JPH1087538A - Polyhydroxy compound, its production, and epoxy resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyhydroxy compound which shows a narrow range of molecular weight distribution, can impart excellent resistance to heat and chemicals to cured epoxy resin and is useful as a curing agent by allowing a phenol to react with a specific bis-phenol dimethylol derivative. SOLUTION: The polyhydroxy compound is represented by formula I (R<1> and R<2> are each a 1-9C hydrocarbon group; R<3> and R<4> are each H, a 1-6C hydrocarbon group; R5 and R6 are each a 1-4C hydrocarbon group, a halogen) and is prepared, for example, by allowing 2-20 pts.wt. of a compound of formula III to condense with 1 mole of formula II under acidic conditions using oxalic acid or the like followed by removal of monomers through distillation under reduced pressure, thin-layer distillation, (reduced pressure) steam distillation or the like. The condensation reaction is carried out with heat usually at 50-100 deg.C, preferably at 80-100 deg.C for 1-6 hours.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polyhydroxy compound, a production method and an epoxy resin composition. More specifically, the polyhydroxy compound of the present invention is a novel polyhydroxy compound having a low molecular weight distribution with a low content of trinuclear or less components and a tetranuclear component as a main component. Available as

[0002]

2. Description of the Related Art Conventionally, epoxy resins have been used for various purposes such as paints, laminates, and electric and electronic materials. The epoxy resin is generally used in combination with a curing agent. In particular, in the field of electric and electronic materials, a phenol novolak resin is suitably used as the curing agent.

A phenol novolak resin is generally obtained by a condensation reaction of phenols and formaldehyde in the presence of an acid catalyst, and is a linear molecule mainly composed of 2 to 20 phenol nuclei linked by a methylene bond. It is believed that there is. However, the phenol novolak resin thus obtained contains unreacted phenol monomers and low molecular weight components consisting of binucles,
When this is used as a curing agent, it is difficult to provide a cured product having a high crosslinking density, and the resulting cured product has a disadvantage that heat resistance, chemical resistance, mechanical properties and the like cannot be satisfied. On the other hand, the phenol novolak resin has a drawback that, since it contains a large amount of a relatively high molecular weight component of 5 or more nuclei, the flowability at the time of molding in the above application is not sufficient, and as a result, the workability is poor. .

A co-condensed novolak resin obtained by simultaneously charging two or more kinds of phenols and formaldehyde and subjecting them to a condensation reaction is also known. However, this is also the same as the general phenol novolak resin described above. Is wide and the content of monomer is 1% by weight
Even in the case of adjusting below, it contains a large amount of low molecular weight components such as binuclear and high molecular weight components such as pentanuclear or more. That is, the phenol novolak resin generally has a polydispersity (M
w / Mn and Mw are weight-average molecular weight values, and Mn is a number-average molecular weight value). Therefore, when this is used as a curing agent for an epoxy resin, the heat resistance of the cured product,
The chemical resistance, mechanical properties, etc. could not be satisfied, and the workability was poor.

[0005]

SUMMARY OF THE INVENTION The present invention provides a phenolic resin-based polyhydroxy compound having a tetranuclear component as a main component and a narrow molecular weight distribution having excellent properties as a curing agent for an epoxy resin. With the goal.

[0006]

Means for Solving the Problems In order to solve the above-mentioned problems of the prior art, the present inventors have conducted intensive studies and found that an excess amount of phenols was added to the dimethylol compound of a specific bisphenol compound in the presence of an acid catalyst. The present inventors have found that a polyhydroxy compound obtained by the following reaction meets the above object, and have completed the present invention.

