JPS5817489B2 - Heat-resistant epoxy resin composition - Google Patents

Description

[Detailed description of the invention] The present invention relates to a novel heat-resistant epoxy resin composition.

More specifically, an imide ring-containing ester compound having the formula: (wherein R1 is an aromatic or aliphatic diamino residue, R2 is an aromatic or aliphatic dihydroxy residue) and two imide ring-containing ester compounds in one molecule. It is made by blending an imide epoxy resin obtained by reacting an epoxy compound having an epoxy group with an acid anhydride, and has excellent heat resistance as detailed below, and is mechanically and electrically resistant. The present invention relates to a heat-resistant engineered poxy resin composition that can provide a cured resin product with excellent properties.

A cured epoxy resin is produced by blending an epoxy compound with a curing agent such as an amine or an acid anhydride, and reacting the epoxy group in the epoxy resin with the curing agent.

Although such cured epoxy resin products are widely used in various fields due to their excellent electrical properties and dimensional stability, these epoxy compounds are not fully satisfactory in terms of heat resistance. .

For this reason, it is necessary to provide a heat-resistant epoxy resin cured product.A lot of research has been done in the past.

For example, in Japanese Patent Publication No. 49-12600, a cured epoxy resin with excellent heat resistance is obtained by blending an epoxy resin and a maleimide compound. Cracks are likely to occur due to cycles, and when used for impregnation or casting of large coils, for example, if heat cycles are applied after curing, the surface of the coil may peel off or crack, which poses a serious problem in practice.

In Zarani Special Publication No. 50-32119, etc.,
It has been shown that imide epoxy resin is produced by reacting an imide ring-containing dicarboxylic acid with an epoxy compound, and although such a cured imide epoxy resin certainly has excellent heat resistance, it It has problems such as difficulty in reacting with epoxy compounds.

The present inventors have developed a cured product that has heat resistance and excellent mechanical properties, is easily scalable, and is suitable for use in impregnation, casting, lamination, painting, etc. As a result of various studies to create an epoxy resin composition, it was found that an imide ring-containing ester compound (hereinafter referred to as an imido ester compound) having the formula: The inventors discovered that by blending an imide epoxy resin obtained by reacting an epoxy compound having an epoxy group with an acid anhydride, scales can impart heat resistance and flexibility to the resulting cured product, thus completing the present invention. It arrived.

That is, the heat-resistant epoxy resin composition of the present invention can be easily converted into an imide epoxy resin by using, instead of the imide ring-containing dicarboxylic acid, an imide ester compound which has a lower melting point and has excellent compatibility with the epoxy compound. In addition, the ester bond within the imide ester compound can impart flexibility to the cured product, and heat resistance can be imparted by reacting with the acid anhydride used as a curing agent. can.

By roughly changing the alcohol component of the imidoester compound, cured resin products with different properties can be obtained.

In general, derivatives with imide rings are poorly soluble, so it has traditionally been considered difficult to introduce imide rings into epoxy resins. It reacts easily in the presence of such substances and can scale imide epoxy resins.

The imidoester compound used in the present invention comprises 2 moles of trimellitic acid or trimellitic anhydride and the formula H2
1 mol of a primary diamine having the formula HO-R2-OH (wherein R1 is the same as above),
(wherein R2 is the same as above) can be easily mixed by mixing and reacting with heating.

Examples of primary diamines forming such imidoester compounds include 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, benzidine, j,3'-dichlorobenzidine, and 4. 4'-
Diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenyl ether, ■,
5-diaminonaphthalene, m-phenylenediamine, p
-phenylenediamine, m-xylylenediamine, p-
Examples include xylylene diamine, hexamethylene diamine, octamethylene diamine, decamethylene diamine, and hydrogenated 4,4'-diaminodiphenylmethane.

