JP2004018698A - Method for manufacturing phenol resin - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for efficiently manufacturing a phenol resin suitable for a resin composition for use in a laminate. <P>SOLUTION: According to this method for manufacturing a phenol resin, a phenol is reacted with a butadiene (co)polymer in the presence of an acid catalyst, wherein they are contacted with each other to make a single homogeneous phase for the reaction. A phenol-added butadiene (co)polymer can be efficiently manufactured, while suppressing gelled by-products formation, as a phenol resin suitable for a resin composition for use in a laminate excellent in electric properties such as dielectric constant and dielectric dissipation factor, high glass transition temperature, and also excellent in other properties such as heat resistance, moisture resistance and flame retardancy. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for producing a phenol resin suitable for a resin composition for a laminate used for a printed wiring board having glass cloth, paper, or the like as a base material.
[0002]
[Prior art]
2. Description of the Related Art In recent years, signal delay has become a problem as electronic devices have become higher in density, higher in signal speed, and higher in frequency. Since the signal delay time increases in proportion to the square root of the dielectric constant, a laminate having a low dielectric constant is required for a laminate used for a printed wiring board of high-speed electronic equipment. In addition, heat resistance, moisture resistance, mechanical strength, flame retardancy, moldability, and the like are required, and various resin compositions for laminates have been proposed to improve these characteristics.
[0003]
For example, JP-A-1-163256 discloses a phenol obtained by adding a phenol to a butadiene (co) polymer having a number average molecular weight of 500 to 5,000 and at least 50% of the bound butadiene unit having 1,2 bonds. There has been proposed a flame retardant laminate fat composition comprising an addition butadiene (co) polymer, a brominated bisphenol A type epoxy resin and / or a brominated novolak type epoxy resin, and a curing accelerator.
[0004]
The phenol-added butadiene (co) polymer is suitable for a resin composition for a laminate from the viewpoint of lowering the dielectric constant, and has recently attracted attention. As a production method thereof, for example, in WO 91/09062, a butadiene polymer having a number average molecular weight of 300 to 3000 is divided and added to a system containing phenols and boron trifluoride and / or a boron trifluoride complex. A method for producing a phenol-added butadiene polymer having a number average molecular weight of 500 to 5,000 by reacting at 50 to 120 ° C. and a water content of 100 ppm by weight or less in a reaction system is disclosed. This method results in the addition (alkylation) of phenols to the butadiene polymer and the intramolecular cyclization of the butadiene polymer.
[0005]
However, in the conventional production method, a gel-like substance is generated during the reaction depending on the production conditions, and the filtration operation after the reaction takes a long time, so that the production efficiency may be significantly deteriorated, and improvement is required. .
[0006]
[Problems to be solved by the invention]
An object of the present invention is to be suitable for a resin composition for a laminate having excellent electrical properties such as a dielectric constant and a dielectric loss tangent, a high glass transition temperature, and excellent properties such as heat resistance, moisture resistance and flame retardancy. It is an object of the present invention to provide an efficient method for producing a phenol resin having a reduced amount of gelled product.
[0007]
[Means for Solving the Problems]
The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found a method capable of efficiently producing a phenol-added butadiene (co) polymer with less generation of a gel-like substance. .
[0008]
That is, the first aspect of the present invention is that, when a phenol is reacted with a butadiene (co) polymer in the presence of an acid catalyst to produce a phenol resin, the phenol and the butadiene (co) polymer are compatible. The present invention relates to a method for producing a phenol resin, which comprises contacting and reacting in a uniform state.
A second aspect of the present invention relates to the method for producing a phenolic resin according to the first aspect of the present invention, wherein a temperature at which a phenol and a butadiene (co) polymer are contacted and reacted is 85 to 120 ° C. Things.
A third aspect of the present invention is a method for producing a phenolic resin according to the first or second aspect of the present invention, wherein a phenol and a butadiene (co) polymer are contacted and reacted in the presence of a compatibilizer. It is about.
A fourth aspect of the present invention is that the butadiene (co) polymer has a number average molecular weight of 500 to 5,000, and 85% or less of the bound butadiene unit has 1,2 bonds. 3. A method for producing a phenolic resin according to any one of (3) to (3).
