JP4585255B2 - Phenol aralkyl resin and method for producing the same - Google Patents

Description

  The present invention relates to a phenol aralkyl resin and a method for producing the same.

  Thermosetting resin compositions are excellent in heat resistance, impact resistance, crack resistance, moisture resistance, workability, and electrical properties, and are widely used in laminates, molding materials, mold materials, adhesive materials, casting materials, etc. It's being used. In particular, it is suitably used as a molding material for IC sealing.

  In recent years, there is a tendency for high heat resistance to be demanded in the fields of sealing materials and molding materials, and a method of increasing heat resistance by increasing the blending amount of inorganic filler and reducing organic binder has been adopted. In order to ensure the property, the organic binder is required to have fluidity so as to flow into the gaps of the inorganic filler.

  As such an organic binder, it has excellent heat resistance compared to ordinary phenol resins, and, like phenol resins, can react with epoxy resins and give thermosetting resin compositions. Attention has been focused on phenol aralkyl resins that can also be used as (Patent Documents 1 and 2).

  However, the phenol aralkyl resins described in Patent Documents 1 and 2 have a problem that the balance between heat resistance and fluidity is not sufficient because the contents of trimer and tetramer are low.

JP-A-6-116369 JP 2002-80567 A

  An object of this invention is to provide the manufacturing method which can manufacture such a phenol aralkyl resin excellent in the balance of heat resistance and fluidity | liquidity, and such a phenol aralkyl resin with a high yield.

That is, the method for producing a phenol aralkyl resin of the present invention comprises phenols and 0.5 to 0.85 mol of an aralkyl compound represented by the following general formula (1) per mol of phenol, phosphoric acid and The phenol aralkyl resin of the present invention is characterized by having a heterogeneous reaction in the presence of a non-reactive oxygen-containing organic solvent (excluding methanol, acetone, butanol, and propanol) as a reaction auxiliary solvent . A phenol aralkyl resin produced by the production method, wherein the total content of the trimer component and the tetramer component is 35% or more as measured by an area method of gel filtration chromatography.

（式中、Ｒ、Ｒ’は、Ｈまたは炭素数が１〜６のアルキル基を示し、それぞれ異なっていても良く、同一であっても良い。）

(In the formula, R and R ′ represent H or an alkyl group having 1 to 6 carbon atoms, which may be different or the same.)

  The phenol aralkyl resin of the present invention has a high content of trimers and tetramers, and is excellent in the balance between heat resistance and fluidity.

  In addition, the production method of the present invention has high content of trimer and tetramer, unreacted monomer having high volatility and deteriorating working environment, dimer and fluidity that hardly contribute to improvement of heat resistance. A phenol aralkyl resin having a low content of a high-order condensate that hardly contributes to improvement and an excellent balance between heat resistance and fluidity can be produced in a high yield. Moreover, the production method of the present invention can produce a phenol aralkyl resin having a high reaction selectivity and a high para bond rate.

  The phenol aralkyl resin of the present invention has a total content of a trimer component and a tetramer component of 35% or more, preferably 40% or more, as measured by an area method of gel filtration chromatography. If the total content of the trimer component and the tetramer component is 35% or more, it is excellent in heat resistance and good in fluidity because it is easy to perform three-dimensional crosslinking during curing.

In the phenol aralkyl resin of the present invention, the ortho / para bond ratio of the methylene group is preferably 0.46 or less, more preferably 0.44 or less, and further preferably 0.43 or less. Here, the ortho / para bond ratio is the ratio (ortho bond / para bond) between the number of ortho-bonded methylene groups and the number of para-bonded methylene groups, which indicates the bonding position of the methylene group to the phenolic hydroxyl group, measured by ¹³ C-NMR. Value. If the ortho / para bond ratio exceeds 0.46, the ratio of the ortho bond of the methylene group increases, resulting in steric hindrance blocked by bulky aralkyl groups, and epoxidation when used as a raw material for epoxy resins. The reaction may be inhibited, and when used as a curing agent for an epoxy resin, the reaction with an epoxy group may be inhibited.

  Moreover, it is preferable that content of a dimer component is 35% or less by measurement by the area method of a gel filtration chromatograph, More preferably, it is 30% or less. The dimer has only two reactive sites and cannot be three-dimensionally crosslinked during curing. If the content of such a dimer component exceeds 35%, the heat resistance may not be sufficient. There is.

  Furthermore, 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 1.7 or less, more preferably 1.5 or less, More preferably, it is 1.3 or less. If the dispersion ratio (Mw / Mn) exceeds 1.7, it may be impossible to achieve both heat resistance and fluidity.

