JPS6054348B2 - Method for manufacturing high-strength plastic molded products suitable for electrodes and conductors - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a high-strength plastic molded product suitable for electrodes and conductors.

That is, in the present invention, the expanded graphite powder and the graphite powder are subjected to a special hydrophobizing treatment, that is, to improve so-called 1-wetting with the resin, so that the relationship between the resin and the expanded graphite powder and the graphite powder is Furthermore, by molding a composite powder or kneaded mixture with a surfactant with extremely high mixing homogeneity using a molding machine such as a compression molding machine or an extrusion molding machine, or a molding mold, the characteristics of graphite can be sufficiently improved. The present invention relates to a method for manufacturing plastic molded products suitable for use in electrodes and conductors, particularly those having extremely high strength. In recent years, graphite-containing plastic molded products having the characteristics of graphite have been manufactured by adding carbon black or graphite powder to various thermoplastic resins, mixing them, and then molding them.

However, the conventional manufacturing method for graphite-containing plastic molded products is to simply mix graphite powder and thermoplastic resin powder in a V-type mixer, Henschel mixer, etc., and then mold this mixed powder in a compression molding machine, an extrusion molding machine, etc. The molding process is performed using a machine. In this case, because the graphite or carbon black and the thermoplastic resin powder have different shapes, particle sizes, specific gravity, interfacial properties, etc., it is difficult to obtain a uniform mixed powder, and furthermore, the so-called 1 wettability with the thermoplastic resin is poor. Therefore, the dispersion of carbon black and graphite powder in the molten resin becomes uneven in the heating section of the compression molding machine and extrusion molding machine, and therefore the dispersion of carbon black and graphite powder in the molded product is also uneven, resulting in physical problems. In addition to the mechanical properties (strength) and mechanical properties (strength), there are large variations in other properties of graphite, making it impractical. On the other hand, in order to improve the uniformity of mixing, methods of melt-blending graphite and thermoplastic resin, such as roll mixing and Panbury mixing, have been considered.

This method is a method in which a melt-mixed product is molded into a desired shape using a molding machine such as an extruder. However, although this method yields a molded product that is somewhat more uniform than the molded product obtained by the above-mentioned method, the hydrophilic groups adsorbed on the surface of the graphite powder during melt-mixing make it difficult to mix with the thermoplastic resin. 1. Wetting is poor and a complete graphite powder dispersion cannot be obtained. Therefore, even if this kneaded mixture is molded using a molding machine such as an extrusion molding machine, the graphite is not uniformly dispersed in the molded product, resulting in poor physical and mechanical properties (
There are large variations not only in strength) but also in other properties of graphite, making it impractical. Furthermore, in this method, it is difficult to add a large amount of graphite due to poor wetting with the thermoplastic resin. Furthermore, even if homogeneous mixing becomes possible, in order to fully bring out the characteristics of graphite, the amount of graphite added will increase and the fat content will decrease, making it difficult to obtain the strength required for plastic molded products. The current situation is that there is no such thing.

That is, if an attempt is made to improve the properties of graphite such as conductivity or lubricity, the strength will decrease, and conversely, if an attempt is made to improve the strength, the properties of graphite will decrease. For this reason, the range of use of graphite-containing plastic molded products is limited, and today there are products that have all the characteristics of graphite and are extremely strong.
For example, the emergence of graphite-containing plastic molded products suitable for electrodes and conductors is desired. The present invention was made to eliminate the above-mentioned drawbacks, and by making it possible to add a large amount of graphite powder and improving the affinity and miscibility with thermoplastic resin molding materials, so-called 1 wettability, Enables uniform melt mixing and uniform dispersion in the heating section of compression molding machines and extrusion molding machines, especially for extremely strong and sufficient graphite properties, and homogeneous electrodes and conductors with little variation. The purpose of the present invention is to provide a manufacturing method that can produce plastic molded products suitable for.

