JPS6381118A - Novolak type epoxy resin of phenols - Google Patents

Abstract

PURPOSE:To obtain the titled readily handleable resin, containing tetranuclear skeletal phenols novolak type epoxy compound expressed by a specific formula and binuclear skeletal phenols novolak type epoxy compound in respective specific amounts, having improved operability and capable of giving cured articles having high heat resistance. CONSTITUTION:A resin containing >=30wt%, preferably >=35wt% tetranuclear skeletal phenols novolak type epoxy compound expressed by the formula (R is H or <=10C10 alkyl; n is 1-3) and <=15wt%, optimally 5wt% binuclear skeletal phenols novolak type epoxy compound.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention comprises a tetranuclear phenolic novolac type epoxy compound containing 30% by weight or more, and a dinuclear phenolic novolac type epoxy compound containing 15% by weight. The present invention relates to the following phenolic novolac type epoxy resin.

[Conventional technology]

In general, epoxy resins are widely used in electrical equipment materials, paints, adhesives, civil engineering and construction materials, and various composite materials, and depending on the application, they have heat resistance and chemical resistance.

Although properties such as posability and pentabularity are required, there is no known material that satisfies both of these properties at the same time.

Diglycidyl ether to bisphenol is widely used as an epoxy resin because it is liquid at room temperature and can be easily mixed with other curing agents, but because it is bifunctional, the heat distortion temperature of the cured product is 150 It cannot be said to have heat resistance, as it is as low as ℃. Phenolic novolac type epoxy resins with improved heat resistance are used in fields where heat resistance is required. Among these, o-cresol novolak epoxy resin is used as a sealant resin for ICs.

[Problem that the invention seeks to solve]

However, the commonly used 0-cresol novolac epoxy resin has a wide molecular weight distribution, and in particular, low molecular weight compounds such as binuclear bodies contained in the epoxy resin may affect the heat resistance of the cured product. lower. On the other hand, in the case of epoxy resins with a reduced content of binuclear bodies, the heat resistance of the cured product improves, but since conventional epoxy resins have a wide molecular weight distribution, the molecular weight distribution is inevitably biased toward the polymer side, and the raw material novolac The softening temperature of the epoxy resin increases and the melt viscosity increases, resulting in poor workability and limited use.

[Means for solving problems]

As a result of various studies on epoxy resins, the present inventors found that 2
Phenolic novolac type epoxy resin with very few nuclei and narrow molecular weight distribution mainly consisting of tetranuclear bodies has a low softening temperature and melt viscosity, but when made into a cured product, it has low heat resistance. The present invention was completed based on the discovery that it has excellent properties.

(In the formula, R is a hydrogen atom or an alkyl group having 10 or less carbon atoms, and n represents 1.2 or 3.) 4
The present invention relates to a phenolic novolac type epoxy resin containing 30% by weight or more of a nuclear phenolic novolac type epoxy compound and 15% by weight or less of a dinuclear phenolic novolac type epoxy compound.

The epoxy resin of the present invention has a lower softening temperature than conventional phenolic novolac epoxy resins, and the cured product has high heat resistance.

The epoxy resin of the present invention contains 30% by weight or more of the epoxy compound of general formula (T), and the preferable content of the epoxy compound of general formula +1) is 35% by weight or more.

The amount of the dinuclear phenol novolac type epoxy compound contained in the epoxy resin of the present invention is 15% by weight or less, more preferably 10% by weight or less, particularly preferably 5% by weight or less. Examples of these dinuclear phenol novolac type epoxy compounds include compounds represented by formula 1+81.

If the amount of the dinuclear phenol novolac type epoxy compound is too large, the cured product will not have sufficient heat resistance.

In the epoxy resin of the present invention, the components other than the tetranuclear and dinuclear phenolic novolac type epoxy compounds are polynuclear phenolic novolac type epoxy compounds such as pentanuclear, hexanuclear, and octanuclear.

