JPS6348319A - Production of graphite/phenolic resin particle - Google Patents

Abstract

PURPOSE:To obtain graphite/phenolic resin particles inexpensively at a low energy consumption by few steps, by reacting a phenol with a formaldehyde in the presence of a catalyst while mixing the reactants with graphite powder. CONSTITUTION:Graphite/phenolic resin particles are obtained by reacting a phenol with a formaldehyde in the presence of a catalyst while mixing the reactants with graphite powder. As the reaction catalyst, a basic substance which can form an -NCH2 bond between benzene nuclei of the phenol (e.g., hexamethylenetetramine) can be used. The mixing ratio of the phenol to the formaldehyde is preferably such that the molar ratio of the phenol to the formaldehyde may fall within the range of 1:1-1:3.5. The amount of the graphite powder added is desirably clesigned so that the weight ratio of the phenol to the graphite may fall within the range 100:5-10:3000.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing a mixed granular material of graphite and phenolic resin.

[Prior Art] A mixture of phenolic resin and graphite is used as a molding material for refractories, casting materials, and sliding members such as grindstones, brake linings, and bearings. When graphite is mixed with the 7-enol resin and used in this way, it is common to mix the 7-enol resin with graphite and granulate it to use it as granules.

In producing such mixed particles of graphite and 7-dinol resin, it has conventionally been generally carried out as follows. First, phenols and formaldehydes are reacted in the presence of a reaction catalyst. Then, graphite particles are added to this 727-al resin, kneaded in a kneader, etc., extruded, dried, and then pulverized. In this way, graphite/phenol BIN granules, which are mixed granules of graphite and 727-l resin, are obtained.

[Problems to be Solved by the Invention] However, when producing graphite/phenolic resin granules using such a method, the process of producing phenolic resin and dehydration, and mixing the 7-el resin and graphite are necessary. Various processes are required, including a kneading process, extrusion and drying of the mixture, and further pulverization and granulation processes, which increases the number of manufacturing steps and requires processes that consume large amounts of energy such as dehydration, kneading, and pulverization. Therefore, there are problems such as increased manufacturing cost.

The present invention has been made in view of the above points, and is a graphite/phenol resin granular mixture of graphite and 7-enol resin that can be produced at low cost with less energy consumption and in fewer steps. The object of the present invention is to provide a method for producing resin granules.

[Structure of the invention] Steps for performing (1) The method for producing graphite/phenol resin granules according to the present invention includes mixing phenols and formaldehydes with graphite powder in the presence of a catalyst. The VF characteristic is to cause the reaction to occur while the reaction occurs, and the present invention will be described in detail below.

In the present invention, phenols mean 7-ethyl and phenol derivatives, and include, in addition to phenol, trifunctional ones such as l-cresol, resorcinol, and 3,5-xylenol, and bisphenol A1 dihydrocarbons. Tetrafunctional ones such as quizinophenylmethane, 0
-cresol, p-cresol. Examples include difunctional 〇- or p-substituted 7-functional alcohols such as p4er butylphenol, p-phenylphenol, p-cumylphenol, p-nonylphenol, 2.4 or 2.61 silenol, etc. Furthermore, halogenated 7-eryls substituted with chlorine or bromine can also be used.

Of course, in addition to selecting and using one type from these, formalin, which is in the form of an aqueous solution, is most suitable as a double formaldehyde, but it is also possible to use a form such as paraformaldehyde, or a part or large amount of formaldehyde. It can be used by replacing the moiety with furfural or furfuryl alcohol. Furthermore, as a reaction catalyst, basic substances that generate -NC82 bonds between the benzene nuclei of heptanenols, such as hexamethylenetetramine, ammonia, methylamine, dimethylamine, ethylenediamine, monoethanolamine, etc. Ill, secondary amines, etc. can be used. In addition, in combination with these, hydroxides of alkali metals and alkaline earth metals, and 7
A basic catalyst that is commonly used in the synthesis of 17-ru(8) can also be used.

These 7 ethanols, formaldehydes, and a reaction catalyst are placed in a reaction vessel such as a reaction pot, and the phenols and formaldehyde are mixed together. In the presence of this graphite powder, the 7 enols and formaldehyde are combined. make the reaction take place.

As the graphite powder, any carbonaceous powder can be generally used, such as natural graphite, artificial graphite, carbon black, coke powder, charcoal powder, etc., and these can be used singly or in combination. Can be used in combination. Although the particle size of the graphite head powder is not particularly limited, it is preferable that the average particle size is 20 μm or less. Furthermore, the blending ratio of phenols and formaldehydes is preferably set so that the molar ratio of phenols and formaldehydes is in the range of 1:1 to 1:3.5, and the blending amount of graphite powder is It is preferable to set the weight ratio of 7 alcohols and graphite to be in the range of 100:5 to 100:3000.

