JPH0360873B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention is applicable to, for example, packaging materials for electronic device parts that require electromagnetic shielding and antistatic properties, and flooring and wall materials used in places where static electricity generation is averse, such as electronic device assembly lines. The present invention relates to a conductive composite powder used as a raw material for manufacturing various conductive products such as anti-static shoes, and a method for manufacturing the same. [Prior art] In recent years, the destruction of semiconductor components such as ICs and LSIs due to static electricity has become a major problem, and malfunctions of electronic equipment due to electromagnetic waves have become a focus of attention.As a result, containers for storing ICs, etc. It is necessary to provide antistatic properties not only to IC assembly plants and packaging materials, but also to provide electromagnetic shielding to the housings of computers and other devices. Products with this effect are becoming widely used. Products with this type of conductivity include those molded from conductive resins such as polyacetylene, where the polymer itself is conductive, and those molded from conductive resin compositions in which conductive fillers are mixed into resin or rubber. Alternatively, molded products made from antistatic compositions in which antistatic properties are mixed into resin are known, but generally carbon powder, metal flakes,
Products molded from resins or rubbers that have been mixed with conductive fillers such as metal fibers, metal powders, and metallized particles, and antistatic agents such as surfactants to impart conductivity are used. Also known are resins imparted with electrical conductivity by vapor deposition of metals such as gold and palladium or metal oxides such as indium oxide, or by electrolytic oxidative polymerization of pyrrole. [Problems to be solved by the invention] However, when a conductive filler is mixed into a resin or rubber to impart conductivity, the conductive filler is added to the resin or rubber and when kneaded, the conductive filling is There were problems with the dispersibility of the agent, resulting in non-uniform conductivity, and when the amount of conductive filler added to improve conductivity was increased, the strength of the resin decreased. Furthermore, the method of imparting conductivity by incorporating an antistatic agent has the disadvantage that the antistatic agent tends to flow out of the resin and be lost, resulting in a decrease in conductivity. Furthermore, if it is necessary to increase the volume or reduce the weight of the product as well as impart conductivity, synthetic resin particles, natural polymer particles, rubber powder, inorganic powder, etc. may be used in addition to conductive fillers and antistatic agents. Although general fillers are used in combination, there is a problem in that when these fillers are used in combination, sufficient conductivity may not be imparted. On the other hand, the methods of vapor depositing metals and metal oxides and the electrolytic oxidative polymerization of pyrrole have problems in that the manufacturing costs for vapor deposition and electrolysis are high and that they require complicated manufacturing equipment. [Means for Solving the Problems] As a result of intensive research in order to solve the above-mentioned problems, the present applicant immersed materials to be conductively treated, such as plastic films, sheets, or molded products, in a treatment liquid and performed the treatment. A conductive composite consisting of an electronically conjugated polymer and a conductive material is produced by bringing a monomer capable of forming an electronically conjugated polymer into contact with an oxidative polymerization agent in a liquid, and polymerizing the monomer in the presence of a dopant. However, as a result of further intensive research in order to increase the efficiency of using the processing liquid, we found that synthetic resin powder and granules were used as the conductive material. using
The powder or granules are dispersed in a non-solvent, brought into contact with a pyrrole-based monomer and an oxidative polymerization agent in the non-solvent, and the monomers are polymerized in the presence of a dopant to form a pyrrole-based polymer on the surface of the powder or granules. According to the method of forming a conductive composite powder by coating or impregnating part or all of the pyrrole-based polymer in the powder, the amount of the pyrrole-based monomer used is extremely minimal, and the yield is substantially 100%. %, a conductive composite synthetic resin powder consisting of a pyrrole polymer and a powder can be formed, and furthermore, unlike the conventional method, precipitation of the pyrrole polymer is hardly observed, and the pyrrole monomer With no waste,