The present invention first involves crushing fibrous expanded graphite having a bulk specific gravity of 0.01 to 0.033, or further granulating it after crushing. Specific gravity 0.1~0
．． 01 expanded graphite powder and average particle size 0.1-100μ
graphite powder at (a) 700 to 1100°C, respectively.
(b) 700 to 1
High-temperature heat treatment in a hydrogen gas atmosphere at a temperature of 100°C, or
(c) High-temperature heat treatment in a methane gas atmosphere at a temperature of 700 to 1100°C, or (d) Wet treatment with an alkane hydrocarbon such as n-heptane, n-butane, n-octane, neopentane, or 3-methylpentane. or (e) wet treatment with an alkene hydrocarbon such as ethylene, propylene, butylene, 1-hexene, etc.
step (4) of hydrophobizing the hydrophobized powder;
(1) 5 to 90% by weight of hydrophobized graphite powder with an average particle size of 0.1 to 100μ, and (c) vinyl chloride resin, polyethylene resin, polypropylene resin, polyester resin, polyurethane resin, polyacrylic resin, polymethacrylic resin. , polyacetal resin, ethylene-vinyl acetate copolymer resin, styrene resin, etc., or a thermoplastic resin molding material of 5 to 9% by weight. A mixing step (B) of mixing into a uniform composite powder or uniform kneading and mixing of this uniformly mixed composite powder (I + mouth + C) or this uniform kneading mixture (I + mouth + The method is characterized by combining (A+B+C) with step (C) of molding c) into a desired shape using a desired mold using a molding machine such as a compression molding machine or an extrusion molding machine.

In addition, the present invention first crushes fibrous expanded graphite having a bulk specific gravity of 0.01 to 0.033, or after crushing, further granulates the particles with a particle size of 0.01 to 1. Bulk specific gravity 0.1~
0.01 expanded graphite powder and average particle size 0.1-100
(a) 7000 to 1100 μ graphite powder, respectively.
Vacuum high temperature heat treatment at a temperature of ℃ or (b) 7000~
(C) High temperature heat treatment in a methane gas atmosphere at a temperature of 7000 to 1100 °C; (d) n-heptane, n-butane, n-octane, neopentane, 3 - A step of hydrophobizing by performing a wet treatment with an alkane group hydrocarbon such as methylpentane, or (e) performing a wet treatment with an alkene group hydrocarbon such as ethylene, propylene, butylene, 1-hexene, etc. (4) and (a) Hydrophobized particle size 0.01-1wn1 bulk specific gravity 0
．． 1 to 0.01% by weight of expanded graphite powder, (1) 5 to 90% by weight of hydrophobized graphite powder with an average particle size of 0.1 to 100μ, and (d) dodecyl sulfuric acid. 1 to 5% by weight of a surfactant such as sodium, sodium alkylbenzene sulfonate, aliphatic soap resin acid soap, and (
c) One or more thermoplastics such as vinyl chloride resin, polyethylene resin, polypropylene resin, polyester resin, polyurethane resin, polyacrylic resin, polymethacrylic resin, polyacetal resin, ethylene vinyl acetate copolymer resin, styrene resin, etc. Mixing step (B)'' of mixing 5 to 9% resin molding material into a uniform composite powder, or uniform kneading, and the uniformly mixed composite powder (A+C+C+N). ) or this homogeneous kneaded mixture (
It is characterized by a combination (A+B''+C) with a step (C) of molding the A+C+C+D into a desired shape using a desired mold using a molding machine such as a compression molding machine or an extrusion molding machine. shall be.

That is, in the present invention, first, as described above, particles having a particle size of 0.01 to 1 Tmt that have been subjected to hydrophobization treatment (Step A) are used.
1 Expanded graphite powder with a bulk specific gravity of 0.1 to 0.01 and graphite powder with an average particle size of 0.1 to 100p are respectively prepared.