  The production method of the present invention capable of producing such a phenol aralkyl resin in a high yield requires phenols and an aralkyl compound as raw materials, and phosphoric acids as an acid catalyst, and mechanically stirs the two-phase separation state formed therefrom. In a heterogeneous reaction system of white turbidity in which two phases (organic phase and aqueous phase) are mixed by mixing with ultrasonic waves, etc., the reaction between phenols and aralkyl compounds proceeds to synthesize a condensate (resin). To do.

  Examples of phenols used as a reaction raw material include phenol, m-cresol, p-cresol, o-cresol, 2,3-xylenol, 2,5-xylenol, 3,5-xylenol, and 3,4-xylenol. Xylenols, m-ethylphenol, p-ethylphenol, o-ethylphenol, 2,3,5-trimethylphenol, 2,3,5-triethylphenol, 4-tert-butylphenol, 3-tert-butylphenol, 2- alkylphenols such as tert-butylphenol, 2-tert-butyl-4-methylphenol, 2-tert-butyl-5-methylphenol, 6-tert-butyl-3-methylphenol, p-methoxyphenol, m-methoxyphenol P-Ethoxy Alkoxyphenols such as enol, m-ethoxyphenol, p-propoxyphenol, m-propoxyphenol, o-isopropenylphenol, p-isopropenylphenol, 2-methyl-4-isopropenylphenol, 2-ethyl-4- Examples thereof include isopropenylphenols such as isopropenylphenol, polyhydroxyphenols such as 4,4′-dihydroxybiphenyl, bisphenol A, phenylphenol, resorcinol, hydroquinone and pyrogallol.

  The phenols are not limited to the above examples, and may be used alone or in combination of two or more. In the case of producing a phenol aralkyl resin having an ortho / para bond ratio of 0.46 or less, the proportion of phenols having a substituent at the para-position to the hydroxyl group in the total phenols is 15% by mass or less. It is preferable to do this.

  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.

  The aralkyl compound used as a reaction raw material is represented by the following general formula (1).

（式中、Ｒ、Ｒ’は、Ｈまたは炭素数が１〜６のアルキル基を示し、それぞれ異なっていても良く、同一であっても良い。）

(In the formula, R and R ′ represent H or an alkyl group having 1 to 6 carbon atoms, which may be different or the same.)

  Specifically, for example, aralkyl alcohol such as α, α′-dihydroxy-p-xylene, α, α′-dihydroxy-m-xylene, α, α′-dihydroxy-o-xylene, α, α′-dimethoxy -P-xylene (PXDM), α, α'-dimethoxy-m-xylene, α, α'-dimethoxy-o-xylene, α, α'-diethoxy-p-xylene, α, α'-diethoxy-m- Xylene, α, α'-diethoxy-o-xylene, α-hydroxy-α'-methoxy-p-xylene, α-hydroxy-α'-methoxy-m-xylene, α-hydroxy-α'-methoxy-o- Xylene, α-ethoxy-α'-hydroxy-p-xylene, α-ethoxy-α'-hydroxy-m-xylene, α-ethoxy-α'-hydroxy-o-xylene, α-ethoxy-α'-methoxy Examples include aralkyl ethers such as cis-p-xylene, α-ethoxy-α′-methoxy-m-xylene, α-ethoxy-α′-methoxy-o-xylene, and among these, α, α′-dimethoxy -P-xylene (PXDM) is preferred.

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

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

  The compounding ratio of phenols to aralkyl compounds (phenols / aralkyl compounds) is 0.5 to 0.85, preferably 0.55 to 0.7 on a molar basis. When the blending ratio is less than 0.5, it is difficult to reduce the content of components below the dimer, and conversely when it exceeds 0.85, the content of trimer and tetramer decreases.

  Phosphoric acids used as a reaction catalyst play an important role in forming a phase separation reaction (heterogeneous reaction) between phenols and aralkyl compounds. Examples of such phosphoric acids include, for example, Examples thereof include polyphosphoric acid such as metaphosphoric acid, pyrophosphoric acid, orthophosphoric acid, triphosphoric acid, and tetraphosphoric acid, phosphoric anhydride, and a mixture thereof. An orthophosphoric acid aqueous solution that is easily available at a low cost, for example, 75% by mass phosphoric acid. 89 mass% phosphoric acid is generally used.

  The blending amount of phosphoric acids is preferably 40 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 50-300 mass parts, More preferably, it is 60-200 mass parts. When the blending amount is less than 40 parts by mass, the production of a high molecular weight component is promoted, while the low molecular weight component, particularly the 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.

