nitrile resin "Barex" (trademark, manufactured by Sohio ChemiCal Co., Ltd., USA) in place of polypropylene. The yield of the polypyrrole composite was 2.6 g, and the specific resistance of the pressed sheet was 1.7×10 ⁵ Ωcm.

Example 3 After impregnating 1 part of ferric chloride into 10 parts of polypropylene in methanol, 1.0 g of the oxidizing agent-impregnated resin obtained by drying and 25 ml of cyclohexane were placed in a glass container, and 4.0 ml of pyrrole was added while stirring. added.
After stirring at room temperature for 4 hours, the resulting polypyrrole composite was washed with methanol and dried. The specific resistance of the hot-pressed sheet was 1.3×10 ⁴ Ωcm.

Example 4 Using 5.0ml of thiophenone instead of pyrrole,
The same operation as in Example 1 was performed except that the reaction time was 96 hours. The yield was 2.6 g, and the specific resistance of the pressed sheet was 6.5×10 ⁶ Ωcm.

Example 5 The same procedure as in Example 1 was carried out except that 5.0 ml of furan was used instead of pyrrole and the reaction time was changed to 96 hours. The yield was 2.7 g, and the specific resistance of the pressed sheet was 7.8×10 ⁵ Ωcm.

Example 6 2.7 g of a composite was obtained in the same manner as in Example 1, except that ammonium persulfate was used instead of ferric chloride.
The specific resistance of the press sheet was 1.3×10 ⁴ Ω·cm.

Example 7 The yield of a composite obtained in the same manner as in Example 4 except that sulfuric acid was used instead of ferric chloride was 2.2 g, and the specific resistance of the hot-pressed sheet was 9.2×10 ⁶ Ω·cm.

Example 8 The yield of a composite obtained in the same manner as in Example 1 except that azobenzene was used was 2.1 g, and the specific resistance of the hot-pressed sheet was 8.1×10 ⁶ Ω·cm.

Claims (1)

[Claims] 1. A conductive resin composite characterized in that thermoplastic resin particles impregnated with an oxidizing agent are stirred in a liquid medium in which a five-membered heterocyclic compound that does not substantially dissolve the oxidizing agent and the thermoplastic resin is dissolved. How the body is manufactured.