JPH01320208A - Production of molded glassy carbon plate - Google Patents

Abstract

PURPOSE:To efficiently produce a thick glassy carbon plate without causing bubbling or cracking during carbonization by combining phenol resin with cellulose fibers contg. drying oil and by carbonizing them by burning under prescribed conditions. CONSTITUTION:Drying oil is uniformly incorporated into disintegrated cellulose fibers and these fibers contg. the drying oil are mixed with phenol resin. This mixture is molded to obtain a molded body of a prescribed shape and this molded body is carbonized by burning at >=800 deg.C in a nonoxidizing atmosphere.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention can produce not only a thin plate but also a thick glass-like carbon molded plate that does not cause foaming or cracking during sintering and carbonization. Concerning possible manufacturing methods.

[Conventional technology]

Since glassy carbon has excellent gas sealing properties, chemical resistance, and electrical conductivity, it is widely used in the fields of fuel cells and electronic materials Y81.

However, the excellent gas sealing properties have the opposite effect,
In conventional manufacturing methods, the gas generated during the calcination carbonization process is trapped inside and is difficult to be discharged to the outside, which often causes foaming and cracking during the calcination carbonization process.

As a method to solve the above problems, the present inventors first focused on the network of chemical bonds in phenolic resin, and by using a drying oil-modified phenolic resin, the gas generated can be easily released, and the cracks can be easily released. We would like to propose a method for manufacturing glass-like carbon plates that does not cause such problems.
1470).

[Problem to be solved by the invention]

However, even with the above method, it is not easy to manufacture a thick glass-like carbon plate, for example, a plate with a thickness of 2 MR or more.

As a result of intensive research in order to obtain a thick glass-like carbon molded plate, the present inventors found that it was possible to use a combination of phenol resin and cell fiber containing drying oil as a raw material for firing. I found it to be effective.

The present invention has been made based on the above-mentioned discovery, and an object of the present invention is to provide a manufacturing method that can efficiently produce a glass-like carbon molded plate that is much thicker than conventional laminates.

(Means for Solving the 81 Problems) In order to achieve the above object, in the production method of the present invention, cellulose fibers containing drying oil and a resin are mixed, and the mixture is shaped to produce a product. The cedar board is fired and carbonized at a temperature of 800° C. or higher in a non-oxidizing atmosphere.

Cellulose fiber t containing drying oil used in the present invention
Well, it is made by uniformly containing a predetermined amount of drying oil in unraveled cellulose fibers.

Examples of the above-mentioned drying oil include tung oil, 7-niura oil, and eno oil.

The NOL resin may be a normal one or one modified with a drying oil.

The above mixture is mixed with a kneader or the like to give a
After producing a green cedar board by pressure forming at a temperature of 0°C, it is sandwiched between graphite plates, etc., and then fired and carbonized at a temperature of 800°C or higher.

The reason why foaming, cracking, etc. do not occur during the calcination carbonization process is not clear, but it is thought to be as follows.

That is, drying oil is extracted in the cellulose fiber bundle. When this is mixed with a phenol resin, the drying oil is present in the cellulose fiber bundle, so it cannot be completely buried by the phenol resin. Furthermore, since pressure molding is performed at a relatively low temperature, drying oil remains in the formed plate.

Therefore, when this is subjected to firing and carbonization treatment, the drying oil is initially scattered, a passage is formed, and the cracked gas generated is released through this passage. This passageway disappears during the process of charcoal shrinkage when fired at 800°C or higher.

The land of drying oil contained in the cellulose is 10 to 3 o
A range of wt% is appropriate. Contains 1 drying oil vinegar
When the QV is less than 1t%, few passages are formed and gas dissipation does not occur smoothly, and when it exceeds 30wt%,
The amount of drying oil that is not retained by the fibrils increases, and the density of the carbon plate decreases.

In addition, the amount of phenolic resin is 1
A preferable range is 60 to 160 parts by weight per 00 parts by weight. When the amount of phenolic resin is 60 parts by weight, the density of the passages formed by the cellulose containing the drying oil becomes too high and does not disappear during carbonization shrinkage, resulting in clouding. It is thought that the density of the passages becomes low, making it easier for bubbles and cracks to occur.

Next, the present invention will be specifically explained with reference to experimental examples.

[Experimental Example] Kraft paper, tung oil and phenol resin (manufactured by Showa Kobunshi Co., Ltd., trade name BXL274) were used as raw materials.

First, kraft paper was placed in a mixer, water was added and stirred to loosen the cellulose fibers to form a slurry, and this slurry was dried in an oven at 120°C to obtain standard raw material cellulose.

Spray tung oil evenly onto this standard raw material cellulose using a sprayer. ■Cell L containing various 11N tung oil]-
I created a su.

Cellulose containing various amounts of tung oil obtained in this manner was combined with various 'X'EIi phenolic resins using a 3J pressure kneader (Co., Ltd.).
(manufactured by Shokude Seisakusho) for 15 minutes at room temperature under a pressure of 1 Kg/ci. After preheating this mixture at 100°C for 1 hour, it was filled into a 100° square mold and heated to 160°C.
, 30 kg/mouth for 10 minutes to produce a 5# thick green cedar board.

This 41: molded plate was sandwiched between two black T;) plates and fired and carbonized at 900° C. in a non-oxidizing atmosphere to produce a glassy carbon plate, and various observations and measurements were performed. Table 1 shows the respective formulations and the results of observations and measurements.

As is clear from Table 1, in order to make a high-quality glassy carbon treatment, the amount of tung oil in the cellulose containing tung oil should be in the range of 10 to 3 Qwt%, and the proportion of phenolic resin should be 11
is 60 to 10@sx parts of tung oil-containing cellulose.
A range of 160 parts by weight is preferred.

Furthermore, almost the same results as in Table 1 were obtained when linseed was used instead of tung oil and when tung oil modified phenolic resin was used instead of ordinary phenolic resin.

[Effects of the Invention] As described above, the method of the present invention can efficiently obtain a high-quality thick glass-like carbon plate with a thickness of 2 or more, which has been difficult in the past. This is an excellent method that can be expected to expand the range.

Claims (1)

[Claims] A glass characterized in that cellulose fibers containing a drying oil and a phenolic resin are mixed, and the resulting formed body obtained by shaping the mixture is subjected to firing carbonization treatment at a temperature of 800° C. or higher in a non-oxidizing atmosphere. A method for manufacturing a shaped carbon molded plate.