JP2005200488A - Manufacturing method of aromatic hydrocarbon-modified novolak-type phenolic resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an aromatic hydrocarbon-modified novolak-type phenolic resin containing a small amount of an unreacted phenolic compound and having a narrow molecular weight distribution in a high yield. <P>SOLUTION: The manufacturing method of the aromatic hydrocarbon-modified novolak-type phenolic resin comprises reacting the phenolic compound with an aromatic hydrocarbon aldehyde resin and an aldehyde compound using a phosphoric acid compound as a catalyst. Preferably, at least 0.2 mole of the phosphoric acid compound is used for 1 mole of the phenolic compound and the phosphoric acid compound is phosphoric acid. Preferably, the thus-obtained aromatic hydrocarbon-modified phenolic resin contains at most 1 wt% of the unreacted phenolic compound and has a dispersion degree of the molecular weight distribution of 1.2-5.0. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for producing an aromatic hydrocarbon-modified novolac type phenol resin.

  The aromatic hydrocarbon-modified novolak type phenolic resin has a structure in which a monocyclic aromatic hydrocarbon compound or a polycyclic aromatic hydrocarbon compound is incorporated in the molecular structure of the novolak type phenolic resin. Compared to type phenolic resin, it has fewer phenolic hydroxyl groups and has excellent heat resistance, water resistance, dimensional stability and the like of the cured resin.

This aromatic hydrocarbon-modified novolak type phenol resin is obtained by mixing phenols, aromatic hydrocarbon aldehyde resins, and aldehydes with a small amount of inorganic acid or organic acid such as hydrochloric acid, sulfuric acid, oxalic acid, p-toluenesulfonic acid, xylenesulfonic acid. Is obtained as a catalyst.
Here, the molecular weight of the aromatic hydrocarbon-modified novolak-type phenol resin is generally adjusted by the reaction molar ratio of the aromatic hydrocarbon aldehyde resin to the aldehyde with respect to the phenols. In the case of obtaining a product, there is a problem that the molecular weight distribution tends to be widened.
Moreover, since the operation which remove | eliminates the remaining unreacted phenols is normally performed, there existed a problem that an actual modification | denaturation ratio differed with respect to the preparation component ratio.

As general means for narrowing the molecular weight distribution, there are a method of reacting in an organic solvent, a method of removing low molecular weight components by steam distillation or solvent washing, but in the case of the former, a low molecular weight aromatic hydrocarbon modified novolak type A phenol resin cannot be obtained, and in the latter case, there is a drawback that the yield is greatly reduced.
In addition, the aromatic hydrocarbon-modified novolak type phenolic resin produced is subjected to steam treatment at 120 to 195 ° C., thereby removing unreacted phenols and decomposing high molecular weight components. A method for obtaining an aromatic hydrocarbon-modified novolak type phenol resin is disclosed (for example, see Patent Document 1), but there is a problem that a reduction in yield accompanying removal of unreacted phenols and a complicated operation are required. there were.

  In order to solve such a problem, a method of reacting a phenol, an aromatic hydrocarbon aldehyde resin, and an aldehyde with an organic phosphonic acid as a catalyst is disclosed (for example, see Patent Document 2).

Japanese Patent Application Laid-Open No. 07-242719 JP 2002-167417 A

  The present invention provides a method for producing an aromatic hydrocarbon-modified novolak-type phenol resin having a low content of unreacted phenols and a narrow molecular weight distribution in a high yield.

Such an object is achieved by the following present inventions (1) to (5).
(1) A method for producing an aromatic hydrocarbon-modified novolac type phenol resin, which comprises reacting phenols, aromatic hydrocarbon aldehyde resins, and aldehydes with phosphoric acids as catalysts.
(2) The method for producing an aromatic hydrocarbon-modified novolak type phenol resin according to (1) above, wherein 0.2 mol or more of the phosphoric acid is used with respect to 1 mol of the phenol.
(3) The method for producing an aromatic hydrocarbon-modified novolak-type phenol resin according to (1) or (2), wherein the phosphoric acid is phosphoric acid.
(4) The aromatic hydrocarbon-modified novolak-type phenol resin has an unreacted phenol content of 1.0% by weight or less, and is modified with the aromatic hydrocarbon according to any one of the above (1) to (3) A method for producing a novolac type phenolic resin.
(5) The aromatic hydrocarbon-modified novolak type phenolic resin according to any one of (1) to (4), wherein the molecular weight distribution has a dispersity of 1.2 to 5.0. Type phenolic resin production method.

  The present invention reacts phenols, aromatic hydrocarbon aldehyde resins, and aldehydes with phosphoric acids as catalysts, and has a low content of unreacted phenols and an aromatic carbonization with a narrow molecular weight distribution. A hydrogen-modified novolac type phenolic resin can be produced in a high yield.