[0009]
Hereinafter, the present invention will be described in detail.
The phenol used in the present invention refers to at least one compound selected from a monohydric phenol, a polyhydric phenol, and an alkyl-substituted product thereof. The alkyl-substituted product is obtained by substituting 1 to 3 alkyl groups having 1 to 12 carbon atoms. Specifically, monohydric phenols such as phenol, o-cresol, m-cresol, p-cresol, ethylphenol, propylphenol, butylphenol, tert-butylphenol, amylphenol, hexylphenol, octylphenol, nonylphenol, dodecylphenol and xylenol And polyhydric phenols such as hydroquinone, resorcin, catechol and bisphenol, and mixtures thereof. Particularly, phenol, cresol and xylenol are preferably used.
[0010]
The butadiene (co) polymer used in the present invention can be produced by a conventionally known method as disclosed in JP-A-3-55238. For example, a polycyclic aromatic compound such as naphthalene is activated by using an alkali metal such as sodium or an organometallic compound thereof as a catalyst in a hydrocarbon solvent or an alkali metal such as sodium in a polar solvent such as tetrahydrofuran as a catalyst. As an agent, it can be obtained by homopolymerization of butadiene or copolymerization of butadiene with 50 mol% or less of another vinyl monomer such as styrene or isoprene. The butadiene (co) polymer used in the present invention has a number average molecular weight of 500 to 5,000, preferably 600 to 3,000, and has 1,2 bonds of 85 from the viewpoint of strength after curing, heat resistance, moldability, and the like. %, Preferably 50 to 80%.
[0011]
Examples of the acid catalyst used in the present invention include inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid, and organic acids such as formic acid, acetic acid, and oxalic acid, boron trifluoride, boron trifluoride-ether complex, and boron trifluoride-phenol complex. For example, a Friedel-Crafts catalyst such as boron trifluoride / water complex, boron trifluoride / alcohol complex, boron trifluoride / amine complex, or a mixture thereof is used. Among these, boron trifluoride, boron trifluoride / phenol complex, and boron trifluoride / ether complex are preferably used from the viewpoint of catalytic activity and ease of catalyst removal.
[0012]
In the present invention, the phenol is reacted with a butadiene (co) polymer in the presence of the acid catalyst to produce a phenol resin.
The reaction method is not particularly limited, but it is preferable that a predetermined phenol and an acid catalyst are charged into a reactor, and then a butadiene (co) polymer is dropped.
[0013]
The molar ratio of the butadiene (co) polymer to the phenol used is appropriately adjusted depending on the molecular weight and melt viscosity of the desired phenol resin. Usually, the phenols / butadiene (co) polymer is adjusted in the range of 1 to 20 (molar ratio), and from the viewpoint of controlling the molecular weight distribution, 2 to 15 (molar ratio) is preferable, and 3 to 10 is more preferable. (Molar ratio). The molar ratio can be appropriately adjusted within the above range according to the reaction conditions such as the amount of the catalyst used, the reaction temperature, and the time.
The number of moles of the butadiene (co) polymer is a value obtained by converting butadiene (molecular weight: 54) into one unit. For example, a butadiene (co) polymer having a number average molecular weight of 540 is converted to 10 moles. .
[0014]
The concentration of the catalyst is preferably 0.01 to 1% by mass, more preferably 0.03 to 0.5% by mass, based on the total amount of the phenol, butadiene (co) polymer and acid catalyst. For example, when reacting phenol with a butadiene (co) polymer in the presence of a boron trifluoride / phenol complex, the total amount of phenol, butadiene (co) polymer and boron trifluoride / phenol complex is Thus, boron trifluoride is adjusted to fall within the above range. If the catalyst concentration is more than 1% by mass, the progress of the reaction will be too fast to control the phenol addition amount, and if it is less than 0.01% by mass, the progress of the reaction will be extremely slow and the production efficiency will be remarkably low. It is not preferable because it deteriorates.
Note that the catalyst concentration needs to be maintained over the entire process of the reaction. Therefore, when a phenol and an acid catalyst are first charged into a reactor and a butadiene (co) polymer is dropped and reacted, the catalyst concentration at the start of the reaction is actually the concentration of phenol, but from the start of the reaction The above-mentioned range of the catalyst concentration is maintained until the end.