That is, the present invention provides a compound represented by the general formula (1):

[0008]

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Wherein R ¹ and R ² each represent a hydrocarbon group having 1 to 9 carbon atoms, and R ³ and R ⁴ represent a hydrogen atom or a carbon atom having 1 to 9 carbon atoms.
And R ⁵ and R ⁶ each independently represent a hydrogen atom, a hydrocarbon group having 1 to 4 carbon atoms or a halogen atom. A) a polyhydroxy compound represented by the general formula (2):

[0010]

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Wherein R ¹ and R ² each represent a hydrocarbon group having 1 to 9 carbon atoms, and R ³ and R ⁴ represent a hydrogen atom or a carbon atom having 1 to 9 carbon atoms.
6 represents a hydrocarbon group. ) With respect to 1 mol part of the dimethylol compound of the bisphenol compound represented by the general formula (3):

[0012]

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(Wherein R ⁵ and R ⁶ each independently represent a hydrogen atom, a hydrocarbon group having 1 to 4 carbon atoms or a halogen atom). The present invention relates to a method for producing a polyhydroxy compound, which comprises condensing under conditions and further demonomerizing, and an epoxy resin composition containing the polyhydroxy compound, a polyfunctional epoxy resin and a curing accelerator.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION The general formula (2):

[0015]

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(Wherein R ¹ and R ² represent a hydrocarbon group having 1 to 9 carbon atoms, and R ³ and R ⁴ represent a hydrogen atom or a carbon atom having 1 to 9 carbon atoms)
6 represents a hydrocarbon group. The dimethylol derivative of the bisphenol compound represented by the formula (1) is a starting material for producing the polyhydroxy compound represented by the formula (1). Examples of the hydrocarbon group having 1 to 9 carbon atoms representing R ¹ and R ² include a linear or branched alkyl group, an aryl group such as a phenyl group, a cyclohexyl group, and an allyl group. Further, the above-mentioned R ³ and R ^{4 each} have 1 carbon atom.
Examples of the hydrocarbon groups 6 to 6 include a straight-chain or branched-chain alkyl group, an aryl group such as a phenyl group, and the like, and R ³ and R ⁴ bond to form a cyclolohexylene group. And the like. R ¹ and R ² are preferably an alkyl group, and R ³ and R ⁴ are preferably a hydrogen atom or an alkyl group. These may be used alone or in combination of two or more.

The dimethylol derivative of the bisphenol compound represented by the general formula (2) is represented by the general formula (4):

[0018]

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(Wherein R ^{1 to} R ⁴ are the same as described above), 1 mol part of a bisphenol compound and about 2 to 3 mol parts of formaldehyde or a formaldehyde generating substance are mixed with water and a basic catalyst. Below 30 ~ 80 ℃
After a methylolation reaction for about 1 hour to several hours, a high-purity solid can be obtained by acid precipitation. The dimethylol form of the bisphenol compound represented by the general formula (2) is obtained by reacting a bisphenol compound with formaldehyde or a formaldehyde-generating substance in the presence of water and a basic catalyst in the same manner as described above. Then, the resole type oily substance obtained by neutralizing with an acid can be used as it is without any purification.

The bisphenol compounds represented by the general formula (4) include 4,4 '-(1-methylethylidene) bis [2-methylphenol] and 5,5'-(1-
Methylethylidene) bis [1,1′-biphenyl] -2
-Ol, 4,4 '-(1-methylethylidene) bis [2- (2-propenyl) phenol], 4,4'-
(1-methylethylidene) bis [2- (1,1-dimethylethyl) phenol], 4,4 ′-(1-methylethylidene) bis [2- (1,1-methylpropyl) phenol], 4,4 '-Methylenebis [2-methylphenol], 4,4'-(1-methylethylidene) bis [2-
(1-methylethyl) phenol], 4,4 '-(1-
Phenylethylidene) bis [2-methylphenol],
4,4'-methylenebis [2- (2-propenyl) phenol], 4,4 '-(1-methylethylidene) bis [2-cyclohexylphenol], 2,2'-methylenebis [4-nonylphenol], 4, 4'-cyclohexylidenebis [3-methylphenol], 4,4'-
Cyclohexylidenebis [2- (1,1-dimethylethyl) phenol], 5,5 ′-(1,1-cyclohexylidene) [1,1′-biphenyl] -2-ol, 4,
4'-cyclohexylidenebis [2-cyclohexylphenol], 5,5 '-(1-phenylethylidene)
[1,1′-biphenyl] -2-ol, and the like.