Below, the manufacturing method of the aromatic hydrocarbon modified | denatured novolak-type phenol resin of this invention is demonstrated.
The aromatic hydrocarbon-modified novolak-type phenol resin of the present invention is characterized by reacting phenols, aromatic hydrocarbon aldehyde resins, and aldehydes using phosphoric acids as catalysts.
Hereinafter, the aromatic hydrocarbon-modified novolak type phenol resin may be simply referred to as “modified phenol resin”, and the production method of the aromatic hydrocarbon-modified novolak type phenol resin may be simply referred to as “production method”.

  Although it does not specifically limit as phenols used in the manufacturing method of this invention, For example, cresol, such as phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2, 5-xylenol, 2,6-xylenol, 3,4-xylenol, xylenol such as 3,5-xylenol, ethylphenol such as o-ethylphenol, m-ethylphenol, p-ethylphenol, isopropylphenol, butylphenol, p -Butylphenol such as tert-butylphenol, p-tert-amylphenol, p-octylphenol, p-nonylphenol, alkylphenols such as p-cumylphenol, fluorophenol, chlorophenol, bromophenol, iodine Halogenated phenols such as phenol, monovalent phenol substitutes such as p-phenylphenol, aminophenol, nitrophenol, dinitrophenol and trinitrophenol, and monovalent phenols such as 1-naphthol and 2-naphthol, resorcin, Examples thereof include polyhydric phenols such as alkyl resorcin, pyrogallol, catechol, alkyl catechol, hydroquinone, alkyl hydroquinone, phloroglucin, bisphenol A, bisphenol F, bisphenol S, and dihydroxynaphthalene. These can be used alone or in combination of two or more.

Although it does not specifically limit as aldehydes used in the manufacturing method of this invention, For example, formaldehyde, paraformaldehyde, trioxane, acetaldehyde, propionaldehyde, polyoxymethylene, chloral, hexamethylenetetramine, furfural, glyoxal, n-butyraldehyde, Examples include caproaldehyde, allyl aldehyde, benzaldehyde, crotonaldehyde, acrolein, tetraoxymethylene, phenylacetaldehyde, o-tolualdehyde, and salicylaldehyde. These can be used alone or in combination of two or more.

In the aromatic hydrocarbon aldehyde resin used in the production method of the present invention, the aromatic hydrocarbon nucleus has a methylene bond [—CH ₂ —], an ether bond [—CH ₂ OCH ₂ —], an acetal bond [—CH ₂ (OCH ₂ ) A resin having a structure in which nCH ₂ −n = 1 to 3] is bonded and a methylol group [—CH ₂ OH] or the like is bonded to some terminal aromatic hydrocarbon nuclei.

  The aromatic hydrocarbon aldehyde resin used in the production method of the present invention is not particularly limited, and examples thereof include mesitylene formaldehyde resin, xylene formaldehyde resin, toluene formaldehyde resin, benzene formaldehyde resin, and naphthalene formaldehyde resin. These can be used alone or in combination of two or more.

Although it does not specifically limit as molecular weight of aromatic hydrocarbon aldehyde resin, What is number average molecular weight 300-1000 is preferable.
Those whose number average molecular weight is less than the above lower limit usually have a large content of unreacted aromatic hydrocarbons, and this is not substantially involved in the reaction even in the step of reacting with phenols. This also remains in the hydrocarbon phenol resin, which may affect the properties of the cured product. Moreover, when the thing exceeding the said upper limit is used, the modification | denaturation phenol resin obtained tends to be high molecular weight.

  Although it does not specifically limit as an oxygen content rate of aromatic hydrocarbon aldehyde resin, It is preferable that it is 5 to 20 weight%. Those having an oxygen content of less than the lower limit have low reactivity with phenols and may not be sufficiently incorporated into the modified phenolic resin in the production method of the present invention. On the other hand, if the above upper limit is exceeded, the reactivity may be too high, or the modified phenolic resin may be gelated during synthesis.

  Although it does not specifically limit as a softening point of aromatic hydrocarbon aldehyde resin, It is preferable to exist in the range of 40-140 degreeC. Those having a softening point less than the above lower limit usually have a large content of unreacted aromatic hydrocarbons, and this cannot substantially participate in the reaction even in the step of reacting with phenols. This may remain inside, and may affect the properties of the cured product. Moreover, when the thing exceeding the said upper limit is used, the modification | denaturation phenol resin obtained tends to be high molecular weight.

