JPH044326B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a new epoxy resin and a method for producing the same. More specifically, the present invention relates to an epoxy resin which is a glycidyl etherified product of 2,2'-dihydroxybiphenyl (hereinafter abbreviated as 2,2'-DOB) formaldehyde resin, and a method for producing the same. Epoxy resin is a general term for compounds having at least two or more epoxy groups in one molecule, and although many compounds have been published in the literature, their practical use is limited. For example, so-called bisphenol A type epoxy resin obtained from bisphenol and epichlorohydrin is widely used as an industrially excellent synthetic resin in fields such as paints, electricity, civil engineering, architecture, and adhesives. However, since bisphenol A type epoxy resin can only contain two glycidyl ether groups in one molecule, the crosslinking density during curing is relatively low, and the heat resistance and water resistance of the cured product are still not satisfactory. It's not something you can do. In recent years, especially in the electrical and electronic fields,
Epoxy resins with even better heat resistance, moisture resistance, water resistance, and electrical properties are expected to emerge. As a result of intensive studies to develop an epoxy resin that satisfies the above requirements, the present inventors found that 2,2'-
The present inventors have discovered that a new epoxy resin, which is a glycidyl etherified product of DOB/formaldehyde resin, satisfies the above-mentioned requirements and has completed the present invention. That is, the present invention is based on formula (1) (In the formula, n represents a number from 0 to 3.) and 2,2'-DOB
and formaldehyde in the presence of an acid catalyst, and 1-halo-2,3-epoxypropane is reacted in the presence of an alkali. A manufacturing method is provided. The epoxy resin according to the present invention solves the drawbacks of conventional epoxy resins, and has excellent heat resistance, moisture resistance, water resistance,
Because of its excellent electrical properties, it can be widely used in fields where epoxy resins have traditionally been used, and is particularly useful in the electronic and electrical industry fields. In producing the epoxy resin of the present invention, 2.
2′-DOB formaldehyde resin is 2,2′-
It can be easily produced by reacting DOB and formaldehyde in the presence of an acid catalyst. Examples of acid catalysts include mineral acids, aliphatic carboxylic acids, aromatic carboxylic acids, aliphatic sulfonic acids, and aromatic sulfonic acids. The amount of these catalysts used is 0.5 to 10% by weight based on 2,2'-DOB, usually 1
~5% by weight. The amount of formaldehyde used is 0.01 to 10 mol, preferably 0.2 to 4 mol, per 1 mol of 2,2'-DOB. If the amount of formaldehyde used is less than 0.01 molar ratio, the yield of 2,2'-DOB/formaldehyde resin will be low, while if it exceeds 10 molar ratio, the molecular weight of 2,2'-DOB/formaldehyde resin will increase. If too much is used, it becomes difficult to dissolve in toluene, ketones or epichlorohydrin, and therefore it becomes difficult to obtain the industrially advantageous epoxy resin of the present invention. The reaction between 2,2'-DOB and formaldehyde can be carried out in the absence of a solvent, but is preferably carried out in the presence of a solvent such as water or an inert organic solvent such as benzene or toluene. The reaction temperature is 50 to 200°C, preferably 70 to 130°C, and it is particularly preferable to carry out the reaction under azeotropy between a solvent such as benzene or toluene and water while separating water. The reaction time is 1 to 6 hours, usually 2 to 4 hours. After the reaction is completed, the product is washed with water to remove the catalyst to obtain 2,2'-DOB/formaldehyde resin. The 2,2'-DOB formaldehyde resin thus obtained is then 1-halo-2,3-
Epoxidize by reacting with epoxypropane in the presence of an alkali. 1-halo-2,3 used in epoxidation reaction
-1-chloro-2,3 as epoxypropane
-Epoxypropane is industrially advantageous and is usually 1 to 20 mol, preferably 5 to 7 mol per equivalent of hydroxyl group in the 2,2'-DOB/formaldehyde resin.
mole used. Examples of the alkali used in the epoxidation reaction include sodium hydroxide and potassium hydroxide, and it is usually used in an amount of 0.9 to 1.5 equivalents, preferably 1.0 to 1.2 equivalents, per equivalent of hydroxyl group in the 2,2'-DOB/formaldehyde resin. . The reaction temperature is 50 to 200°C, preferably 70 to 130°C, and the reaction is usually carried out at the reflux temperature of 1-halo-2,3-epoxypropane. The reaction time is 3 to 10 hours, usually 4 to 7 hours. In this epoxidation reaction, it is preferable to coexist a catalyst such as a quaternary ammonium compound. After the reaction is complete, carry out the usual post-treatment to remove excess 1-
The desired epoxy resin can be obtained by recovering halo-2,3-epoxypropane, removing inorganic salts, topping, and the like. The epoxy resin obtained in this way is 2,
A compound mainly consisting of a methylene bridge of 2'-bis(2,3-epoxypropoxy)biphenyl with formula (1)
It has a structural formula of 150 g/eq to 400 g/eq (preferably 150
g/eq) Softening point by R&B method is 30℃~200℃
(preferably 50°C to 150°C). Next, the present invention will be specifically explained using examples.
In the examples, % indicates weight %. Example 1 2,2'-DOB 186g (1.0 mol), benzene 186
ml, 80% paraformaldehyde 12g (0.3 mol)
and 1.86g of para-toluenesulfonic acid, 84
The condensation polymerization reaction was carried out at ~89°C for 4 hours while removing water from the system. After washing the reaction mixture three times with 200 ml of warm water each time, benzene was distilled and recovered to obtain 188 g of a pale yellow resinous substance. This resinous material had a softening point of 90° C. and a hydroxyl value of 580 mgKOH/g. Also, from NMR, this resinous material has a δ value of 3.8~
The presence of methylene groups can be confirmed in the range of 4.2 ppm,
Phenyl groups can be confirmed in the range of 6.8 to 7.4 ppm.
To 150 g of the 2,2'-DOB/formaldehyde resin thus obtained, 925 g (10
mol), 1 g of triethylbenzylammonium chloride, and 50% aqueous sodium hydroxide solution
127 g (1.6 mol) was added and heated under ECH reflux conditions, and the mixture was reacted for 4 hours while removing water from the system. Furthermore, ECH is distilled and recovered under reduced pressure conditions.
The residue was dissolved in 1000 ml of toluene, 300 g of a 3% aqueous sodium hydroxide solution was added, the mixture was continuously stirred at 86 to 89° C. for 1 hour, and the operation of standing still and separating the liquids was repeated twice. Then 1% monosodium phosphate aqueous solution 300
The mixture was stirred at 83 to 86°C for 30 minutes, allowed to stand, and after liquid separation, the organic layer was washed twice with 300 ml of water/time. After distilling and recovering toluene from the organic layer, low-boiling substances were distilled off at 150° C. under reduced pressure conditions of 10 mmHg to obtain 226 g of pale yellow resin. Table 1 shows the properties of this product.
Shown below. Example 2 2,2′-DOB 186 g (1.0 mol), benzene 186
ml, 80% paraformaldehyde 17 g (0.45 mol),
and 1.86 g of para-toluenesulfonic acid were mixed to obtain 176 g of a pale yellow resinous substance in the same manner as in Example-1. The softening point of this resinous material is 117℃, and the hydroxyl value is 577.
It was mgKOH/g. In addition, the δ value from NMR
Methylene groups were confirmed at 3.8 to 4.2 ppm, and phenyl groups were confirmed at 6.8 to 7.4 ppm. Thus obtained 2,2′−
925g (10
mol) of ECH, 1 g of triethylbenzylammonium chloride, and 127 g (1.6 mol) of a 50% aqueous sodium hydroxide solution were added, and 208 g of a pale yellow resin was obtained in the same manner as in Example-1. The properties of this product are shown in Table-1.

【table】

[Table] Epoxy equivalent hydrochloric acid-dioxane
Method reference example 1 60 g of phenol novolac resin and 2-phenyl-4 were added to 100 g of the epoxy resin obtained in Example-1.
- 1 g of methylimidazole, 1 g of calcium stearate and 370 g of silica powder were added and kneaded at 100°C for 5 minutes using two rolls. After cooling, the mixture was pulverized to obtain a molding material. This molding material was molded for 10 minutes at a pressure of 30 Kg/cm ^-1 using a hot press at 160°C. The performance of the molded product thus obtained is shown in Table 2. Reference Example 2 55 g of phenol novolak resin and 2-phenyl-4 were added to 100 g of the epoxy resin obtained in Example-2.
- A molded product was obtained in the same manner as in Reference Example 1 by adding 1 g of methylimidazole, 1 g of calcium stearate, and 360 g of silica powder. The results of measurements of the thus obtained molded product in the same manner as in Reference Example 1 are shown in Table-
Shown in 2. Comparative example 1 Sumi-epoxy resin ESA-011 (bisphenol A type epoxy resin, epoxy equivalent 480g/eq
Sumitomo Chemical Co., Ltd. product) 23g of phenol novolak resin per 100g, 2-
A molded product was obtained in the same manner as in Reference Example 1 by adding 1 g of phenyl-4-methylimidazole, 1 g of calcium stearate, and 290 g of silica powder. The performance of this product was measured in the same manner as in Reference Example 1, and the results are shown in Table 2. As shown in Table 2, the epoxy resin according to the present invention has excellent heat resistance, water resistance, moisture resistance, and electrical properties, and has been found to be an extremely effective epoxy resin as an industrial material.

【table】

Claims (1)

[Claims] 1. The following formula (In the formula, n represents a number from 0 to 3.) An epoxy resin represented by: 2 2,2'-dihydroxybiphenyl formaldehyde resin obtained by reacting 2,2'-dihydroxybiphenyl and formaldehyde in the presence of an acid catalyst and 1-halo-2,3-epoxypropane in the presence of an alkali. A method for producing an epoxy resin characterized by reacting with.