Furthermore, when phenols and formaldehydes are reacted in the presence of graphite powder as described above, this reaction is carried out in the presence of at least enough water to stir the reaction system. If we define this water as primary water, - large water means the water that is present in the reaction system at the start of the reaction, and is included in the formulation ingredients such as formalin in addition to the water that is added at the start of the reaction. Also includes water. In this way, when phenols and formaldehydes are reacted in the presence of graphite powder while stirring in large water, the reaction system is viscous mayonnaise-like at the beginning of the reaction and becomes fluid as it is stirred. However, as the reaction progresses, the condensation reaction product of phenol and formaldehyde containing graphite powder gradually begins to separate from the water in the system, and black particles consisting of phenol resin and graphite powder are produced by the reaction. suddenly becomes dispersed throughout the reaction vessel.

Although it is not clear why particles made of phenolic resin and graphite powder suddenly become dispersed in this way,
Dogs are expected. In other words, graphite has a low affinity for water and is not dispersed in water at the initial stage of the reaction, but graphite is an intercalated compound with wood carbon rings connected in a layered manner and has a high adsorption property between the eyebrows, and phenols and aldehydes The phenolic resin produced as the reaction progresses with the phenolic resin is adsorbed between the layers of the graphite, and the graphite is dispersed as a mixture with the phenolic resin. It is thought that the black particles are formed by agglomerates of .

After the mixed black particles of graphite powder and 7-enol resin are dispersed and produced in this way, the reaction of 72/-L0i fat is further advanced to the desired degree, and after cooling, stirring is stopped. The black particles are precipitated and separated from the water.

These black particles are in the form of fine spherical particles, and can be easily separated by taking them out of the reaction vessel and filtering them. By drying this, graphite/phenol resin granules can be obtained. Here, the graphite/phenol resin particles easily separate from water and precipitate.
By filtration, the solid content can be easily separated from water without requiring large amounts of thermal energy as in conventional dehydration. In addition, when mixing phenol resin and graphite powder, dispersion mixing of the phenol and formaldehyde is performed during the reaction between the two, which is different from the conventional method.
J3! There is no need to perform the manufacturing process and the kneading and mixing of the phenol resin and graphite powder in separate processes, which reduces the number of man-hours and does not require large amounts of energy such as cross-wires. Furthermore, the granulation of phenolic resin granules will be done during the phenolic resin preparation reaction, and as in the past, 7-enol resin and graphite are kneaded, extruded, dried, and then pulverized. It does not require such steps, reduces the number of man-hours, and does not require large amounts of energy such as extrusion or crushing. The graphite/phenol resin granules obtained in this way have a spherical shape because they are produced by agglomeration of graphite powder and phenol resin in water, and have poor fluidity. It is excellent in that it can be easily handled by airflow conveying through a duct from a storage tank to a molding device, etc. It is generally desirable that the particle size of the graphite/phenol resin granules is about 311a1 or less.

Here, the amount of primary water in the above reaction system and the amount of graphite produced
There is an extremely high correlation between the shape of phenolic resin granules, especially the size of the particles. That is, when the amount of secondary water is small, particles with a large particle size are obtained, and when the amount of secondary water is large, particles with a small particle size are obtained, and this relationship is linear. Therefore, by adjusting the amount of primary water in the reaction system, graphite can be made to any desired particle size.
It will be possible to produce phenolic resin granules. At this time, in order to obtain graphite/phenolic resin granules with a large particle size, the amount of primary water in the reaction system is reduced (then, after the mixed particles of graphite powder and phenolic resin are dispersed, During the reaction of the 727-ru resin, particles adhere to each other and the size of the particles becomes even larger, which may cause variations in particle size or deformation of the particle shape. In this case, it is preferable to mix and add water to the reaction system after the mixed particles of graphite powder and phenol resin are dispersed to prevent the particles from adhering to each other. If this water is defined as secondary water, the secondary water can be added to the reaction system at any time after the mixed particles of graphite powder and 72/-L tree dish are dispersed and before the stirring is stopped. It is also possible to add a protective colloid to the secondary water in addition to adding it to the reaction system.

By using a protective colloid, it is possible to improve the dispersibility of the particles, reliably prevent the particles from adhering to each other, and it is possible to make the diameters of the particles of the graphite/phenol resin particles uniform. Gum arabic as a protective colloid,
Hydrophilic materials such as rhododendron, hydroxyalkyl, guar rubber, and polyvinyl alcohol, and hydrophobic materials such as calcium chloride, magnesium heptafluoride, and strontium heptafluoride can be used. Of course, the protective colloid can be added to the reaction system separately from the secondary water, but the timing of addition is set after the mixed particles of graphite powder and phenol resin are dispersed and before the stirring is stopped. If the addition time is earlier than this, the graphite powder and the 72/- resin will be dispersed within minutes! There is a possibility that the graphite/phenol resin granules cannot be obtained. Furthermore, if a hydrophobic protective colloid is used, the surface of the generated graphite/phenolic resin particles can be coated with a hydrophobic film, and blocking of the graphite/phenolic resin particles can be prevented. It turns out.

