JP5104308B2 - Biphenylene cross-linked phenol novolac resin and its use - Google Patents

Description

  The present invention relates to a biphenylene-crosslinked phenol novolak resin obtained by reacting bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl with a phenol mixture containing at least one dihydric phenol. In addition to being used as a curing agent for epoxy resins, the phenol novolac resin of the present invention can also be used as a raw material for epoxidized novolak resins, urethane resins by isocyanate conversion, triazine resins, and polyester resins.

Conventionally, for phenol novolac resins obtained by reacting bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl with phenols, isomers of bis (methoxymethyl) biphenyl compounds or mixtures thereof are used. A biphenylene-crosslinked phenol novolac resin is disclosed (Patent Document 1).
When these phenol novolak resins having biphenylene crosslinks are used as curing agents for epoxy resins, cured products having low water absorption (low moisture absorption), flame retardancy, mechanical properties, and adhesive properties can be obtained.

  However, the biphenylene-crosslinked phenol novolac resin according to the prior art has a problem that the curing rate is slower than the phenol novolac resin. If the curing speed is slow, the curing time becomes long, which adversely affects the productivity or production cost when used for each application. Therefore, there is a demand for a biphenylene-crosslinked phenol novolac resin that satisfies low water absorption (low hygroscopicity), flame retardancy and high heat resistance, and has a high curing rate.

Japanese Patent Laid-Open No. 08-143648

  The object of the present invention is to have a low water absorption (low hygroscopicity), heat resistance, flame retardancy, mechanical properties and adhesive properties, while the epoxy resin has a curing rate compared with the conventional biphenylene-crosslinked phenol novolac resin. It is to provide a fast biphenylene cross-linked phenol novolac resin.

  As a result of intensive studies to achieve the above object, the present inventor has found that a biphenylene cross-linked phenol novolak resin containing at least one dihydric phenol in phenols is effective, and has reached the present invention.

  That is, the present invention relates to a biphenylene-crosslinked phenol represented by the following general formula (2) comprising a reaction product of a biphenyl compound represented by the general formula (1) and a phenol mixture containing at least one dihydric phenol. It relates to novolac resin.

式中、Ｘは、炭素原子数１〜４のアルコキシル基またはハロゲン原子を表す、

In the formula, X represents an alkoxyl group having 1 to 4 carbon atoms or a halogen atom.

式中、Ｒ^１、Ｒ^２及びＲ^３は、それぞれ、同一でも異なっていてもよく、また、複数のＲ^１、Ｒ^２及びＲ^３は同一でも異なっていてもよく、置換又は非置換の炭素原子数１〜１０の直鎖又は分岐状アルキル基、置換又は非置換のアリール基を表し、ｐ１及びｐ３は０〜４の整数を表し、ｐ２は０〜３の整数を表し、ｎは０〜１５の整数を表し、ｍ１、ｍ２及びｍ３はそれぞれ１または２の整数を表し、複数のｍ２は同一でも異なっていてもよく、但し、ｍ１、ｍ２、ｍ３が全て１または全て２の場合は除く。

In the formula, each of R ¹ , R ² and R ³ may be the same or different, and a plurality of R ¹ , R ² and R ³ may be the same or different, and a substituted or unsubstituted carbon A linear or branched alkyl group having 1 to 10 atoms, a substituted or unsubstituted aryl group, p1 and p3 represent an integer of 0 to 4, p2 represents an integer of 0 to 3, and n represents 0 to 0 Represents an integer of 15, m1, m2, and m3 each represent an integer of 1 or 2, and a plurality of m2 may be the same or different, except when m1, m2, and m3 are all 1 or all 2. .

The biphenylene cross-linked phenol novolak resin obtained by the method of the present invention has a low water absorption (low hygroscopicity), heat resistance, flame retardancy, mechanical properties, and adhesive properties, but is more than the conventional biphenylene cross-linked phenol novolak resin. It is a resin with a fast curing rate of epoxy resin and can contribute to the improvement of productivity.
Moreover, as an application of this resin, using it as an epoxy resin by making it react with an epoxy resin hardening | curing agent and epichlorohydrin is mentioned, Furthermore, since a biphenylene crosslinking group is included, it can be used also as a flame retardant.