  From the viewpoint of promoting the phase separation reaction, it is preferable to use a non-reactive oxygen-containing organic solvent as a reaction auxiliary solvent. 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, diethylene glycol, dipropylene glycol, triethylene glycol, and triethylene glycol. Examples thereof include dihydric alcohols such as propylene glycol and 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 sulfoxides include dimethyl sulfoxide (DMSO) and diethyl sulfoxide.

  Among these, methanol, ethylene glycol monobutyl ether, ethylene glycol, polyethylene glycol, 1,4-dioxane, dimethyl sulfoxide 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.

  The blending amount of the reaction auxiliary solvent is preferably 5 to 1000 parts by mass and more preferably 20 to 500 parts by mass with respect to 100 parts by mass of the phenols. 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.

  In the production method of the present invention, from the viewpoint of the phase separation effect, the water content in the system is preferably 30% 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 70 ° 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.

  After completion of the reaction, it is preferable to have a washing step. Specifically, a water-insoluble organic solvent (for example, methyl ethyl ketone, methyl isobutyl ketone, etc.) is added and mixed to dissolve the condensate (phenol aralkyl resin), and then allowed to stand to leave an organic layer (a water-insoluble organic solvent, condensation) And a water layer (including a reaction cosolvent and phosphoric acids). Next, after removing the aqueous layer from the system, the phosphoric acids and the reaction auxiliary solvent are recovered, while the organic layer is washed with hot water and / or neutralized, and then the water-insoluble organic solvent is removed by distillation under reduced pressure.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not a thing limited at all by these examples. In the examples, “parts” and “%” indicate “parts by mass” and “% by mass” unless otherwise specified.

  The obtained phenol aralkyl resin was measured by the following test method. The yield of the phenol aralkyl resin was expressed as a percentage (mass basis) with respect to the theoretical yield of the phenol aralkyl resin.

(1) Weight average molecular weight (Mw), number average molecular weight (Mn), dispersity (Mw / Mn)
Measurement of Tosoh Corporation GPC (gel filtration chromatograph SC-8020, column (TSKgel): G2000H _XL + G4000H _XL , detector UV-8011 (λ: 254 nm), carrier: tetrahydrofuran 1 ml / min, column temperature: 38 ° C.) By calculating the weight average molecular weight (Mw) and the number average molecular weight (Mn) in terms of standard polystyrene, the degree of dispersion (Mw / Mn) is calculated, and a value close to 1.00 means that the resin has a narrow molecular weight distribution. evaluated.

(2) Molecular weight distribution Calculated by the area method that displays the area of dimer, trimer, tetramer, and higher-order condensate (pentamer or higher) as a percentage of the total area of the molecular weight distribution obtained by GPC measurement. The content of each component was determined.

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

(4) Cone plate melt viscosity (Pa · s / 150 ° C)
It was measured with a cone plate melt viscometer (CON PLATE VISCOMETER MODEL CV-1 manufactured by Toa Kogyo Co., Ltd.).

(5) Ortho / para bond ratio ¹³ C-NMR (100 MHz, solvent: deuterated methanol-d4) was measured using a nuclear magnetic resonance apparatus (manufactured by Varian: INOVA 400), and calculated according to the following formula.
Ortho / para bond ratio = (a + 1/2 × b) / (c + 1/2 × b)
a: integral value of ortho-ortho bond methylene absorption band (29.6-33.2 ppm) b: integral value of ortho-para bond methylene absorption band (34.3-38.5 ppm) c: para-para bond methylene absorption Integrated value of band (39.5-42.9ppm)

<Example 1 (reference example) >
In a reaction vessel equipped with a thermometer, a stirrer and a reflux condenser, 94 parts of phenol (P) and 116 parts of α, α′-dimethoxy-p-xylene (PXDM) (molar basis: PXDM / P = 0) 70) and 94 parts (100% / P) of 89% phosphoric acid, and then heated to 120 ° C. under a cloudy state (two-phase mixture) formed by stirring and mixing. After 10 hours of condensation reaction, the reaction was stopped.

  Next, methyl isobutyl ketone is added with stirring and mixing to dissolve the condensate, and stirring is stopped and the contents are transferred into a separatory flask and allowed to stand, and the methyl isobutyl ketone solution phase (upper phase) and phosphorus are mixed. Separated into aqueous acid phase (lower phase). Next, the phosphoric acid aqueous solution phase is removed, and the methyl isobutyl ketone solution phase is washed 5 times with water to remove phosphoric acid. Then, the contents are returned to the reaction vessel again, and methyl isobutyl ketone is completely removed by distillation under reduced pressure. 157 parts of phenol aralkyl resin (theoretical yield 95%) were obtained.