In the production method of the present invention, the reaction molar ratio of the phenols, aromatic hydrocarbon aldehyde resin, and aldehydes is not particularly limited, but the aromatic hydrocarbon aldehyde resin is regarded as the aldehyde source, and 1.0 equivalent of phenols. The equivalent sum of the reactive groups of the aromatic hydrocarbon aldehyde resin and the aldehyde is preferably 0.1 to 3.0 equivalents relative to (mol). More preferably, it is 0.5-1.0 equivalent.
When the said equivalent sum is less than the said lower limit, the amount of unreacted phenols contained in a modified phenol resin may increase. Moreover, since the modification | denaturation ratio by the aromatic hydrocarbon of the modified phenol resin obtained becomes low, the electrical insulation property and water resistance of resin cured | curing material may not fully be expressed.
On the other hand, when the equivalent sum exceeds the upper limit, the amount of unreacted aromatic hydrocarbon aldehyde resin contained in the modified phenol resin may increase. Moreover, molecular weight may become large, or it may gelatinize depending on reaction conditions. When the viscosity increases in this way, the moldability may be affected depending on the application.
Furthermore, since the ratio of modification by aromatic hydrocarbon of the resulting aromatic hydrocarbon phenol resin is increased, the electrical insulation and water resistance of the cured resin are improved, but the curability and adhesion to the substrate are reduced. There are things to do.

Here, as the reactive group when the aromatic hydrocarbon aldehyde resin reacts with phenols, [—CH ₂ OH], [—CH ₂ OCH ₂ —], [—CH ₂ O—], [—CH ₂ OCH ₂ OH] and the like. Therefore, the number of equivalents of reactive groups in the aromatic hydrocarbon aldehyde resin can be calculated from the oxygen content of the aromatic hydrocarbon aldehyde resin.

Although the ratio (equivalent ratio) of the reactive group of aromatic hydrocarbon aldehyde resin and aldehydes is not specifically limited, Aromatic hydrocarbon aldehyde resin: aldehydes = 0.5: 10-10: 0.5 Is more preferable, and 3:10 to 10: 3 is more preferable.
If the ratio of the aromatic hydrocarbon aldehyde resin is higher than the above upper limit value, the modification rate of the resulting modified phenol resin by the aromatic hydrocarbon increases, and the electrical insulation and water resistance are improved, but the curability, base material Adhesiveness may decrease. Moreover, when the ratio of aldehydes is higher than the said upper limit, sclerosis | hardenability and adhesiveness with a base material will become favorable, but the tendency for the electrical insulating property or the improvement effect of water resistance to become small is seen.

In the production method of the present invention, phosphoric acids are used as a catalyst.
Here, as the phosphoric acid, a phosphoric acid compound that can be dissolved in water to form a phosphoric acid aqueous solution can be used, and is not particularly limited. For example, phosphoric acid (orthophosphoric acid), diphosphoric acid, triphosphoric acid, etc. In addition to linear polyphosphoric acid, cyclic polyphosphoric acid, diphosphorus pentoxide, phosphorous acid, hypophosphorous acid and the like, various phosphoric acid ester compounds can be mentioned. These can be used alone or in combination of two or more.

  Of these phosphoric acids, phosphoric acid is preferred. Phosphoric acid can be easily adjusted in concentration and can be obtained at low cost.

  Although it does not specifically limit as a density | concentration of phosphoric acid at the time of using phosphoric acid in the form of aqueous solution, It is preferable that it is 20 to 99 weight%, More preferably, it is 40 to 99 weight%. By setting the concentration of phosphoric acid in the phosphoric acid aqueous solution to be equal to or higher than the above lower limit, the reaction between the phenol, the aromatic hydrocarbon aldehyde resin, and the aldehyde can be efficiently advanced.

Here, the amount of phosphoric acid is not particularly limited, but is preferably 0.2 mol or more with respect to 1 mol of phenols. Thus, in a system in which phenols are reacted with an aromatic hydrocarbon aldehyde resin and aldehydes using an aqueous solution of phosphoric acid, an organic phase mainly composed of phenols or aromatic hydrocarbon aldehyde resin, and phosphoric acids The distribution with the aqueous phase containing can be stabilized.
The amount of the phosphoric acid is more preferably 0.3 to 1.0 mol, and particularly preferably 0.4 to 0.9 mol, with respect to 1 mol of phenols. Thereby, the modified phenol resin with little content of unreacted phenols can be obtained efficiently.

  Increasing the amount of phosphoric acid tends to increase the effect of obtaining a modified phenolic resin with a low content of unreacted phenols in a high yield, but 1.0 mol per mol of phenols. Even if the amount is exceeded, this effect may not be substantially changed, so that it may not be economical. On the other hand, if the amount is less than 0.2 mol, the phosphoric acid concentration in the aqueous phase is too low to stably distribute the organic phase and the aqueous phase, so that the reaction rate decreases.

