JP4700306B2 - Method for producing novolac type phenolic resin - Google Patents

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, a so-called flammable hazardous material such as methyl ethyl ketone or methyl isobutyl ketone is used when the organic layer and the aqueous layer are separated after leaving the reaction.

  In general, flammable hazardous materials cannot be used in non-explosion-proof plants, and it has been difficult to apply these manufacturing methods to non-explosion-proof plants as they are.

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

  INDUSTRIAL APPLICABILITY The present invention can not only obtain a novolak type phenolic resin with controlled content and dispersion ratio of phenolic monomers and phenolic dimers in a high yield, but can also be applied to general non-explosion-proof plants. An object of the present invention is to provide a method for producing a novolak-type phenolic resin.

  That is, the method for producing a novolac type phenolic resin of the present invention comprises a first step in which a phenol and an aldehyde are reacted in a heterogeneous system in the presence of phosphoric acid, and a second step in which the phenol is added after the first step. And a process.

  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.

  Moreover, since it is not necessary to use a flammable dangerous material, it can be applied to a general non-explosion-proof plant.

  Furthermore, by using phenols after completion of the reaction, the organic layer and the aqueous layer can be sufficiently separated with a small addition amount, which is useful in terms of improving volumetric efficiency and reducing raw material costs.

  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 blending ratio (F / P) of the phenols (P) and the aldehydes (F) is not particularly limited, but is preferably 0.6 to 1.0, more preferably 0.65 to a molar basis. 0.97. If the blending ratio is less than 0.6, it may be difficult to reduce the content of components below the phenol dimer, whereas 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.

  This invention has the 2nd process which isolate | separates an organic layer and a water layer after adding phenols and leaving still after said 1st process.

  Specifically, after the first step, phenols are added and mixed while stirring and mixing to reduce the viscosity of the condensate (novolak type phenol resin) obtained in the first step, and then stirring and mixing are stopped. The mixture is allowed to stand and separated into an organic layer (including phenols and condensate) and an aqueous layer (including phosphoric acids and a reaction auxiliary solvent when added). Next, after removing the aqueous layer from the system, the phosphoric acid and the reaction auxiliary solvent are recovered, while the organic layer is washed with hot water and / or neutralized several times, and then the residual water and phenols are completely removed by concentration under reduced pressure. To remove.

  The phenols added in the second step include phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, 2,3-xylenol, 2,4 -Xylenol, 2,5-xylenol, 2,6-xylenol, 3,5-xylenol, 3,4-xylenol, etc. Among these, removal efficiency during vacuum concentration, handling properties, easy availability Phenol is preferable in terms of cost.

  Although the addition ratio of phenols is not specifically limited, Preferably it is 5-200 mass parts with respect to 100 mass parts of phenols used at the 1st process, More preferably, it is 10-50 mass parts. If the addition ratio is less than 5 parts by mass, the effect of reducing the viscosity due to the addition of phenols may not be obtained, and if it exceeds 200 parts by mass, it is not preferable from the viewpoint of volume efficiency and raw material cost. In addition, the addition ratio said here is a ratio except the unreacted phenols.

  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) 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.

(2) 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.

(3) Softening point Based on the ring and ball method described in JIS-K6910, the softening point was measured using a ring and ball automatic softening point measuring device ASP-MGK2 manufactured by Meitec Co., Ltd.

(4) Manufacturability at non-explosion-proof plant Evaluation was made according to the following criteria depending on the type of additive solvent added in the second step.
○: Risk of explosion and fire is low, and there is no problem when used in non-explosion-proof plants.
×: Explosion / fire hazard is high, and explosion-proof equipment is required for use.

(5) Separability The following criteria evaluated by visual judgment regarding the separability of the organic layer and the water layer in the second step.
○: Separation between the organic layer and the aqueous layer is good.
X: Separability between the organic layer and the aqueous layer is poor.

<Example 1>
(First step)
In a reaction kettle equipped with a thermometer, a stirrer, a superheater, and a condenser, 850 parts of phenol (P), 850 parts 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 of 92% by mass paraformaldehyde (F) (F / P = 0.745) was started to be divided and gradually added using heat of reaction under a cloudy state (two-phase mixture). The temperature was raised to the reflux temperature (98-110 ° C.). After 92 mass% paraformaldehyde was added in portions over 2 hours, a condensation reaction was further performed at reflux temperature for 4 hours, and then the reaction was stopped.

(Second step)
Next, 90 parts of phenol was added with stirring and mixing to lower the viscosity of the condensate, and stirring and mixing were stopped and allowed to stand, and an organic layer (phenol and reaction condensate layer: upper layer) and an aqueous layer (phosphorus). Acid aqueous solution and methanol layer: lower layer). Next, the aqueous layer was removed, and the organic layer was washed with water several times to remove phosphoric acid, and then the residual water and phenol were completely removed by concentration under reduced pressure to obtain 879 parts of novolak resin (yield 103% / P). It was. The yield of the 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.

<Examples 2 and 3, Comparative Examples 1 and 2>
A novolak resin was produced and evaluated in the same manner as in Example 1 except that the formulation in the first step and the additive solvent in the second step were changed as shown in Table 1. The results are shown in Table 1.

Claims (5)

  A novolak-type phenol resin comprising a first step in which a phenol and an aldehyde are reacted in a heterogeneous system in the presence of phosphoric acid, and a second step in which the phenol is added after the first step. Production method.   In the said 1st process, phosphoric acids are 5 mass parts or more with respect to 100 mass parts of phenols, The manufacturing method of the novolak-type phenol resin of Claim 1 characterized by the above-mentioned.   3. The novolac type phenol resin according to claim 1, wherein in the first step, the compounding amount of the aldehyde is 0.6 mol or more and 1.0 mol or less with respect to 1 mol of the phenol. Manufacturing method.   In the said 1st process, a non-reactive oxygen-containing organic solvent is made to exist as a reaction auxiliary | assistant solvent, The manufacturing method of the novolak-type phenol resin in any one of Claims 1-3 characterized by the above-mentioned.   The reaction auxiliary solvent 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.