When graphite/phenol resin granules are used as a molding material, the reaction between phenols and formaldehyde is stopped before they reach a three-dimensional crosslinking state, and they are produced as thermally reactive materials. When used as a compound, the reaction between phenols and formaldehyde may be allowed to proceed to a three-dimensional crosslinked state to produce a product that is insoluble in major solvents and infusible under heat.

Next, the present invention will be further explained by examples.

In a reaction vessel, 500 parts by weight of flaky graphite with an average particle size of 5 μ, 397.5 parts by weight of phenol, 466 parts by weight of 37% formalin, 38.2 parts by weight of hexamethylenetetramine as a reaction catalyst, Furthermore, water was added to each of the 385-layer plates, and this was heated to 85°C while stirring.
Heating was maintained at 5°C. Initially, the contents were viscous mayonnaise-like and fluid with stirring, but as the reaction progressed, the reaction product of 7 enol and formaldehyde, including graphite, gradually began to separate from the water in the reaction system. 85
About 15 minutes after reaching the temperature, black particles consisting of graphite and 7-el resin suddenly became dispersed throughout the reaction vessel. After this, after further stirring and heating at 85°C for 60 minutes, the contents of the reaction vessel were cooled to below 40°C, and when stirring was stopped, the black particulate matter settled and was separated from water. .

Next, the black particulate matter was taken out from the reaction vessel, washed with water, and then put into ill! The mixture was then separated from water and dried using a fluidized bed dryer at a hot air temperature of 55°C and a residence time of 5 o'clock to obtain graphite/phenol resin granules having a thermosetting function.

The properties of this X@lead/phenol resin granule were as follows.

・Particle shape: Size 60-450μ (80-2
00μ is 76%) Almost spherical particles / Resin content: 48.1% ・Residual moisture = 0.7% by weight Husband (1) The amount of water charged into the reaction vessel was increased from 385 parts by weight to 600 parts by weight. Graphite/phenol resin granules having a thermosetting function were obtained in the same manner as in Example 1 except for the following changes.

The properties of this graphite/phenol resin granule were as follows.

・Particle shape: Spherical particles with a size of 75 to 250μ ・Resin content: 48.0% by weight ・Residual moisture: 0.5% by weight , 397.5 parts by weight of 7 ether, 466 parts by weight of 37% formalin, 38.2 parts by weight of hexamethylenetetramine, and 250 parts by weight of water were prepared in the same manner as in Example 1. When the reaction was carried out and black particles consisting of graphite and phenol υ (N) were dispersed throughout the reaction vessel, the temperature was increased to 1200°C, which was further heated to 60°C.
Add part by weight of water as secondary water and bring the temperature of the contents to 8.
The reaction was maintained at 5° C. for 60 minutes. The following graphite/phenol has thermosetting properties in the same manner as in Example 1! (Obtained fat granules.

The properties of this graphite/7㎱/l fallen fat granules were as follows.

・Particle shape: Size 150-1000μ (21 of these
Spherical particles of 0 to 840μ (78%) Resin content: 48.6% by weight ・Residual moisture 20.8% by weight Add 250 parts by weight of water to the reaction vessel before starting the reaction. Graphite/phenol resin granules having a thermosetting function were obtained in the same manner as in Example 3, except that the amount was changed from 150 parts by weight.

The properties of this graphite/phenol uI fat granule were as follows.

・Particle shape: Size 420-1100μ (60 of these
Spherical particles with 0 to 1000 μm (84%) Resin content: 48.6% by weight ・Residual moisture: 1.0% by weight Add scaly graphite with an average particle size of 5 μm to a reaction vessel. 500 parts by weight, 397.5 parts by weight of phenol, 234.4 parts by weight of 92% formaldehyde, 8 parts by weight of 25% ammonia.
0 parts by weight, 15 parts by weight of 25% caustic soda water, and 1400 parts by weight of water! The reaction was carried out in the same manner as in Example 1, and 15 minutes after the black particles consisting of graphite and 72/-l resin were dispersed throughout the reaction vessel, the water was removed. Next, 500 parts by weight of water was added, and the temperature of the contents was maintained at 85° C. to continue the reaction for 60 minutes. Graphite/phenol resin granules having a thermosetting function were obtained in the same manner as in Example 1.