In the production method of the present invention, together with the above phosphoric acids, other catalysts are usually used for producing novolak-type phenol resins such as hydrochloric acid, sulfuric acid, oxalic acid, p-toluenesulfonic acid, and xylenesulfonic acid. Acid catalysts, or polycarboxylic acids such as oxypolycarboxylic acids and aminopolycarboxylic acids that are effective in obtaining novolak-type phenolic resins with little unreacted phenols and a narrow molecular weight distribution.

  In the production method of the present invention, the water content in the reaction system when the phenols, aromatic hydrocarbon aldehyde resin and aldehydes are reacted using phosphoric acids is not particularly limited, but is 1 to 40 weights. % Is preferable. More preferably, it is 1 to 30% by weight.

  Here, the water content in the reaction system is present in the reaction system with respect to the total amount of phenols, aromatic hydrocarbon aldehyde resins, aldehydes, phosphoric acid aqueous solutions, modified phenol resins, etc. existing in the reaction system. It refers to the weight ratio of the total amount of water to be used. The water present in the reaction system in the production method of the present invention includes condensed water generated by the reaction in addition to the water contained in the phosphoric acid aqueous solution and aldehydes.

  The water content in the reaction system can be calculated by dividing the amount of water present in the reaction system by the total amount charged. Moreover, when making it react, distilling and removing water, it can calculate similarly by reducing the water content which distilled off and making it the water content in a reaction system.

By carrying out the reaction preferably within the above range for this water content, a modified phenolic resin with a low content of unreacted phenols can be obtained in high yield.
By setting the water content in the reaction system to the above lower limit value or more, it is possible to prevent the phosphoric acids from becoming highly viscous or solidified. Moreover, since the fall of reaction rate can be suppressed by setting it as the said upper limit or less, reaction with phenols, aromatic hydrocarbon aldehyde resin, and aldehydes can be advanced efficiently.

Although it does not specifically limit as reaction temperature at the time of making phenols react with aromatic hydrocarbon aldehyde resin and aldehydes using phosphoric acids, It is preferable that it is 60 to 240 degreeC. More preferably, it is 80-150 degreeC.
By making reaction temperature more than the said lower limit, reaction with phenols, aromatic hydrocarbon aldehyde resin, and aldehydes can be accelerated | stimulated, and content of unreacted phenols can be reduced. Moreover, it can make phosphoric acid aqueous solution into a preferable viscosity, and can avoid that a catalytic action falls. On the other hand, the decomposition of the modified phenolic resin can be suppressed by setting it to the upper limit value or less.

  Although it does not specifically limit as a reaction form in the manufacturing method of this invention, For example, there exists the method of making phenols, aromatic hydrocarbon aldehyde resin, and aldehydes react under atmospheric distillation reaction, According to this method, This is a preferable condition because the temperature and moisture can be easily controlled and the condensation component produced during the reaction can be distilled off.

As a reaction solvent, water is common and preferable, but an organic solvent can also be used. Moreover, you may carry out by non-aqueous system using a nonpolar solvent. Alternatively, paraform or the like may be used without a reaction solvent.
Here, alcohols, ketones, aromatics and the like can be used as the organic solvent. Examples of alcohols include butanol, propyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, and glycerin. Examples of ketones include methyl ethyl ketone, and examples of aromatics include toluene and xylene.

In the reaction, an antifoaming agent, a surfactant or the like can be used for stabilizing the reaction, if necessary.
The stirring conditions during the reaction are not particularly limited, but it is preferable to stir at a high speed. As a result, the surface area of the contact interface between the water phase and the organic phase increases during the reaction, so that a modified phenol resin with a small content of unreacted phenols and a narrow molecular weight distribution can be efficiently produced.
After completion of the synthesis of the modified phenolic resin, it is possible to carry out atmospheric distillation, vacuum distillation, steam distillation or the like to remove water, organic solvent, and unreacted phenols as necessary.

In the production method of the present invention, the reaction method of the phenols with the aromatic hydrocarbon aldehyde resin and aldehydes is not particularly limited.
(1) A method in which phenols, aldehydes and a catalyst are charged and reacted, and then an aromatic hydrocarbon aldehyde resin is further added and reacted.
(2) A method in which phenols, an aromatic hydrocarbon aldehyde resin and a catalyst are charged and reacted, and then aldehydes are added and reacted.
(3) A method in which a phenol and a catalyst are charged, and an aromatic hydrocarbon aldehyde resin and an aldehyde are added and reacted therewith,
Etc. In any of the above reaction methods, in order to suppress heat generation during the reaction, when the phenols are reacted with the aromatic hydrocarbon aldehyde resin and / or aldehydes, the aromatic hydrocarbon aldehyde resin and / or Aldehydes can be added sequentially to react.