  Hereinafter, the present invention will be described in detail.

The phenols used in the present invention are compounds having one hydroxyl group on the benzene ring. Examples of the phenols include substituted or unsubstituted phenol, naphthol, and bisphenol. The substituents represented by R ¹ , R ^2, and R ³ in Formula (2) include those having 1 to 10 carbon atoms. Examples thereof include a linear or branched alkyl group and a substituted or unsubstituted aryl group. ^{1 to} 4 of these substituents may be substituted for R ¹ and R ³ and 1 to 3 may be substituted for R ² . Preferred alkyl groups include linear or branched alkyl groups of methyl, ethyl, propyl, butyl, hexyl and octyl. Specific examples include: phenol; cresol, ethylphenol, n-propylphenol, octylphenol, nonylphenol, phenylphenol, monosubstituted phenols; xylenol, methylpropylphenol, dipropylphenol, dibutylphenol, guaiacol, guetol, etc. Substituted phenols; trisubstituted phenols represented by trimethylphenol; naphthols such as naphthol and methylnaphthol; and bisphenols such as bisphenol, bisphenol A, and bisphenol F. These phenols may be used alone or in combination of two or more. Preferred phenols are unsubstituted phenol and meta-substituted linear or branched alkylphenols having 1 to 4 carbon atoms in view of the reactivity of the phenols, and more preferably phenol and m- Cresol.

The dihydric phenol used in the present invention is a compound having two hydroxyl groups on the benzene ring. Specific examples include resorcin, hydroquinone, and catechol. These dihydric phenols may be used alone or in combination of two or more. Resorcin is preferable.
Further, resorcin, hydroquinone, and catechol may have at least one linear or branched alkyl group having 1 to 10 carbon atoms or a substituted or unsubstituted aryl group, but preferably none. It is a substituted compound.
Further, the compounds contained in the dihydric phenol of the present invention include a group of compounds having one hydroxyl group on each benzene ring in the molecule, but a total of two hydroxyl groups, for example, a bisphenol compound group. Specific examples of the bisphenol compound group include bisphenol, bisphenol A, and bisphenol F.
These dihydric phenols may be used alone or in combination of two or more. Preferred are unsubstituted resorcin, hydroquinone and catechol, and more preferred is unsubstituted resorcin.

In the present invention, it is essential to use a mixture of phenols containing at least one component of dihydric phenol. This is a phenol mixture. The mixing ratio of phenols and dihydric phenols is not particularly limited. However, the content ratio of the dihydric phenol to 100 mol of the phenol mixture (total number of moles of phenol and dihydric phenol used) is preferably 5 to 80 mol. More preferably, it is 7-70 mol, More preferably, it is 10-50 mol.
Bivalent phenol alone can provide a biphenyl-crosslinked phenol novolac resin having a high curing rate, but is not preferred because it may make it difficult to remove impurities in the resin production process. Furthermore, the disadvantage that the water absorption rate is relatively high is not solved.
In a system containing no dihydric phenol, no effect can be found in improving the curing rate. Although there is no restriction | limiting in particular about the mixing method of phenols and dihydric phenol, Preferably what is necessary is just to mix at the time of preparation of reaction.

  Examples of the biphenyl compound represented by the following general formula (1) of the present invention include bis (alkoxymethyl) biphenyl and bis (halogenated methyl) biphenyl. Examples of these compounds include isomers of 4,4'-isomer, 2,2'-isomer, and 2,4'-isomer, and preferably 4,4'-isomer. There is no problem even if these isomers are used in combination of two or more.

ここで、アルコキシル基は、炭素原子数が１〜４の脂肪族直鎖の炭化水素のアルコキシル基が好ましく、具体的には、メトキシ、エトキシ、プロポキシ、ブトキシが挙げられ、取り扱いが容易であることから主にメトキシが使用される。
ハロゲン原子としては、フッ素原子、塩素原子、臭素原子、ヨウ素原子が挙げられるが、塩素原子が好ましく使用される。

Here, the alkoxyl group is preferably an aliphatic linear hydrocarbon alkoxyl group having 1 to 4 carbon atoms, and specifically includes methoxy, ethoxy, propoxy, butoxy, and is easy to handle. Mainly methoxy is used.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a chlorine atom is preferably used.