The resulting conductive composite synthetic resin powder can be molded into products of various shapes, and products with excellent conductivity can be obtained.Moreover, these conductive composite resin powders can be used as conductive fillers. Even when it is kneaded into a resin and used, there is no risk that the conductivity imparted to the molded product obtained from this resin will be uneven, and it can be used not only as a filler for simply imparting conductivity. They have discovered that it can be effectively used as a filler to increase the weight and weight of products, and have completed the present invention. Specifically, one aspect of the present invention is a conductive material characterized in that the surface of the synthetic resin powder is coated with a pyrrole-based polymer, or the powder or granule is partially or entirely impregnated with a pyrrole-based polymer. This paper focuses on composite powder and granular materials. Another aspect of the present invention is to disperse synthetic resin powder in a non-solvent, bring it into contact with a pyrrole monomer and an oxidative polymerization agent in the non-solvent, and polymerize the monomer in the presence of a dopant. The gist of the present invention is a method for producing a conductive composite powder, which is characterized by obtaining a conductive composite powder consisting of a resin powder and a pyrrole polymer. The conductive composite powder of the present invention has a structure in which the surface of the powder is coated with a pyrrole polymer, or the surface of the powder is coated with a pyrrole polymer and the powder is coated with a pyrrole polymer. It has a structure in which part of the pyrrole-based polymer is impregnated, or it has a structure in which the pyrrole-based polymer is entirely impregnated in the powder body. The synthetic resin powder particles also include foamed particles and porous particles of synthetic resin. It is preferable that these powders and granules have surface porosity because the composite strength with the pyrrole polymer is increased and, as a result, durable conductivity can be obtained. The particle size of the synthetic resin powder is between 25 and 25, which can be used for molding such as injection, compression, extrusion, blow molding, and bead foam molding.
320 μm is preferred. The production method of the present invention involves dispersing synthetic resin powder in a non-solvent, and polymerizing the pyrrole monomer by bringing the powder into contact with a pyrrole monomer and an oxidative polymerization agent in the presence of a dopant in the non-solvent. The synthetic resin powder and the pyrrole polymer are composited together to obtain a conductive composite powder which is imparted with conductivity by the pyrrole polymer. Base resins for synthetic resin powder include polyvinyl alcohol, cellophane, cellulose ester,
Polyvinyl acetate, polyvinyl formal, polyvinyl butyral, polyvinyl chloride, polyvinylidene chloride, polyvinylidene fluoride, chlorinated polyethylene, polyethylene, polypropylene, polymethyl methacrylate, polycarbonate, polyethylene terephthalate, polybutylene terephthalate,
6-nylon, 11-nylon, 12-nylon, 66
- Thermoplastic resins such as nylon, polymers of ionic electrolyte monomers, or copolymers of these monomers and other monomers are used alone or in combination. 6
- In the case of resins with high water absorption such as nylon, the pyrrole polymer tends to be almost completely impregnated into the resin particles, and in the case of resins with low water absorption such as polyvinyl chloride, The pyrrole polymer is likely to be formed so as to cover only the surface of the resin powder. Examples of pyrrole monomers include pyrrole, 3-methylpyrrole, N-
Examples include methylpyrrole. Water is used as a non-solvent to disperse the powder, but the surface of the powder is roughened to improve the adhesion of the pyrrole polymer to the surface of the powder and/or the impregnation into the powder. An organic solvent may be added for this purpose. Examples of organic solvents include aliphatic alcohols such as methanol and ethanol; aliphatic ketones such as acetone and methyl ethyl ketone; ethers such as diethyl ether and tetrahydrofuran; halogenated hydrocarbons such as methylene chloride and chloroform; ethyl acetate and acetic acid. Esters such as butyl; aromatic hydrocarbons such as toluene and benzene; aliphatic hydrocarbons such as hexane; nitrogen-containing compounds such as acetonitrile and benzonitrile; dimethylformamide and mixtures thereof; Monomer from inside,
They are appropriately selected and used depending on the dopant, the oxidative polymerization agent, and the material of the powder. As the above-mentioned dopant, all commonly used acceptor dopants can be used. Acceptor dopants include halogens such as chlorine, bromine, and iodine; Lewis acids such as phosphorus pentafluoride; protonic acids such as hydrogen chloride and sulfuric acid; transition metal chlorides such as ferric chloride; silver perchlorate; Examples include transition metal compounds such as silver boron fluoride. As an oxidative polymerization agent, permanganic acid (salt) such as permanganic acid or potassium permanganate is used.
