JPS6360787B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a phenolic resin composition that is used to produce a cured product that has excellent electrical properties and extremely good punching workability, particularly a laminate suitable for arranging and holding electrical components. In recent years, due to technological innovations in communication devices and electronic devices, there has been a demand for more sophisticated electrical and physical properties of laminates. Further, from the viewpoint of automation of processing equipment, labor saving, etc., laminates are required to have excellent punching characteristics at room temperature or relatively low temperatures around room temperature. In response to these demands, methods have been tried in the past, such as adding thermoplastic polymers and plasticizers to phenolic resins, using phenol derivatives with long-chain hydrocarbon substituents as raw materials, and incorporating rubber into them. Ta. However, these methods do not provide satisfactory results because sufficient flexibility cannot be obtained, electrical and physical properties are deteriorated, and workability is deteriorated. A method has also been proposed in which phenols are reacted with drying oil or liquid polybutadiene in the presence of an acid catalyst and then reacted with formaldehyde to produce a flexible phenolic resin for laminated boards.
However, the addition of phenols to drying oils or liquid diolefin polymers having non-conjugated double bonds is relatively slow, and side reactions such as cyclization and polymerization of the double bond portion also occur. Therefore, when trying to add a large amount of phenol, these side reactions also occur actively, resulting in a high molecular weight that becomes difficult to dissolve in polar solvents when made into varnish, poor compatibility with phenolic resin, and paper or cloth. Penetration is poor and sluggish. Due to these drawbacks, it is difficult to obtain a laminate with good properties. Phenol resins modified with drying oils containing conjugated double bonds, such as tung oil, have relatively few of the above-mentioned drawbacks and can provide excellent flexibility, but because they are natural oils, price fluctuations are large, and electronic technology New flexibility-imparting agents are desired, for reasons such as the fact that we are no longer able to cope with the increasing level of physical and electrical properties required by the development of plastics. The present invention provides (A), (a) a maleic anhydride adduct of a drying oil having a conjugated and/or non-conjugated double bond with the general formula (In the formula, R ₁ and R ₂ represent organic residues having 1 to 20 carbon atoms that are the same or different from each other.) A drying oil having a secondary amine group obtained by imidizing a diamine compound represented by the following formula: and (b)
General formula for maleic anhydride adducts of butadiene polymers and/or copolymers with a number average molecular weight of 300 to 10,000. (In the formula, R ₁ and R ₂ are the same or different organic residues having 1 to 20 carbon atoms) A butadiene polymer and/or a secondary amine-containing diamine compound obtained by imidization reaction Or, an essential component is a resol type phenolic resin obtained by reacting one or two selected from copolymers (a) and (b) with (B) phenols and formaldehyde in the presence of an alkali catalyst. The present invention relates to a curable phenolic resin composition containing: The drying oil containing a secondary amine, which is one component of the phenolic resin composition of the present invention, will be explained. Examples of drying oils having conjugated and/or non-conjugated double bonds include linseed oil, edible oil, soybean oil, tung oil, dehydrated castor oil, etc. whose main components are linolenic acid, linoleic acid, and eleostearic acid. . The maleic anhydride adduct of drying oil in the present invention can be produced by a conventionally known method of reacting the drying oil and maleic anhydride at a temperature of 50 to 300°C. In the case of a drying oil having a conjugated double bond, maleic anhydride is added by the Diels-Alder mechanism, so the maleation reaction can be carried out at a relatively low temperature of 50 to 150°C. On the other hand, in the case of drying oils having non-conjugated double bonds, it is better to carry out the treatment at a somewhat higher temperature, such as 150 to 300°C. The reaction temperature can also be lowered somewhat by adding a small amount of organic peroxide or by using an aerated drying oil. A gelation inhibitor is usually not required during the maleic anhydride addition reaction, but depending on the reaction conditions, a small amount of phenylene diamic acid, pyrogallols, naphthols, etc. may be added to prevent the gelation reaction. The amount of maleic anhydride added is preferably 0.05 to 1.0 mol, preferably 0.1 to 0.5 mol, per 100 g of drying oil. In the present invention, not only drying oils having conjugated double bonds but also drying oils having non-conjugated double bonds, which have conventionally been difficult to put into practical use for general purposes, can be used. This is because the maleation reaction of drying oils having non-conjugated double bonds is easy, and addition of maleic anhydride is possible with relatively few side reactions such as increase in molecular weight. Maleic anhydride adducts of drying oils have the following general formula: (In the formula, R ₁ and R ₂ represent the same or different organic residues having 1 to 20 carbon atoms). This reaction method can be carried out, for example, according to the method described in JP-A-53-63439. This reaction is an imidization reaction between a succinic anhydride group or its half-esterified product and a primary amine. The diamine compound used is preferably used in an equivalent amount to the succinic anhydride group, but it is also possible to use an excess of the diamine compound and distill off the end-reacted diamine compound after the reaction is completed. The diamine mentioned here is typically one in which R ₁ and R ₂ are hydrocarbon residues, but diamines in which some of the hydrogens of the hydrocarbon residues are substituted with hydroxyl groups can also be effectively used. can. A typical example of this diamine is H ₂ N(CH ₂ ) _o NH
(CH ₂ ) _n H (m, n is 1 to 12), H ₂ N (CH ₂ ) _o NH
(CH ₂ ) _n OH (m and n are 1 to 12), such as methylaminoethylamine, ethylaminoethylamine, methylaminopropylamine, ethylaminopropylamine, butylaminopropylamine, β-hydroxyethylaminoethylamine,
An example is β-hydroxyethylaminopropylamine. In this reaction, in order to prevent a gelation reaction due to the reaction of the diamine compound, it is recommended to half-esterify the succinic anhydride group by adding an alcohol before adding the diamine compound. The imidization reaction is usually carried out at 50 to 300℃, preferably at 100℃.
Performed at temperatures of ~200°C. The imidization reaction can be carried out in the presence or absence of a solvent. When using a solvent, use hydrocarbon solvents such as benzene, toluene, xylene, cyclohexane, butyl cellosolve, ethyl cellosolve, n
Although alcoholic solvents such as butanol and ethereal solvents such as diglyme can be used, it is particularly preferable to carry out the half-esterification reaction using an alcoholic solvent prior to the imidization reaction. By the above imidization reaction, a secondary amine group is usually added to the drying oil in the following structure. (In the formula, R ₃ is a drying oil residue having a conjugated and/or non-conjugated double bond, R ₁ and R ₂ are organic residues having 1 to 20 carbon atoms that are the same or different from each other) A butadiene polymer containing a secondary amine will be explained. The butadiene polymer containing a secondary amine of the present invention is a maleic anhydride obtained by reacting a butadiene homopolymer with a number average molecular weight of 300 to 10,000 or a butadiene copolymer with a butadiene unit content of 50% or more with maleic anhydride. General formula for butadiene polymer It can be synthesized by reacting with a diamine compound represented by the formula (wherein R ₁ and R ₂ represent the same or different organic residues having 1 to 20 carbon atoms). First, the raw material butadiene polymer used in the present invention is, for example, one obtained by homopolymerizing butadiene in a hydrocarbon solvent using an alkali metal such as lithium or sodium or an organometallic compound thereof as a catalyst, or one obtained by homopolymerizing butadiene and a vinyl monomer such as styrene. Copolymerization of butadiene and diolefin such as isoprene are preferably used. Also preferably used are butadiene monopolymerized or copolymerized with an alkali metal such as sodium as a catalyst in a polar solvent such as tetrahydrofuran using a polycyclic aromatic compound such as naphthalene or anthracene as an activator. Furthermore, butadiene polymers or copolymers obtained by using a coordination anion polymerization catalyst, and polymers obtained by telomerizing butadiene etc. with a radical initiator can also be used in the same way. . The number average molecular weight of the butadiene polymer referred to in the present invention is in the range of 300 to 10,000, preferably 500 to 5,000.
If the molecular weight is too low, the molecular weight between the crosslinking points will be too small, which will not only result in poor flexibility, but also result in poor performance such as strength, heat resistance, and chemical resistance of the cured product. If the molecular weight is too large, the viscosity becomes extremely high, resulting in decreased workability and difficulty in obtaining a uniform cured product. The microstructure of the butadiene polymer used in the present invention is not particularly limited, and either a polymer with many 1,2-bonds or a polymer with many 1,4-bonds can be used. The maleic anhydride adduct of the butadiene polymer or copolymer or mixture thereof of the present invention is produced by a conventionally known method of reacting the above-described butadiene polymer or copolymer with maleic anhydride at a temperature of 100 to 300°C. can. Moreover, a method of suppressing the gelation reaction by adding a small amount of a gelling inhibitor such as phenylene diamines, pyrogallols, or naphthols when carrying out the addition reaction can be preferably employed. In addition, the adduct of maleic anhydride in this reaction is 0.05 to 1.0 mol per 100 g of butadiene polymer or copolymer.
Preferably it is 0.1 to 0.5 mol. The maleic anhydride adduct of butadiene polymer has the following general formula: React with the diamine compound shown in This diamine is the same as the diamine used in the reaction with the maleic anhydride of the drying oil described above. Regarding this reaction method, for example, JP-A-Sho
It can be carried out according to the method described in No. 53-63439. This reaction is an imidization reaction between a succinic anhydride group or its half-esterified product and a primary amine. The diamine compound used is preferably used in an amount equivalent to the succinic anhydride group, but it is also possible to distill off unreacted diamine compounds after the reaction using an excess of the diamine compound. In this reaction, in order to prevent a gelation reaction due to the reaction of the diamine compound, it is recommended to half-esterify the succinic anhydride group by adding an alcohol before adding the diamine compound. The imidization reaction is usually carried out at 50 to 300℃, preferably at 100℃.
Performed at temperatures of ~200°C. The imide compound can be formed in the presence or absence of a solvent. When using a solvent, hydrocarbon solvents such as benzene toluene, xylene, cyclohexane, butyl cellosolve, ethyl cellosolve, n
- Alcohol solvents such as butanol and ether solvents such as diglyme can be used, but
Particularly preferred is a method in which a half-esterification reaction is performed using an alcohol solvent prior to an imidization reaction. Through the above imidization reaction, a secondary amine group is usually added to the butadiene polymer in the following structure. (In the formula, R ₄ is a butadiene polymer and/or copolymer with a number average molecular weight of 300 to 10,000, R ₁ and R ₂ are the same or different, and have 1 to 20 carbon atoms.
carbon residues). The same raw materials and reaction conditions can be used in the synthesis of the above-mentioned drying oil having a secondary amine group and the above-mentioned butadiene polymer and/or copolymer. When it is intended to use a mixture of both oil and (b) a butadiene polymer having secondary amine groups, the drying oil as a raw material and the butadiene polymer and/or copolymer are mixed and then maleic anhydride is added. It is also possible to react and further react with diamines having secondary amines. The other component of the thermosetting resin composition of the present invention, the phenol-formaldehyde resin, is
It is obtained by condensing phenols and aldehydes with a basic catalyst. As the phenols, in addition to phenol, cresol, xylenol, resorcinol, bisphenol, etc. are used alone or in combination. As aldehydes, in addition to formaldehyde, it is also possible to use paraformaldehyde, which decomposes to generate formaldehyde. As the basic catalyst used for phenolic resin condensation, hydroxides of alkali metals or alkaline earth metals, ammonia, amines, etc. are preferably used. Drying oil with secondary amine and/or butadiene polymer with secondary amine and phenol
Formaldehyde resins can be used by mixing those synthesized separately, or by condensing phenols and formaldehyde in the presence of a drying oil having a secondary amine and/or a butadiene polymer having a secondary amine. It is also possible. The mixing ratio of the drying oil with secondary amines and/or the butadiene polymer with secondary amines and the phenol-formaldehyde resin can be varied over a wide range, and depending on the mixing ratio, curing with different properties can be achieved. You can get things. When a drying oil having a secondary amine or a butadiene polymer having a secondary amine is blended alone with a phenol-formaldehyde resin, a drying oil having a secondary amine or a butadiene polymer having a secondary amine and a phenol- The amount of formaldehyde resin is 5:95 to 80:20 by weight,
Further, a range of 20:80 to 60:40 is preferably adopted in order to obtain a cured product having desirable characteristics. In addition, when a drying oil having a secondary amine and a butadiene polymer having a secondary amine are used at the same time, the weight ratio of the total amount of both to the amount of phenol-formaldehyde resin is 5:95 to 80:20, and A range of 20:80 to 60:40 is preferably adopted in order to obtain a cured product having desirable properties.
Here, the ratio of the drying oil having a secondary amine to the butadiene polymer having a secondary amine may be, for example, 5:95 to 95:5. The thermosetting resin composition of the present application can be cured at a temperature of 100 to 250°C without particularly adding a catalyst. In order to obtain a laminate plate suitable for arranging and holding electrical components, such as a wiring printed board or a chassis board, using this thermosetting resin, it is preferable to carry out the following procedure, for example. That is, the drying oil having a secondary amine and/or the butadiene polymer having a secondary amine, and the phenol-formaldehyde resin contained in the thermosetting resin composition are mixed with alcohols such as methanol, ethanol, butanol, acetone, and methyl ethyl ketone. A varnish is prepared by dissolving it in one or more solvents such as ketones such as, aromatic hydrocarbons such as benzene, toluene, and xylene. Next, the above-mentioned varnish is impregnated into a fibrous base material for a laminate and dried to obtain a laminate material having a dry resin content of 30 to 70% by weight, preferably 35 to 55% by weight. Paper, cloth, synthetic fiber cloth, asbestos cloth, glass cloth, etc. are used as the fibrous base material. The drying oil having a secondary amine and the butadiene polymer having a secondary amine of the present invention have excellent solubility in methanol-based solvents and acetone-based solvents, and provide a varnish with low viscosity, so that they can penetrate into fibrous base materials. It also has excellent sex. Laminate the desired number of layers of this laminated material, usually 20 to 200.
Kg/cm ² , temperature 130 to 180°C, and time 20 to 180 minutes to mold by thermocompression to obtain a final product, a laminate. Furthermore, the phenolic resin composition of the present invention naturally exhibits excellent flexibility when cured, but the drying oil having a secondary amine group and the butadiene polymer having a secondary amine group are Because the curing reaction with the phenolic resin is excellent and the curing reaction with the phenolic resin is fast, the crosslinking density is kept high, and a laminate with excellent boiling resistance, heat resistance, solvent resistance, and dimensional stability can be obtained. The resin composition of the present invention can be widely applied not only to laminate products but also to fields such as electrical insulation coatings. The present invention will be specifically explained below using Examples. Synthesis Example 1 Synthesis was carried out according to the order of the reaction formula shown below. 1000 g of linseed oil and 206 g (2.1 mol) of maleic anhydride were reacted at 195℃ for 3 hours to obtain an acid value of 98 mgKOH/
g of maleated linseed oil was obtained. (Reaction 1) Next, 1000 g of the above maleated linseed oil and 310 g (2.62 mol) of butyl cellosolve were placed in a three-separable flask equipped with a reflux condenser, heated to 125° C., and reacted for 4 hours. (Reaction 2) Then the reaction mixture was heated to 80%
℃, and add 182 g (1.75 mol) of β-hydroxyethylaminoethylamine from the dropping funnel to approx.
It was dripped over several minutes. The temperature of the reaction mixture was raised to 145°C over 1 hour, and the reaction was continued at the same temperature for 3 hours.
Water, butyl cellosolve, and unreacted amine were distilled from the reaction mixture under reduced pressure at the same temperature to obtain () in a nearly quantitative yield. 1150 g of a methanol-toluene mixture (1:1 weight ratio) was added to () to prepare a varnish with a resin concentration of 50% by weight. (Reaction 3) Synthesis example 2 (1) nC″ ₄ → (C″ ₄ ) _o (number average molecular weight 1200) (′) Number average molecular weight 1200, synthesized by polymerizing butadiene using a sodium-based catalyst.
1000 g of butadiene polymer with 58% vinyl bonds (0.83
mol) and 212 g (2.16 mol) of maleic anhydride were obtained.
mol) at 195℃ for 5 hours to obtain an acid value of 100mg.
A maleated butadiene polymer of KOH/g was obtained.
Next, 1000 g of the above maleated butadiene polymer and 316 g (2.68 mol) of butyl cellosolve were placed in a three-separable flask equipped with a reflux condenser, heated to 125° C., and reacted for 4 hours. Then the reaction mixture
Cool to 80℃ and add 185 g (1.79 mol) of β-hydroxyethylaminoethylamine from the dropping funnel.
It was added dropwise over 15 minutes. The temperature of the reaction mixture was raised to 145°C over about 1 hour, and the reaction was continued at the same temperature for 3 hours. The water, butyl cellosolve and unreacted amine produced in the reaction mixture are distilled off under reduced pressure at the same temperature to obtain a butadiene polymer having a secondary amine in almost quantitative yield. Next, 1153 g of a toluene-methanol mixture (1:1 weight ratio) was added to obtain a varnish with a resin concentration of 50% by weight. Synthesis Examples 3 to 5 Butadiene polymers having various secondary amines were synthesized according to Synthesis Examples 1 and 2. The butadiene polymer used in Synthesis Examples 3 and 4 was a vinyl-rich butadiene polymer synthesized using the same sodium as a catalyst as in Synthesis Example 2, and Synthesis Example 5 was a cis-1,4-type Sumica Oil #150 manufactured by Sumitomo Chemical Co., Ltd. belongs to. In all cases, butadiene polymers having secondary amines were obtained in almost quantitative yields. The results, including Synthesis Examples 1 and 2, are summarized in Table 1.

【table】

[Table] Synthesis Example 6 485 g of 37% formaldehyde aqueous solution, 470 g of phenol, and 34 g of 25% ammonia aqueous solution were heated at 90°C.
After the mixture was reacted for 30 minutes and dehydrated under reduced pressure, a mixed solution of toluene and methanol (1:1 weight ratio) was added to obtain a varnish with a resin concentration of 50% by weight. Synthesis Example 7 500 g of the butadiene polymer having secondary amine groups synthesized in Synthesis Example 2, 437 g (5.39 mol) of 37% formaldehyde aqueous solution, and 339 g of phenol.
(3.6 mol) was placed in a separable flask equipped with a reflux condenser, and 15.3 g (0.23 mol) of 25% aqueous ammonia was added dropwise from the dropping funnel over about 5 minutes, and the temperature was raised to 90°C over about 20 minutes. After reacting for 2.5 hours, the mixture was dehydrated under reduced pressure. The water distilled out at this time was 365g.
It was hot. Next, 926 g of toluene-methanol mixture (1:1 weight ratio) was added to make the resin concentration 50% by weight.
It was made into a varnish. Examples 1 to 7 The varnishes thus obtained were blended in the proportions shown in Table 2 below, and kraft paper was impregnated with the resulting mixed varnish. All varnishes had excellent permeability into paper. After drying, a resin-impregnated paper with a resin content of 50% by weight was obtained. Nine sheets of this resin-impregnated paper were stacked together and heated and pressed for 45 minutes at 150° C. and 100 kg/cm ² to obtain a laminate with a thickness of 1.6 mm. Various properties of this laminate are shown in Table 2 below. Comparative example 1 Tung oil 500g, metacresol 756g (7.0 mol),
2 g (0.01 mol) of para-toluenesulfonic acid was mixed and reacted at 100°C for 2 hours. Next, 738g (9.1 mol) of 37% formalin and 48g of 25% aqueous ammonia.
(0.7 mol) was added and reacted at 90°C for 3 hours. Water was removed under reduced pressure, and a methanol-toluene (1:1 weight ratio) mixed solution was added to give a varnish with a resin concentration of 50% by weight. Kraft paper was impregnated with the varnish thus obtained and dried to obtain resin-impregnated paper with a resin content of 50% by weight. This was made into a laminate under exactly the same conditions as Examples 1 to 4. The properties of the laminate are shown in Table 2 below.
Shown below. Comparative example 2 500 g of linseed oil, 756 g (7.0 mol) of metacresol, 3 g (0.15 mol) of para-toluenesulfonic acid
were mixed and reacted at 120°C for 2 hours. followed by 37%
Formalin 738g (9.1mol), 25% ammonia water
48g (0.7mol) was added and reacted at 90°C for 3 hours. Water was removed under reduced pressure, and a methanol-toluene (1:1 weight ratio) mixed solution was added to give a varnish with a resin concentration of 50% by weight. The varnish thus obtained is impregnated on kraft paper, dried and has a resin content of 50
Resin-impregnated paper adjusted to % by weight was obtained. This was made into a laminate under exactly the same conditions as Examples 1 to 4. Various properties of the laminate are shown in Table 2 below. As is clear from the results shown in Table 2 below, compared to conventional phenolic resins modified with tung oil and linseed oil, drying oils with secondary amines, butadiene polymers with secondary amines, and mixtures of both are resol type. It is clear that when blended with phenolic resin, solvent resistance, heat resistance, and punching workability are improved without deteriorating electrical properties.

【table】

Claims (1)

[Claims] 1 (A) (a) A maleic anhydride adduct of a drying oil having a conjugated and/or non-conjugated double bond with the general formula (R ₁ and R ₂ are the same or different organic residues having 1 to 20 carbon atoms) A drying oil having a secondary amine group obtained by imidizing a diamine compound represented by: and (b) number average molecular weight The general formula for maleic anhydride adducts of butadiene polymers and/or copolymers with 300 to 10,000 (R ₁ and R ₂ are the same or different organic residues having 1 to 20 carbon atoms) A butadiene polymer and/or copolymer having a secondary amine group obtained by imidizing a diamine compound represented by 1 or 2 selected from (a) and (b) of
(B) A curable phenolic resin composition containing as an essential component a resol type phenolic resin obtained by reacting phenols and formaldehyde in the presence of an alkali catalyst.