  About the obtained phenol aralkyl resin, the resin characteristic was measured by the test method described at the beginning. The results are shown in Table 1. Moreover, the GPC chart of the obtained phenol aralkyl resin is shown in FIG.

<Examples 2-3 (Example 3 is a reference example) >
A phenol aralkyl resin was obtained and measured in the same manner as in Example 1 except that the reaction conditions were changed as shown in Table 1. The results are shown in Table 1.

  In the same reaction vessel as in Example 1, 94 parts of phenol (P), 116 parts of PXDM (molar basis: PXDM / P = 0.70), 0.1 part of diethyl sulfate (0.5% / P ), The temperature was gradually raised to 140 ° C., and a condensation reaction was carried out at the same temperature for 6 hours. Subsequently, normal pressure dehydration and subsequent dehydration under reduced pressure yielded 131 parts of phenol aralkyl resin (theoretical yield 79%).

  About the obtained phenol aralkyl resin, the resin characteristic was measured by the test method described at the beginning. The results are shown in Table 1. Moreover, the GPC chart of the obtained phenol aralkyl resin is shown in FIG.

<Comparative example 2>
In the same reaction vessel as in Example 1, 94 parts of phenol (P), 116 parts of PXDM (molar basis: PXDM / P = 0.70), 70 of 1-hydroxyethylidene-1,1′-diphosphonic acid After charging part (60% / P), the mixture was heated to 170 ° C. under a cloudy state (two-phase mixture) formed by stirring and mixing, and further subjected to a condensation reaction at the same temperature for 9 hours. Subsequently, normal pressure dehydration and subsequent dehydration under reduced pressure gave 152 parts of phenol aralkyl resin (theoretical yield: 92%).

  About the obtained phenol aralkyl resin, the resin characteristic was measured by the test method described at the beginning. The results are shown in Table 1. Moreover, the GPC chart of the obtained phenol aralkyl resin is shown in FIG.

2 is a GPC chart of phenol aralkyl resin obtained in Example 1. FIG. 2 is a GPC chart of a phenol aralkyl resin obtained in Comparative Example 1. 3 is a GPC chart of a phenol aralkyl resin obtained in Comparative Example 2.

Explanation of symbols

1 Dimer component (peak that seems to be a structure in which two molecules of phenol are cross-linked with one molecule of an aralkyl compound represented by the general formula (1))
2 Trimer component (peak which seems to be a structure in which 3 molecules of phenol are cross-linked with 2 molecules of aralkyl compound represented by general formula (1))
3 Tetramer component (peak which seems to be a structure in which 4 molecules of phenol are cross-linked with 3 molecules of aralkyl compound represented by general formula (1))
4 Higher-order condensate (peak that seems to be a structure in which 5 or more molecules of phenol are cross-linked with 4 or more molecules of aralkyl compound represented by general formula (1))

Claims (7)

A non-reactive oxygen-containing organic solvent (a non-reactive oxygen-containing organic solvent as a reaction auxiliary solvent ) containing phenols and 0.5 to 0.85 mol of an aralkyl compound represented by the following general formula (1) with respect to 1 mol of phenols However, a method for producing a phenol aralkyl resin, comprising a step of causing a heterogeneous reaction in the presence of methanol, acetone, butanol and propanol) .

(In the formula, R and R ′ represent H or an alkyl group having 1 to 6 carbon atoms, which may be different or the same.) The method for producing a phenol aralkyl resin according to claim 1 , wherein the aralkyl compound is α, α'-dimethoxy-p-xylene. The reaction cosolvent is an alcohol, a polyhydric alcohol ethers, cyclic ethers, polyhydric alcohol esters, ketones, claim 1 or 2, characterized in that at least one selected from the group consisting of sulfoxides The manufacturing method of phenol aralkyl resin as described in any one of. It is phenol aralkyl resin manufactured by the manufacturing method of any one of Claims 1-3 , Comprising: The total content of a trimer component and a tetramer component by the measurement by the area method of a gel filtration chromatograph Is a phenol aralkyl resin, characterized by being 35% or more. 5. The phenol aralkyl resin according to claim 4 , wherein an ortho / para bond ratio of the methylene group is 0.46 or less. 6. The phenol aralkyl resin according to claim 4 or 5 , wherein the content of the dimer component is 35% or less as measured by an area method of gel filtration chromatography. The dispersion ratio (Mw / Mn) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) as measured by gel filtration chromatography is 1.7 or less, or any one of claims 4 to 6 , Phenol aralkyl resin.

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