The epoxy resin of the present invention containing an epoxy compound represented by the general formula (T) as a main component has a general formula (where Rln
has the same meaning as above. ) containing 30% by weight or more of a tetranuclear phenolic novolac and 15% by weight or less of a dinuclear phenolic novolak, which has the general formula (m) (wherein, X represents a halogen atom). It can be easily obtained by reacting an epino-rogen compound represented by the following formula in the presence of a basic compound.

The alkyl group represented by R in the general formulas CI+ and I includes methyl group, ethyl group, n-propyl group,
Examples include i-propyl group, n-butyl group, t-butyl group, and n-nonyl group.

Particularly preferable examples of R include a hydrogen atom and an alkyl group having 1 to 6 carbon atoms.

Specifically, the tetranuclear phenolic novolak represented by the general formula I includes a tetranuclear body of 0-cresol, a tetranuclear body of 0-cresol and phenol, 0-cresol and m
-Cresol tetranuclear, 0-cresol and p-cresol tetranuclear, 0-cresol and pt-butylcresol tetranuclear, o-cresol p-n-nonylphenol tetranuclear, 0- cresol and 2.4- and/or 2
．． Examples include tetranuclear bodies of 6-xylenol.

In the general formula (m), examples of the halogen atom represented by X include C1, Br, I, etc.
) Specific examples of the compound include epichlorohydrin, shrimp bromohydrin, shrimp iodohydrin, etc. Although mixtures of these can also be used, epichlorohydrin is preferably used industrially.

The reaction between the phenolic novolac and the shrimp halogen compound represented by the general formula (m) can be carried out by a known method.

A phenolic novolac and a shrimp halogen compound in an excess molar amount relative to the hydroxyl equivalent of the phenolic novolac are combined with a quaternary ammonium salt such as tetramethylammonium chloride, tetramethylammonium bromide, triethylammonium chloride, or sodium hydroxide,
The reaction is carried out in the presence of an alkali metal hydroxide such as potassium hydroxide, and when a quaternary ammonium salt is used, the reaction stops at the stage of the ring-opening addition reaction, so the above alkali metal hydroxide is then added. Perform a ring-closing reaction.

In addition, when reacting by adding an alkali metal hydroxide from the beginning, the ring-opening addition reaction and ring-closing reaction are performed at once.

The proportion of the shrimp halogen compound used is generally 1 to 50 mol, preferably 3 to 15 mol, per 1 hydroxyl equivalent of the phenol novolak.

The amount of alkali metal hydroxide used is usually in the range of 0.8 to 1.5 mol, preferably 0.9 to 1.3 mol, per 1 hydroxyl group of the phenolic novolac. When used, the amount used is usually 0.001 to 1 mol, preferably 0.005 to 0.5 mol, based on the hydroxyl equivalent of the phenolic novolak.

The reaction temperature is usually 30-130°C, preferably 40-120°C.
It is ℃.

Furthermore, the reaction can be allowed to proceed while removing water produced in the reaction from the reaction system.

After the completion of the reaction, by-product salts are removed by washing with water, filtration, etc., and excess shrimp halogen compound is distilled off to obtain an epoxy resin.

The phenolic novolak containing 30% by weight or more of tetranuclear phenolic novolak and 15% by weight or less of dinuclear phenolic novolak used in the above reaction is 1
It can be manufactured as follows. That is, the general formula (
(2) 0-cresol dinuclear dimethylol compound [hereinafter referred to as compound (IV)] and the general formula (2) (wherein,
R and n have the same meanings as above. ) can be produced by dehydration condensation of phenols represented by the following in the presence of an acid catalyst. As acid catalysts, hydrochloric acid, sulfuric acid, phosphoric acid,
p-) Luenesulfonic acid, oxalic acid, etc. can be used, and the acid catalyst is preferably used in an amount of 0.1 to 30% by weight of the compound ([V)]. In addition, phenols have a 2
It is preferable to use up to 15 moles. What is the reaction?

It can be carried out without a solvent or in a solvent such as benzene, toluene, methyl in butyl ketone, etc.