However, in this hydrophobization treatment, it is noted that when hydrogen is adsorbed to the powder, the powder shows hydrophobicity, and when oxygen is adsorbed, it shows hydrophilicity, and in the present invention, expanded graphite powder and graphite powder are As mentioned above, vacuum heat treatment at a temperature of 700 to 1100°C, reduction treatment by heating in a hydrogen gas atmosphere and methane gas atmosphere heating at a temperature of 700 to 1100°C, or n-
Butane, n-heptane, n-octane, neopentane,
Wet treatment is performed using an alkane group hydrocarbon such as 3-methylpentane or an alkene group hydrocarbon such as ethylene, propylene, butylene, 1-hexene. This hydrophobization treatment, that is, homogeneous miscibility with thermoplastic resin, so-called 1
In order to improve wetting, homogeneous mixing can be obtained extremely easily in melt mixing methods such as roll mixing, Panbury mixing, and Henschel mixing, which makes it possible to add a large amount of expanded graphite powder and graphite powder. , and to enable complete uniform dispersion with the thermoplastic resin molding material. Further, it is intended to enable complete uniform dispersion of the thermoplastic resin in the melt in the heating section of a molding machine such as a compression molding machine or an extrusion molding machine. Next, the bulk specific gravity of the expanded graphite powder was limited to 0.1 to 0.01 because
If it exceeds 0.1, the so-called entanglement between graphite powder and thermoplastic resin will become weak, and the physical and mechanical strength after molding will not improve, and if it is less than 0.01, the fluidity and miscibility of the powder will deteriorate. In other words, the uniformity deteriorates and segregation becomes significant, making both of them unacceptable. Next, the particle size of the graphite powder is limited to 0.1 to 100 .mu.m. If it is less than 0.1 .mu.m, it is usually difficult to obtain it industrially and the cost becomes high.

Moreover, if it exceeds 100 μm, the physical and mechanical strength of the molded product may decrease depending on the type of thermoplastic resin material, so it is not allowed. Next, prepared (a) hydrophobized particle size 0.01~
1 day, expanded graphite powder with bulk specific gravity 0.1-0.01 3-5
0% by weight and (mouth) hydrophobized average particle size 0.1-1
00 μ graphite powder 5 to 9 weight percent, (c) vinyl chloride resin, polyethylene resin, polypropylene resin, polyester resin, polyurethane resin, polyacrylic resin, polymethacrylic resin, polyacetal resin, ethylene vinyl acetate copolymer resin, A uniform composite powder or a uniform kneaded mixture with 5 to 9 weight percent of one or more thermoplastic resin molding materials such as styrene resin is obtained.

Therefore, the reason for limiting the quantity of the expanded graphite powder (i), that is, 3 to 5% by weight, is that if the amount is less than 3% by weight,
The physical and mechanical strength of the molded product does not improve, and the amount of saliva is 5%.
Exceeding this value not only increases cost but also adversely affects the properties of the graphite powder itself, so both are unacceptable.

Next, limit the quantity of the graphite powder, that is, 5 to
The reason for setting the amount of saliva at 9% is that if it is less than 5% by weight, the properties of the graphite powder itself, such as conductivity and lubricity, will not be sufficiently exhibited, and if the amount exceeds 9%, the physical and mechanical strength of the molded product will deteriorate. Both are not possible because they decrease.

Next, the reason why the quantity of the thermoplastic resin molding material (c) was limited, that is, from 5 to 9% by weight, was because if it was less than 5% by weight, physical and mechanical strength could not be obtained in the molded product.
If it exceeds the above range, the characteristics of graphite powder, namely conductivity and lubricity, cannot be obtained, and both are unsuitable.

Next, as a thermoplastic resin molding material, vinyl chloride resin is used, for example, Zeon 121 (trade name) manufactured by Nippon Zeon Co., Ltd.
Examples of polyethylene resins include, for example, commercial names such as Flocene and Flowback, manufactured by Seitetsu Kagaku Co., Ltd., and polypropylene resins, such as Mitsui Noblen J-700, manufactured by Mitsui Toatsu Chemical Co., Ltd. ．． Examples of polyester resins such as JH-G include Vylon 200 (trade name) manufactured by Toyobo Co., Ltd.
Polyurethane resins include, for example, Baraprene 22S and 25S manufactured by Nippon Polyurethane Co., Ltd.; polyacrylic resins include, for example, Acrypet and Acrycon manufactured by Mitsubishi Rayon Co., Ltd., and polyacetal resins include, for example, polyplastics. Styrene resins such as Giuracon M-90, M-270, manufactured by Mitsui Toatsu Chemical Co., Ltd., are available under the trade name Toporex 85, manufactured by Mitsui Toatsu Chemical Co., Ltd.
Ethylene-vinyl acetate copolymer resins such as 0, etc. can be used, for example, such as Ultracene (trade name, manufactured by Toyo Soda Kogyo Co., Ltd.), and styrene resins, such as Topolex (trade name, manufactured by Mitsui Toatsu Chemical Co., Ltd.) can be used.

