JPS59152921A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain the titled composition giving a cured product having excellent flexibility, alkali resistance, water resistance and mar resistance, and useful for impregnation, casting, lamination and coating use, by compounding an epoxy resin, a diester dicarboxylic acid and a polycarboxylic acid anhydride. CONSTITUTION:The objective composition is prepared by compounding (A) an epoxy resin (e.g. polyglycidyl ether of polyphenol, etc.), (B) a diester dicarboxylic acid of formula [R1 and R3 are bivalent aromatic group or (cyclo)aliphatic group; R2 is H or methyl] and (C) a polycarboxylc acid anhydride (e.g. phthalic anhydride). The amounts of the components (B) and (C) are selected to be 0.15- 0.5 equivalent and 0.5-0.85 equivalent per 1 equivalent of the component (A), respectively. The component (B) is preferably prepared by reacting e.g. methyl hexahydrophthalic anhydride, etc. with triethylene glycol, etc. at a molar ratio of 2:1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an epoxy resin composition comprising an epoxy resin, a diester dicarboxylic acid, and a polycarboxylic anhydride.

In general, cured products made from epoxy resins and polycarboxylic anhydride curing agents have the disadvantage of poor resilience and brittleness against distortion. In order to improve this drawback, plasticization is usually carried out by adding polyglycols, but the alkali resistance and water resistance of the obtained cured product decrease. Also.

Japanese Patent Publication No. 55-43007 discloses a diester obtained by reacting an aromatic or cycloaliphatic dicarboxylic acid anhydride with an aliphatic or cycloaliphatic glycol (for example, tetrahydrophthalic anhydride and 1,6-hexanediol). It has been described that dicarboxylic acids can be used to impart flexibility, and a similar article was published in Japanese Patent Publication No. 33-609.
No. 7 describes the use of a high molecular weight polyalkylene ether dicarboxylic acid derived from maleic anhydride and a polyalkylene ether glycol having a polyalkylene ether group having at least about three consecutive alkylene ether groups. .

However, the cured coatings obtained by adding these compounds with terminal carboxyl groups are soft and have roughness, but are easily scratched.

Water resistance and alkali resistance are still unsatisfactory.

As described above, epoxy resin compositions imparted with flexibility, which are useful when used for impregnation, casting, and lamination, and are also useful when used for coating, have been used for coating. It had poor water resistance, alkali resistance and scratch resistance, which are required when used for commercial purposes.

The present invention solves these problems.

In other words, the present invention is as follows.

(Al　Epoxy tree 1 effect.

(B) General formula (1) )To-C-R1-C-α0CHCH20 sho C-R3-
In C-OHm (general formula), R1 and R3
represents an aromatic, aliphatic or cycloaliphatic divalent group, R2 represents a hydrogen group or a methyl group, and R1 and R3
may be the same or different, and three R2 may be the same or different) and (C) an epoxy resin composition containing a polycarboxylic acid anhydride.

As the epoxy resin (A) used in the present invention.

An epoxy resin having two or more epoxy groups in one molecule, such as polyglycidyl ether of polyphenol or polyalcohol.

Examples include polyglycidyl esters of polycarboxylic acids and polyepoxides obtained by epoxidizing double bonds with peracids.

The diester dicarboxylic acid represented by the general formula (I) is
It can be produced by reacting dicarboxylic acid with triethylene glycol or tripropylene glycol. Here, as dicarboxylic acid.

Phthalic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, hexahydrophthalic acid, methylhexahydrophthalic acid, 3,6-nindomethylenetetrahydrophthalic acid, methyl 3,6-nindomethylenetetrahydrophthalic acid, isophthalic acid, terephthalic acid , maleic acid, fumaric acid, co-phosphoric acid, adipic acid, azelaic acid, cepatic acid, dodecanedioic acid, etc. If the above dicarboxylic acid has an acid anhydride as a raw material, it is preferably used as an acid anhydride, and it is preferable to react 2 moles of dicarboxylic acid with 1 mole of triethylene glycol or tripropylene glycol while heating. preferable.

The polycarboxylic acid anhydride used in the present invention (C1 is the acid anhydride of the above dicarboxylic acid, dodecenyl succinic anhydride,
Examples include trimellitic anhydride and pyromellitic anhydride.

