JP2003327554A - 3,3',5,5'-tetramethyl-4,4'-biphenol and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide 3,3',5,5'-tetramethyl-4,4'-biphenol affording an epoxy resin having good characteristics with suppressed side reactions in a reaction with an epihalohydrin (a reaction for producing the epoxy resin) and especially suitable for industrial use as a resin raw material used in the fields of electronic and electrical materials or a raw material for resin intermediates. <P>SOLUTION: The 3,3',5,5'-tetramethyl-4,4'-biphenol has ≤0.7 wt.ppm of copper content and 0.01-1.0 wt.% of 2,6-xylenol content. The 3,3',5,5'-tetramethyl-4,4'- biphenol is obtained by oxidizing and dimerizing the 2,6-xylenol in the presence of a metal catalyst in an alkaline aqueous solution containing a surfactant. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to 3, 3 ', 5,
Regarding 5'-tetramethyl-4,4'-biphenol (hereinafter referred to as "TMBPL") and a method for producing the same, specifically, TMBPL suitable for industrial use as a resin raw material or a raw material of a resin intermediate, and The manufacturing method is related.

TMBPL is a compound useful as a raw material for epoxy resins, polyester resins, polycarbonate resins and the like, and as a raw material for stabilizers and plasticizers for petroleum products. In particular, the epoxy resin using TMBPL as a raw material is useful in the electric and electronic fields.

[0003]

2. Description of the Related Art TMBPL is obtained by oxidative dimerization of 2,6-xylenol in the presence of a metal catalyst in an alkaline aqueous solvent containing a surfactant (see, for example, JP-A-53).
-65834 and JP-A-60-152433).

By the way, TMBPL can be obtained in a relatively high yield by the above method, but requires a complicated purification step. That is, tetramethyldiphenoquinone (hereinafter referred to as “DPQ”), which is a by-product of the reaction, is contained in the reaction solution.
-(2,6-dimethylphenoxy) -2,6-dimethylphenol (hereinafter referred to as "ED"), polyphenylene ether and oligomers thereof (hereinafter referred to as "PPE"),
It contains unreacted 2,6-xylenol (hereinafter referred to as "XNL"), a catalyst, an alkali metal or alkaline earth metal, a copper compound, a surfactant and the like.

However, when TMBPL is reacted with epihalohydrin to produce an epoxy resin, the above-mentioned components (impurities) increase side reactions to reduce the yield and deteriorate the characteristics of the produced epoxy resin. Sometimes. Further, impurities remaining in the epoxy resin may deteriorate the heat resistance and electrical characteristics of the final product. Therefore,
There is an increasing demand for high-purity TMBPL.

[0006] Conventionally, as a method for obtaining high-purity TMBPL, after the reaction is completed, a slurry of TMBPL is filtered off, followed by washing with water to remove the surfactant and inorganic substances, washing with an organic solvent, filtration and drying. (JP-A-53-65834, JP-A-2-1418, etc.) are known.
Also, as a method for removing DPQ, Japanese Patent Laid-Open No. 61-2686
No. 41 discloses heat treatment in an inert gas atmosphere after completion of the reaction, and Japanese Patent No. 2861221 further adjusts pH after the reaction to 7.0 or less, water after heat treatment. It is described that organic impurities can be reduced by adding / lower alcohol and mixing and stirring. However, although these methods can reduce organic impurities, they cannot sufficiently reduce metal impurities.

On the other hand, the crude T was prepared by the recrystallization method using various mixed solvents.
A method for purifying MBPL is also disclosed (Japanese Patent Publication No. 8-
19020, 8-30019). However, in such a method, there are problems that a complicated step is added and the recovery rate is low.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is an epoxy resin having good properties in which side reactions are suppressed in the reaction with epihalohydrin (epoxy resin production reaction). Which is suitable for industrial use as a resin raw material or a resin intermediate raw material used in the field of electrical and electronic materials.
And to provide an industrially advantageous manufacturing method thereof.