Examples of the formaldehyde generating substance include various substances that generate formaldehyde under resolving conditions, such as paraformaldehyde, trioxane and tetraoxane. Examples of the basic catalyst include sodium hydroxide, potassium hydroxide, and the like, and the amount of the basic catalyst is 0.6 to 1.1 equivalent to 1 equivalent of the hydroxy group of the bisphenol compound represented by the general formula (4). It is about 2 molar equivalents.

In the present invention, the other raw material of the general formula (3):

[0023]

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(Wherein R ⁵ and R ⁶ each independently represent a hydrogen atom, a hydrocarbon group having 1 to 4 carbon atoms, or a halogen atom).
o-cresol, m-cresol, p-cresol,
2,3-xylenol, 2,4-xylenol, 2,5
-Xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, p-ethylphenol, p-isopropylphenol, p-tert-butylphenol, p-chlorophenol, p-bromophenol and the like. . Of these, cresols and xylenols are preferable in consideration of reactivity and water resistance. These may be used alone or in combination of two or more.

The polyhydroxy compound represented by the general formula (1) of the present invention comprises a dimethylol compound of a bisphenol compound represented by the general formula (2) and a phenol represented by the general formula (3). It is produced by a heat reaction in the presence of an acid catalyst. The acid catalyst used here is not particularly limited, and any of various catalysts used for ordinary novolak resins can be used. Among them, oxalic acid is particularly preferred.

The amount of the phenol to be used in the dimethylol compound is 2 to 2 mole parts per dimethylol compound.
20 mole parts. The production method of the present invention suppresses the mutual condensation reaction between the methylol groups present in the dimethylol compound by using the excess phenols in this manner.
The purpose is to minimize the production of high molecular weight components higher than the core. The lower limit of the amount of the phenol used is determined in consideration of the fact that the content of the high molecular weight component of five or more nuclei in the obtained polyhydroxy compound tends to increase and the melt viscosity tends to increase. It is preferably at least 2.5 mol parts, more preferably at least 3 mol parts, per 1 mol part of the dimethylol compound. On the other hand, the upper limit of the amount of the phenol used is determined in consideration of the cost, and is preferably 10 mol parts or less, more preferably 6 mol parts or less, based on 1 mol part of the dimethylol compound. It is.

The above reaction conditions are appropriately determined in consideration of the reactivity between the dimethylol compound and phenols, and are usually at a temperature of about 50 to 100 ° C., preferably 80 to 100, usually for 1 to 6 hours. It is good to heat it to the extent. Also,
To remove ionic impurities present in the reaction product,
The reaction product may be washed several times with water.

Next, dehydration and demonomerization are performed. The demonomer is mainly for removing unreacted phenols. The method of demonomerization is not particularly limited, and may be performed according to a normal distillation operation. For example, any of vacuum distillation, thin film distillation, steam distillation, and vacuum steam distillation may be used. However, condensates of two or more nuclei can hardly be removed by demonomerization.

The target compound represented by the general formula (1) according to the production method is as follows:

[0030]

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(Wherein, R ^{1 to} R ⁶ are the same as described above).

The polyhydroxy compound thus obtained has a trinuclear content of 5% by weight or less, and has the general formula (1)
The content of the tetranuclear polyhydroxy compound represented by
0% by weight or more and polydispersity (Mw / Mn, Mw
Is a weight average molecular weight value, and Mn is a number average molecular weight value.)
It has a narrow molecular weight distribution width of 1.50 or less.

The polyhydroxy compound represented by the general formula (1) of the present invention or a reaction product containing the compound is useful as a curing agent for an epoxy resin, and includes various epoxy resins, a curing accelerator, and other additives. And the like to form an epoxy resin composition, which can be suitably used for applications such as sealing materials for electronic components, laminates, and powder coatings. Further, the polyhydroxy compound of the present invention can be used as a polyol component for polyurethane or a raw material for epoxy resin. Hereinafter, the epoxy resin composition containing the polyhydroxy compound, the polyfunctional epoxy resin, and the curing accelerator of the present invention will be described.

