JPS6248699B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a phenolic resin composition which is used to produce a cured product having excellent electrical properties and extremely good punching workability, particularly a laminate suitable for arranging and holding electrical parts. It is about things. In recent years, technological innovations in communication devices and electronic equipment have created 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 sufficient flexibility, deteriorate electrical or physical properties, or
The work efficiency is deteriorated and a fully satisfactory result is not obtained. 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. Drying oils with conjugated double bonds, such as phenolic resins modified with 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 the development of electronic technology New flexibility-imparting agents are desired because we have reached the stage where we can no longer meet the increasing levels of physical and electrical properties required by the industry. The present invention relates to (A) a drying oil containing an amide group obtained by reacting a maleic anhydride adduct of a drying oil having conjugated and/or non-conjugated double bonds with ammonia and/or a primary amine; A derivative of a butadiene polymer containing an amide group obtained by reacting a maleic anhydride adduct of a butadiene polymer with an average molecular weight of 300 to 10,000 with ammonia and/or a primary amine, and (C) a phenol and The present invention relates to a curable phenolic resin composition containing as an essential component a resol type phenolic resin obtained by reacting formaldehyde in the presence of an alkali catalyst. By using the phenolic resin composition of the present invention, drying oils having non-conjugated double bonds, which have hitherto been difficult to put to practical use, can also be used. This is because the maleation reaction of drying oils with non-conjugated double bonds is easy, and addition of maleic anhydride is possible with relatively few side reactions such as polymerization, and the amidation reaction with ammonia etc. This is because it can be carried out under mild conditions and no undesirable side reactions occur. Furthermore, the phenolic resin composition of the present invention not only exhibits excellent flexibility when cured, but also maintains a high crosslinking density due to the rapid curing reaction between the drying oil containing an amide group and the phenolic resin. A laminate with excellent sagging, boiling resistance, heat resistance, solvent resistance, and dimensional stability can be obtained. Next, the drying oil containing an amide group, which is contained as one of the essential components of the phenolic resin composition used in the present invention, will be explained. Drying oils having conjugated and/or non-conjugated double bonds with an iodine value of 100 or more that can be employed in the present invention include linseed oil, edible oil, and linseed oil containing linolenic acid, linoleic acid, and eleostearic acid as main components; Examples include soybean oil, tung oil, dehydrated castor oil, and the like. Furthermore, liquid conjugated diolefin polymers or copolymers can also be used in combination with these drying oils. 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 drying oils having conjugated double bonds, maleic anhydride is added by the Diels-Alder mechanism, so it is possible to carry out the maleation reaction 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 small amounts of organic peroxides or by using aerated drying oils. A gelation inhibitor is usually not required during the maleic anhydride addition reaction, but depending on the reaction conditions, a small amount of phenonylene diamines, pyrogallols, naphthols, etc. may be added to prevent the gelation reaction. . The amount of maleic anhydride added is preferably 0.05 to 0.6 mol, preferably 0.1 to 0.5 mol, per 100 g of drying oil. The maleic anhydride adduct of the drying oil is then reacted with ammonia and/or a primary amine to obtain the reactive amide compound. Succinic anhydride groups attached to drying oils readily react with ammonia or primary amines under mild conditions to give monoamide compounds. When ammonia or primary amine is reacted in an amount equal to or more than the succinic anhydride group, the excess ammonia or amine forms a salt with the carboxyl group. At a slightly higher reaction temperature, the amide group generated from the succinic anhydride group undergoes cyclodehydration with the other carboxyl group to simultaneously form a corresponding imide ring. As described above, depending on the reaction conditions, the reaction product may become somewhat complex, but in the present invention, it does not matter if the reaction product contains the above-mentioned by-products as long as the reaction conditions described below are observed. . It is also possible to make a drying oil containing an amide group water-soluble by adjusting the amounts of ammonia and primary amine α. The ammonia used in the present invention may be blown into the maleic anhydride adduct of the drying oil in gaseous form or may be added as aqueous ammonia. The primary amine is a compound represented by the general formula R- _NH2 (where R represents an alkyl group, an aryl group, an alkanol group, or an aralkyl group having 1 to 20 carbon atoms). The amount of ammonia and primary amine used is based on the molar ratio to the succinic anhydride group.