[0009]

As a result of intensive studies, the present inventor has found that TMB does not require a special and complicated purification step.
It was found that the above object can be easily achieved by reducing the content of a specific impurity in PL to a specific range. Further, it was found that a specific impurity in TMBPL causes a favorable reaction when the epoxy resin is produced by reacting with epihalohydrin.

The present invention has been achieved on the basis of the above findings, and the first gist thereof is that the content of copper is 0.7 wt ppm or less and the content of 2,6-key-silenol is 0.01.
3,3 ′, 5, characterized in that
It exists in 5'-tetramethyl-4,4'-biphenol.

The second gist of the present invention is to add 0.005-0.04 mmol (value per mol of 2,6-xylenol) of 2,6-xylenol in an alkaline aqueous solvent containing a surfactant. Oxidative dimerization in the presence of a metal catalyst, the obtained reaction solution is heated while maintaining pH 7 or less, and water and unreacted 2,6-xylenol are distilled off,
After acid is added to the obtained liquid product to adjust the pH to 2.5 to 5, alcohol is added and mixed and stirred, and the resulting liquid mixture is subjected to solid-liquid separation to obtain 3,3 ', 5,5'-. Tetramethyl-4,
Recovering 4'-biphenol, 3,
It exists in a method for producing 3 ′, 5,5′-tetramethyl-4,4′-biphenol.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
First, for convenience of description, a method of manufacturing the TMBPL of the present invention will be described.

First, in the present invention, 2,6-xylenol (X
NL) is oxidatively dimerized in the presence of 0.005-0.04 mmol of metal catalyst.

The amount of water used as a reaction solvent is XNL.
It is usually 100 to 1000 ml, preferably 100 to 500 ml per mol. Examples of the surfactant include fatty acid soap, alkyl sulfonate, alkylbenzene sulfonic acid, alkyl sulfate and the like. The amount of the surfactant used is usually 0.1 per mol of XNL.
The range is ˜50 mmol.

Examples of the alkaline substance include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alkali metal carbonates such as sodium carbonate, hydrogen carbonates, boron compounds such as sodium borate and borax, and phosphorus. Examples thereof include alkali metal phosphates such as sodium acidate, sodium hydrogenphosphate, potassium phosphate, potassium hydrogenphosphate, and amine bases such as triethylamine and pyridine. Among these, a boron compound is preferable in terms of yield and selectivity. The amount of the alkaline substance used is usually such that the pH of the reaction system is maintained in the range of 8 to 11.

A copper compound is preferably used as the metal catalyst. The copper compound may be either monovalent or divalent,
Specific examples thereof include copper halide, copper hydroxide, copper sulfate, copper nitrate, copper carboxylate, copper alkylsulfate and the like. The amount of the metal catalyst used is 0.005 to 0.04 m
mol (value per 1 mol of XNL). When the amount of the metal catalyst used is less than 0.005 mmol, the catalytic action is sufficiently expressed, and when the amount exceeds, the content in the reaction solution is high,
A great load is applied to the refining process for reducing the content in TMBPL. The amount of the metal catalyst used (value per 1 mol of XNL) is preferably in the range of 0.01 to 0.04 mmol.

As the oxidant, oxygen-containing gas such as air is used in addition to oxygen gas. Reaction temperature is usually 50 to 1
The reaction pressure of 00 ° C. depends on the oxygen concentration in the gas phase, but it is sufficient that it is in the range of atmospheric pressure to 30 atmospheres. Reaction time is usually 5
~ 15 hours. The resulting reaction liquid is generally an aqueous slurry.

Next, in the present invention, the obtained reaction solution is heated while maintaining the pH at 7 or less, and water and unreacted XNL are distilled off. In this case, it is preferable to adjust the pH after replacing the inside of the reaction system with an inert gas such as nitrogen. The pH adjustment is important for preventing the inclusion of inorganic impurities in the product TMBPL. The acid used for pH adjustment is not particularly limited, but a mineral acid is generally used. Particularly, sulfuric acid or hydrochloric acid is preferable.

