JP2759837B2 - Manufacturing method of carbon material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is capable of producing a variety of carbon materials from a porous material having pores with a very uniform pore size to a dense and high-strength material. More particularly, the present invention relates to a method for producing a graphitic or carbonaceous carbon material useful as a filter material, a jig in the glass industry, a mold material, and the like.

[Problems to be Solved by Conventional Techniques and Inventions] Conventionally, porous carbon materials used for filtration materials and the like are prepared by mixing a carbon powder, graphite powder with a thermosetting resin, pitch, tar, etc. as a binder, molding, Fired ones have been used. Since these materials have a nonuniform pore size and can be obtained only in a very brittle form, a method of mixing carbon fiber or the like as a reinforcing material has been proposed in addition to the above.

However, a sufficiently uniform pore size has not yet been obtained.

On the other hand, as a dense and high-strength carbon material, a material obtained by using a coke fine powder or the like as a raw material, using a pitch or the like having a high carbonization ratio as a binder, molding by a rapper press or the like, and firing,
Alternatively, glassy carbon obtained by molding, curing, and carbonizing a special thermosetting resin is known. The former requires large-scale equipment in the former, and the latter is liable to be deformed or cracked during firing, resulting in inconvenience in production such that large-sized ones cannot be obtained.

The present invention solves the above-mentioned problems of the prior art, has pores with a very uniform pore size, and from a high-strength porous material to a dense and high-strength carbon material, can be produced in a very simple manner. It is intended to obtain in the process.

[Means for Solving the Problems] As a result of earnest studies, the present inventors have found that the above object can be achieved by combining an infusible phenol resin and a fusible phenol resin by a mechanochemical method, followed by molding and firing. I found

That is, the present invention dry-mixes a powdery or spherical insoluble phenolic resin and a powdery or spherically meltable phenolic resin by a mechanochemical method, and cleans the surface of the insoluble phenolic resin with the meltable phenolic resin. , And then molded and cured under pressure, and then calcined and carbonized.

The powdery or spherical insoluble phenol resin used in the production method of the present invention is, for example, Univex C type or CX type (trade name of Unitika), Bellpearl R type (trade name of Kanebo Co., Ltd.) It is preferable to use one represented by, for example. Further, as the meltable phenol resin, it is preferable to use, for example, those represented by Univex S type or N type (trade name of Unitika), Bell Pearl S type (trade name of Kanebo Corp.) and the like.

The particle diameter of the insoluble phenol resin is preferably from 1 to less than 10 μm to obtain a dense carbon material, and preferably from 10 mμ to 1 mm to obtain a porous carbon material, and the meltable phenol resin is used to obtain a dense carbon material. In this case, when a porous carbon material is obtained at 20 to 30% by weight, a porous carbon material is added at a ratio of 5 to 10% by weight, and dry mixing is performed by a mechanochemical method. In this case, the fusible phenolic resin is preferably of the same particle diameter as the infusible phenolic resin, and the mechanochemical reaction uses a crusher, and the pressure for pressing the pestle against the mortar is 0.2 to 2.0 kg / cm ^2. , Pestle rotation speed / mortar rotation speed 1/1
It is preferable that the thickness of the layer of the mixture is 0.2 to 3.0 mm, because dry mixing can be performed efficiently. When mixing 1 batch at 1 to 7 kg, the mixing time may be 1 to 5 hours.

Next, the mixture is filled into a mold, and 10 to 1500 kg / cm ²
After being molded and cured by holding at 100 to 200 ° C. under pressure for 1 to 5 hours, it is fired and carbonized to 1000 to 3000 ° C. The rate of temperature rise at this time is preferably from 2 to 200 ° C./hr.

The above molding pressure is 100 kg /
It is preferably at least cm 2, but when a porous carbon material is obtained, it is preferable to appropriately adjust the particle diameter of the insoluble phenol resin and the amount of the meltable phenol resin within the above range.

According to the production method of the present invention, the helium gas permeability
5.0 × 10 ^{-3 to} 1.0 × 10 ^-10 cm / sec, bending strength 750 to 1200 kg / c
It is possible to obtain a high-strength and dense carbon material having a m ² strength and a high-strength porous carbon material having a porosity of 10 to 40% and a bending strength of 200 to 550 kg / cm ² .

EXAMPLES Hereinafter, the present invention will be described more specifically based on examples and comparative examples.