Chromic acids such as chromic trioxide; Nitrates such as silver nitrate; Halogens such as chlorine, bromine, and iodine;
Peroxides such as hydrogen peroxide and benzoyl peroxide; Peroxo acids and peroxo acid salts such as peroxodisulfuric acid and potassium peroxodisulfate; Oxygen acids and acid salts such as hypochlorous acid and potassium hypochlorite; Chloride Examples include transition metal chlorides such as ferric iron; metal oxides such as silver oxide. Among these oxidative polymerization agents, halogens, peroxo acids (salts), transition metal salt compounds, etc. act as dopants, so when these are used as oxidative polymerization agents, it is especially important to use other dopants together. Although not necessary, when used in combination with the above dopants, the conductivity can be further improved. An example of a method of dispersing the powder in a non-solvent and contacting it with a pyrrole monomer and an oxidative polymerization agent in the presence of a dopant is to disperse it in a non-solvent solution containing the monomer, an oxidative polymerization agent, and if necessary, a dopant. , a method of immersing, stirring and dispersing the powder before the monomer is substantially polymerized, and adding the powder to a non-solvent solution containing an oxidative polymerization agent and, if necessary, a dopant, and a non-solvent solution containing the monomer. A method of sequentially immersing the body and stirring and dispersing it,
Examples include a method in which the powder is immersed in a non-solvent solution containing an oxidative polymerization agent and, if necessary, a dopant, and then stirred and dispersed, and then the monomer is added to this solution. According to the method described above, the processing time can be shortened, but since the polymerization reaction of the pyrrole monomer is fast, it is necessary to immediately immerse the powder into the solution and disperse it after preparing the solution. If time elapses between immersing the body in the solution and dispersing it, the compositing of the powder and the pyrrole polymer tends to deteriorate, resulting in a decrease in conductivity. In addition, since oxidative polymerization agents have lower permeability into powder and granules than monomers, we adopt a method in which the treatment with a monomer-containing solution and the treatment with an oxidative polymerization agent-containing solution are performed separately, as in the method of . After immersing and dispersing the powder in a solution containing an oxidative polymerization agent for about 20 minutes to 1 hour, it is preferable to contact it with a pyrrole-based monomer. By improving the degree of impregnation of the polymer into the powder, more durable conductivity is imparted. The temperature of the treatment liquid when dispersing the powder in a non-solvent is preferably from 0 to 40°C, particularly preferably from 0 to 5°C, in order to further improve the imparted conductivity.
In addition, the processing time for powder and granules depends on the resin material of the powder and granules.
Although it varies depending on the desired degree of conductivity and the concentration of monomer and oxidative polymerization agent, it is usually 1 minute to
It takes about 3 hours. [Example] Hereinafter, the present invention will be explained in more detail with reference to Examples. Example 1 1000 g of polyvinyl chloride resin particles (degree of polymerization 800, particle size 50 to 100 μm) was placed in the round bottom flask of Example 1 5, and 0.2 M ferric chloride aqueous solution 2 was added and stirred to disperse the resin particles. , and cooled until the temperature reached 2-3°C. Next, stirring was continued for 30 minutes at the same temperature, and then 400 ml of a 0.2M pyrrole monomer aqueous solution was added, and the mixture was further maintained at 2 to 3°C and vigorously stirred for 1 hour. This dispersion was filtered, thoroughly washed with distilled water, and then dried at 50°C to obtain gray resin particles. As a result of observing the resin particles using an electron microscope, it was found that no particles with a size of 50 μm or less were observed, and that only pyrrole polymer was not produced. Furthermore, the resin particles were filled into a container with a volume of 21.1 ml, and the resistance value between the electrodes (5.85 cm) was measured with a tester, and the result was 1.6×10 ⁴ Ω, indicating excellent conductivity. Furthermore, a film with a thickness of 0.1 mm was formed using these resin particles, and the surface resistance value and visible light transmittance of this sheet were measured, and the results were 3 x 10 ³ Ω/cm.
(25℃, 50%RH), the desired conductivity is 40%,
It had transparency. Note that the surface resistance value is a value measured using a high resistance meter, and the visible light transmittance is an integral value of a value measured at 400 to 800 nm using a spectrophotometer. Examples 2 to 5 The resin particles shown in Table 1 were treated in the same manner as in Example 1 to obtain gray resin particles. As a result of observing the resin particles using an electron microscope, it was found that the pyrrole polymer was impregnated into the resin particles. The resistance value of the resin particles was measured in the same manner as in Example 1, and the results are shown in Table 1. Example 6 Pyrrole monomer aqueous solution concentration from 0.2M to 0.4M
The same resin particles as in Example 1 were treated in the same manner except that black resin particles were obtained. The resistance value of the resin particles was measured in the same manner as in Example 1 and was found to be 2×10 ³ Ω. In addition, a film with a thickness of 0.1 mm was formed using these resin particles, and the surface resistance value and visible light transmittance of this film were measured in the same manner as in Example 1. As a result, they were each 1.2 × 10 ³ Ω/cm.
(25°C, 50%RH) and 32%. Comparative Example 1 A polyvinyl chloride film wound into a roll with a thickness of 0.1 mm x width of 20 cm x length of 500 cm was immersed for 30 minutes in the 0.2 M ferric chloride aqueous solution of 2 kept at 2 to 3°C. 400 ml of 0.2M pyrrole monomer aqueous solution was added to this solution, stirred vigorously, and maintained for 1 hour. Next, the film was taken out, washed with distilled water, dried at 50°C ^, and the surface resistance and visible light transmittance of the film were measured in the same manner as in Example 1. 50%RH),
However, the incorporation of the pyrrole polymer into the polyvinyl chloride film was 1.5%, which was extremely poor.

〔Effect of the invention〕

As explained above, in the conductive composite powder of the present invention, the surface of the synthetic resin powder is coated with a pyrrole-based polymer, or a part or all of the pyrrole-based polymer is impregnated into the powder. The conductive composite powder of the present invention can be molded to easily obtain a molded article of any shape having excellent conductivity. Furthermore, the conductive composite powder of the present invention can be used as a conductive filler, etc. Since the conductive composite powder of the present invention has good dispersibility in resin, it can be added to resin as a conductive filler. Even when used, uniform conductivity can be imparted, and it is made conductive without impairing the original performance of the powder or granule.
Powder and granules can be used as they are for conventional purposes, and can be effectively used as electrically conductive fillers, weight-reducing materials, etc. There is no need to use materials together, and all the drawbacks of the conventional methods of using bulking materials and lightweighting materials in combination can be overcome. In addition, when used as a conductive filler by adding it to a resin, etc., if a conductive composite powder made of a resin, etc. that is compatible with the resin to which the filler is added is used, and a conductive composite powder is treated with pyrrole, carbon black can be used. There is no possibility of reducing the mechanical strength as in the case of using In addition, the method of the present invention involves dispersing synthetic resin powder in a non-solvent, bringing it into contact with a pyrrole-based monomer and an oxidative polymerization agent in the non-solvent, and polymerizing the pyrrole-based monomer in the presence of a dopant to form a pyrrole-based polymer. and synthetic resin powder, forming a composite consisting of
Since the method of imparting conductivity using a pyrrole polymer is adopted, conductive composite powder can be produced reliably and easily. In addition, the method of the present invention can produce excellent conductive composite powder at a high yield even when the amount of pyrrole monomer used is extremely low, and moreover, it can be produced efficiently with less waste of the pyrrole monomer. Furthermore, in the method of the present invention, even when the powder is made of a transparent resin, conductivity can be imparted without substantially impairing the transparency of the resin, and the resulting conductive composite powder can be molded. Sheets, films, etc., obtained by this method have various effects such as being highly transparent.

Claims (1)

[Scope of Claims] 1. A conductive material characterized in that the surface of the synthetic resin powder is coated with a pyrrole-based polymer, or the powder or granule is partially or entirely impregnated with a pyrrole-based polymer. Composite powder. 2 The synthetic resin powder is dispersed in a non-solvent, brought into contact with a pyrrole-based monomer and an oxidative polymerization agent in the non-solvent, and the monomer is polymerized in the presence of a dopant to form the synthetic resin powder and the pyrrole-based polymer. 1. A method for producing a conductive composite powder, the method comprising obtaining a conductive composite powder consisting of: