JP2006104239A - Method for producing novolak phenolic resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a novolak phenolic resin at a production cost which can be reduced not only because it can produce a novolak phenolic resin having controlled contents of phenolic monomers and phenolic dimers and a controlled polydispersity index in a high yield but also because it includes an efficient washing step. <P>SOLUTION: The method comprises the 1st step of subjecting a phenol and an aldehyde to a heterogeneous system reaction in the presence of a phosphoric acid and the 2nd step of separating the reaction mixture into a water layer and an organic layer after the 1st step, removing the water layer, and bringing the organic layer into contact with an ion exchange resin. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing a novolac type phenolic resin.

  The present applicant has developed a novolak-type phenol resin in which the content and dispersion ratio of phenolic monomers and phenolic dimers are controlled by heterogeneous reaction of phenols and aldehydes in the presence of phosphoric acids. A method for producing a novolac-type phenolic resin that can be obtained in a yield is proposed (Patent Documents 1 and 2).

  In Patent Documents 1 and 2, in the system after the completion of the reaction, for example, a water-insoluble organic solvent such as methyl ethyl ketone or methyl isobutyl ketone is added and mixed to dissolve the condensate, and then allowed to stand to leave an organic layer and an aqueous layer. After removing most of phosphoric acids by removing the aqueous layer, the phosphoric acid remaining in the organic layer is removed by washing with water.

International Publication No. 03/042267 Pamphlet International Publication No. 2004/020492 Pamphlet

  The present invention not only can obtain a high yield of novolak-type phenolic resin in which the content and dispersion ratio of phenolic monomers and phenolic dimers are controlled, but also makes the washing process more efficient and reduces production costs. It aims at providing the manufacturing method of a novolak-type phenol resin.

  That is, the method for producing a novolac type phenolic resin of the present invention comprises a first step in which phenols and aldehydes are reacted in a heterogeneous system in the presence of phosphoric acids, and after the first step, an aqueous layer and an organic layer are formed. And a second step of separating the aqueous layer and bringing the organic layer into contact with an ion exchange resin.

  ADVANTAGE OF THE INVENTION According to this invention, the novolak-type phenol resin by which content and dispersion ratio of the phenolic monomer and phenolic dimer were controlled can be obtained with a high yield.

  Further, by removing the residual phosphoric acid in the organic layer with the ion exchange resin, the efficiency of the cleaning process can be improved, the waste liquid can be reduced, and the resin is not colored in the cleaning process.

  In the first step of the present invention, a novolac type phenol resin is obtained by subjecting phenols and aldehydes to a condensation reaction in a heterogeneous system while stirring and mixing in the presence of phosphoric acids and preferably a reaction auxiliary solvent.

  In the first step, the phenols used as a reaction raw material include, for example, phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, 2,3- Xylenol, 2,5-xylenol, 3,5-xylenol, 3,4-xylenol, 2-propylphenol, 2-isopropylphenol, 3-propylphenol, 3-isopropylphenol, 4-propylphenol, 4-isopropylphenol, 2-sec-butylphenol, 2-tert-butylphenol, 3-sec-butylphenol, 3-tert-butylphenol, 4-sec-butylphenol, 4-tert-butylphenol, 2-cyclohexylphenol, 3-cyclo Xylphenol, 4-cyclohexylphenol, 2-nonylphenol, 3-nonylphenol, 4-nonylphenol, 2-dodecylphenol, 3-dodecylphenol, 4-dodecylphenol, 2-octadecylphenol, 3-octadecylphenol, 4-octadecylphenol, Alkylphenols such as 2-isopropyl-5-methylphenol, 2-tert-butyl-4-methylphenol, 3-methyl-6-tert-butylphenol, 2,3,5-trimethylphenol, 2,3,5-triethylphenol O-isopropenyl phenol, m-isopropenyl phenol, p-isopropenyl phenol, 2-methyl-4-isopropenyl phenol, 2-ethyl-4-isopropenyl phenol Any isopropenylphenol, phenylphenol such as 2-phenylphenol, 3-phenylphenol, 4-phenylphenol, naphthylphenol such as 2-naphthylphenol, 3-naphthylphenol, 4-naphthylphenol, o-methoxyphenol , M-methoxyphenol, p-methoxyphenol, o-ethoxyphenol, m-ethoxyphenol, p-ethoxyphenol, o-propoxyphenol, m-propoxyphenol, alkoxyphenols such as p-propoxyphenol, bisphenol A, bisphenol F, bis (2-methylphenol) A, bis (2-methylphenol) F, bisphenol S, bisphenol E, bisphenol Z, 4,4′-dihydroxybiphenyl, Examples thereof include polyhydroxyphenols such as resorcinol, hydroquinone and pyrogallol, and naphthalenes such as α-naphthol, β-naphthol and dihydroxynaphthalene.