The isomer mixture of bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl represented by the above general formula (1) of the present invention is not particularly limited in terms of the combination and amount used, but 4, 4 It is preferable that the '-form is contained as a main component.
The crosslinking agent can be synthesized by adding it all at once or reacting it, or by adding it in portions. The batch addition at the time of charging is preferable.

  The synthesis catalyst of the present invention can be synthesized by condensation polymerization in the presence of organic acids such as oxalic acid, formic acid, acetic acid, and Friedel-Craft type catalysts such as sulfuric acid, p-toluenesulfonic acid, and diethyl sulfate. .

Specific production conditions of the phenol novolac resin represented by the general formula (2) of the present invention are as follows.
The total amount of dihydric phenol isomers described above or a mixture thereof and phenols, and the bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl isomer mixture used as a crosslinking agent or a mixture thereof Regarding the blending ratio of the mixture, the amount of each isomer of dihydric phenol or the mixture thereof and phenol is usually used for each isomer mixture of bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl. It may be 1.2 times or more in total. Preferably it is 1.3-5.5 times mole, More preferably, it is 1.4-4.5 times mole. When the amount is less than 1.2 times mol, the crosslinking proceeds and a phenol novolak resin suitable for the purpose of the present invention may not be stably obtained, which is not preferable. Moreover, when there are too many, unreacted raw materials increase and it is not economical.

The use amount of the synthesis catalyst used in the present invention is 0.001 to 0.5 parts by weight, preferably 0.001 to 0.5 parts by weight based on the total use amount of each isomer of dihydric phenol or a mixture thereof and phenols. It is suitably used in the range of 0.2 parts by weight, more preferably 0.001 to 0.1 parts by weight. When the amount used is small, the reaction rate is slow, and when the amount used is too large, the reaction proceeds rapidly and it becomes impossible to control the reaction.
In the case of bis (halogenated methyl) biphenyl, the generated hydrogen halide functions as a catalyst, so that it is not necessary to add a synthesis catalyst.

  The reaction temperature of the present invention is determined by blending each isomer of dihydric phenol to be used or a mixture thereof with phenols and each isomer mixture of bis (alkoxymethyl) biphenyl or bis (halogenated methyl) biphenyl as a bridging group. Although it depends on the ratio, it is usually 50 ° C to 200 ° C, preferably 70 to 180 ° C, more preferably 80 to 180 ° C. If it is too low, condensation polymerization will not proceed. If it is too high, it will be difficult to control the reaction, and it will be difficult to stably obtain the phenol novolac resin of the claims.

  Although the reaction time in the present invention depends on the reaction temperature, it is usually within 10 hours, and the addition condensation reaction, demethanol reaction or dehalogenation reaction is carried out.

  The reaction pressure in the present invention is usually carried out under normal pressure, but can also be carried out under slight pressure or reduced pressure.

The polystyrene-equivalent number average molecular weight (Mn) and weight average molecular weight (Mw) of the biphenylene-crosslinked phenol novolak resin represented by the general formula (2) obtained under the above reaction conditions range widely from low molecular weight to high molecular weight. Obtainable. However, considering physical properties and ease of handling, Mn is preferably 350 to 6800, more preferably 500 to 3500, and more preferably 500 to 3000. As Mw, 350-20000 are preferable, 500-15000 are still more preferable, 500-13000 are more preferable.
The repeating frequency n of the biphenylene crosslinking group of the biphenylene crosslinked phenol novolak resin represented by the general formula (2) obtained under the above reaction conditions is an integer from 0 to 15, preferably an integer from 0 to 12, Preferably it is an integer of 0-10.

The biphenylene cross-linked phenol novolak resin obtained in the present invention can be used as it is as a curing agent for an epoxy resin, or can be made into an epoxy resin by reacting with epichlorohydrin. Furthermore, it can also be set as the hardened | cured material using these.
Further, since it contains a biphenylene crosslinking group, it can also be used as a flame retardant.