Various known polyfunctional epoxy resins can be used. For example, novolak resin type epoxy resins such as orthocresol novolak type epoxy resin and phenol novolak type epoxy resin; diglycidyl ethers such as bisphenol A and bisphenol F;
Glycidyl ester type epoxy resin obtained by reacting polybasic acids such as phthalic acid and dimer acid and epichlorohydrin; glycidylamine type epoxy resin obtained by reacting polyamines such as diaminodiphenylmethane and isocyanuric acid with epichlorohydrin Epoxy resin; linear aliphatic epoxy resin and alicyclic epoxy resin obtained by oxidizing an olefin bond with a peracid such as peracetic acid, and the like. One of these may be used alone, or two or more may be appropriately used. Can be used in combination.

Examples of the curing accelerator for accelerating the curing reaction between the polyfunctional epoxy resin and the polyhydroxy compound of the present invention include, for example, 1,8-diaza-bicyclo (5,4,0) undecene-7. , Triethylenediamine, benzyldimethylamine, triethanolamine,
Tertiary amines such as dimethylaminoethanol and tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-phenylimidazole, 2-phenyl-
Imidazoles such as 4-methylimidazole and 2-heptadecylimidazole; organic phosphines such as tributylphosphine, methyldiphenylphosphine, triphenylphosphine, diphenylphosphine and phenylphosphine; tetraphenylphosphonium tetraphenylborate and 2-ethyl-4 -Methylimidazole tetraphenylborate, N-methylmorpholine
And tetraphenylboron salts such as tetraphenylborate.

The above polyhydroxy compound, polyfunctional epoxy resin and curing accelerator are usually blended in the following proportions to prepare an epoxy resin composition. Usually, the polyhydroxy compound is used such that the hydroxyl equivalent of the polyhydroxy compound is 0.5 to 1.5 equivalent to 1 equivalent of the epoxy equivalent of the polyfunctional epoxy resin. The curing accelerator is used in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the polyfunctional epoxy resin.

In addition, the epoxy resin composition may contain a solvent, a filler, a release agent, a surface treatment agent, a flame retardant, and the like, if necessary. The epoxy resin composition is usually mixed by heating using a roll, a kneader or the like.

[0038]

【The invention's effect】

(1) According to the present invention, a polyhydroxy compound that can be used for various uses can be provided. (2) Further, the polyhydroxy compound obtained by the production method of the present invention is a resin having a tetranuclear compound as a main component and a narrow molecular weight distribution width, and has a higher melt viscosity than a conventional novolak resin having the same softening point. Is low. Therefore, it can exhibit very excellent characteristics as a curing agent for an epoxy resin. For example, when used as a molding material, the viscosity of the compound is reduced, a material having good flowability can be provided, and workability during molding is significantly improved. (3) The epoxy resin using the polyhydroxy compound of the present invention as a curing agent has a high Tg of a cured product obtained by curing the bisphenol skeleton due to the bisphenol skeleton of the polyhydroxy compound. In addition to being excellent in chemical properties, it is particularly excellent in heat resistance.

[0039]

EXAMPLES The present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples. Note that, in each example, all percentages are based on weight.

Example 1 After replacing the inside of a 5-liter flask equipped with a stirrer, a thermometer and a condenser with nitrogen gas, 1,106 g of 4,4 '-(1-methylethylidene) bis [2-methylphenol] was obtained.
(3.5 mol), 1134 g of orthocresol (10.
5 mol) and 8.0 g of oxalic acid, and the mixture was reacted at 95 ° C. for 4 hours under a nitrogen stream, then dehydrated under reduced pressure, dephenolized by steam distillation, and the phenol monomer content was 0.5% or less. To obtain 1590 g of the polyhydroxy compound of the present invention.

Example 2 In Example 1, the amount of orthocresol used was changed to 189
The reaction was carried out in the same manner as in Example 1 except that the amount was changed to 0 parts (17.5 mol) to obtain 1610 g of a polyhydroxy compound having a phenol monomer content of 0.5% or less.

Comparative Example 1 In a 1000 ml flask equipped with a stirrer, thermometer and cooler, 329 g (3.5 mol) of phenol, 37%
227 g (2.8 mol) of a formalin aqueous solution and 1.3 g of oxalic acid were added, and the mixture was refluxed for 3 hours under a nitrogen stream, dehydrated under reduced pressure, and dephenolized by steam distillation.
Hydroxyl equivalent of less than 0.5% unreacted phenol content 1
310 g of phenol novolak resin was obtained.