By distilling off the water and the unreacted XNL (distillation recovery), DPQ in the TMBPL and the unreacted XNL are removed.
Can be reduced. In this case, the allowable amount of XNL remaining in TMBPL is usually about 10% by weight, preferably 3% by weight or less. Water and unreacted X
If the pH during the distillation of NL exceeds 7.0, T
The amount of heavy impurities (PPE) in MBPL increases. After distilling off water and unreacted XNL, the obtained reaction slurry may be filtered to collect crude TMBPL as a solid, which may be used in the next step.

Next, in the present invention, an acid is added to the resulting product solution to adjust the pH to 2.5 to 5, preferably 3 to.
After adjusting to 4.5, alcohol is added and mixed and stirred. The above pH adjustment is important for reducing the copper content in TMBPL. As the alcohol, lower alcohols having 1 to 4 carbon atoms such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol and n-butanol are preferably used. In this case, the weight ratio of water / alcohol is usually 5/5 to 8/2, preferably 6/4 to 7/3.
Is. Entrained water from the reaction slurry is used for the preparation of such a mixed solution, but water is added when the crude TMBPL is recovered as a solid.

By setting the mixing ratio of water and alcohol within the above range, the solubility of TMBPL can be lowered and the recovery rate thereof can be maintained high, and the solubility of impurities to be removed can be maintained sufficiently high. TMBP in the mixture
The concentration of L is usually 5 to 50% by weight. The temperature at the time of mixing and stirring is usually 40 to 100 ° C., preferably 50 to 90.
℃. There is no problem even if undissolved TMBPL remains. The time for mixing and stirring is usually 0.1 to 5 hours, preferably 0.5 to 3 hours.

Then, in the present invention, the obtained mixed liquid is subjected to solid-liquid separation to obtain 3,3 ', 5,5'-tetramethyl-
Recover 4,4'-biphenol (TMBPL). Means such as filtration and centrifugation are adopted for solid-liquid separation. The temperature of the mixed liquid at the time of solid-liquid separation is usually 35 to 70 ° C, preferably 40 to 65 ° C. If the temperature is too high, the organic impurities are easily removed, but the yield of TMBPL is lowered, and if the temperature is too low, the content of organic impurities is increased.

Next, the 3,3 ', 5,5'-tetramethyl-4,4'-biphenol (TMBPL) of the present invention will be described. The TMBPL of the present invention has a copper content of 0.7 ppm by weight or less and 2,6-key-silenol (XN
The content of L) is 0.01 to 1.0% by weight.

Copper content is preferably 0.6 ppm by weight
It is below (usually the lower limit is 0.1 ppm), and the XNL content is preferably 0.01 to 0.9% by weight. When the content of copper is more than 0.7 wt ppm or the content of XNL is more than 1.0 wt%, side reactions are increased in the reaction with epihalohydrin (epoxy resin production reaction), which leads to good properties. Epoxy resin cannot be obtained. on the other hand,
To reduce the content of impurities more than necessary, an extra refining step is required, which is industrially disadvantageous. In the present invention, the content of DPQ is 0.001 to 0.1% by weight.
Is preferred. The TMBPL of the present invention is preferably used as a raw material for producing an epoxy resin which is reacted with epihalohydrin. The reaction of TMBPL with epihalohydrin is optionally carried out in the presence of an inert solvent.

[0025]

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited to the following examples unless it exceeds the gist. In addition, "%" described below indicates "% by weight". The analysis of each component was performed as follows.

(1) Copper analysis: Quantitative analysis was carried out by inductively coupled plasma emission spectrometry (ICP-AES method). Measurement wavelength is 32
The measurement sample was prepared by the following method. That is, 2 g of a dried sample was added to 20 ml of a 0.5 mol / L hydrochloric acid solution, vigorously shaken for 1 minute to dissolve it, allowed to stand for 1 minute and then filtered through a filter paper of 5A, and the obtained filtrate was used as a measurement sample. .

(2) Analysis of XNL and ED: quantified by gas chromatography. A phenylmethyl silicone capillary column with a degree of crosslinking of 5% (“CBP-5” manufactured by J & W) is used as a column, a flame ionization detector (FID) is used as a detector, and diphenyl is used as an internal standard substance, and a measurement sample is acetone. The sample was prepared by dissolving 2 g of the sample in 25 ml.

(3) Analysis of DPQ: Quantitatively determined by spectrophotometry. The cell length is 10 mm, the measurement wavelength is 420 nm,
The measurement sample was prepared by adjusting the volume of 0.5 g of the sample to 100 ml of chloroform.

(4) PPE analysis: quantified by liquid chromatography. For the molecular sieve column, Showa Denko KK "SHO
DEX KF-801 "(excretion limit molecular weight: about 150
0), tetrahydrofuran as a carrier (mobile phase),
A UV detector (268 nm) was used as a detector, and benzene was used as an internal standard substance. The measurement sample was prepared by dissolving 50 mg of the sample in 5 ml of tetrohydrofuran.

Example 1 A stainless steel reactor with a baffle plate of 30 L was charged with XNL4k.
g, borax 400 g, sodium lauryl sulfate 13 g,
12 kg of water and 0.2 g of cupric acetate were charged, and the temperature was raised while heating with stirring. When the temperature of the contents reached 70 ° C, introduction of oxygen was started. Stirring is continued so that the reaction temperature is kept at 70 ° C., and after 12 hours, introduction of oxygen is stopped,
The inside of the reaction system was purged with nitrogen.

Then, 25% sulfuric acid was added to adjust the pH of the resulting slurry to 6.5, and then the temperature was gradually raised to carry out distillation to distill water and unreacted XNL in a total amount of 5.3 kg. It was Then, cool the temperature in the reactor to 70 ° C., and
% Sulfuric acid was added to adjust the pH of the reaction solution to 3.8, 1.75 kg of water and 6.05 kg of isopropyl alcohol were added, and the mixture was stirred for 30 minutes while controlling at 60 ° C. The concentration of water in the obtained slurry was 63%.

Thereafter, the temperature was maintained at 60 ° C., the obtained slurry was treated with a centrifuge for solid-liquid separation, and hot water at 60 ° C. for 5 k
The solids in the centrifuge were rinsed with g. When the obtained solid was dried with a vacuum dryer, 3.0 kg of TMB was obtained.
PL was obtained.

The analysis results of each impurity in TMBPL are as follows.
Copper: 0.6 ppm, XNL: 0.60%, ED: 0.0
5%, DPQ: 0.06%, PPE: 0.28%.

Comparative Example 1 A stainless steel reactor with a baffle plate of 30 L was charged with XNL4k.
g, 400 g of borax, 13 g of sodium lauryl sulfate and 12 kg of water were charged, and the temperature was raised with heating while stirring. When the temperature of the contents reached 70 ° C, cupric acetate 0.
3 g was added and the introduction of oxygen was started. Reaction temperature is 75
Stirring was continued while maintaining the temperature at 0 ° C., introduction of oxygen was stopped after 8 hours, and the reaction system was purged with nitrogen.

Thereafter, 25% sulfuric acid was added to adjust the pH of the resulting slurry to 6.5, and then the temperature was gradually raised to distill the water and the unreacted 2,6-xylenol was added to a total of 5.
3 kg was distilled. Then, the temperature in the reactor was cooled to 70 ° C., 1.75 kg of water and 6.05 kg of isopropyl alcohol were added, and the temperature was adjusted to 60 ° C. to 30 ° C.
Stir for minutes. Then, 25% sulfuric acid was added to adjust the pH of the system to 5.5, and the system was cooled to 30 ° C. The concentration of water in the solvent at this time was 65%.

The resulting slurry was subjected to solid-liquid separation by a centrifugal separator, and the solid in the centrifugal separator was rinsed with 5 kg of warm water. When the obtained solid was dried with a vacuum dryer,
3.3 kg of TMBPL was obtained.

The analysis results of each impurity in TMBPL are as follows:
Copper: 2 ppm, XNL: 0.45%, ED: 0.1%,
DPQ was 0.05% and PPE was 0.30%.

Reference Examples 1 and 2 121 g of each TMBPL obtained in the above-mentioned Example 1 and Comparative Example 1 and epichlorohydrin were placed in a 2-necked three-necked flask equipped with a thermometer, a stirrer and a condenser. 555 g
And isopropyl alcohol 200g are charged, and 50
After the temperature was raised to 0 ° C., 91 g of a 48.5% aqueous sodium hydroxide solution was added dropwise with stirring over 1 hour. During that time, the temperature was gradually raised so that the temperature in the system became 70 ° C. at the end of the dropping. Then, the reaction was carried out by holding at 70 ° C. for 30 minutes. After completion of the reaction, it was washed with water to remove the by-product salt and excess sodium hydroxide. Then, excess epichlorohydrin and isopropyl alcohol were distilled off from the product under reduced pressure to obtain an epoxy resin composition.

The above epoxy resin composition was dissolved in 250 g of methyl ethyl ketone, 2 g of a 48.5% aqueous sodium hydroxide solution was added, and the mixture was reacted at a temperature of 70 ° C. for 1 hour. After completion of the reaction, sodium phosphate monobasic was added to neutralize excess sodium hydroxide, and by-product salts were removed. Then, the insoluble matter was filtered off, and then methyl ethyl ketone was completely removed under reduced pressure to obtain an intended epoxy resin composition. Table 1 shows the epoxy equivalent, melt viscosity and yield of each epoxy resin composition. The melt viscosity was measured at a temperature of 150 ° C. using an ICI viscometer (cone plate type rotational viscometer).

[0040]

[Table 1]

In Reference Example 1, an epoxy resin composition having an epoxy performance suitable as an electronic material was obtained. In Reference Example 2, the yield of the epoxy resin composition was low.
The epoxy performance of this epoxy resin composition was unsuitable as an electronic material.

[0042]

According to the present invention described above, side reactions are suppressed in the reaction with epihalohydrin (epoxy resin production reaction), and an epoxy resin having good characteristics is obtained,
Particularly suitable for industrial use as a resin raw material or a raw material of a resin intermediate used in the field of electric and electronic materials.
3 ', 5,5'-Tetramethyl-4,4'-biphenol is provided.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4H006 AA01 AA02 AB46 AC23 AD11                       AD17 BA05 BA29 BA32 BA34                       BA36 BA37 BA73 BB14 BB31                       BC16 BC17 BE30 FC52 FE13                 4H039 CA41 CD10                 4J036 AD04 AD07 BA01

Claims (4)

[Claims] 1. A copper content of 0.7 ppm by weight or less,
Content of 2,6 ky- silenol is 0.01-1.0 weight%, 3,3 ', 5,5'- tetramethyl- 4,4'-biphenol. 2. The composition according to claim 1, wherein the content of tetramethyldiphenoquinone is 0.001 to 0.1% by weight.
3 ', 5,5'-tetramethyl-4,4'-biphenol. 3. The 3,3 ′ according to claim 1, which is a raw material for producing an epoxy resin to be reacted with epihalohydrin,
5,5'-Tetramethyl-4,4'-biphenol. 4. 2,5-xylenol is added in an alkaline aqueous solvent containing a surfactant in an amount of 0.005 to 0.04 mm.
ol (value per 1 mol of 2,6-xylenol) is oxidized and dimerized in the presence of a metal catalyst, and the resulting reaction solution is adjusted to pH.
Heating while maintaining at 7 or less, water and unreacted 2,6-
Xylenol was distilled off, and acid was added to the resulting product solution to adjust the pH to 2.5 to 5, then alcohol was added and mixed and stirred, and the resulting mixed solution was subjected to solid-liquid separation to obtain 3,3 ′. , 5,
A method for producing 3,3 ′, 5,5′-tetramethyl-4,4′-biphenol, which comprises recovering 5′-tetramethyl-4,4′-biphenol.