Conventionally, as a method for synthesizing an aromatic hydrocarbon-modified phenol resin, the method (2) has been generally used. This is because, when the method (1) or (3) is performed, the polymer is easily polymerized or gelated even when the amount of modification with the aromatic hydrocarbon aldehyde resin is small.
On the other hand, in the production method of the present invention, in the reaction between phenols and aromatic hydrocarbon aldehyde resin, or in the reaction between phenols and aldehydes, both are more than the further reactivity of the reaction product. The phenol monomers have the highest reactivity and are difficult to increase in molecular weight.
For this reason, for example, as in the method (1) above, even if the reaction between phenols and aldehydes is performed first, the reaction product contains dinuclear components as long as the reaction molar ratio is within a predetermined range. The composition is mainly composed. And even if this is reacted with an aromatic hydrocarbon aldehyde resin, there is an advantage that the reaction can proceed without any problem and the reaction product is less likely to have a high molecular weight.

Although it does not specifically limit in the manufacturing method of this invention, After synthesize | combining a modified phenol resin by the method demonstrated above, the reaction system is washed with water, The density | concentration of phosphoric acid contained in a modified phenol resin is 3.0 weight. % Or less is preferable. More preferably, it is 0.1 weight% or less.
Thereby, when performing atmospheric distillation or vacuum distillation after washing with water, decomposition of the modified phenolic resin can be suppressed.

  Although it does not specifically limit as a method to wash with water here, For example, the organic phase containing modified phenol resin and the aqueous phase containing phosphoric acid aqueous solution are isolate | separated by centrifugation. Next, by washing the obtained organic phase with pure water or ion exchange water, the concentration of phosphoric acids contained in the modified phenolic resin can be reduced to 3.0% by weight or less. Moreover, the concentration of phosphoric acids can be reduced to 0.1% by weight or less by performing this water washing a plurality of times.

Further, after washing with water until the concentration of phosphoric acid is equal to or lower than the above upper limit, 0.8 to 1.5 equivalents of alkaline substance is used with respect to 1 equivalent of phosphoric acid remaining in the reaction system. Neutralization is preferred. Thereby, since the catalytic activity which phosphoric acid has can be deactivated, even when performing a distillation reaction at a high temperature in the subsequent steps, decomposition of the modified phenolic resin can be suppressed.

  Although it does not specifically limit as an alkaline substance used here, For example, calcium hydroxide, sodium hydroxide, a triethanolamine etc. can be used. Although it does not specifically limit as a form of an alkaline substance, It is preferable to use with the form of aqueous solution.

The content of unreacted phenols in the modified phenolic resin obtained by the production method of the present invention is not particularly limited, but is preferably 1.0% by weight or less, more preferably 0.5% by weight or less. .
In the production method of the present invention, phenols, aromatic hydrocarbon aldehyde resins and aldehydes, phosphoric acids, an organic phase containing phenols, aromatic hydrocarbon aldehyde resins, etc., and phosphoric acids are contained. By performing a liquid-liquid heterogeneous reaction with the aqueous phase to be carried out, the content of unreacted phenols can be reduced to the above upper limit value or less. Moreover, in order to remove unreacted phenols, atmospheric distillation, vacuum distillation, steam distillation, etc. can also be performed as needed.

The degree of dispersion of the molecular weight distribution of the modified phenolic resin obtained by the production method of the present invention (dispersion degree = weight average molecular weight / number average molecular weight) is not particularly limited, but is preferably 1.2 to 5.0. . More preferably, it is 1.2-4.0.
In the production method of the present invention, by performing the liquid-liquid heterogeneous reaction, the content of unreacted phenols can be reduced and an increase in the high molecular weight component can be suppressed. Thereby, the dispersion degree of molecular weight distribution can be made into the said range.

In the production method of the present invention, the content of unreacted phenols is a value measured by an internal standard method using 2,5-xylenol as an internal standard substance using a gas chromatography method in accordance with JIS K 0114. is there.
Further, the weight average molecular weight and the number average molecular weight are measured using a liquid chromatography method. Here, the liquid chromatography method uses GPC (gel permeation chromatography) and uses a differential refractometer using tetrahydrofuran as an elution solvent at a flow rate of 1.0 ml / min and a column temperature of 40 ° C. Measured as a detector, the molecular weight was converted with standard polystyrene.
The device
1) Body: "HLC-8120" manufactured by TOSOH
2) Analysis column: manufactured by TOSOH, “G1000HXL”, “G2000HXL”, “G3000HXL”,
It was used.

  In the production method of the present invention, by reacting phenols, aromatic hydrocarbon aldehyde resins and aldehydes with phosphoric acids, a modified phenol resin having a small content of unreacted phenols and a narrow molecular weight distribution. The reason why can be obtained in a high yield is considered as follows.

Phosphoric acids used in the production method of the present invention are very water-soluble and easily hydrated, and are poorly soluble in phenols and aromatic hydrocarbon aldehyde resins. On the other hand, the solubility is further lowered with the increase in the molecular weight.
For this reason, at the time of reaction, it is in a state of being phase-separated into an aqueous phase containing a large amount of catalyst phosphoric acid and an organic phase in which almost no catalyst having phenols, aromatic hydrocarbon aldehyde resin, modified phenol resin, etc. exists. . Here, low molecular weight components such as phenols, aromatic hydrocarbon aldehyde resins, and initial reaction products are relatively easily eluted in the aqueous phase, but the reaction proceeds relatively easily, but high molecular weight components are hardly eluted and substantially Since the reaction does not proceed, the modified phenol resin produced by reacting in the aqueous phase is quickly extracted into the organic phase, and the reaction rate for increasing the molecular weight becomes relatively small.
Thus, in the reaction system according to the production method of the present invention, the low molecular weight component and the high molecular weight component cause a difference in reaction rate due to the difference in solubility in the aqueous phase, and low molecular weight components such as phenolic monomers are present. While reacting selectively, it can suppress that produced | generated modified phenol resin becomes high molecular weight too much. As a result, a modified phenol resin having a small content of unreacted phenols and a narrow molecular weight distribution can be produced in a high yield.

  Hereinafter, the present invention will be described in detail with reference to examples. Here, “parts” indicates “parts by weight” and “%” indicates “% by weight”.

<Example 1>
In a 3 L three-necked flask equipped with a stirrer and a thermometer, 1500 parts of phenol, 1000 parts of aromatic hydrocarbon aldehyde resin A, 1500 parts of 85% phosphoric acid aqueous solution (corresponding to 0.82 moles per mole of phenols) Was charged. This was heated to 140 ° C. and refluxed for 4 hours.
Next, 141 parts of 92% paraformaldehyde was added every time and reacted at 110 ° C. for 1 hour while refluxing.
Thereafter, 2000 parts of methyl ethyl ketone was added, the temperature was lowered to 60 ° C., 2000 parts of pure water was added, and the aqueous phase separated from the resin phase was removed. Further, 1000 parts of pure water was added, and a water washing step for removing the aqueous phase separated from the resin phase was performed three times. The amount of phosphoric acid remaining in the resin after washing with water was measured and found to be 0.07 parts.
Thereafter, 0.06 part of a 50% aqueous sodium hydroxide solution (1.2 equivalents relative to 1 equivalent of the remaining phosphoric acid) was added, and atmospheric distillation was performed, the temperature was raised to 130 ° C., and the pressure was reduced at a reduced pressure of 5000 Pa. Distillation was performed and the temperature was raised to 180 ° C. to obtain 2493 parts of a modified phenolic resin.

<Example 2>
In a 3 L three-necked flask equipped with a stirrer and a thermometer, 1500 parts of phenol, 500 parts of aromatic hydrocarbon aldehyde resin A, 1500 parts of 85% aqueous phosphoric acid solution (corresponding to 0.82 moles per mole of phenols) Was charged. This was heated to 140 ° C. and refluxed for 4 hours.
Next, 242 parts of 92% paraformaldehyde was added every time and reacted at 110 ° C. with refluxing for 1 hour.
Thereafter, 2000 parts of methyl ethyl ketone was added, the temperature was lowered to 60 ° C., 2000 parts of pure water was added, and the aqueous phase separated from the resin phase was removed. Further, 1000 parts of pure water was added, and a water washing step for removing the aqueous phase separated from the resin phase was performed three times. The amount of phosphoric acid remaining in the resin after washing with water was measured and found to be 0.07 parts.
Thereafter, 0.06 part of a 50% aqueous sodium hydroxide solution (1.2 equivalents relative to 1 equivalent of the remaining phosphoric acid) was added, and atmospheric distillation was performed, the temperature was raised to 130 ° C., and the pressure was reduced at a reduced pressure of 5000 Pa. Distillation was performed and the temperature was raised to 180 ° C. to obtain 1998 parts of a modified phenolic resin.

<Example 3>
In a 3 L three-necked flask equipped with a stirrer and a thermometer, 1500 parts of phenol, 1000 parts of aromatic hydrocarbon aldehyde resin A, 644 parts of 85% aqueous phosphoric acid solution (corresponding to 0.35 moles per mole of phenols) Was charged. This was heated to 130 ° C. and refluxed for 4 hours.
Next, 211 parts of 92% paraformaldehyde was added every time, and the reaction was carried out while refluxing at 110 ° C. for 1 hour.
Thereafter, 2000 parts of methyl ethyl ketone was added, the temperature was lowered to 60 ° C., 2000 parts of pure water was added, and the aqueous phase separated from the resin phase was removed. Furthermore, 2000 parts of pure water was added, and the water washing process which removes the water phase isolate | separated from the resin phase was performed 3 times. When the amount of phosphoric acid remaining in the resin after washing with water was measured, it was below the detection limit.
Thereafter, atmospheric distillation was performed, the temperature was raised to 130 ° C., vacuum distillation was performed at a reduced pressure of 5000 Pa, and the temperature was raised to 180 ° C. to obtain 2501 parts of a modified phenolic resin.