  When the biphenylene-crosslinked phenol novolak resin of the present invention is used as a curing agent for an epoxy resin, the phenol novolak resin, the epoxy resin and a curing accelerator are mixed and obtained by curing in a temperature range of 100 ° C to 250 ° C. .

Examples of the epoxy resin include glycidyl ether type epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, triphenolmethane type epoxy resin, biphenyl type epoxy resin, and glycidyl. Examples thereof include an epoxy resin having two or more epoxy groups in the molecule, such as an ester type epoxy resin, a glycidylamine type epoxy resin, and a halogenated epoxy resin. These epoxy resins may be used alone or in combination of two or more.
Preferred epoxy resins include cresol novolac type epoxy resins and biphenyl type epoxy resins.

  As a hardening accelerator, the well-known hardening accelerator for hardening an epoxy resin with a phenol resin can be used. For example, organic phosphine compounds and boron salts thereof, tertiary amines, quaternary ammonium salts, tetraphenyl boron salts of imidazoles and the like can be mentioned, among which triphenylphosphine is preferable from the viewpoint of curability and moisture resistance. . In order to achieve higher fluidity, a heat-latent curing accelerator that exhibits activity upon heat treatment is preferred, and tetraphenylphosphonium derivatives such as tetraphenylphosphonium and tetraphenylborate are preferred.

With respect to the method of reacting the biphenylene-crosslinked phenol novolak resin of the present invention with epichlorohydrin to form an epoxy resin, for example, an excess of epichlorohydrin is added to the phenol novolak resin, and an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide is added. In the presence, a method of reacting in the range of 50 to 150 ° C., preferably 60 to 120 ° C. for about 1 to 10 hours can be mentioned. In this case, the usage-amount of epichlorohydrin is 2-15 times mole with respect to the hydroxyl equivalent of this phenol novolak resin, Preferably it is 2-10 times mole. Moreover, the usage-amount of the alkali metal hydroxide to be used is 0.8-1.2 times mole with respect to the hydroxyl equivalent of this phenol novolak resin, Preferably it is 0.9-1.1 times mole.
Regarding post-treatment after the reaction, excess epichlorohydrin is distilled off after completion of the reaction, the residue is dissolved in an organic solvent such as methyl isobutyl ketone, filtered, washed with water to remove inorganic salts, and then the organic solvent is distilled off. By leaving, the target epoxy resin can be obtained.

  The epoxy resin thus obtained and the biphenylene-crosslinked phenol novolak resin can be used as a curing agent to form a new epoxy resin composition.

  The obtained epoxy resin composition can be used by adding or reacting in advance with an inorganic filler, a release agent, a colorant, a coupling agent, a flame retardant, or the like, if necessary. In particular, when used for semiconductor sealing applications, the addition of an inorganic filler is essential. Examples of such inorganic fillers include amorphous silica, crystalline silica, alumina, calcium silicate, calcium carbonate, talc, mica, barium sulfate, etc., and particularly amorphous silica and crystalline silica. Etc. are preferable. Moreover, the compounding ratio of these additives may be the same as the ratio in a known semiconductor sealing epoxy resin composition.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to these examples. In the text, “parts” indicate all parts by weight.

Example 1
In a glass flask having a capacity of 1000 parts by volume equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 169.2 parts (1.8 moles) of phenol, 22 parts (0.2 moles) of catechol, 4, 4 ′ -112.6 parts (0.465 mol) of bismethoxymethylbiphenyl and 0.10 parts of 50% by weight sulfuric acid are placed in a four-necked flask, and at an internal temperature of 110 ° C to 140 ° C for 3 hours under a nitrogen stream, further 165 The mixture was reacted at 0 ° C. for 3 hours and cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 65.3 ° C. The number average molecular weight (Mn) in terms of polystyrene by gel permeation chromatographic analysis (hereinafter sometimes abbreviated as GPC) was 773, and the weight average molecular weight (Mw) was 920.

Example 2
In a glass flask with a capacity of 1000 parts by volume equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 169.2 parts (1.8 moles) of phenol, 22 parts (0.2 moles) of resorcin, 4, 4 ′ -112.6 parts (0.465 mol) of bismethoxymethylbiphenyl and 0.10 parts of 50% by weight sulfuric acid are placed in a four-necked flask, and at an internal temperature of 110 ° C to 140 ° C for 3 hours under a nitrogen stream, further 165 The mixture was reacted at 0 ° C. for 3 hours and cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 78.8 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 858, and the weight average molecular weight (Mw) was 1116.

Example 3
In a glass flask having a capacity of 1000 parts by volume equipped with a thermometer, a charging / distilling outlet, a condenser and a stirrer, 169.2 parts (1.8 moles) of phenol, 22 parts (0.2 moles) of hydroquinone, 4, 4 ′ -112.6 parts (0.465 mol) of bismethoxymethylbiphenyl and 0.10 parts of 50% by weight sulfuric acid are placed in a four-necked flask, and at an internal temperature of 110 ° C to 140 ° C for 3 hours under a nitrogen stream, further 165 The mixture was reacted at 0 ° C. for 3 hours and cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 70.6 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 778, and the weight average molecular weight (Mw) was 930.

Example 4
In a glass flask having a capacity of 1000 parts by volume equipped with a thermometer, a charging / distilling outlet, a condenser and a stirrer, 169.2 parts (1.8 moles) of phenol, 11 parts (0.1 moles) of hydroquinone, 11 parts of catechol ( 0.1 mol), 4,4′-bismethoxymethylbiphenyl (112.6 parts, 0.465 mol) and 50 wt% sulfuric acid (0.10 part) were placed in a four-necked flask and the internal temperature was 110 ° C. under a nitrogen stream. The mixture was reacted at ˜140 ° C. for 3 hours and further at 165 ° C. for 3 hours, and cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 70.9 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 725, and the weight average molecular weight (Mw) was 858.

Example 5
In a glass flask with a capacity of 1000 parts by volume equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 178.6 parts (1.90 mole) of phenol, 11 parts (0.10 mole) of resorcin, 4, 4 ' -112.6 parts (0.465 mol) of bismethoxymethylbiphenyl and 0.10 parts of 50% sulfuric acid were placed in a four-necked flask, and at an internal temperature of 110 ° C to 140 ° C for 3 hours under a nitrogen stream, further 165 ° C. For 3 hours and cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 74 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 811 and the weight average molecular weight (Mw) was 1005.

Example 6
94 parts by volume of phenol (1.0 mol), 110 parts by weight of resorcin (1.0 mol), 4, 4′-bis in a 1000-volume glass flask equipped with a thermometer, charging / distilling outlet, condenser and stirrer Methoxymethylbiphenyl (112.6 parts, 0.465 mol) and 50 wt% sulfuric acid (0.10 part) were placed in a four-necked flask, and the temperature was increased from 110 ° C to 140 ° C for 3 hours and further to 165 ° C under a nitrogen stream. For 3 hours and then cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 97 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 912, and the weight average molecular weight (Mw) was 1127.

Example 7
In a glass flask having a capacity of 1000 parts by volume equipped with a thermometer, a charging / distilling outlet, a condenser and a stirrer, 37.6 parts (0.4 mol) of phenol, 176 parts (1.6 mol) of resorcin, 4, 4 ′ -112.6 parts (0.465 mol) of bismethoxymethylbiphenyl and 0.10 parts of 50% by weight sulfuric acid are placed in a four-necked flask, and at an internal temperature of 110 ° C to 140 ° C for 3 hours under a nitrogen stream, further 165 The mixture was reacted at 0 ° C. for 3 hours and cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 102 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 1006, and the weight average molecular weight (Mw) was 1234.

Example 8
In a glass flask with a capacity of 1000 parts by volume equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 169.2 parts (1.8 moles) of phenol, 22 parts (0.2 moles) of resorcin, 4, 4 ′ -207.7 parts (0.858 mol) of bismethoxymethylbiphenyl and 0.15 part of 50% by weight sulfuric acid are placed in a four-necked flask, and at an internal temperature of 110 ° C to 140 ° C for 3 hours under a nitrogen stream, further 165 The mixture was reacted at 0 ° C. for 3 hours and cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 90.3 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 925, and the weight average molecular weight (Mw) was 1180.

Example 9
In a glass flask with a capacity of 1000 parts by volume equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 169.2 parts (1.8 moles) of phenol, 22 parts (0.2 moles) of resorcin, 4, 4 ′ -322.3 parts (1.29 mol) of bismethoxymethylbiphenyl and 0.15 part of 50% by weight sulfuric acid were placed in a four-necked flask, and at an internal temperature of 120 ° C to 135 ° C for 3.5 hours under a nitrogen stream, The mixture was further reacted at 165 ° C. for 3 hours and cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 125.6 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 2044, and the weight average molecular weight (Mw) was 11306.

Example 10
In a glass flask having a capacity of 1000 parts by volume equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 171.8 parts (1.83 moles) of phenol, 18.9 parts (0.17 moles) of resorcin, 96.8 parts (0.4 mol) of 4′-bismethoxymethylbiphenyl and 0.05 part of 50% by weight sulfuric acid were placed in a four-necked flask, and the temperature was 120 ° C. to 140 ° C. for 3 hours under a nitrogen stream. The mixture was further reacted at 165 ° C. for 3 hours and cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 73.0 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 822, and the weight average molecular weight (Mw) was 957.

Example 11
In a glass flask having a capacity of 1000 parts by volume equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 171.8 parts (1.83 moles) of phenol, 18.9 parts (0.17 moles) of resorcin, 113.16 parts (0.4 mol) of 4′-bismethoxychlorbiphenyl was placed in a four-necked flask and reacted under a nitrogen stream at an internal temperature of 120 ° C. to 140 ° C. for 3 hours, and further at 165 ° C. for 3 hours. Cooled to 95 ° C. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 78.0 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 882, and the weight average molecular weight (Mw) was 1171.

Comparative Example 1
In a glass flask having a capacity of 1000 parts by volume equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 188 parts (2 mol) of phenol, 112.6 parts of 4,4′-bismethoxymethylbiphenyl (0.465 mol) ) And 0.09 part of 50% by weight sulfuric acid are placed in a four-necked flask and allowed to react at an internal temperature of 110 ° C. to 120 ° C. for 2.5 hours and further at 165 ° C. for 3 hours under a nitrogen stream, and cooled to 95 ° C. did. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 68 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 753, and the weight average molecular weight (Mw) was 896.

Comparative Example 2
In a glass flask having a capacity of 1000 parts by volume equipped with a thermometer, a charging / distilling outlet, a condenser and a stirrer, 188 parts of phenol (2 moles), 140.3 parts of 4,4′-bismethoxymethylbiphenyl (0.579 moles) ) And 0.09 part of 50% by weight sulfuric acid are placed in a four-necked flask and allowed to react at an internal temperature of 110 ° C. to 120 ° C. for 2.5 hours and further at 165 ° C. for 3 hours under a nitrogen stream, and cooled to 95 ° C. did. After cooling, 250 parts of pure water of 90 ° C. or higher was added and washed with water. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure-steaming treatment. The softening point of the obtained resin was 74 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 915, and the weight average molecular weight (Mw) was 1191.

Comparative Example 3
In a glass flask with a capacity of 1000 parts by volume equipped with a thermometer, charging / distilling outlet, condenser and stirrer, 405.8 parts (3.689 mol) of 4,4′-bismethoxymethylbiphenyl 207.7 parts. (0.858 mol) and 0.10 parts of 50% by weight sulfuric acid were placed in a four-necked flask and reacted under a nitrogen stream at an internal temperature of 110 ° C. to 140 ° C. for 3 hours and further at 165 ° C. for 3 hours. Cooled to ° C. Thereafter, the internal temperature was raised to 160 ° C., and unreacted components were removed by a reduced pressure treatment. The softening point of the obtained resin was 95 ° C. The number average molecular weight (Mn) in terms of polystyrene by GPC was 891, and the weight average molecular weight (Mw) was 1038.