The reaction temperature is preferably in the range of 20 to 150°C.

After the reaction is completed, the used catalyst is removed by washing with water, etc., and the solvent and excess phenols are distilled off under reduced pressure to obtain the above-mentioned phenolic novolak containing 30 or more phenolic novolaks. Can be done.

When phenolic novolacs are produced by a method of reacting phenolic toformaldehyde such as 0-cresol, which is a conventional method for producing phenolic novolaks, phenolic novolacs with a wide molecular weight distribution are obtained.
Phenolic novolaks such as those mentioned above cannot be obtained.

The epoxy resin of the present invention can be used alone or in combination with other epoxy compounds, as well as a polyamine curing agent such as aliphatic polyamine, aromatic polyamine, polyamide polyamine, hexahydrophthalic anhydride, Curing with acid anhydride curing agents such as methyltetrahydrophthalic anhydride, phenol curing agents such as phenol novolak and cresol novolak, Lewis acids such as boron trifluoride or their salts, and curing agents such as dicyandiamide. Can be done. or.

Various compounding agents such as a curing accelerator and an inorganic or organic filler can be added as necessary.

The epoxy resin of the present invention can be used in a wide range of fields where heat resistance is required. Specifically, insulating materials, laminate sealing materials, molding materials, composite materials, etc. can be exemplified.

〔Example〕

The present invention will be explained below with reference to Examples.

Synthesis Example 1゜O-cresol 2 is placed in a glass container equipped with a thermometer and a stirrer.
Nuclear dimethylol compound [Compound ■] 200g (0,6
9 mol) and 750 g (6.9 mol) of 0-cresol were charged and stirred at room temperature under a nitrogen atmosphere.

p-) Luenesulfonic acid 2 g (o-Frezy □
(1.0% by weight based on the dinuclear dimethylol compound) was gradually added to the solution, taking care not to generate heat so that the liquid temperature did not exceed 50°C.

After the addition, the mixture was heated to 50°C on an oil bath and reacted for 2 hours.
500 ml of methyl isobutyl ketone was added, and the mixture was transferred to a 210 separatory funnel and washed with water. After washing with water until the washing water shows neutrality,
The organic layer was concentrated under reduced pressure to obtain a pale yellow viscous substance (306 g of At
I got it. This solidified when left at room temperature. The softening temperature of the product (JIS K2425 ring and ball method) is 81.0.
The hydroxyl equivalent (g/mol) was 119 at °C.

Synthesis Example 2 In Synthesis Example I, the reaction was carried out in the same manner as in Synthesis Example 1 except that 650 g (6.91 mol) of phenol was used instead of 0-cresol to obtain 1288 g of a yellow solid (B.
The softening temperature of Bl was 84.2°C. In Synthesis Example 3, 1035 g (6.9 mol) of pt-butylphenol was used instead of 0-cresol, and
The reaction was carried out in the same manner as in Synthesis Example 1 except that 1500 ml of methyl isobutyl ketone was added as a solvent and the reaction temperature was set to 80° C. to obtain 36] g of a yellow solid (C). The softening temperature of the product (0) was 103°C.

Synthesis Example 4 Synthesis Example 1 except that 842 g (6.9 mol) of 2゜6-xylenol was used instead of 0-cresol in Synthesis Example 1, 1500 ml of methyl isobutyl ketone was added as a solvent, and the reaction temperature was 80°C. A yellow solid (335 g of DI) was obtained by reacting in the same manner as above.

The softening temperature of product 0 is 82.7°C and the hydroxyl equivalent (g/
mol) was 127.

Synthesis Example 5 A reaction was carried out in the same manner as in Synthesis Example except that 298 g (2.76 mol) of 0-cresol was used and 600 ml of methyl isobutyl ketone was added as a solvent to obtain 313 g of a yellow solid (2).

The softening temperature of the product [F] was 88.3°C, and the hydroxyl equivalent (g
/mol) was 120.

Products obtained in Synthesis Examples 1 to 5 (At, (Bl,
(C1.