Rough formula HO-R2-OH (in the formula, R2 is the same as in the appendix)
Examples of diols having ethylene glycol, diethylene glycol, triethylene glycol, propylene gellicol, 1,3-propanediol, 1,
Examples include 4-butanediol, hexamethylene glycol, openentyl glycol, bisphenol A, hydroquinone, and hydrogenated bisphenol A.

It is preferable to select such diols as appropriate depending on the intended use of the cured resin material.

For example, to obtain a flexible cured resin, a linear glycol with a large number of carbon atoms is used, and to obtain a cured resin with a high heat distortion temperature, a rigid compound such as a hydrogenated compound of bisphenol is used. It is better to use compounds.

Further, as the epoxy compound used in the present invention, any epoxy compound having an epoxy equivalent of 5000 or less can be used, such as bisphenol A diglycidyl ether type Epicote 828°834.1001 or 1
Examples include, but are not limited to, 004 (manufactured by Shell Kagaku Co., Ltd.) and alicyclic type Chinsonox 221 or 289 (manufactured by Chisso Corporation).

It should be noted that an epoxy compound having an epoxy equivalent of 5,000 or more is not preferred because it has a high melting point and is difficult to react with, and the molecular weight of the imide epoxy resin produced becomes large, resulting in poor workability.

Furthermore, the epoxy curing agent used in the present invention has the formula: Examples include acid anhydrides.

The imide epoxy resin has 1.6 to 5 epoxy groups in the epoxy compound per equivalent of hydroxyl group in the imide ester compound.
It is mixed in a proportion of 0 equivalents and heated to about 0 at a temperature of 150 to 270°C without a catalyst or in the presence of an acid or base catalyst.
．． It can be obtained by reacting for 5 to 5 hours.

Next, the heat-resistant epoxy resin composition of the present invention can be changed by blending an acid anhydride into the imide epoxy resin at a ratio of 0.6 to 12 acid anhydrides per part of the epoxy end.

Here, the blending ratio of the epoxy compound was set to 1.6 to 50 equivalents per equivalent of the hydroxyl group of the imide ester compound, because if it is less than that, the molecular weight of the product will increase too much, and the compatibility of the curing agent etc. will be reduced. This is because the heat resistance of the cured product obtained is insufficient if the temperature is exceeded.

It is preferable to carry out the reaction without a solvent, or an appropriate amount of a polar solvent such as N-methylpyrrolidone or N,N-dimethylformamide may be used to further accelerate the reaction.

Furthermore, the blending ratio of the acid anhydride is set to 0.6 to 1.2 equivalents because if the amount is less than 0.6 equivalents, sufficient crosslinking will not occur and various properties will deteriorate, and if the amount is more than 12 equivalents, the crosslinking density will be too high. This is particularly because the mechanical properties deteriorate.

The imide epoxy resin may be used alone together with an acid anhydride, or may be used in combination with other epoxy compounds.

For example, by using it in combination with a novolac type epoxy compound having two or more epoxy groups in one molecule, a cured resin having a high heat distortion temperature can be obtained.

Next, the heat-resistant epoxy resin composition of the present invention will be explained with reference to Examples and Comparative Examples.

The structural formula and abbreviation of the imidonisdel compound used in each example are shown below.

Example 1 Imidoester compound represented by structural formula IE-1 31.
L9 (0.1 equivalent) and 380 g (2, CI amount) of Epicote 828, which is a bisphenol A diglycidyl ether type epoxy compound with an epoxy equivalent of 190, were mixed and reacted at 200° C. for 1 hour.

The product was a colored liquid and had an epoxy equivalent of 220 by the hydrochloric acid-dioxane method.

Furthermore, according to the infrared absorption spectrum, the characteristic absorption of the epoxy group around 910 cm-' decreased by 1 to 1780 cm-'.

Absorption characteristic of imide groups was observed in 1725c1rL-1 and 723CrfL-'', and it was confirmed that imide epoxy resin was produced.