In addition, in the present invention, the above-mentioned (a) 3 to 5 weight percent of the expanded graphite powder subjected to the hydrophobization treatment, the above-mentioned (b) 5 to 9 weight percent of the graphite powder subjected to the hydrophobization treatment, and the above-mentioned (c) heat Plastic resin 5~
9 weight%, and (d) sodium dodecyl sulfate, sodium alkylbenzene sulfonate, aliphatic soap,
A homogeneous composite powder or a homogeneous kneaded mixture with 1 to 5% by weight of a surfactant such as a resin acid soap is obtained.

Therefore, the reason for limiting the amount of surfactant (d), that is, 1 to 5% by weight, is that if it is less than 1% by weight, expanded graphite powder and By helping the so-called 1-wetting of graphite powder and thermoplastic resin molding material, it is possible to quickly and uniformly disperse graphite powder and thermoplastic resin molding material.Also, expanded graphite can be used in the heating section of molding machines such as compression molding machines and extrusion molding machines. It is impossible to quickly and uniformly disperse the powder or graphite powder and the thermoplastic resin molding material by promoting so-called one-wetting.

If it exceeds 5% by weight, the properties of graphite, ie, electrical conductivity, lubricity, and physical and mechanical strength as molded products tend to decrease, and this is not acceptable.

Next, as a mixing method, when the thermoplastic resin molding material is a powder, roll mixing method, Panbury mixing method, Henschel mixing method, ball mill mixing method, etc. can be used.

Furthermore, when the thermoplastic resin molding material is in the form of pellets or chips, it can be mixed by a roll mixing method, a Panbury mixing method, or the like. Next, in the present invention, the uniform composite powder or kneaded mixture obtained as described above is molded into a desired shape in a desired mold using a molding machine such as a compression molding machine or an extrusion molding machine.

The molding conditions are the same as those for ordinary resin molding, and for example, in extrusion molding, the conditions are as follows, although they differ somewhat depending on the type of thermoplastic resin.

Screw rotation 10-80r. p. m. , heating section temperature 7
0-310℃.

Further, as the molding machine, a compression molding machine, an extrusion molding machine, an injection molding machine, a blow molding machine, etc. can also be used.

The plastic molded product according to the present invention has the characteristics of graphite, that is, sufficient electrical conductivity and lubricity, and because of the so-called entanglement of expanded graphite powder, graphite powder, and thermoplastic resin molding material, it is extremely difficult to use physical machinery. It has excellent mechanical strength and has little variation.

It has uniform and good electrical conductivity and is suitable for electrodes and conductors. For example, conventional plastic bearings have lubricity,
The abrasion resistance is poor, and the addition of solid lubricants such as graphite has been considered, but the required physical and mechanical strength cannot be obtained by adding solid lubricants, so improvements are required. The bearing obtained according to the present invention has sufficient lubricity and wear resistance, and its physical strength is only 5 to 10% lower than that of plastic alone, so it has sufficient physical strength to withstand use. Moreover, the plastic molded article according to the present invention has improved physical and mechanical strength by 20 to 80% compared to a molded article to which only graphite powder is added. Moreover, because of its good conductivity, it becomes a highly reliable electrode or conductor. Furthermore, even after these molded products were heated to carbonize the thermoplastic resin, their physical and mechanical strength was found to be improved by 20 to 80% compared to products with only graphite powder added. .