(2) and D were analyzed by GPC, and the contents of tetranuclear and dinuclear phenolic novolacs were as follows.

(B) 8.0 0.8
(C) 70 0.1 or less (
D) 85 2.3 (E
) 54 1.1 The analysis conditions are as follows.

GPC device: Takasugi Seisakusho (Column: TSK-G-3000XL (1 piece) +
TSK-G-2000XL (2 bottles) Solvent: Tetrahydrofuran II? lI/min Detection UV (254 nm) Example 1゜With thermometer, stirring device, dropping funnel and produced water separation device ■! Into a reactor, 150 g of the product obtained in Synthesis Example 1 (Al (hydroxyl group equivalent (g/mot) ) ] 9 ) and 475 g of epichlorohydrin were charged, and the reactor was replaced with nitrogen, followed by 106.8 g of a 48% sodium hydroxide water bath solution. 5
It dripped over time.

During dropping, the reaction temperature was 60°C and the pressure was 100 to 150 mmH.
Under the conditions of g, the produced water and the water in the aqueous sodium hydroxide solution were continuously removed from the reaction system by azeotropy with epichlorohydrin, and epichlorohydrin was returned to the system.

Then, after recovering excess unreacted epichlorohydrin under reduced pressure, 500 ml of methoxy-isobutyl ketone was added.
The mixture was washed with 100 ml of water until the aqueous layer became neutral. The methyl isobutyl ketone layer was concentrated under reduced pressure,
210.7 g of pale yellow solid (AI) was obtained.

Softening temperature of product (A1) (JIS K2425) 54
．． The epoxy equivalent (g/mol) at 0°C was 83.

When product (A1) was analyzed by GPC using tetrahydrofuran (THF) as a solvent, the molecular weight distribution curve shown in FIG. 1 was obtained (the analysis conditions were the same as in the synthesis example).

Under these conditions, the retention time at which bisphenol F appears is 24.7 minutes, and the retention time of the main peak corresponds to the retention time of a tetranuclear substance having four benzene nuclei, and from Figure 1, the composition amount of the main peak is 53.
% by weight.

In the mass spectrum (FAB-MS) of product (A1), M
692 was obtained, it was found that the main component was a component having the following structure.

(Molecular weight: 692) Also, from FIG. 1, it was found that the product (A1) contained 1.7% by weight of a dinuclear phenolic novolac type epoxy compound.

Example 2 The reaction was carried out in the same manner as in Example 1, except that the product (B) (hydroxyl group equivalent (g/mo+) 11z) l, zg obtained in Synthesis Example 2 was used instead of product (8). Yellow solid (Bl) 202
I got g.

The softening temperature of the product (B1) was 50.2 °C and the epoxy equivalent (g/mol) was 176.

Figure 2 shows the molecular weight distribution curve of the product (Bl) obtained by GPC analysis (the analysis conditions are the same as the synthesis example), and the retention time of the main beak corresponds to the retention time of a tetranuclear body with four benzene nuclei. , the composition amount of the main peak was 61% by weight.

In the mass spectrum (FAB-MS) of product (B1), M
From the fact that 7C3 was obtained, it was found that the main component was a component having the following structure.

(Molecular weight: 664) Also, from FIG. 2, it was found that the product (Bl) contained 1.3% by weight of a dinuclear phenol novolac type epoxy compound.

Example 3゜A yellow solid ( C1) 231g was obtained.

The product (CI) had a softening temperature of 65.6° C. and an epoxy equivalent (g/mol) of 215.

Figure 3 shows the molecular weight distribution curve of the product (CI) by GPC analysis (analysis conditions are the same as the synthesis example), and the retention time of the main beak is 4.
This corresponds to the retention time of the core, and the composition amount of the main beak was 65% by weight.

Mass spectrum (FAB-MS) of product (CI)
From the fact that M''776 was obtained, it was found that the main component was a component having the following structure.