[0015]
In the above-mentioned catalyst concentration region, water affects the catalytic activity and the resin composition, and when the amount of water is large, the catalytic activity is reduced and the progress of the reaction is slowed, so that the production efficiency is reduced and the control of the resin composition becomes difficult. . Therefore, the water concentration in the phenol and butadiene (co) polymer before the addition of the catalyst before the start of the reaction is preferably 500 ppm or less. In particular, phenols are preferably subjected to an appropriate dehydration operation by a method of azeotropic distillation with an organic solvent as necessary under a nitrogen stream.
[0016]
The amount of the acid catalyst used and the amount of water in the raw material are not limited to the above ranges, and it is preferable to appropriately adjust the balance within a range where the resin composition can be controlled. Usually, it is preferable that the reaction is carried out in an atmosphere of an inert gas such as nitrogen to prevent water from entering the reaction system, and that the amount of water in the reaction system be 500 ppm or less.
[0017]
Next, the improvement of the contact / reaction conditions of phenols and butadiene (co) polymer, which is a feature of the present invention, will be described.
In general, the solubility of butadiene (co) polymer in phenols is not high, and when they are brought into contact under severe conditions in which acids coexist, the butadiene (co) polymers react with each other and become insoluble and insoluble. May be by-produced. The gel-like substance locally aggregates in the reactor to block the flow tube, or deteriorates the filtration efficiency in the filtration treatment after the reaction, which may cause a significant decrease in production efficiency. Therefore, it is not preferable.
[0018]
In the present invention, by-producing a gel-like substance can be suppressed by bringing the phenol and the butadiene (co) polymer into contact with each other so as to be compatible and uniform. The contact conditions are not particularly limited as long as they are compatible and uniform, but the temperature at the time of contact and the reaction temperature are controlled, the addition of a compatibilizing agent for improving the compatibility, or a combination of the both is used. Is preferably performed.
In the present invention, the term “compatible and uniform” refers to a state where there is no boundary (including an unclear one) between a phenol and a butadiene (co) polymer. This state is determined by the following method. The maximum amount of butadiene (co) polymer finally used in the actual reaction system is mixed with phenol (that is, the mixture of phenol and butadiene (co) polymer at a mass ratio of 60:40). It is prepared separately, the temperature is gradually increased, and the boundary between the two is visually observed. For example, when phenol and butadiene (co) polymer are mixed at a mass ratio of 60:40, a clear boundary is observed between the upper butadiene (co) polymer and the lower phenol below 80 ° C. When the temperature is raised, the boundary becomes unclear. At 85 ° C., the boundary completely disappears, and it can be confirmed that the whole is uniform. The embodiment is based on this determination method.
[0019]
It is important to control the contacting temperature and the reaction temperature in the range of 85 to 120 ° C, preferably 85 to 100 ° C. If the temperature is lower than 85 ° C., the compatibility of the butadiene (co) polymer with phenols is remarkably reduced. As a result, the reaction between the butadiene (co) polymers is promoted, and the formation of a gel-like substance is increased. If it exceeds, the reaction between double bonds and other side reactions in the butadiene (co) polymer similarly increase, which is not preferable.
[0020]
The compatibilizing agent is not particularly limited as long as it is compatible with both the phenols and the butadiene (co) polymer and can homogenize both, but it does not significantly affect the reaction and is inert. Desirably. From such a viewpoint, hydrocarbons having no polar group are preferably used, and specific examples thereof include cycloparaffins such as cyclopentane, cyclohexane, cyclopentane, cyclooctane, and alkylated products thereof. Particularly, cyclopentane and cyclohexane are preferable from the viewpoint of versatility. In addition, aromatic solvents such as benzene, toluene and xylene can be used in combination.
[0021]
As a method of adding the compatibilizer, a method such as adding the butadiene (co) polymer to the phenol in advance by adding it to the phenol or the butadiene (co) polymer or both in advance, and the like is used. Is mentioned.
[0022]
The amount of the compatibilizer is determined according to the solubility of the phenol and the butadiene (co) polymer, and is preferably 2% by mass based on the total amount of the phenol, the butadiene (co) polymer and the compatibilizer used. % Or more, preferably 5% by mass or more.
[0023]
The reaction time is appropriately adjusted depending on the set value of the amount of the phenol added to the butadiene (co) polymer, and is usually selected in the range of 10 minutes to 60 hours, preferably 1 to 20 hours, more preferably 1 to 20 hours. Performing the reaction in the range of 2 to 10 hours enables efficient control of the reaction.
[0024]
The amount of the phenol added is not particularly limited. However, from the viewpoint of the balance between the curing properties and the fluidity and the handleability during molding, the hydroxyl equivalent in the resin is from 100 g / eq to 1000 g / eq, particularly 200 g / eq. It is preferable to adjust so as to be within the range of 500 g / eq. The above hydroxyl equivalent is a value measured by an alkali reverse titration method of an acetylated product in a pyridine-acetic anhydride solution. The molecular weight (number average molecular weight in terms of polystyrene by gel permeation chromatography) of the phenolic resin is preferably from 500 to 5,000, more preferably from 1,000 to 4,000. If it is less than this range, the heat resistance and curability are not sufficient, and if it exceeds this range, the viscosity is too high and the moldability is lowered, so neither is preferred. The softening point of the phenol resin is preferably from 130C to 200C, more preferably from 100C to 180C. If it is less than this range, heat resistance and curability are not sufficient, and if it exceeds this range, moldability is deteriorated, and neither is preferred. The preferred number of double bonds per molecule of the phenol resin (by ¹³ C-NMR method) is 0 to 50 mol%, more preferably 0 to 30 mol%. Exceeding this range is not preferable because sufficient curing characteristics cannot be obtained.
[0025]
The content of the gel-like substance in the reaction mixture after completion of the reaction is desirably low within a range that does not affect the filtration rate in the filtration step described below, but is preferably 1 vol% or less, particularly 0.1 vol% with respect to the reaction solution. It is preferably at most 5 vol%, and according to the present invention, it can be controlled to such a range.
[0026]
The reaction is terminated by deactivating the catalyst when the amount of phenol added reaches a desired value. At that time, it is important to stop the reaction reliably. The means of deactivation is not particularly limited, but a method is used in which the deactivation treatment is quick and simple, and the residual amount of ionic impurities such as boron and fluorine in the finally obtained phenol resin is 100 ppm or less. Is preferred. From such a viewpoint, it is preferable to use hydrotalcites as the deactivator.
[0027]
After the quenching treatment, filtration is performed to remove the quenching agent and the like from the reaction mixture. The filtration method is not particularly limited, and can be performed by a conventionally known method. According to the production method of the present invention, since there are few gel-like substances, the filtration efficiency is remarkably improved. The workability can be further improved by adding a solvent, increasing the temperature of the filtrate, or increasing or decreasing the pressure in the system.
After filtration, unreacted phenols and the like are removed and concentrated by distillation to obtain a phenol resin. The distillation can be performed by a conventionally known method.
[0028]
In the present invention, by controlling the bonding mode of the butadiene (co) polymer, the reaction molar ratio of the phenols and the butadiene (co) polymer, the amount of the catalyst used, and the contact / reaction conditions in a well-balanced manner as described above, This makes it possible to produce a phenolic resin having little production of by-products and excellent in production efficiency, and having desired physical properties (hydroxyl equivalent, molecular weight distribution, etc.).
The laminate made from the phenolic resin obtained by the above production method has excellent electrical properties, especially dielectric properties, high glass transition temperature, and excellent moisture absorption, chemical resistance, and heat resistance. is there.
[0029]
【Example】
<Example 1>
2700 g of phenol and 10 g of boron trifluoride / phenol complex were charged into a 10 L reactor equipped with a reflux condenser and a stirrer, and 1000 g of Nisseki polybutadiene B-1000 (number average molecular weight: 1000, 1,2 bond: 63%) was added. It was added dropwise at 85 ° C. over 3 hours. At this time, polybutadiene and phenol were compatible and uniform. After completion of the dropwise addition, the mixture was stirred for another 2 hours without changing the temperature to continue the reaction. Then, 50 g of hydrotalcite (KW-1000, manufactured by Kyowa Chemical Co., Ltd.) was added, and the mixture was stirred at 90 ° C. for 30 minutes to lose the catalyst. I was alive.
The whole amount of the obtained reaction mixture was filled in a pressure filter having a capacity of 5 L, and filtration was performed under a pressure of 0.1 MPa. Filtration of the entire amount was completed in 510 seconds without clogging.
When 100 ml of the filtrate was collected and centrifuged, the amount of gel-like substances aggregated at the lower part of the separation tube was 0.1 ml or less.
The obtained filtrate was concentrated under reduced pressure by distillation to remove unreacted phenol to obtain phenol-added polybutadiene. The OH equivalent of this resin was 415 g / eq, the molecular weight was 3,500, the number of double bonds was 8 mol%, and the softening point was 152 ° C.
[0030]
<Example 2>
2700 g of phenol and 10 g of a boron trifluoride-phenol complex were charged into a 10 L reactor equipped with a reflux condenser and a stirrer, and 1000 g of Nisseki polybutadiene B-1000 (number average molecular weight: 1,000, 1,2 bond: 63%) was obtained. A mixture obtained by adding 200 g of cyclohexane and sufficiently stirring and mixing was dropped at 80 ° C. over 3 hours. At this time, polybutadiene and phenol were compatible and uniform. After completion of the dropwise addition, the mixture was stirred for 2 hours without changing the temperature to continue the reaction, and then 50 g of hydrotalcite (KW-1000, manufactured by Kyowa Chemical Co., Ltd.) was added. The mixture was stirred at 90 ° C. for 30 minutes to deactivate the catalyst. I let it.
The whole amount of the obtained reaction mixture was filled in a pressure filter having a capacity of 5 L, and filtration was performed under a pressure of 0.1 MPa. Filtration of the entire amount was completed in 480 seconds without clogging.
When 100 ml of the filtrate was collected and centrifuged, the amount of gel-like substances aggregated at the lower part of the separation tube was 0.1 ml or less.
The obtained filtrate was concentrated under reduced pressure by distillation to remove unreacted phenol to obtain phenol-added polybutadiene. The OH equivalent of this resin was 420 g / eq, the molecular weight was 3,400, the number of double bonds was 8 mol%, and the softening point was 150 ° C.
[0031]
<Comparative Example 1>
The procedure was performed in the same manner as in Example 1 except that the temperature for dropping polybutadiene and changing the reaction temperature was changed to 80 ° C. In addition, at the time of dropping and reaction, polybutadiene and phenol were not partially compatible and were not uniform.
When the obtained reaction mixture was filtered under a pressure of 0.1 MPa, the filtration rate was remarkably reduced when about 500 g was filtered, and it took 1830 seconds until finally complete filtration was completed.
When 100 ml of this filtrate was collected and centrifuged, the amount of gel-like substances aggregated at the lower part of the separation tube was 2.2 ml.
The obtained filtrate was concentrated under reduced pressure by distillation to remove unreacted phenol to obtain phenol-added polybutadiene. The OH equivalent of this resin was 415 g / eq, the molecular weight was 3,500, the number of double bonds was 7 mol%, and the softening point was 153 ° C.
[0032]
【The invention's effect】
According to the production method of the present invention, by-products of the gel-like material are suppressed, the electric properties such as the dielectric constant and the dielectric loss tangent are excellent, the glass transition temperature is high, and the heat resistance, moisture resistance, flame retardancy, etc. A phenol resin suitable for a resin composition for a laminate having excellent properties can be efficiently produced.

Claims (4)

In the case of producing a phenolic resin by reacting a phenol with a butadiene (co) polymer in the presence of an acid catalyst, the phenol and the butadiene (co) polymer are made compatible, contacted and reacted in a uniform state. A method for producing a phenolic resin. The method for producing a phenolic resin according to claim 1, wherein the temperature at which the phenol and the butadiene (co) polymer are contacted and reacted is 85 to 120C. 3. The method for producing a phenolic resin according to claim 1, wherein the phenol and the butadiene (co) polymer are contacted and reacted in the presence of a compatibilizer. The phenolic resin according to any one of claims 1 to 3, wherein the butadiene (co) polymer has a number average molecular weight of 500 to 5000, and 85% or less of the bound butadiene unit has 1,2 bonds. Production method.