This is also noteworthy. Furthermore, it goes without saying that the method of the present invention can also be applied to thermosetting resins.

Examples will be further described below.

Example 1 Expanded graphite powder with a particle size of 0.10 to 0.85wn and bulk specific gravity of 0.05 and graphite powder with an average particle size of 10μ were each
Hydrophobization was performed by vacuum heat treatment at a temperature of 00°C.

This (a) 1 weight% of hydrophobized expanded graphite powder,
(1) 7% by weight of graphite powder, which has also been subjected to hydrophobization treatment, and (3) 2% by weight (trade name: Zeon 121), a vinyl chloride resin molding material manufactured by Tamoto Zeon Co., Ltd., are uniformly melted in a hot roll mixer. After mixing (I + mouth + C), injection molding machine or
A conductive plate was obtained by molding using a compression molding machine. The strength of this conductive plate was improved by 65 to 75% compared to conventional products.
Of course, the conductivity was also sufficient and suitable for electrodes.
In addition, those that do not use the above-mentioned expanded graphite powder and those that do not undergo the above-mentioned hydrophobization treatment have weak mechanical strength, large variations in conductivity, and a decrease in the value. could not be used. Example 2 Particle size 0.1
9~0.95T! r! Expanded graphite powder with an n1 bulk specific gravity of 0.02 and graphite powder with an average particle size of 7 μm were each hydrophobized in a hydrogen gas atmosphere at a temperature of 800°C.

This (a) 2% amount of expanded graphite powder that has been subjected to hydrophobization treatment, (2) 6% amount of graphite powder that has also been subjected to hydrophobization treatment, and (
c) 20% by weight of a polyethylene resin molding material (trade name: Flocene UF-7, manufactured by Seitetsu Kagaku Co., Ltd.) was mixed uniformly using the Henschel mixing method (a + mouth + c), and molded using a compression molding machine. A conductive plate was obtained. The strength of this conductive plate was improved by 70 to 80% compared to conventional products. Of course, the conductivity was also sufficient. In addition, when the above-mentioned hydrophobization treatment is omitted, the conductivity is low and its dispersion is observed.
Mechanical strength was also low. Example 3 Expanded graphite powder with a particle size of 0.20 to 0.80Tf0n1 and bulk specific gravity of 0.08 and graphite powder with an average particle size of 3μ were each hydrophobized in a methane gas atmosphere at a temperature of 700°C.

This (a) 8% by weight of expanded graphite powder subjected to hydrophobization treatment,
(mouth) 22% by weight of graphite powder that was also hydrophobized and (
c) Polypropylene resin molding material (trade name Mitsui Noblen J-700 manufactured by Mitsui Toatsu Chemical Co., Ltd.) with 6% saliva content,
Melt and mix uniformly using hot roll mixing (I + mouth +
c) After that, it was molded using an injection molding machine or an extrusion molding machine to obtain a bearing and a bushing. The strength of this bearing bushing was improved by 70 to 80% compared to conventional products. Of course, the lubricity and wear resistance were also sufficient. This product was also suitable for electrodes and conductors. It has high mechanical strength and high conductivity.
Moreover, it was highly reliable with little variation. Example 4 Expanded graphite powder with a particle size of 0.20-0.80Twt1 and bulk specific gravity of 0.03 and graphite powder with an average particle size of 3μ were each
- Wet treatment with butane was carried out, and hydrophobization was also carried out by heating and drying.

This (a) 3% by weight of expanded graphite powder subjected to hydrophobization treatment,
(mouth) 25% by weight of graphite powder that was also hydrophobized and (
C) polyacetal resin molding material (product name: Jyuracon M-270 manufactured by Polyplastics Co., Ltd.) with a weight of 7%,
Melt and mix uniformly using hot roll mixing (I + mouth +
c) After that, it was molded using an injection molding machine to obtain a bearing and a bushing. The strength of this bearing and bushing was improved by 65 to 75% compared to conventional products. Of course, lubrication. It also had sufficient strength and abrasion resistance. Of course, it was suitable for electrodes and conductors. It has high mechanical strength and is reliable in practical use. Example 5 Expanded graphite powder/powder with a particle size of 0.05 to 0.4'', bulk specific gravity of 0.03, and graphite powder with an average particle size of 80 μm were each
Hydrophobization was performed by vacuum heat treatment at a temperature of 00°C.