<Example 4>
In a 3 L three-necked flask equipped with a stirrer and a thermometer, 1200 parts of phenol, 1000 parts of aromatic hydrocarbon aldehyde resin B, 1200 parts of 85% phosphoric acid aqueous solution (corresponding to 0.82 moles per mole of phenols) Was charged. This was heated to 120 ° C. and refluxed for 4 hours.
Next, 141 parts of 92% paraformaldehyde was added every time and reacted at 100 ° C. with refluxing for 1 hour.
Thereafter, 2000 parts of methyl ethyl ketone was added, the temperature was lowered to 60 ° C., 2000 parts of pure water was added, and the aqueous phase separated from the resin phase was removed. Further, 1000 parts of pure water was added, and a water washing step for removing the aqueous phase separated from the resin phase was performed three times. The amount of phosphoric acid remaining in the resin after washing with water was measured and found to be 0.07 parts.
Thereafter, 0.06 part of a 50% aqueous sodium hydroxide solution (1.2 equivalents relative to 1 equivalent of the remaining phosphoric acid) was added, and atmospheric distillation was performed, the temperature was raised to 130 ° C., and the pressure was reduced to 5000 Pa. Distillation was performed and the temperature was raised to 180 ° C. to obtain 2195 parts of a modified phenolic resin.

<Example 5>
In a 3 L three-necked flask equipped with a stirrer and a thermometer, 1500 parts of phenol, 141 parts of 92% paraformaldehyde, and 1500 parts of 85% phosphoric acid aqueous solution (corresponding to 0.82 moles per mole of phenols) are charged. It is. This was heated to 130 ° C. and reacted for reflux for 1 hour.
Next, 1000 parts of aromatic hydrocarbon aldehyde resin A was added, the temperature was raised to 140 ° C. while performing atmospheric distillation, and a reflux reaction was performed for 4 hours.
Thereafter, 2000 parts of methyl ethyl ketone was added, the temperature was lowered to 60 ° C., 2000 parts of pure water was added, and the aqueous phase separated from the resin phase was removed. Further, 1000 parts of pure water was added, and a water washing step for removing the aqueous phase separated from the resin phase was performed three times. The amount of phosphoric acid remaining in the resin after washing with water was measured and found to be 0.07 parts.
Thereafter, 0.06 part of a 50% aqueous sodium hydroxide solution (1.2 equivalents relative to 1 equivalent of the remaining phosphoric acid) was added, and atmospheric distillation was performed, the temperature was raised to 130 ° C., and the pressure was reduced at a reduced pressure of 5000 Pa. Distillation was performed and the temperature was raised to 180 ° C. to obtain 2489 parts of a modified phenolic resin.

<Example 6>
In a 3 L three-necked flask equipped with a stirrer and a thermometer, 1500 parts of phenol, 242 parts of 92% paraformaldehyde, 1500 parts of 85% phosphoric acid aqueous solution (corresponding to 0.82 moles per mole of phenols) are charged. It is. This was heated to 130 ° C. and reacted for reflux for 1 hour.
Next, 500 parts of aromatic hydrocarbon aldehyde resin B was added, the temperature was raised to 140 ° C. while performing atmospheric distillation, and a reflux reaction was performed for 4 hours.
Thereafter, 2000 parts of methyl ethyl ketone was added, the temperature was lowered to 60 ° C., 2000 parts of pure water was added, and the aqueous phase separated from the resin phase was removed. Further, 1000 parts of pure water was added, and a water washing step for removing the aqueous phase separated from the resin phase was performed three times. The amount of phosphoric acid remaining in the resin after washing with water was measured and found to be 0.07 parts.
Thereafter, 0.06 part of a 50% aqueous sodium hydroxide solution (1.2 equivalents relative to 1 equivalent of the remaining phosphoric acid) was added, and atmospheric distillation was performed, the temperature was raised to 130 ° C., and the pressure was reduced to 5000 Pa. Distillation was performed and the temperature was raised to 180 ° C. to obtain 1998 parts of a modified phenolic resin.

<Comparative Example 1>
In a 3 L three-necked flask equipped with a stirrer and a thermometer, 1500 parts of phenol, 1000 parts of xylene formaldehyde resin A, and 1 part of paratoluenesulfonic acid were charged and heated to 110 ° C. and reacted for 2 hours. 15 parts of oxalic acid and 141 parts of 92% paraformaldehyde were sequentially added and refluxed at 100 ° C. for 1 hour.
Thereafter, 15 parts of slaked lime was added, atmospheric distillation was performed, the temperature was increased to 150 ° C., vacuum distillation was performed at a reduced pressure of 5000 Pa, and the temperature was increased to 190 ° C. to obtain 2310 parts of a phenol resin.

