JPH11116648A - Production of spherical phenol resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject resin capable of controlling particle diameter when reacted without passing through a specific apparatus and troublesome process by adding as suspension stabilizer to a reaction system and reacting phenols with aldehydes in the presence of a specific catalyst combinedly used. SOLUTION: (D) A suspension stabilizer (e.g. polyvinyl alcohol or hydroxyethyl cellulose) is added to a reaction system and (A) phenols (e.g. phenol, cresol, xylenol or catechol) are reacted with (B) aldehydes (e.g. formaldehyde or benzaldehyde) under heating in the presence of (C) a catalyst producing a water-soluble resin [e.g. hydroxide of an alkaline (earth) metal or triethylamine] and a catalyst producing a water-insoluble resin (e.g. an amino compound other than tertiary amines) which is combinedly used to provide the objective spherical phenol resin. A material obtained by carbonizing the spherical phenol resin can be utilized as a raw material for activated carbon and electrode materials.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for obtaining a spherical phenolic resin without mechanical pulverization or particle size adjustment, and furthermore, it is used as a raw material for an activated carbon or an electrode material by carbonizing the same. The present invention relates to a method for producing a spherical phenol resin suitable for use in the present invention.

[0002]

2. Description of the Related Art A phenol resin is a resin having characteristics such as high heat resistance and high flame retardancy, and thus is widely used as a general-purpose resin such as a molding material and a binder of a fiber-reinforced plastic. Also, it is used as a carbon source for various carbon materials for reasons such as a high residual coal ratio, high purity, and an improvement in working environment.

[0003] Among these carbon materials, the fields in which particulate carbon materials are used include activated carbon used for gas adsorption and water purifiers, negative electrode materials for lithium ion secondary batteries, and electric double layer electrode materials. , And the like. Depending on the application, those requiring a particle size of 1000 μm or more, 20 μm
Some require a particle size of less than m. Conventionally, in order to produce a particulate carbon material used in the above fields, steps such as curing, pulverizing, carbonizing, and re-pulverizing a phenol resin are required.

[0004] Among these steps, in order to produce carbide having a sharp particle size distribution, a further classification step is required. Further, when producing a carbide having a large particle size, a large amount of non-reproducible fine particles are simultaneously generated in the pulverization process.
Furthermore, in the pulverization process, the shape of the particulate carbon material cannot be pulverized into a spherical shape or a shape without corners and swarfs, which affects the density of the carbon molded product, and the corners and swarfs are disintegrated during the formation of the carbon molded product, generating fine powder. There is a risk that the working environment will deteriorate and the characteristics of the final product will deteriorate. As a means for solving the above problem, there is a method of evaporating the solvent by spray-drying a phenol resin varnish dissolved in a solvent to obtain a granular resin. I will.

Further, a method has been proposed in which a granular resin is previously produced by a solution polymerization method at the stage of producing the resin.
Regarding the novolak resin, JP-A-4-159320 discloses a method in which a novolak resin and an aldehyde are mixed with an aqueous medium in the presence of polyvinyl alcohol having a molecular weight of 5,000 to 120,000 and a saponification degree of 96% or more, and ammonia or hexamethylenetetramine. It is disclosed that a spherical phenol resin can be obtained by reacting in a solution. However, this method is disadvantageous in cost because synthesis and spheroidization of a novolak resin and extra steps are required. JP-A-57-177001 discloses a method for producing a fine-particle phenol resin by reacting a phenol with a large excess of formalin under an acidic catalyst. However, in this method, a large excess of formalin and hydrochloric acid is used, which causes a problem of wastewater treatment after the reaction.

As disclosed in JP-A-61-258819, a phenol resin is dissolved again in phenol,
There is also a method of producing a phenol resin again by adding formalin, but the yield to phenol is low, which is disadvantageous in production cost. As disclosed in JP-A-52-141893, there is a method of curing a spherical phenol resin of resol for the purpose of producing a spherical cured product. This method uses hexamine as a catalyst for the purpose of producing a spherical phenolic resin, but requires a large amount of water to form a spherical shape. Further, this method cannot make a spherical phenol resin into a good spherical cured product.

[0007]

As described above, various methods for producing a granular phenolic resin composition have been disclosed, but each has problems such as particle size, production cost, wastewater treatment, and yield. . The present invention produces spherical phenolic resins having various particle size distributions without using special equipment and complicated processes, and without using expensive raw materials, and then uses the cured product such as activated carbon or battery electrode material. The aim is to provide carbides that can be used in the field.

[0008]

Means for Solving the Problems In order to achieve the above object, the present inventors have made intensive studies and found that phenols and aldehydes were dissolved in water or an organic solvent or a mixed solvent of water and an organic solvent. In a method for producing a spherical phenolic resin in which a kind and a catalyst for producing a water-soluble resin and a catalyst for producing a water-insoluble resin are reacted together, a suspension stabilizer is added and reacted by heating. It has been found that a nitrogen-containing spherical phenol resin having a predetermined particle size within a particle size of 0.1 to 2000 μm is obtained. That is,
It is characterized by producing a nitrogen-containing spherical phenol resin whose particle size can be adjusted from a small particle size to a large particle size during the reaction.

The catalyst for forming the water-soluble resin used in the present invention includes hydroxides, oxides and carbonates of alkali metals such as sodium, potassium and lithium, and alkaline earths such as barium, calcium and magnesium. It is a hydroxide such as a metal, an oxide, a carbonate or the like, triethylamine, or the like, and has many methylol groups and is a catalyst for producing a highly polar phenol resin. Further, the catalyst for producing the water-insoluble resin is an amino compound other than tertiary amines such as ammonia, DBU, and hexamine. These are nitrogen-containing catalysts, and are relatively high in polymer and highly nonpolar It is a catalyst that produces phenolic resin. The proportion used in combination is not particularly limited, and the amount of the catalyst for producing the water-soluble resin may be the amount used in a usual resol reaction. For example, about 1 to 5% by weight based on phenol is preferable.

The catalyst for forming the water-insoluble resin is 0.01 to 30% by weight, preferably 1 to 20% by weight, based on phenol. If the amount is less than 0.01% by weight, a spherical phenol resin having a large particle size cannot be obtained. If the amount is more than 30% by weight, the effect on the reaction is not changed, and the amount of addition is excessive.

The phenols used in the present invention include phenol, o-, m- or p-cresol, xylenol, catechol, resorcin, alkylphenols, bisphenols, etc., and these may be used alone or in combination of two or more. They may be used as such and are not particularly limited to these. Examples of the aldehydes include formaldehyde, paraformaldehyde, benzaldehyde, and the like, or a substance serving as a source of these aldehydes, or a solution of these aldehydes. Good and not particularly limited to these. The reaction molar ratio of formaldehyde / phenol is 0.85 to 2.50.
The degree is preferred.

As the reaction solvent, water or an organic solvent or a mixed solvent of water and an organic solvent is used in order to improve the solubility of the reactants in the initial reaction. The organic solvent used here is, for example, alcohols, ketones, etc., and as the alcohols, methanol, ethanol,
Examples of ketones include propyl alcohol, ethylene glycol, diethylene glycol, trimethylene glycol and the like, and acetone, methyl ethyl ketone and the like. After the reaction, the reaction solvent can be separated and removed from the spherical phenol resin, and can be removed by air drying, heating drying, or vacuum drying.

Examples of suspension stabilizers include polyvinyl alcohol, hydroxyethyl cellulose, carboxymethyl cellulose, soluble starch, agar, acacia, gum arabic, hydroxyalkyl guar gum, ethylene oxide, propylene oxide, polyacrylamide and the like. The mechanism of forming the spherical cured product is that the suspension stabilizer covers the phenol resin and forms micelles to form particles. The control of the particle size is determined by the concentration of the suspension stabilizer. When the concentration of the suspension stabilizer is increased, spherical particles having a small particle size are obtained, and when the concentration is low, spherical particles having a large particle size are obtained.

The phenolic resin obtained by the present invention may be treated with other polymerizations such as pigments, dyes, lubricants, antistatic agents, antioxidants, abrasives, graphite, etc., as long as the polymerizability and physical properties are not impaired. Can be added and introduced.

[0015]

The present invention will be described below with reference to examples. However, the present invention is not limited by the examples. Further, “parts” and “%” shown in Examples and Comparative Examples are all “parts by weight” and “% by weight”.

Example 1 700 parts of phenol and 100% aqueous solution of 35% formaldehyde were placed in a 3 L three-necked flask.
0 parts, 350 parts of water, 20 parts of triethylamine, and 0.7 part of polyvinyl alcohol (Kurarepovar PVA117, degree of saponification 98%, degree of polymerization 1700), and 100 parts.
Heated to ° C. 80 minutes after the temperature reached 100 ° C., 35 parts of hexamine was added, and the reaction was further performed at 100 ° C. for 4 hours. Thereafter, the contents were washed three times with 60 ° C. water, filtered,
By drying at 0 ° C., the spherical phenol resin is
0 parts were obtained.

Example 2 700 parts of phenol and 100% of a 35% aqueous formaldehyde solution were placed in a 3 L three-necked flask.
0 parts, 350 parts of water, 20 parts of triethylamine, and 3.5 parts of gum arabic were added and heated to 100 ° C. 100
40 minutes after the temperature reached 35 ° C., 35 parts of hexamine was added,
The reaction was carried out at 100 ° C. for another 4 hours. Then 3 times with 60 ° C water
The contents were washed with water, filtered and dried at 80 ° C. to obtain 800 parts of a spherical phenol resin.

Example 3 700 parts of phenol and 100% aqueous 35% formaldehyde solution were placed in a 3 L three-necked flask.
0 parts, 700 parts of water, 20 parts of triethylamine, and 0.7 part of gutte rubber were added and heated to 100 ° C. 100
80 minutes after the temperature reached ℃, 35 parts of hexamine was added,
The reaction was carried out at 100 ° C. for another 4 hours. Then 3 times with 60 ° C water
The contents were washed with water, filtered and dried at 80 ° C. to obtain 800 parts of a spherical phenol resin.

Example 4 700 parts of phenol and 100% aqueous 35% formaldehyde solution were placed in a 3 L three-necked flask.
0 parts, 350 parts of water, 7 parts of sodium hydroxide, and 0.7 part of polyvinyl alcohol (Kurarepovar PVA117, degree of saponification 98%, degree of polymerization 1700), and 100 ° C.
Until heated. 80 minutes after the temperature reached 100 ° C., 35 parts of hexamine was added, and the reaction was further performed at 100 ° C. for 4 hours.
Thereafter, the content was washed with water at 60 ° C. three times, filtered, and dried at 80 ° C.
To obtain 800 parts of a spherical phenol resin.

(Comparative Example 1) 700 parts of phenol and 100% aqueous solution of 35% formaldehyde were placed in a 3 L three-necked flask.
0 parts, water 350 parts, hexamine 35 parts, and polyvinyl alcohol (Kurarepovar PVA117, saponification degree 9
3.5 parts of 8% and a polymerization degree of 1700) were added and heated to 100 ° C. It reacted at 100 degreeC after heating for 5 hours.

The particle size distribution of the spherical phenolic resin obtained in each of Examples and Comparative Examples was measured. Table 1. Particle size distribution measurement of spherical phenol resin ───────────────────────────── Particle size [μm] 212 or less 212 to 1000 1000 or more ──実 施 Example 1 10% 36% 54% Example 2 5% 20% 75% Example 3 20% 57% 23% Example 4 10% 30% 60% Comparative Example 1 The whole reaction system gelled. ─

[0022]

According to the present invention, a spherical phenol resin having a small particle size to a large particle size can be obtained at low cost without performing complicated steps. In addition, by changing the degree of reactivity of the obtained phenolic resin, it is possible to arbitrarily produce from a heat-meltable one to a hardened one with a spherical shape,
It is useful as a raw material for activated carbon and electrode materials.

Claims (3)

[Claims] 1. A method for producing a spherical phenol resin in which a phenol and an aldehyde are reacted under a combined use of a catalyst for forming a water-soluble resin and a catalyst for forming a non-water-soluble resin, wherein the phenol and the aldehyde are suspended in a reaction system. A method for producing a nitrogen-containing spherical phenolic resin, which comprises adding an agent and heating to react. 2. The catalyst for producing a water-soluble resin is one or more selected from hydroxides, oxides or carbonates of alkali metals or alkaline earth metals, and triethylamine. A method for producing a spherical phenol resin. 3. The method for producing a spherical phenolic resin according to claim 1, wherein the catalyst for forming the water-insoluble resin is an amino compound other than a tertiary amine.