(Molecular weight: 776) Also, from FIG. 3, the content of the dinuclear phenol novolac type epoxy compound in the product (C1) was 0.1% by weight or less.

Example 4 159 g (of the product obtained in Synthesis Example 4) instead of the product
The reaction was carried out in the same manner as in Example I except that hydroxyl group equivalent (g/mol) 127) was used to form a yellow solid (DI) 2 ]
8 g was obtained.

The softening temperature of the product (DI) was 52.3°C, and the epoxy equivalent (g/mol) was 184.

Figure 4 shows the molecular weight distribution curve of the product (D]) obtained by GPC analysis (analysis conditions are the same as the synthesis example), and the retention time of the main beak corresponds to the retention time of a tetranuclear substance having four benzene nuclei. The composition amount of the main beak was 75% by weight.

The mass spectrum (FAB-MS) of the product (D]) showed that M720 was obtained, indicating that the main component was a compound having the following structure.
D]) was found to contain 2.0% by weight of a dinuclear phenolic novolac type epoxy compound.

Example 5゜150 g of the product (E) obtained in Synthesis Example 5 instead of the product prisoner
The reaction was carried out in the same manner as in Example 1 except that (hydroxyl equivalent: 120) was used to obtain 209 g of a yellow solid (El).

The softening temperature of the product (El) was 58.6°C, and the epoxy equivalent (g/mol) was 86.

FIG. 5 shows the molecular weight distribution curve of the product (El) obtained by GPC analysis (analysis conditions are the same as in the synthesis example). The main beak retention time was the same as in Example 1, but
The content of the polymer compound was larger than in Example 1, and the composition amount of the main beak was 37% by weight.

Further, from FIG. 5, it was found that the product (El) contained 2.4% by weight of a dinuclear phenol novolac type epoxy compound.

Reference Example 1゜Phenol novolac (Nippon Kayaku ■
Products (AI), (Bl), (CI) whose main component is the tetranuclear phenolic novolac type epoxy compound obtained in Example 1.2, 3.4 and 5 (softening temperature: 85°C)
, (DI), and (El) were blended and heated and cured using 2-methylimidazole as a catalyst.

As a comparative example, the following commercially available 0-cresol novolak type epoxy resin was used in place of the products (A1) to (El) obtained in Examples 1.2.3.4 and 5 in the proportions shown in Table 1. It was heated and cured.

EOCN 1020: Manufactured by Nippon Kayaku ■, containing half the amount (g/mol) of epoxy [: The molecular weight distribution curve by GPC is shown in Figure 6 (analysis conditions are the same as the synthesis example)] EOCN102S: Manufactured by Nippon Kayaku ■, epoxy Toi (g/
mo+) 212, softening temperature 51.6°C, 14 nuclear bodies and 2
Contains 12, 5, and 16.6% by weight of nuclear bodies, respectively.

Epoxidized product of bisphenol F (E-BisF) manufactured by Nippon Kayaku ■, epoxy equivalent (g/mol) 168,
The glass transition temperature (Tg) and heat distortion temperature (HDT) of the cured product in a liquid state or higher were measured, and the results are shown in Table 1. As is clear from Table 1, when the phenolic novolac type epoxy resin of the present invention is used, the resulting cured product has excellent heat resistance.

〔Effect of the invention〕

The phenolic novolac type epoxy resin of the present invention has a narrower molecular weight distribution and lower softening temperature than conventional ones, so it is easy to handle and has excellent workability, and the cured product obtained using it has excellent heat resistance. ing.

[Brief explanation of the drawing]

Figures 1 to 6 show the products obtained in Examples 1 to 5 (A
I), (Bl), ((j), (DI), (El), and molecular weight distribution curves of EOCNI020 used for comparison.

Claims (1)

[Claims] Represented by the general formula ▲ Numerical formulas, chemical formulas, tables, etc. 30% by weight of tetranuclear phenolic novolac type epoxy compound
A phenolic novolac type epoxy resin containing the above, and the amount of the dinuclear phenolic novolac type epoxy compound being 15% by weight or less.