The analysis method of the resin and the curing agent obtained in the present invention is as follows.
Phenol novolac resin (1) Gel permeation chromatographic analysis: GPC measurement method • Model: HLC-8220, manufactured by Tosoh Corporation • Column: TSK-GEL H type G2000H × L 4 G3000H × L 1 G4000H × L 1 Measurement conditions: Column pressure 13.5 MPa
-Solution: Tetrahydrofuran (THF)
-Flow rate: 1 ml / min.
・ Measurement temperature: 40 ℃
・ Detector: Spectrophotometer (UV-8020)
・ RANGE: 2.56 WAVE LENGTH 254nm & RI
(2) Softening point • The sample is melted, filled into a copper ring, and cooled to room temperature.
-The ring filled with the sample is set in an automatic softening point measuring device (model: EX-719PD ELEX SCIENTIFIC CO., LTD.).
-Start the oil of the automatic softening point measuring device at a heating rate of 4 ° C / min.
・ Oil bath temperature when 3.5g steel ball passes the sensor is the softening point. (Average value of n = 2)
(3) ICI viscosity ・ Set the plate temperature of the ICI cone plate viscometer to 150 ° C.
・ Select the cone to be used according to the sample viscosity.
Place the sample on the center of the hot plate at 150 ° C., and further contact the cone on it.
・ 90 sec. Turn on the motor switch and read the value when the indicated value is stable.
-Let the average value of n = 2 be a viscosity value.
(4) Electric conductivity-Sample: 8.0 ± 0.1 g is accurately weighed in a 100 ml plastic bottle, and the electric conductivity; 2.0 μS / cm or less ion exchange water;
Extract in a hot air circulation dryer at 95 ° C. for 20 hours.
・ After 20 hours, take it out of the dryer, immerse it in a low temperature constant temperature water bath and cool to 25 ° C.
・ Soak the electrode part of the solution conductivity meter (manufactured by Kyoto Electronics Co., Ltd.) in the extraction water and wait until the electric conductivity value is stabilized.
・ The value at the time of stabilization is the electrical conductivity.
(5) OH equivalent (Outline: Method of acetylating with acetyl chloride, decomposing excess acetyl chloride with water, and titrating with alkali)
-Weigh accurately 1 g of sample, add 1,4-dioxane; 10 ml and dissolve.
-After confirming dissolution, add 1.5 ml / L acetyl chloride / anhydrous toluene solution; 10 ml, and cool to 0 ° C.
-Pyridine; add 2 ml and react in water bath at 60 ± 1 ° C for 1 hour.
-After the reaction, cool and add pure water; 25 ml, and mix well to decompose acetyl chloride.
Add acetone; 25 ml, phenolphthalein.
-Titration is performed using 1 mol / L-potassium hydroxide until the sample solution turns reddish purple.
・ Measure the blank (no sample) at the same time by the above operation.
Calculate by the following formula.
OH equivalent [g / eq. ] = (1000 × W) / (f × (BA))
Where W: sample weight [g]
f: Factor of 1 mol / L-potassium hydroxide = 1.002
B: 1 mol / L-potassium hydroxide amount [ml] required for blank measurement
A: 1 mol / L-potassium hydroxide amount [ml] required for sample measurement
Curing agent (6) Water absorption measurement-Cast at 150 ° C x 5 hours + 180 ° C x 3 hours and cure to the following size.
Size: (φ50 ± 1) × (3 ± 0.2) (diameter × thickness: mm)
・ Wipe the surface well and measure the sample weight.
• Place in a 100 ml sample bottle and add 80 ml of pure water.
・ Absorb water at 95 ° C. for 24 hours in a hot air circulation dryer.
・ After 24 hours, take it out of the dryer, immerse it in a low temperature water bath and cool to 25 ° C.
・ After cooling, wipe off the water adhering to the surface and measure the weight.
・ Calculate the water absorption rate by the following formula.
Water absorption [%] = ((B−A) / A) × 100
A: Weight before water absorption [g]
B: Weight after water absorption [g]
(7) Measurement of glass transition temperature (Tg)-A sample cast and cured at 150 ° C x 5 hours + 180 ° C x 3 hours is cut to the following size.
Size: (50 ± 1) × (40 ± 1) × (100 ± 1) (length × width × height; mm)
Measurement device; the sample was set in TMA-60 (manufactured by SHIMADZU), measured in an _{N 2} atmosphere.
-Temperature rising rate: 3 ° C / min. Measured to 350 ° C., the temperature of the inflection point is obtained and set as the glass transition temperature (Tg).
(8) Measurement of cured product mechanical properties (elastic modulus, energy, displacement, stress, strain) ・ Cut the sample cast and cured at 150 ° C. × 5 hours + 180 ° C. × 3 hours into the following sizes.
・ Size: (75 ± 1) × (6 ± 1) × (4 ± 1) (length × width × thickness: mm)
・ Measuring device: Autograph (Model: AG-5000D manufactured by SHIMADZU)
Head speed: 10 mm / min. Distance between two points: 50 mm Perform a compression bending test at room temperature.