This (a) 1% of hydrophobized expanded graphite powder,
(mouth) 60% by weight of graphite powder that was also hydrophobized and (
C) 20% by weight of a polyacrylic resin molding material (trade name: Acrycon, manufactured by Mitsubishi Rayon Co., Ltd.) and (d) 3% by weight of sodium dodecyl sulfate were uniformly mixed using Henschel mixing (A+B+C+N). ), and then molded using a compression molding machine to obtain a conductive plate. The strength of this conductive plate was improved by 50 to 60% compared to conventional products. Of course, the conductivity was also sufficient. It was suitable for electrodes and conductors. It was highly reliable in practice. Example 6 Expanded graphite powder with a particle size of 0.34 to 1.0- and bulk specific gravity of 0.01 and graphite powder with an average particle size of 5 μm were wet-treated with n-heptane and dried by heating. Then, we made it hydrophobic.

This (a) 1 weight% of expanded/expanded graphite powder that has been subjected to hydrophobization treatment, (1) 6 weight% of graphite powder that has also been subjected to hydrophobization treatment, (
C) 25% by weight of ethylene-vinyl acetate copolymer resin molding material (trade name: Ultrasen, manufactured by Toyo Soda Kogyo Co., Ltd.);
(d) Sodium alkylbenzenesulfonate 5% by weight
are mixed uniformly using the ball mill mixing method (I +
After that, it was molded using a compression molding machine to obtain a conductive plate. The strength of this conductive plate is 50 to 60 times stronger than conventional products.
% improved. Of course, the conductivity was also sufficient. It was also suitable for thin electrodes and conductors. Furthermore, even after the conductive plate was heated to carbonize the resin, its strength was improved by 40 to 50%. Example 7 Expanded graphite powder with a particle size of 0.05 to 0.65Tm1 and bulk specific gravity of 0.05 and graphite powder with an average particle size of 7μ were each subjected to wet treatment with ethylene and hydrophobized by drying under reduced pressure. Ta.

This (a) 3% by weight of expanded graphite powder subjected to hydrophobization treatment,
(mouth) 25% by weight of graphite powder that was also hydrophobized and (
C) 70% by weight of a styrene resin molding material (trade name TOPOLEX, manufactured by Mitsui Toatsu Chemical Co., Ltd.) and (d) 2% by weight of aliphatic soap are uniformly melted and mixed using hot roll mixing. ), and then molded using an extrusion molding machine or an injection molding machine to obtain a bearing. The strength of this bearing was improved by 65 to 75% compared to conventional products. Of course, the lubricity and wear resistance were also sufficient. Of course, this thing is an electrode,
It was also suitable for use as a conductor. It had high conductivity, little variation, high mechanical strength, and was reliable. Example 8 Expanded graphite powder with a particle size of 0.05 to 0.4- and bulk specific gravity of 0.06 and graphite powder with an average particle size of 30μ were each
Hydrophobization was carried out in a hydrogen gas atmosphere at a temperature of 0'C.

This (a) 9% by weight of expanded graphite powder subjected to hydrophobization treatment,
(mouth) 68% by weight of graphite powder that was also hydrophobized and (
C) Mix phenolic resin molding material (trade name PR-11078 manufactured by Sumitomo Bakelite Co., Ltd.) with a weight of 2% using Henjiel mixing (a + mouth + c), and mold it using a compression molding machine. A conductive plate was obtained. The strength of this conductive plate was improved by 70 to 80% compared to conventional products. Of course, the conductivity was also sufficient. It was also suitable for thin electrodes. First, in hot roll mixing and Henschel mixing, the time required to uniformly disperse the graphite powder that has been subjected to the hydrophobic treatment according to the present invention and the graphite powder that has not been subjected to the hydrophobic treatment is longer than that of the untreated powder. 100, the processed powder requires 30-50 and 112-113 hours.