Example 1 Spherical infusible phenol resin having an average particle diameter of 5 μm (product name: UNIVEX CX-10, manufactured by Unitika Ltd.) 10
The pressure at which a pestle was pressed against a mortar with a mortar was set at 1.2 kg / cm ² with 00 g and 300 g of a meltable phenol resin having an average particle diameter of 20 μm (manufactured by Kanebo Co., Ltd., trade name: Bellpearl S-890). / Mortar rotation speed 3/1, mixture layer thickness 0.5
mm, and mixed for 2 hours to obtain an infusible phenol resin ball whose surface was coated with a fusible phenol resin.

Next, this resin ball was filled in a mold, and was molded by holding at 150 ° C. for 1 hour under a pressure of 200 kg / cm ² to have a thickness of 5 × 220 × 250 m
A molded product having a size of m was obtained. This molded body is placed under a nitrogen atmosphere for 1 hour.
The material was heated to 1000 ° C. at 0 ° C. × hr and calcined to obtain a carbon material. This carbon material was dense and free from cracks, had a helium gas permeability of 1.2 × 10 ⁻⁸ cm ² / sec, and a bending strength of 1020 kg / cm ² .

Comparative Example 1 The same infusible phenolic resin as used in Example 1
A carbon material was obtained under the same conditions as in Example 1 except that 1000 g and 300 g of the meltable phenol resin were mixed by a V-type mixer for 2 hours. However, many cracks were observed in the obtained carbon material, and a test piece for measuring the strength could not be obtained.

Examples 2-5 Same infusible phenolic resin as used in Example 1
A carbon material was obtained under the same conditions as in Example 1 except that 1000 g and 250 g of the meltable phenol resin were mixed under various pressures for pressing a pestle into a mortar. The characteristics are shown in Table 1.

Example 6 Spherical infusible phenolic resin having an average particle diameter of 250 μm (product name: UNIVEX C-200, manufactured by Unitika Ltd.) 1
The pressure at which a pestle is pressed against a mortar with a crusher of 000 g and 100 g of a meltable phenol resin having an average particle diameter of 20 μm (manufactured by Kanebo Co., Ltd., trade name: Bellpearl S-890) is 1.5 kg / cm ^2, and the rotation speed of the pestle / Mortar rotation speed 5/1, mixture layer thickness 1.2m
The mixture was mixed for 3 hours as m to obtain an infusible phenol resin ball whose surface was coated with a fusible phenol resin. Next, the resin ball is filled in a mold, and pressed at 150 ° C under a pressure of 80 kg / cm ^2.
After holding for a time, a molded product having a size of 10 × 200 × 200 mm was obtained. This molded body was heated and fired at 1200 ° C. at 100 ° C./hr in a nitrogen atmosphere to obtain a carbon material. This carbon material has a porosity
Although it was 35% porous, the flexural strength was 250kg / cm
² and high strength. When the pore size distribution was measured with a mercury porosimeter, about 90% of the pore size was concentrated in the range of 20 to 40 μm, and the pores were extremely uniform.

Comparative Example 2 Same infusible phenolic resin as used in Example 6
A carbon material was obtained under the same conditions as in Example 6, except that 1000 g and 100 g of the meltable phenol resin were mixed for 3 hours using a ribbon mixer. The obtained carbon material is porous with a porosity of 38%, the bending strength is as low as 65 kg / cm ² , and the pore size distribution
It was remarkably wide, 10 to 100 μm.

[Effects of the Invention] As is clear from the above examples, according to the method of the present invention, a dense carbon material to a porous carbon material can be easily obtained in a simple step, and the obtained carbon material is , Resulting in extremely high strength.

Therefore, the present invention is industrially extremely useful as a method for producing a carbon material.

Claims (2)

(57) [Claims] 1. A powdery or spherical insoluble phenolic resin and a powdery or spherical insoluble phenolic resin are dry-mixed by a mechanochemical method, and the surface of the insoluble phenolic resin is melted. A method for producing a carbon material, which comprises coating with a resin, molding and curing under pressure, and then firing and carbonizing. 2. The dry-mixing of the non-melting phenol resin and the melting phenol resin is carried out by a grinder in an amount of 0.2 to 2.0 kg.
^2. The method for producing a carbon material according to claim 1, wherein the method is performed under a pressure of / cm ² .