  Table 1 shows the physical properties of the phenol novolac resins synthesized according to Examples 1 to 11 and Comparative Examples 1 to 3.

  Each phenol novolak resin in Table 1 was used as a curing agent, EOCN-1020-70 (epoxy equivalent 197 g / eq) manufactured by Nippon Kayaku Co., Ltd. was used as an epoxy resin, and triphenylphosphine was used as a curing accelerator. Blended at the same equivalent ratio as the above epoxy resin, heated to 150 ° C, melt mixed, cast into a mold heated to 150 ° C after vacuum defoaming, 5 hours at 150 ° C, 3 hours at 180 ° C Cured to obtain a cured epoxy resin. Table 2 shows the composition and physical properties of the obtained cured epoxy resin.

  Each phenol novolak resin in Table 1 was used as a curing agent, and Epicoat YX-4000 (epoxy equivalent 187 g / eq) manufactured by Japan Epoxy Resin Co., Ltd. was used as an epoxy resin, and triphenylphosphine was used as a curing accelerator. Blended at the same equivalent ratio as the above epoxy resin, heated to 150 ° C, melt mixed, cast into a mold heated to 150 ° C after vacuum defoaming, 5 hours at 150 ° C, 3 hours at 180 ° C Cured to obtain a cured epoxy resin. Table 3 shows the composition and physical properties of the obtained cured epoxy resin.

According to the present invention, while having low water absorption (low hygroscopicity), heat resistance, flame retardancy, mechanical properties, and adhesive properties, the curing rate of epoxy resins is higher than that of conventional biphenylene-crosslinked phenol novolac resins. Fast biphenylene cross-linked phenol novolac resins can be provided.
Moreover, the biphenylene bridge | crosslinking phenol novolak resin of this invention can be used as an epoxy resin by making it react with epichlorohydrin, Furthermore, since it contains a biphenylene bridge | crosslinking group, it can also be used as a flame retardant.

Claims (5)

A biphenyl compound represented by the following general formula (1), Ri formed from the reaction product of a phenol mixture at least one component containing a dihydric phenol, wherein, with respect to phenol mixture 100 moles, dihydric phenols The biphenylene bridge | crosslinking phenol novolak resin represented by following General formula (2) which is 5-80 mol .

In the formula, X represents an alkoxyl group having 1 to 4 carbon atoms or a halogen atom.

In the formula, each of R ¹ , R ² and R ³ may be the same or different, and
A plurality of R ¹ , R ² and R ³ may be the same or different and each represents a substituted or unsubstituted linear or branched alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group, p1 and p3 represent an integer of 0 to 4, p2 represents an integer of 0 to 3, and n represents 0.
Represents an integer of ˜15, m1, m2 and m3 each represent an integer of 1 or 2,
A plurality of m2 may be the same or different, except when m1, m2, and m3 are all 1 or all 2. The hardening | curing agent for epoxy resins which consists of a biphenylene bridge | crosslinking phenol novolak resin of Claim 1 . An epoxidized novolac resin obtained by epoxidizing the biphenylene-crosslinked phenol novolac resin according to claim 1 . The epoxy resin composition formed by mix | blending the biphenylene bridge | crosslinking phenol novolak resin and epoxy resin of Claim 1 . Hardened | cured material which consists of an epoxy resin composition of Claim 4 .