In addition, the strength (bending strength) and conductivity of the molded products in each of the above examples will be listed.

Comparison of strength and conductivity

Claims (1)

[Scope of Claims] 1. Expanded graphite powder with a particle size of 0.01 to 1 mm and bulk specific gravity of 0.1 to 0.01, and graphite powder with an average particle size of 0.1 to 100μ, respectively, are heated at (a) 700° to (b) High temperature heat treatment in a hydrogen gas atmosphere at a temperature of 700° to 1100°C; (c) 70°C
High-temperature heat treatment in a methane gas atmosphere at a temperature of 0° to 1100°C, or (d) wet treatment with an alkane group hydrocarbon such as n-butane, n-heptane, n-octane, neopentane, 3-methylpentane, etc. or (e) step (A) of hydrophobizing by wet treatment with an alkene group hydrocarbon such as ethylene, propylene, butylene, 1-hexene, etc.; (a) the hydrophobized particles having a diameter of 0. 01~1mm, bulk specific gravity 0
．． 1 to 0.01 expanded graphite powder, 3 to 50% by weight,
(b) Average particle size 0.1 to 100 μm, which was also subjected to hydrophobization treatment
5 to 90% by weight of graphite powder, (c) vinyl chloride resin,
One or more thermoplastic resin molding materials such as polyethylene resin, polypropylene resin, polyester resin, polyurethane resin, polyacrylic resin, polymethacrylic resin, polyacetal resin, ethylene vinyl acetate copolymer resin, styrene resin, etc. 5 to 90 Mixing process (B) to make a uniform composite powder or to make a uniform kneading mixture with weight%
Then, this uniformly mixed composite powder (A + B + C) or this uniform kneaded mixture (A + B + C) is molded into a desired mold using a molding machine such as a compression molding machine or an extrusion molding machine. A method for manufacturing a high-strength plastic molded product suitable for electrodes and conductors, characterized by comprising a step (C) of forming into a shape and combining (A+B+C). 2. Expanded graphite powder with a particle size of 0.01 to 1 mm and bulk specific gravity of 0.1 to 0.01 and graphite powder with an average particle size of 0.1 to 100 μ, respectively, are (a) vacuum heated at a temperature of 700° to 1100°C. (b) High temperature heat treatment in a hydrogen gas atmosphere at a temperature of 700° to 1100°C; (c) 70°C
High-temperature heat treatment in a methane gas atmosphere at a temperature of 0° to 1100°C, or (d) wet treatment with an alkane group hydrocarbon such as n-butane, n-heptane, n-octane, neopentane, 3-methylpentane, etc. or (e) step (A) of hydrophobizing by wet treatment with an alkene group hydrocarbon such as ethylene, propylene, butylene, 1-hexene, etc.; (a) the hydrophobized particles having a diameter of 0. 01~1mm, bulk specific gravity 0
．． 3-50% by weight of expanded graphite powder of 1-0.01, (
b) 5 to 90% by weight of graphite powder with an average particle size of 0.1 to 100 μ which has also been subjected to hydrophobization treatment, and (d) sodium dodecyl sulfate, sodium alkylbenzene sulfonate,
1 to 5% by weight of a surfactant such as aliphatic soap or resin acid soap, and (c) vinyl chloride resin, polyethylene resin, polypropylene resin, polyester resin, polyurethane resin, polyacrylic resin, polymethacrylic resin, polyacetal resin, ethylene. One or more thermoplastic resin molding materials such as vinyl acetate copolymer resin, styrene resin, etc. 5
- 90% by weight into a uniform composite powder, or a mixing step (B)' where the mixture is uniformly kneaded, and this uniformly mixed composite powder (A + B + C + D), or this Combination with step (C) of molding the uniform kneaded mixture (A+B+C+D) into a desired shape using a desired mold using a molding machine such as a compression molding machine or an extrusion molding machine (A+B'+C) A method for producing a high-strength plastic molded product suitable for electrodes and conductors, characterized by comprising: