JPS6069125A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:The titled composition which is lowly viscous, easily handleable, excellent in the moisture resistance of a cured product, and suitable as an insulating material or the like, obtained by using 1,1-bis(4-hydroxyphenyl)ethane diglycidyl ether as an epoxy resin component. CONSTITUTION:1,1-bis(4-hydroxyphenyl)ethane diglycidyl ether is used as an epoxy resin component and, if desired, other epoxy resins (e.g., bisphenol A- derived epoxy resin) are added. This epoxy resin component is mixed with a curing agent component (e.g., phthalic anhydride or diethylenetriamine) to obtain the purpose epoxy resin composition. 1,1-bis(4-hydroxyphenyl)ethane diglycidyl ether is prepared from epichlorohydrin and 1,1-bis(4-hydroxyphenyl)ethane obtained by reacting acetaldehyde with phenol.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an epoxy resin composition, and its purpose is to obtain an epoxy resin composition that has a cured product with excellent moisture resistance.A second purpose is to obtain an epoxy resin composition that has a low viscosity and is easy to handle. The object of the present invention is to easily obtain an epoxy resin composition.

Epoxy resins have excellent mechanical strength, adhesive strength with various base materials, electrical properties, and chemical resistance, so they are widely used in various fields such as structural materials, adhesives, and electrical insulation materials. ing.

Epoxy resins include diglycidyl ether of bisphenol, glycidyl ether of polyhydric alcohol, and glycidyl ester of polyhydric carboxylic acid.

Glycidyl ether of novolak type phenols.

There are epoxidized products of olefins, but from the viewpoint of ease of handling and balance of properties of the cured product.

Among these, especially bisphenol type epoxy resin
The diglycidyl ether of a2-bis(4-hydroxyphenyl)propane (hereinafter referred to as bisphenol Am epoxy resin) and the diglycidyl ether of bis(4-hydroxyphenyl)methane (hereinafter referred to as bisphenol F type epoxy resin) are the prizes. has been done.

However, in recent years, particularly in the fields of electrical and electronic industries, a higher level of reliability has been required for various parts, and with this, higher levels of reliability have also been required for the epoxy resin compositions used in various parts. Moisture resistance is now required.

On the other hand, from the viewpoint of workability or the viewpoint of high thermal conductivity which can be achieved by incorporating a large amount of inorganic filler, epoxy resins with lower viscosity are being sought.

Against this background, the present inventors have studied the types of epoxy resins in particular in order to obtain an epoxy resin composition with low viscosity and excellent moisture resistance of the cured product.
The present inventors have discovered that diglycidyl ether of 1-bis(4-hydroxyphenyl)ethane exhibits excellent moisture resistance, and have completed the present invention.

That is, the present invention relates to an epoxy resin composition containing diglycidyl ether of 1,1-bis(4-hydroxyphenyl)ethane.

Diglycidyl nitrate of 1,1-bis(4-hydroxyphenyl)ethane used in the present invention.

It is synthesized by a conventional method from 1,1-bis(4-hydroxyphenyl) compound 17 obtained by reacting acetaldehyde and phenol and epichlorohydrin, and is coated with, for example, Mitsui Petrochemical Epoxy 1. This epoxy resin has a feature of lower viscosity than bisphenol A epoxy resin and bisphenol F epoxy resin, which have been praised in the field.

Generally, in order to lower the viscosity of a bisphenol-type epoxy resin represented by the following formula, (1) increase the number of molecules represented by fl == Q in the formula 1 by adjusting the reaction ratio of bisphenols and epichlorohydrin. or (2) dilution using a reactive diluent. However, method (1) has the drawback that the yield during synthesis is reduced, resulting in an increase in cost, and that the resin becomes more likely to crystallize, that is, solidify, as the number of molecules with n=0 increases.

Here, R1, &: H or alkyl group n: 0 or a positive integer This tendency is particularly remarkable in the case of bisphenol F type epoxy resin, and high purity products are crystalline even at room temperature.

Furthermore, method (2) is very effective in lowering the viscosity.

Diluents are generally unfavorable from the viewpoint of safety due to their skin irritation and high vapor pressure, and they also have the disadvantage of deteriorating the mechanical properties, heat resistance, electrical properties, moisture resistance, etc. of the cured product.・However, the diglycidyl ether of 1,1-bis(4-hydroxyphenyl)ethane used in the present invention has an extremely low viscosity and is characterized by hardly crystallizing even at low temperatures. This molecular structure is bisphenol All
This is presumed to be because it has an asymmetric molecular structure, unlike bisphenol F-type epoxy resins. .

On the other hand, in order to improve the moisture resistance of cured epoxy resin products, conventionally the focus has been on the type of curing agent and the type and amount of auxiliary materials such as fillers. The relationship between this and moisture resistance was not clear. Recently.

The present inventors have studied the molecular structure of bisphenol-type epoxy resins in order to improve the moisture resistance of hard pentoxides of bisphenol-type epoxy resins.

1,1-bis(4-hydroxy7enyl) as described above
It was discovered that diglycidyl ether of ethane is superior to expectations.

It is considered that the moisture resistance of a cured epoxy resin is better when the molecular structures are similar, and the higher the crosslinking density of the cured product is, that is, the lower the epoxy equivalent of the epoxy resin used. From this point of view, bisphenol F type epoxy resin is considered to exhibit the best moisture resistance, but in reality, bisphenol F type epoxy resin is a diuretic of 1,1-bis(4-hydroxyphenyl)ethane used in the present invention. Inferior to glycidyl ether. The reason for this is that in the case of bisphenol 1 liter epoxy resin, crystallization is prevented; u61.
In addition to 1-bis(4-hydroxyphenyl)methane, 1.
1-His(2-hydroxyphenyl)methane is used in combination, and this 1.1-bis(2-hydroxyphenyl)
It is presumed that methane lowers the moisture resistance.

61 In the present invention, as an epoxy resin component.

In addition to the diglycidyl ether of 1.1-bis(4-hydroxyphenyl)ethane, other epoxy resins and reactive diluents can be used as long as the properties are not deteriorated.

Examples of these are bisphenol A epoxy resins,
Bisphenol F type epoxy resin, polyglycidyl ether of polyhydric alcohol, polyglycidyl ester of polybasic acid, 3,4-epoxycyclohexylmethyl (3,4
- Cycloaliphatic epoxy resins such as epoxycyclohexane) carboxylate and vinylcyclohexene oxide.

Examples include glycidyl ethers of alcohols such as phenyl glycidyl ether and butyl chrycidyl ether, and glycidyl esters of carboxylic acids such as t-butylbenzoic acid.

In the epoxy resin composition of the present invention, any conventionally known curing agent can be used.

For example, acid anhydrides such as phthalic anhydride, methyl, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, dodecenylsuccinic anhydride, diethylenetriamine, triethylenetetramine, diaminodiphenylmethane, metaphenylenediamine.

Amines and their derivatives such as benzyldimethylamine, tris(dimethylamitsumethyl)phenol, dicyandiamide, dicarboxylic acid dihydrazide, 2-ethyl-
These include imidazoles such as 4-methylimidazole. Furthermore, an acid anhydride may be used as a curing agent, and tertiary amines or imidazoles may be used in combination as an accelerator.

In the present invention, various fillers may be used as necessary.

Flame retardants 9, colorants, etc. may also be used.

The present invention will be explained below with reference to Examples. Parts indicate parts by weight.

Example 1 Diglycidyl ether of 1.1-bis(4-hydroxyphenyl)ethane (Ebomic R manufactured by Mitsui Oil Epoxy ■)
-710) 100 parts, 86 parts of methyltetrahydrophthalic anhydride (Hitachi Chemical ■1IljHN-2200) and 2-ethyl-4-methylimidazole 1 as an accelerator.
Mix the parts uniformly and defoam.

Pour into a 2-hole thick mold and heat at 80°C for 3 hours at 9 then 120°C.
It was cured at ℃ for 8 hours to obtain a resin plate.

Comparative Example 1 A resin plate was obtained in the same manner as in Example 1, except that bisphenol A type epoxy resin (Epicoat 828 manufactured by Yuka Shell ■) 10 (1, 80 parts of methyltetrahydrophthalic anhydride) was used.

Comparative Example 2 A resin plate was obtained in the same manner as in Example 1, except that 100 parts of bisphenol F type epoxy resin (Epicoat 807 manufactured by Yuka Shell ■) and 88 parts of methyltetrahydrophthalic anhydride were used.

A moisture resistance test was conducted using the resin plate obtained in the above example using the first method.

Moisture resistance test A: A 50 x 50 test piece was cut out from a resin plate and immersed in boiling water for 4 hours and then in cold water at 23°C for 16 hours, and then the weight of the resin plate was measured.

The water absorption rate was calculated from the difference in weight before and after the test.

Moisture resistance test B: Using a resin plate cut out to 60 x 60 mm, the same treatment as in moisture resistance test A was performed, and the relative permittivity and dielectric loss tangent of the resin plate before and after test 9 were measured at a frequency of 10K H.
Measured at z.

Humidity test C: Using the same test piece as in moisture resistance test A.

It was exposed to superheated steam at 121°C and 2 atm for 8 hours. The water absorption rate was calculated from the weight before and after the test.

The results of these tests are shown in Table 1.

Table 1 Example 2 Example 1. Regarding the bisphenol type epoxy resin used in Comparative Examples 1 and 2, the type of bisphenol, the viscosity of the epoxy resin obtained from it, and Example 1. Comparative example 1.2
The relationship between the viscosity of the epoxy resin composition 10 shown in Table 1 was evaluated. The results are shown in Table 2.

Example 3 100 parts of diglycidyl ether of 1.1-bis(4-hydroxyphenyl)ethane and 40 parts of modified diaminodiphenylmethane (Hitachi Kayaku Kayahard As) were uniformly mixed, defoamed, and poured into a mold with a thickness of 20 mm. The resin plate was then cured at 80°C for 3 hours and then at 100°C for 4 hours.

Comparative Example 3 Bisphenol A type epoxy resin (Epico) 82
A 11-resin plate was obtained in the same manner as in Example 3 except that Example 8 was used.

Comparative Example 4 A resin plate was obtained in the same manner as in Example 3 using 92 parts of Epikote 828, 8 parts of butyl glycidyl ether, and 50 parts of modified diaminodiphenylmethane.

Example 3. Moisture resistance test A was conducted on the resin plates obtained in Comparative Example 3 and Comparative Example 4. The water absorption rate was 0.32% for the composition of Example 3, 0.45% for the composition of Comparative Example 3, and 0.52% for the composition of Comparative Example 4.

As mentioned above, 1,1-bis(4-hydroxyphenyl)
An epoxy resin composition using diglycidyl ether of ethane has a lower viscosity of liquid resin than other bisphenol type epoxy resins, and the cured product has excellent moisture resistance. Hence electricity.

In addition to being suitable for insulation treatments such as impregnation and casting of electronic components, it is also expected to improve moisture resistance in fields such as structural materials such as FRP and paints.

Claims (1)

[Claims] An epoxy resin composition containing diglycidyl ether of 1, 1.1-bis(4-hydroxyphenyl)ethane.