150.0 g of methyltetrahydrofucric anhydride (0,
g equivalent) and heated at 150°C for 5 hours, then at 180°C.
A cured product was obtained by heating at C for 10 hours.

The bending strength of this product is 15.5 kg/ at 25°C.
mm, and the flexural modulus was 260 kg/mrtX.

Furthermore, when heated in air at 240° C. for 500 hours, the weight loss rate was 45%.

0~ in crack test using Oliphant washer method
'Withstands thermal shock of 200℃.

The value in the T-peel peel test was 10.0 psi (25°C
)Met.

Furthermore, the heat distortion temperature by TMA method was 100°C.

Example 2 Imidoester compound represented by structural formula IE-2 35.
9 g (0.1 equivalent) and 969 g (3.8 equivalent) of Epicote 834, which is a bisphenol A diglycidyl ether type epoxy compound with an epoxy equivalent of 255, were mixed, and CH30N al, Og was added as a catalyst to give 21.
Heated at 00C for 1 hour.

The product was a colored liquid and had an epoxy equivalent of 270 by the hydrochloric acid-dioxane method.

In addition, the infrared absorption spectrum shows that the characteristic absorption of epoxy groups near 910 cm-' decreases, and 1787 crrL-1,1
Imide group characteristic absorption was observed in 725crrL-' and 727CrrL-1, and formation of imide epoxy resin was confirmed.

To 271 (1 equivalent) of the obtained imide epoxy resin, 96.6 g (0.6
equivalent amount) and heated at 150°C for 15 hours to obtain a cured product.

The bending strength of this product was 16.0 kg/mm'' at 25°C, and the bending modulus was 330 kg/mm''.

Furthermore, the weight loss rate when heated in air at 240° C. for 500 hours was 7.2%.

The heat distortion temperature by TMA method was 150°C.

It withstood thermal shock from 0 to 200°C in one Olifant washer test.

Rough T beer peel test value is 12.5 psi (2
5°C).

Example 3 Imidoester compound represented by structural formula IE-3 50.
1 g (0.1 equivalent) and 95.0.9 (0.5 equivalent) of Epicote 828, a bisphenol A diglycidyl ether type epoxy compound with an epoxy equivalent of 190, were mixed and heated at 240 °C for 1 hour. did.

The product was a colored liquid with an epoxy equivalent weight of 350.

In addition, the infrared absorption spectrum shows that the epoxy characteristic absorption near 910cIrL-1 decreases, and 1782CrrL-'
, 1726crIl-' and 725CrrL-1 showed imide group characteristic absorption, and it was confirmed that imide epoxy resin was produced.

Methyl nadic acid anhydride 161 (0, g equivalent) was added to 351 (1 equivalent) of the obtained imide epoxy resin to make 15
The mixture was heated at 0°C for 5 hours and then at 180°C for 10 hours to obtain a cured product.

The bending strength of this product is 16.0 kg/ at 25°C.
mm, and the flexural modulus was 250 kvmm.

Furthermore, the weight loss rate when heated in air at 240° C. for 500 hours was 37%.

Furthermore, the heat deformation temperature was 115°C, and it withstood the thermal shock of O~2000G using the L1 Oliphant washer method.

One T-peel peel test showed a value of 12.0 psi (25°C).

Example 4 Imidoester compound represented by structural formula IE-4 30.
19 (0,1 equivalent) and 10 of Chissonox 289, which is an alicyclic type epoxy compound with an epoxy equivalent of 210.
5. (L9 (0.5 equivalents)) were mixed and heated at 230° C. for 1 hour.

The product was a colored liquid with an epoxy equivalent weight of 340.

According to the infrared absorption spectrum, the epoxy group special absorption around 910 crn-1 decreased, and 1780 crn-1,17
Absorption characteristic of imide groups was observed in 25CrfL-1 and 720CrIL-', and production of imide epoxy resin was confirmed.