  Among these, particularly in the epoxy field, 2-phenylphenol, 2-tert-butylphenol, and 2-cyclohexylphenol are preferably used.

  The phenols are not limited to the above examples, and may be used alone or in combination of two or more.

  As a method for adding phenols, a method suitable for the purpose, such as a method in which the raw materials are added together with the raw materials or a method in which the phenols are added in a divided manner as the reaction proceeds, may be employed.

  Examples of aldehydes used as reaction raw materials in the first step include formaldehyde, formalin, paraformaldehyde, trioxane, acetaldehyde, paraaldehyde, propionaldehyde, parapropionaldehyde, benzaldehyde, salicylaldehyde, and the like. In addition, they may be used alone or in combination of two or more.

  As a method for adding aldehydes, a method suitable for the purpose, such as a method in which raw materials are added together with a raw material or a method in which the aldehydes are added in a divided manner as the reaction proceeds, may be employed.

  The compounding ratio (F / P) of phenols (P) and aldehydes (F) is not particularly limited, but is preferably 0.33 to 1.0, more preferably 0.6 to 1.0 on a molar basis. 0.97. If the blending ratio is less than 0.33, it may be difficult to reduce the content of components below the phenol dimer. Conversely, if it exceeds 1.0, unreacted aldehydes increase and production efficiency decreases. there's a possibility that.

  In the first step, phosphoric acids used as a reaction catalyst play an important role in forming a phase separation reaction (heterogeneous reaction) between phenols and aldehydes. Examples include, for example, polyphosphoric acid such as metaphosphoric acid, pyrophosphoric acid, orthophosphoric acid, triphosphoric acid, and tetraphosphoric acid, phosphoric anhydride, and mixtures thereof. Generally 75 mass% phosphoric acid, 89 mass% phosphoric acid, etc. are used.

  The blending amount of phosphoric acids is preferably 5 parts by mass or more with respect to 100 parts by mass of phenols, and the upper limit is not particularly limited, but considering reaction volume efficiency, safety, phase separation effect, etc. Preferably it is 20-200 mass parts, More preferably, it is 40-100 mass parts. When the blending amount is less than 5 parts by mass, the production of a high molecular weight component is promoted, while the low molecular weight component, particularly the phenolic dimer component, tends not to be reduced.

  As a method for adding phosphoric acids, a method suitable for the purpose, such as a method in which the raw materials are added together with a raw material or a method in which the phosphoric acid is added in a divided manner as the reaction proceeds, may be employed.

  In the first step, it is preferable to use a non-reactive oxygen-containing organic solvent as a reaction auxiliary solvent from the viewpoint of promoting the phase separation reaction. As the reaction auxiliary solvent, it is preferable to use at least one selected from the group consisting of alcohols, polyhydric alcohol ethers, cyclic ethers, polyhydric alcohol esters, ketones, and sulfoxides.

  Examples of alcohols include monohydric alcohols such as methanol, ethanol, and propanol, butanediol, pentanediol, hexanediol, ethylene glycol, propylene glycol, trimethylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, and tripropylene glycol. And dihydric alcohols such as polyethylene glycol and trihydric alcohols such as glycerin.

  Examples of the polyhydric alcohol ether include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monopentyl ether, ethylene glycol dimethyl ether, ethylene glycol methyl ethyl ether, ethylene glycol mono Examples include glycol ethers such as phenyl ether.

  Examples of the cyclic ethers include 1,3-dioxane and 1,4-dioxane. Examples of the polyhydric alcohol ester include glycol esters such as ethylene glycol acetate. Examples of ketones include Examples include acetone, methyl ethyl ketone, and methyl isobutyl ketone. Examples of the sulfoxide include dimethyl sulfoxide and diethyl sulfoxide.

  Among these, methanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol, polyethylene glycol, 1,4-dioxane and the like are particularly preferable.

  The reaction auxiliary solvent is not limited to these, and can be used as a solid as long as it has the above-mentioned characteristics and exhibits a liquid state at the time of the reaction. You may use the above together.

  Although it does not specifically limit as a compounding quantity of a reaction auxiliary solvent, Preferably it is 5-1000 mass parts with respect to 100 mass parts of phenols, More preferably, it is 10-500 mass parts. If the blending amount is less than 5 parts by mass, the effect of adding a solvent may not be recognized, and if it exceeds 1000 parts by mass, the productivity may decrease in terms of reaction rate and volumetric efficiency.

  As a method for adding the reaction auxiliary solvent, a method suitable for the purpose may be employed, such as a method in which the reaction auxiliary solvent is added together with the raw material or a method in which the reaction auxiliary solvent is added in a divided manner as the reaction proceeds.

  Further, by using a surfactant in the first step as necessary, the phase separation reaction can be promoted, the reaction time can be shortened, and the yield can be improved.

  Surfactants include soaps, alpha olefin sulfonates, alkyl benzene sulfonic acids and their salts, alkyl sulfate salts, alkyl ether sulfate salts, phenyl ether ester salts, polyoxyethylene alkyl ether sulfate salts, ether sulfonate salts. , Anionic surfactants such as ether carboxylates, polyoxyethylene alkylphenyl ethers, polyoxyalkylene alkyl ethers, polyoxyethylene styrenated phenol ethers, polyoxyethylene alkylamino ethers, polyethylene glycol aliphatic esters, aliphatic monoglycerides Sorbitan aliphatic ester, pentaerythritol aliphatic ester, polyoxyethylene polypropylene glycol, aliphatic alkylol amide, etc. Nonionic surface active agents, monoalkyl ammonium chloride, cationic surfactants such as amine acid salts.

  Although it does not specifically limit as a compounding quantity of surfactant, Preferably it is 0.5 mass part or more with respect to 100 mass parts of phenols used as a reaction raw material in a 1st process, More preferably, it is 1-10 mass. Part.

  In the first step, from the viewpoint of the phase separation effect, the water content in the system is preferably 40% by mass or less, preferably 20% by mass or less in advance before starting the reaction. From the viewpoint of reaction efficiency and phase separation effect, the reaction temperature is generally 40 ° C or higher, preferably 80 ° C or higher, and more preferably reflux temperature. The reaction time is determined in consideration of the reaction temperature, the amount of phosphoric acid, the water content of the reaction system, the condensation state of the product, etc., but is generally about 1 to 50 hours. The reaction environment is usually atmospheric pressure, but the reaction may be performed under pressure or under reduced pressure as long as the heterogeneous reaction characteristic of the present invention is maintained.

  In the first step, after completion of the reaction, it is better to add a water-insoluble organic solvent that works as a good solvent for the phenol resin to reduce the viscosity of the condensate (novolak type phenol resin) in the second step. This is convenient for improving the phosphoric acid removal efficiency in the ion exchange resin.

  Examples of the water-insoluble organic solvent that acts as a good solvent for the phenol resin include ketones, alcohols, ethers, and esters.

  Examples of the ketones include methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, diisopropyl ketone, diethyl ketone, ethyl-n-butyl ketone, cyclohexanone, di-n-propyl ketone, and methyl-n-amyl ketone.

  Examples of alcohols include n-butanol, isobutanol, 2-methyl-1-butanol, and the like. Alcohols that are freely mixed with water, such as isopropanol, ethanol, and methanol, are not suitable.

  Examples of ethers include anisole, diethyl ether, dibutyl ether, dipropyl ether and the like. Ethers that are freely mixed with water, such as dioxane and dimethyl ether, are not suitable.

  Examples of the esters include ethyl acetate, isobutyl acetate, isopropyl acetate and the like.

  Among these, ketones such as methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, and diethyl ketone are particularly preferable.

  The addition ratio of the water-insoluble organic solvent is not particularly limited, but is preferably 10 to 500 parts by mass, more preferably 30 to 300 parts by mass with respect to 100 parts by mass of the phenols. If the addition ratio is less than 10 parts by mass, the effect of reducing the viscosity may not be obtained.

  The present invention includes a second step of separating the aqueous layer and the organic layer after the first step, removing the aqueous layer, and bringing the organic layer into contact with an ion exchange resin.

  Specifically, after the first step, stirring and mixing are stopped and left to stand in an organic layer (including phenols and condensate) and an aqueous layer (including phosphoric acids and a reaction auxiliary solvent if added). Separate. Next, after removing the aqueous layer from the system, the phosphoric acids and the reaction auxiliary solvent are recovered, while the organic layer is brought into contact with the ion exchange resin to remove residual phosphoric acid, and then the residual water and added by vacuum concentration. In this case, the water-insoluble organic solvent that works as a good solvent for the phenol resin is completely removed.

  Typical methods for bringing the organic layer into contact with the ion exchange resin include a batch method and a column method. The batch method is a method in which an ion exchange resin is directly charged into an organic layer, and the organic layer and the ion exchange resin are brought into contact while stirring with a stirrer. The column method is a method in which a column having a predetermined size is filled with an ion exchange resin, and the organic layer is brought into contact with the ion exchange resin by passing or circulating through the column.

  As the ion exchange resin, an anion exchange resin into which a functional group having anion exchange ability is introduced is used. Anion exchange resins are classified into two types, strong basic anion exchange resins and weak basic anion exchange resins, depending on their basic strength. Either of them may be used in the present invention. The ion exchange resin has a classification such as a gel type, a porous type, and a high porous type depending on the difference in the polymer base structure such as the degree of cross-linking and porosity, and any of them may be used in the present invention. Examples of the polymer substrate include styrene-based, acrylic-based, and methacrylic-based materials, and styrene-based and acrylic-based materials are preferable. Examples of the functional group of the ion exchange resin include a quaternary ammonium group and a primary to tertiary amino group. These functional groups may be used alone or in combination of two or more. Also good. Specific examples of ion exchange resins suitable for the present invention include DIAION PA 312 (manufactured by Mitsubishi Chemical Corporation) as a strongly basic anion exchange resin, and DIAION WA21 (manufactured by Mitsubishi Chemical Corporation) as a weakly basic anion exchange resin. ) Can be illustrated respectively.

  In the present invention, the reason why the anion exchange resin effectively works to remove residual phosphoric acid in the organic layer is not necessarily clear, but is presumed as follows.

  In the organic layer in which the organic solvent, the phenolic resin and the residual phosphoric acid are present, the phenolic OH group of the phenolic resin and the OH group of the phosphoric acid form a chemical bond such as a hydrogen bond. It is presumed that a physical action such as water extraction forms a state in which it is difficult to remove residual phosphoric acid from the organic layer.

  On the other hand, chemical bonds are also formed between the ion exchange groups of the anion exchange resin and the residual phosphoric acid in the organic layer, but probably compared to the action of phenolic OH groups on phosphoric acid, Since the anion exchange resin has a stronger action on phosphoric acid, it is considered that phosphoric acid is captured by the anion exchange resin and removal of residual phosphoric acid proceeds efficiently.

  When the production method of the present invention is used, although it varies somewhat depending on the type of phenols, generally, depending on the range of the blending molar ratio (F / P) of aldehydes (F) and phenols (P), A novolac-type phenolic resin is obtained.

  When the blending molar ratio (F / P) is in the range of 0.80 mol or more, preferably 0.80 mol or more and 1.00 mol or less, the ratio between the phenolic monomer and the phenolic dimer is measured by the area method of gel filtration chromatography. The total content is 10% or less, preferably 5% or less, and the dispersion ratio (Mw / Mn) of the weight average molecular weight (Mw) and the number average molecular weight (Mn) by gel filtration chromatography is preferably 1.1 to A novolac-type phenol resin characterized by being 3.0, more preferably 1.2 to 2.0 can be produced in high yield.

  Further, when the blending molar ratio (F / P) is in the range of 0.33 or more and less than 0.80, the content of the phenolic monomer component is 3% or less, preferably 1%, as measured by the area method of gel filtration chromatography. In the following, the content of the phenolic dimer component is 5% to 95%, preferably 10% to 90%, and the dispersion ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) by gel filtration chromatography ( Mw / Mn) is 1.05 to 1.8, preferably 1.1 to 1.7, and a novolac type phenolic resin can be produced in a high yield.

  Examples The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. “%” Means “mass basis” unless otherwise specified. Moreover, the characteristic of the obtained novolak-type phenol resin was measured by the following test method.

(1) Phosphoric acid concentration Ion chromatograph IC-2001 manufactured by Tosoh Corporation (column: SuperIC-AP, solvent: 2.9 mM NaHCO ₃ +3.1 mM Na ₂ CO ₃ , flow rate: 0.8 ml / min, column temperature: 40 ° C).

(2) Number average molecular weight (Mn), weight average molecular weight (Mw), dispersion ratio (Mw / Mn)
Number average in terms of standard polystyrene as measured by Tosoh Corporation gel filtration chromatograph SC-8020 series build-up system (column: G2000H _XL + G4000H _XL , detector: UV254 nm, carrier: tetrahydrofuran 1 ml / min, column temperature 38 ° C.) The molecular weight (Mn) and the weight average molecular weight (Mw) were determined, and the dispersion ratio (Mw / Mn) was calculated.

(3) Content of phenolic monomers and phenolic dimers (%)
The area of the phenolic monomer and phenolic dimer with respect to the total area of the molecular weight distribution was measured by an area method that displays the percentage.

(4) Softening point Based on the ring-and-ball method described in JIS-K6910, it measured using the ring-and-ball type automatic softening point measuring apparatus ASP-MGK2 made by Meitec.

(5) Hue A 50% acetone solution of a novolak type phenolic resin was prepared as a sample, and ORBECO ANALYTIC SYSTEMS, INC. Using the Gardner-Heligue colorimeter “No. 600-DA (Color Disc: No. 620C-43)” manufactured by Gardner, the color tone of the sample and the color disc are compared, and the closest standard color number is selected. Judgment was made based on the following criteria.
○: 4 or less.
Δ: 5-7.
X: 8 or more.

<Example 1>
(First step)
In a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, 850 parts of phenol (P), 850 g of 89% by mass phosphoric acid (100% / P), and 127.5 parts of methanol as a reaction auxiliary solvent (15% / P), the contents were heated to about 60 ° C. with stirring and mixing. Next, 192.68 parts (F / P = 0.745) of 92% by mass paraform (F) was started to be added in portions, gradually using the heat of reaction under the cloudy state (two-phase mixture). The temperature was raised to the reflux temperature (98-110 ° C.). After dropwise addition over 2 hours, the reaction was further stopped after 4 hours of condensation reaction at reflux temperature.

(Second step)
After completion of the reaction, stirring and mixing were stopped and the mixture was allowed to stand and separated into an organic layer (upper layer) and an aqueous layer (lower layer), and 1050 parts of the aqueous layer was recovered.

  Next, 700 parts (82.4% / P) of a weakly basic anion exchange resin (“Diaion WA-21J” manufactured by Mitsubishi Chemical Corporation) was added to the organic layer, and the mixture was stirred at room temperature for 6 hours, followed by filtration. Separation was performed to remove the ion exchange resin. Table 1 shows the phosphoric acid concentration in the organic layer before and after the treatment with the ion exchange resin. Thereafter, residual moisture was completely removed by concentration under reduced pressure to obtain 900 parts of a novolak resin (yield 103% / P). The yield of novolak resin was expressed as a percentage with respect to the amount of phenol charged (mass basis).

  The evaluation results are shown in Table 1. In addition, “ND” in the table means that it was not detected.

<Example 2>
(First step)
Except for changing the formulation as shown in Table 1, the reaction was carried out in the same manner as in Example 1. After the reaction was stopped, 1540 parts of methyl isobutyl ketone, which is a water-insoluble organic solvent that works as a good solvent for the phenol resin, was added. The mixture was added with stirring and mixing to reduce the viscosity of the condensate and stirred for 30 minutes.

(Second step)
A novolak resin was obtained in the same manner as in Example 1 except that the ion-exchange resin treatment conditions were changed as shown in Table 1. The results are shown in Table 1.

<Example 3>
(First step)
Except for changing the formulation as shown in Table 1, the reaction was carried out in the same manner as in Example 1, and after stopping the reaction, 1700 parts of methyl isobutyl ketone, which is a water-insoluble organic solvent acting as a good solvent for the phenol resin, was added. The mixture was added with stirring to reduce the viscosity of the condensate, and further 1700 parts of pure water was added and stirred for 30 minutes.

(Second step)
A novolak resin was obtained in the same manner as in Example 1 except that the ion-exchange resin treatment conditions were changed as shown in Table 1. The results are shown in Table 1.

<Comparative Examples 1-3>
A novolak resin was obtained in the same manner as in Examples 1 to 3 except that the ion-exchange resin treatment was performed and the sample was washed with water under the conditions shown in Table 1. The results are shown in Table 1.

Claims (6)

  A first step of reacting phenols and aldehydes in a heterogeneous system in the presence of phosphoric acids; and after the first step, separating the aqueous layer by separating the aqueous layer and the organic layer; And a second step of contacting the ion exchange resin. A method for producing a novolac type phenol resin.   The method for producing a novolak type phenol resin according to claim 1, wherein, in the first step, a water-insoluble organic solvent that acts as a good solvent for the phenol resin is added after the reaction is stopped.   3. The method for producing a novolac type phenol resin according to claim 1, wherein in the first step, the phosphoric acid is 5 parts by mass or more with respect to 100 parts by mass of the phenols.   The said 1st process WHEREIN: The compounding quantity of aldehyde is 0.33 mol or more and 1.0 mol or less with respect to 1 mol of phenols, The novolak in any one of Claims 1-3 characterized by the above-mentioned. Type phenolic resin production method.   The method for producing a novolac type phenolic resin according to any one of claims 1 to 4, wherein in the first step, a non-reactive oxygen-containing organic solvent is present as a reaction auxiliary solvent.   6. The reaction cosolvent is at least one selected from the group consisting of alcohols, polyhydric alcohol ethers, cyclic ethers, polyhydric alcohol esters, ketones, and sulfoxides. Of producing a novolac-type phenolic resin.