Table 1 shows the properties of the various polyhydroxy compounds obtained in Examples 1 and 2 and the phenol novolak resin obtained in Comparative Example 1. The softening point is determined by the ring and ball method. Each component content and polydispersity (Mw / M
n) is a column (TSK gel G-manufactured by Toyo Soda Co., Ltd.)
2000HxL and G-1000HxL are configured in series)
Is a high-performance liquid chromatograph (HLC
-8020), and the data processing was performed by CP-8000 manufactured by the company. The melt viscosity was measured by combining a small sample adapter with a B-type viscometer (manufactured by Tokyo Keiki Co., Ltd.) under the conditions of a sample amount of 11 g, HM type rotor No. 2, and 150 ° C.

[0044]

[Table 1]

As is clear from FIGS. 1 and 2, the polyhydroxy compound (FIG. 1) obtained in the present invention has a narrower molecular weight distribution than the phenol novolak resin obtained in the comparative example (FIG. 2). Moreover, it can be seen that a tetranuclear body is the main component.

(Test Example) Epoxy resin (ESCM195)
XL, manufactured by Sumitomo Chemical Co., Ltd., epoxy equivalent 198) 1
To 98 g, as a curing agent, the various polyhydroxy compounds obtained in Examples 1 and 2 above, the phenol novolak resin obtained in Comparative Example 1, and a curing accelerator DBU (1,8-diaza-bicyclo (5,4,0) ) Undecene-7) was blended in the ratio shown in Table 1 and cured at 175 ° C for 10 hours to obtain a plate-shaped test piece having a thickness of 2 mm. Table 2 shows the results of measuring the Tg of the obtained cured product. In addition, Tg was measured using Seiko Electronic Industries Co., Ltd. TMA120.

[0047]

[Table 2]

From the results shown in Table 2, it is recognized that the cured product of the epoxy resin composition using the polyhydroxy compound of the present invention has a high Tg (heat resistance).

[Brief description of the drawings]

FIG. 1 shows a high-performance liquid chromatographic analyzer for polyhydroxy compounds of Example 1 (HLC-8, manufactured by Toyo Soda Co., Ltd.)
020) is a graph showing the molecular weight distribution measured using the method.

FIG. 2 is a similar graph of the phenol novolak resin of Comparative Example 1.

[Explanation of symbols]

 14 Tetranuclear peak

Claims (4)

[Claims] 1. General formula (1): (Wherein, R ¹ and R ² each represent a hydrocarbon group having 1 to 9 carbon atoms, R ³ and R ^{4 each} represent a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, and R ⁵ and R ⁶ each represent Independently represents a hydrogen atom, a hydrocarbon group having 1 to 4 carbon atoms, or a halogen atom.). 2. General formula (2): (Wherein, R ¹ and R ² each represent a hydrocarbon group having 1 to 9 carbon atoms, and R ³ and R ^{4 each} represent a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms). The compound represented by the general formula (3): (Wherein, R ⁵ and R ⁶ each independently represent a hydrogen atom,
And represents a hydrocarbon group or a halogen atom. 2) to 20 parts by mole of a phenol represented by the general formula (1): (In the formula, R ^{1 to} R ⁶ are the same as described above.) A polyhydroxy compound containing 40% by weight or more of the polyhydroxy compound represented by the formula: 3. General formula (2): (Wherein, R ¹ and R ² each represent a hydrocarbon group having 1 to 9 carbon atoms, and R ³ and R ^{4 each} represent a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms). The compound represented by the general formula (3): (Wherein, R ⁵ and R ⁶ each independently represent a hydrogen atom,
And represents a hydrocarbon group or a halogen atom. A method for producing a polyhydroxy compound, comprising condensing 2 to 20 mol parts of a phenol represented by the formula (1) under acidic conditions, followed by dehydration and demonomerization. 4. An epoxy resin composition comprising the polyhydroxy compound according to claim 1 or 2, a polyfunctional epoxy resin, and a curing accelerator.