0.2 to 3.0 is preferably applied. The amidation reaction can be carried out at 0 to 150°C. The reaction is usually very fast, and a reaction time of 1 to 2 hours is sufficient. If the reaction temperature becomes too high, an imide ring will be generated by the dehydration reaction, so
Too high a temperature is not desirable. This reaction can be carried out in the presence or absence of a solvent. When using a solvent, it is preferable to use a hydrocarbon solvent or an ether solvent that is not reactive with ammonia, amines, carboxylic acids, and the like. However, even with reactive compounds such as alcohols, it is also possible to ring-open some of the succinic anhydride groups with alcohol to synthesize and utilize a drying oil that has both amide and ester groups. It is. The amidated butadiene polymer used in 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. It can be synthesized by reacting ammonia or a primary amine with a butadiene polymer. 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. The amount of maleic anhydride added in this reaction is usually 0.05 to 0.6 mol, preferably 0.1 to 0.5 mol, per 100 g of the butadiene polymer or copolymer. The maleic anhydride adduct of the butadiene polymer is then reacted with ammonia and/or a primary amine to yield the corresponding amide compound. The succinic anhydride group in the butadiene polymer acid adduct reacts with ammonia or a primary amine to easily obtain a monoamide compound. Succinic anhydride groups react with equivalent amounts of ammonia or primary amines to form monoamide bonds and carboxyl groups. If excess ammonia or amine is present, a carboxylate salt may be produced in addition to the amide bond, and furthermore, at a somewhat higher reaction temperature, the amide group formed from the succinic anhydride group may be bonded to the other carboxylic acid. It is conceivable that a dehydration reaction occurs with the group, and a corresponding imide ring formation reaction also occurs. In the present invention, an amidated butadiene polymer is used, and a portion of the polymer may include a carboxylic acid salt,
Even if an imide ring is formed, an amidated product obtained under the reaction conditions detailed below can be used without any problem. This amidation reaction usually has a sufficiently fast reaction rate and can be carried out at room temperature to 120°C, preferably room temperature to 50°C. If the reaction temperature becomes too high, the dehydration reaction will proceed further and the amide bond will disappear, and there is a risk that it will be completely transferred to an imide ring, which is not very preferable. This reaction can be carried out in the presence or absence of a solvent. When using a solvent, it is preferable to use a hydrocarbon solvent or an ether solvent that is not reactive with ammonia, amines, carboxylic acids, and the like. Of course, even with reactive compounds such as alcohols, it is also possible to open a part of the succinic anhydride group with alcohol to synthesize and utilize a polymer having both amide and ester groups. be. The ammonia used in this reaction may be blown into the maleic anhydride adduct of the butadiene polymer or into its solution in gaseous form, or may be added as concentrated aqueous ammonia. Furthermore, the primary amine used in the same manner has the general formula R′-NH ₂ (R′: alkyl group having 1 to 20 carbon atoms, aryl group,
It is a compound represented by an alkanol or aralkyl group). The amount of ammonia and primary amine used is preferably 0.2 to 3.0 in molar ratio to the succinic anhydride group. Furthermore, it is possible to make the amidated butadiene polymer water-soluble by adjusting the amounts of ammonia and primary amine, and it is also possible to directly blend it with the water-soluble phenol resin. Similar reaction conditions can be used in the synthesis of the above-mentioned drying oil having an amide group and the above-mentioned butadiene polymer derivative, so the raw material drying oil and butadiene polymer are mixed, and then maleic anhydride is reacted, and then ammonia and/or primary amines can be reacted. The other component of the thermosetting resin composition of the present invention, the phenol-formaldehyde resin, 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. The drying oil containing an amide group, a butadiene polymer derivative, and the phenol-formaldehyde resin can be synthesized separately and used as a mixture, or the drying oil and/or butadiene polymer derivative containing an amide group can be used. It is also possible to condense phenols with formaldehyde in the presence of . drying oil containing amide groups,
The mixing ratio of the butadiene polymer derivative and the phenol-formaldehyde resin can be varied over a wide range, and depending on the mixing ratio, cured products with various properties can be obtained. The weight ratio of the total amount of butadiene polymer derivative/the amount of phenol-formaldehyde resin is 5/95 to 80/20, or even 20/80 to 60/
A range of 40 is preferably adopted in order to obtain a cured product having desirable properties. Here, the weight ratio of the drying oil containing an amide group to the butadiene polymer derivative can 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, a drying oil containing an amide group, a derivative of a butadiene polymer, and a phenol-formaldehyde resin, which are contained as essential components in the thermosetting resin composition, are mixed with alcohols such as methanol, ethanol, butanol, acetone, methyl ethyl ketone, etc. A varnish is prepared by dissolving it in one or more solvents such as ketones, benzene, toluene, xylene, and other aromatic hydrocarbons. 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. 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. The present invention will be specifically explained below using Examples. Synthesis example 1 1000g of linseed oil and 333g of maleic anhydride at 195℃
The mixture was reacted for 3 hours to obtain maleated linseed oil with an acid value of 143 mgKOH/g. 1000g of the above maleated linseed oil, 800g of toluene
g was placed in a 3-separable flask equipped with a reflux condenser, heated to 50℃, and mixed with 25% ammonia water while stirring.
130g was added dropwise over about 30 minutes. 50℃ after completion of dripping
After stirring for 1 hour, the temperature was raised to 80℃.
Volatile components were distilled off under reduced pressure. Next, 1088 g of methanol was added to obtain a methanol solution with a resin concentration of 50% by weight. Synthesis example 2 1000 g of tung oil and 337 g of maleic anhydride were mixed at 110℃.
After a period of reaction, maleated tung oil with an acid value of 144 mgKOH/g was obtained. 1000 g of the above maleated tung oil and 800 g of toluene were placed in a 3-separable flask equipped with a reflux condenser, heated to 50°C, and mixed with 25% ammonia water with stirring.
g was added dropwise over about 30 minutes. After completion of the dropwise addition, the temperature was kept at 50°C and stirring was continued for 1 hour, then the temperature was raised to 80°C, and volatile components were distilled off under reduced pressure. Next, 1088 g of methanol was added to obtain a methanol solution with a resin concentration of 50% by weight. Synthesis Example 3 1000 g of maleated linseed oil with an acid value of 143 mg KOH/g synthesized in Synthesis Example 1 and 619 g of toluene were placed in a 3-separable flask equipped with a reflux condenser and heated to 50°C.
While stirring, 238 g of aniline was added dropwise over about 30 minutes. After the dropwise addition was completed, stirring was continued for 1 hour while maintaining the temperature at 50°C. Next, 619 g of methanol was added to obtain a toluene-methanol (1:1 weight ratio) solution with a resin concentration of 50% by weight. Synthesis Example 4 A butadiene polymer with a number average molecular weight of 800 and a vinyl bond content of 56% synthesized by polymerizing butadiene using a sodium catalyst was reacted with maleic anhydride at 195°C for 5 hours to obtain an acid value of 160 mg.
A maleated butadiene polymer of KOH/g was obtained. 1000 g of the maleated butadiene polymer and 800 g of toluene were placed in a 3-separable flask equipped with a reflux condenser, heated to 50° C., and 146 g of 25% aqueous ammonia was added dropwise over about 30 minutes while stirring. After dropping, keep at 50℃ and continue stirring for 1 hour, then raise to 80℃
The temperature was raised to , and volatile components were distilled off under reduced pressure. Next, 1049 g of methanol was added to obtain a methanol solution with a resin concentration of 50% by weight. Synthesis Example 5 485 g of 37% formaldehyde aqueous solution, 470 g of phenol and 34 g of 25% ammonia aqueous solution were heated at 90°C.
After reacting for 30 minutes and dehydrating under reduced pressure, methanol was added to make a varnish with a resin concentration of 50% by weight. Examples 1 to 3 The varnishes thus obtained were blended in the proportions shown in Table 1, and the resulting mixed varnish was impregnated into cotton linter paper and dried to give a resin impregnated amount of 45% by weight. Impregnated paper was obtained. Nine sheets of this resin-impregnated paper were stacked and thermocompressed for 80 minutes at 160° C. and 100 kg/cm ² to obtain a laminate with a thickness of 1.6 mm. The properties of the obtained laminate are shown in Table 1. Comparative Example 1 500 g of tung oil, 756 g of metacresol, and 2 g of para-toluenesulfonic acid were mixed and reacted at 100° C. for 2 hours. Next, 738 g of 37% formalin and 48 g of 25% aqueous ammonia were added and reacted at 90°C for 3 hours.
Water was removed under reduced pressure and methanol-toluene (1
1 weight ratio) was added to prepare a varnish with a resin concentration of 50% by weight. Cotton linter paper was impregnated with the varnish thus obtained and dried to obtain resin-impregnated paper with a resin content of 45% by weight. Examples 1 to 3
A laminate was made under exactly the same conditions as . Table 1 shows the properties of the laminate. Comparative Example 2 500 g of linseed oil, 756 g of metacresol, and 3 g of para-toluenesulfonic acid were mixed and reacted at 120° C. for 2 hours. Next, 738 g of 37% formalin and 48 g of 25% aqueous ammonia were added and reacted at 90°C for 3 hours. Water was removed under reduced pressure, and a mixture of methanol and toluene (1:1 weight ratio) was added to obtain a varnish with a resin concentration of 50% by weight. Cotton linter paper was impregnated with the varnish thus obtained and dried to obtain resin-impregnated paper with a resin content of 45% by weight. This was made into a laminate under exactly the same conditions as Examples 1 to 3.
Table 1 shows the properties of the laminate. As is clear from the results shown in Table 1, the composition has a drying oil containing an amide group, a butadiene polymer derivative, and a resol-type phenolic resin as essential components, compared to conventional phenolic resins modified with tung oil and linseed oil. It is clear that the material has improved solvent resistance, heat resistance, and punchability without deteriorating the electrical properties. 【table】

Claims (1)

[Claims] 1 (A) A maleic anhydride adduct of a drying oil having an iodine value of 100 or more and having a conjugated and/or non-conjugated double bond, obtained by reacting with ammonia and/or a primary amine. (B) A drying oil containing amide groups obtained by reacting a maleic anhydride adduct of a butadiene polymer with a number average molecular weight of 300 to 10,000 with ammonia and/or a primary amine. A curable resin composition containing as essential components a derivative of a butadiene polymer, and (C) a resol type phenolic resin obtained by reacting phenols and formaldehyde in the presence of an alkali catalyst.