<Comparative Example 2>
In a 3 L three-necked flask equipped with a stirrer and a thermometer, 1200 parts of phenol, 1000 parts of xylene formaldehyde resin B, and 10 parts of paratoluenesulfonic acid were charged, heated to 110 ° C., and reacted for 2 hours. Thereafter, 141 parts of 92% paraformaldehyde and 35 parts of zinc oxide were added and reacted at 100 ° C. for 3 hours.
Thereafter, atmospheric distillation was performed, the temperature was raised to 130 ° C., vacuum distillation was performed at a reduced pressure of 5000 Pa, and the temperature was raised to 160 ° C. to obtain 2098 parts of a phenol resin.

The raw materials used in Examples 1 to 6 and Comparative Examples 1 and 2 are as follows.
(1) Aromatic hydrocarbon aldehyde resin A
・ Mitsubishi Gas Chemical Co., Ltd. ・ Xylene formaldehyde resin “Nikanol G”
Number average molecular weight 570
・ Oxygen content 15%
(2) Aromatic hydrocarbon aldehyde resin B
・ Mitsubishi Gas Chemical Co., Ltd. ・ Xylene formaldehyde resin “Nikanol H”
Number average molecular weight 480
・ Oxygen content 10%
(3) 92% paraformaldehyde Made by Mitsubishi Chemical

  Table 1 shows the modified phenolic resins obtained in Examples 1 to 6 and the phenolic resins obtained in Comparative Examples 1 and 2.

<Notes on the table>
The evaluation method is as follows.
(1) Amount of unreacted phenol: measured by gas chromatography.
Gas chromatography: In accordance with JIS K 0114, 2,5-xylenol was used as an internal standard and measured by an internal standard method.
(2) Number average molecular weight, weight average molecular weight: Measured using a liquid chromatography method.
The liquid chromatography method uses GPC (gel permeation chromatography), uses tetrahydrofuran as an elution solvent, detects a differential refractometer at a flow rate of 1.0 ml / min, and a column temperature of 40 ° C. The molecular weight was converted by standard polystyrene.
The device
1) Body: "HLC-8120" manufactured by TOSOH
2) Analysis column: manufactured by TOSOH, “G1000HXL”, “G2000HXL”, “G3000HXL”,
It was used.
(3) Softening point: Measured according to JIS K2531.
(4) Kinematic viscosity of 50% ethanol solution: A 50% ethanol solution was prepared and measured at 25 ° C. using a Canon Fenceke.
(5) Yield: The amount (parts) relative to 1000 parts of the sum of the charged phenol and the aromatic hydrocarbon aldehyde resin.

  Examples 1 to 6 are modified phenolic resins obtained by the production method of the present invention in which phenols, aromatic hydrocarbon aldehyde resins, and aldehydes are reacted using phosphoric acids as catalysts. Compared with the obtained Comparative Examples 1 and 2, the content of unreacted phenols was small, and those having a narrow molecular weight could be produced with a high yield.

The present invention is a production method capable of obtaining an aromatic hydrocarbon-modified phenol resin with a small amount of unreacted phenols and a narrow molecular weight distribution in a high yield.
The aromatic hydrocarbon-modified phenolic resin obtained by the production method of the present invention can be used, for example, as a friction material, a grindstone, a laminate, a molding material, a binder for an adhesive, a curing agent for an epoxy resin, a raw material for an epoxy resin, etc. It is preferably used.

Claims (5)

A process for producing an aromatic hydrocarbon-modified novolak-type phenol resin, comprising reacting phenols, aromatic hydrocarbon aldehyde resins, and aldehydes with phosphoric acids as catalysts. The method for producing an aromatic hydrocarbon-modified novolak type phenol resin according to claim 1, wherein 0.2 mol or more of the phosphoric acid is used with respect to 1 mol of the phenol. The method for producing an aromatic hydrocarbon-modified novolac type phenol resin according to claim 1 or 2, wherein the phosphoric acid is phosphoric acid. 4. The production of an aromatic hydrocarbon-modified novolak-type phenol resin according to claim 1, wherein the aromatic hydrocarbon-modified novolak-type phenol resin has an unreacted phenol content of 1.0% by weight or less. 5. Method. The method for producing an aromatic hydrocarbon-modified novolak type phenol resin according to any one of claims 1 to 4, wherein the aromatic hydrocarbon-modified novolak type phenol resin has a molecular weight distribution of 1.2 to 5.0. .