DEN438, a novolak type epoxy compound, was added to 34CB9 (1 equivalent) of the obtained imide epoxy resin.
180 g (1 equivalent) and 199.2.9 (1.2 equivalents) of methyltetrahydrophthalic acid m-hydrate obtained by hardening and scraping were added and heated at 150° C. for 15 hours to obtain a cured product.

The bending strength of this product is 16.0 kg/ at 25°C.
mu, and the flexural modulus was 360 kg/mrrr''.

Moreover, when heated in air at 240°C for 500 hours, the weight loss rate was 80%°.

The thermal deformation temperature by the TMA method was 140°C, and it withstood the thermal shock of 0 to 200°C by the Oliphant washer method.

10.1 psi (rough T-peel peel test)
25°C).

Example 5 Imidoester compound represented by structural formula IE-5 31.
8 g (0.1 equivalent) and 33°2. ? (
0.18 equivalents) and added these to 300ml of N-methylpyrrolidone, and further added C3H1□ as a catalyst.
OK0.07.9 was added and heated at 2000C for 3 hours.

The epoxy equivalent weight of the product was 800.

As a result of infrared absorption spectrum analysis, 910CrrL-1
The characteristic absorption of the epoxy group in the vicinity decreases to 1782 (m-1
Absorption characteristic of imide groups was observed in 1726C1rL-1 and 725CTL-1, and it was confirmed that imide epoxy resin was produced.

139 g (01 g equivalent) of hexahydrofucric anhydride was added to 800 g (1 equivalent) of the obtained imide epoxy resin and heated at 150° C. for 5 hours and then at 200° C. for 5 hours to obtain a cured product.

The bending strength of this product is 14.5 kg at 25°C.
/ mm, and the flexural modulus is 245 kg/mm”
Met.

Moreover, the weight loss rate when heated in air at 240° C. for 500 hours was 5.0%.

The thermal deformation temperature by the TMA method was 130°C, and it withstood thermal shock of 0 to 200°C by the Oliphant washer method.

In rough T-peel peel test, 12.1psi (2
5°C).

Example 6 Imidoester compound represented by structural formula IE-6 49.
5. ! ? (0,1 equivalent) and 380 @(2
,0 equivalents) and heated at 240°C for 2 hours.

The product was a colored liquid with an epoxy equivalent weight of 230.

As a result of infrared absorption spectrum analysis, the formation of imide epoxy resin was confirmed.

Add 150 g (0 g equivalent) of methyltetrahydrofucric anhydride to 230 g (1 equivalent) of the selected imide epoxy resin.
was added and heated at 150°C for 15 hours and then at 180°C for 10 hours to obtain a cured product.

The bending strength of this product is 16.5 kg7 mm at 25°C.
2, and the flexural modulus was 300 kg/mnX.

Further, the thermal deformation temperature by the TMA method was 130°C, and it withstood thermal shock of 0 to 200°C by the Oliphant washer method.

In one T-peel peel test, 12.0psi (25°
C) values are shown.

Comparative Example 1 380 g of the above Epicote 828 with an epoxy equivalent weight of 190
(2,0 equivalents) to methyltetrahydrophthalic anhydride 3
08g (1.8 equivalents) was added and heated at 150°C for 15 hours.
The mixture was further heated at 180°C for 10 hours to obtain a cured product.

The bending strength of this product is 14.5 kg/m at 25°C.
m", and the flexural modulus was 340 ky/im2.

In addition, the heat distortion temperature by TMA method is 130°C, and 24°C.
When heated in air at 0° C. for 500 hours, the weight loss rate was 180%.

Furthermore, cracks were generated by thermal shock at 0 to 200°C using the Oliphant washer method.

In the T-peel peel test, 4.1 psi (25°C
) values are shown.

Claims (1)

[Claims] 1 Formula. (In the formula, R1 is an aromatic or aliphatic diamino residue, R2
is an aromatic or aliphatic dihydroxy residue) and an epoxy compound having two epoxy groups in one molecule. A heat-resistant epoxy resin composition.