The properties of this graphite/7-enol resin granules were as follows.

・Particle shape: Size 50-150μ (75-1
Spherical particles of 50 μm (92%) Resin content: S O, O weight % ・Residual moisture 20.5 weight % Salmon 1 1200 parts by weight of secondary water and 5 parts by weight of gum arabic as a protective colloid. Graphite/phenol resin granules having a thermosetting function were obtained in the same manner as in Example 3, except that the graphite/phenol resin particles were used after being dissolved.

The properties of the graphite/7E resin granules were as follows.

・Particle shape: Large - yioo ~ 600μ (15 of these
0-250μ (94%) Resin content: 48.5% by weight Residual moisture: 0.5% by weight: 1LLL Potassium heptafluoride 11 as a protective colloid in 1200 parts by weight of secondary water Graphite/phenol 84 fat granules having a thermosetting function were obtained in the same manner as in Example 3, except that 0.6 parts by weight and 16.8 parts by weight of calcium chloride were dissolved and used.

The properties of this graphite/phenol resin granule were as follows.

・Particle shape: Size 100 to 500μ (of which 15
0 to 250μ (95%) Resin content: 48.6% Residual moisture: o, sl amount% and 19 The reaction proceeds in the same manner as in Example 3 to obtain secondary water. After adding, the reaction was further allowed to proceed at 85°C for 120 minutes,
Then, the temperature of the contents of the reaction vessel was raised at a rate of 1'C/1 minute, and the reaction was carried out under reflux for 300 minutes. Next, in accordance with Example 1, the black particulate matter in the reaction vessel was taken out, filtered through illumination, dried, and then heated for 180 minutes in a thermostat kept at 200"C to form a hardened graphite. Phenol resin granules were obtained.

The properties of this graphite/phenol resin granule were as follows.

・Particle shape: Size 150-1000μ (21 of these
Spherical particles with 0 to 840μ (78%) Properties: Insoluble in organic solvents and infusible to heat [Effects of the invention] As described above, according to the present invention, phenols and aldehydes are combined in the presence of a catalyst. By reacting the graphite powder while mixing it with the graphite powder described below, it is possible to disperse and generate a granular material in which the graphite powder and the 7-enol resin are aggregated in the reaction system, and this granular material can be filtered from water. Graphite/phenol resin granules can be obtained by separating the graphite/phenol resin granules, which does not require large thermal energy like conventional dehydration (manufacturing graphite/phenolic resin granules). In addition, the mixing of the 7-el resin and the graphite powder is done during the reaction between the phenol and the formaldehyde, and the preparation of the phenol 84N and the mixing of the phenol resin as in the past. There is no need to perform cross-mixing of graphite and graphite powder in a separate process, which reduces the number of man-hours and does not require large amounts of energy such as kneading.Furthermore, it is possible to granulate graphite and phenolic resin particles. This is done during the preparation reaction of phenolic resin, and does not require the conventional process of kneading 72/-l resin and graphite, extruding, drying, and further pulverizing. This can reduce the number of man-hours and does not require large amounts of energy such as extrusion or crushing.Therefore, according to the present invention, the amount of graphite/phenol FBI fat granules in which graphite and 7-enol resin are mixed can be reduced. It is a process that consumes less energy and can be manufactured at low cost.

Claims (9)

[Claims] (1) A method for producing graphite/phenolic resin granules, which comprises reacting phenols and formaldehyde in the presence of a catalyst while mixing them with graphite powder. (2) The method for producing graphite/phenolic resin granules according to claim 1, wherein the reaction is carried out in the presence of at least an amount of water sufficient to stir the reaction system. (3) Graphite/phenol according to claim 1 or 2, characterized in that water is added to the reaction system after the graphite powder and the reaction product are aggregated and granulated. Method for producing resin granules. (4) The method for producing graphite/phenolic resin granules according to claim 3, characterized in that a protective colloid is mixed with water and added to the reaction system. (5) The molar ratio of phenols and formaldehyde is 1
5. The method for producing graphite/phenol resin granules according to any one of claims 1 to 4, characterized in that the ratio is from 1:1 to 1:3.5. (6) Weight ratio of phenols and graphites is 100:5 to 1
The method for producing graphite/phenolic resin granules according to any one of claims 1 to 5, characterized in that the ratio is 0.00 to 3000. (7) The method for producing graphite/phenol resin granules according to any one of claims 1 to 6, wherein the reaction catalyst is a basic catalyst. (8) The graphite/phenolic resin granules according to any one of claims 1 to 7, wherein the reaction is stopped in a state where the graphite/phenolic resin granules have thermal reactivity. manufacturing method. (9) The reaction is continued until the graphite/phenolic resin particles become insoluble and insoluble in the organic solvent. A method for producing phenolic resin granules.