51 In the present invention, the formulation is such that diesterdicarboxylic acid (Bl'& preferably 0
．． 05-0.8 view, particularly preferably 0.15-0.5
The equivalent weight and polycarboxylic anhydride (C) are preferably 0
．． 2 to 0.95 mol, particularly preferably 0.5 to 0.85
made to become a mole. Diesterdicarboxylic acid (B
) If the amount used is too small, the removability will decrease and the cured product will tend to become brittle, and if it is too large, the heat resistance, water resistance, alkali resistance, etc. of the cured product will tend to decrease. Moreover, if the amount of polycarboxylic acid (C) used is too small, sufficient curing will not occur, and if it is too large, the properties of the cured product will tend to deteriorate.

The epoxy resin composition of the present invention contains benzyldimethylamine, tridimethylaminomethylphenol, and its octylate as a curing accelerator.

1.8-Diaza-bicyclo(5,4,0)undecene-
7. This formate, tertiary amine or its salt such as phenol salt, quaternary ammonium salt such as tetramethylammonium bromide, metal salt of organic acid such as tin 2-ethylhexanoate, acetyl 6-acetone nickel complex compound, etc. All organometallic complex compounds, etc., can be blended. curing accelerator.

It is used in an amount of 15% by weight or less based on the epoxy resin.

Further, the epoxy resin composition of the present invention may be further mixed with common modifiers such as fillers, plasticizers, organic solvents, dyes, pigments, flame retardants, etc. before curing.

Production Example 1 A mixture of 336ψ (2 moles) of methylhexahydrophthalic anhydride and 150P (1 mole) of triethylene glycol was heated at 120° C. for 9 hours with stirring under a nitrogen atmosphere. The product was a pale yellow solid with an acid number of 229 (theoretical value 230). The resulting compound is a diester dicarboxylic acid represented by 9 formula % formula %.

Production Example 2 A pale yellow solid compound with an acid value of 224 was obtained according to Production Example 2, except that tripropylene glycol was used instead of triethylene glycol.

This is the formula It is a diesterdicarboxylic acid represented by

Production Example 3 The reaction was carried out in the same manner as in Production Example 1 except that polyethylene glycol with an average molecular weight of 400 was used instead of triethylene glycol and maleic anhydride was used instead of hexahydrophthalic anhydride, so that both ends of polyethylene glycol were converted to maleic anhydride. A diester dicarboxylic acid esterified with an acid was obtained. This was a white solid with an acid value of 187.

Example 1 Epoxy resin (Acyldite GY250, Ciba Geigy Co., Ltd. trade name, epoxy resin 9185) 60X- parts,
Epoxy resin (Araldai) DYO22゜Ciba Geigy Co., Ltd. trade name, epoxy equivalent: 133) 40 parts by weight of diesterdicarboxylic acid obtained in Production Example 1, 30 parts by weight of methylhexahydrophthalic anhydride, and 1 part by weight of benzyldimethylamine Mix 130 parts by weight and apply on a glass plate.
C./30 minutes to obtain a colorless, transparent, flexible film with a thickness of 100 μm. The pencil hardness of this coating film was H.

In addition, in order to test the scratch resistance of the paint film, a 500 mm
After applying a load of 54 rpm and adjusting the tip of the polypropylene so that it was in contact with the coating film at a right angle, the coating film was rotated at 50 rpm. Even after spinning for 30 minutes, there were no scratches at all.

A cured film with a thickness of 100μ was placed in a 4% NaOH aqueous solution at 60°C.
When immersed in water for 5 hours and tested for alkali resistance, no matting or whitening was observed. Similarly, a water resistance test was conducted by immersing it in warm water at 80°C for 5 hours, but no fading or whitening was observed.

The heat deformation temperature of the cured product cured under the same conditions as for the creation of the coating film was 46°C, and the cured product with a 1" spring washer embedded was held at 1100°C for 30 minutes, then rapidly cooled to -10°C and subjected to thermal shock. No cracks occurred during the test, and good malleability was exhibited.

Example 2 The procedure of Example 1 was repeated except that the diester dicarboxylic acid obtained in Production Example 2 was used instead of the diester dicarboxylic acid obtained in Production Example 1. The scratch resistance, alkali resistance, and water resistance of the coating film were the same as those of Example 1.

The heat distortion temperature of the cured product was 45° C., and the crack resistance of the cured product was also similar.

Comparative Example 1 In Example 1, 2 moles of maleic anhydride and an average molecular weight of 40 were used instead of the diesterdicarboxylic acid obtained in Production Example 1.
Example 1 was carried out in the same manner as in Example 1 except that diester dicarboxylic acid obtained by reacting 1 mole of 0% polyethylene glycol was used.

=10- After curing at 130°C for 30 minutes, the coating film was pale yellow and flexible.
Pencil hardness was HB. When the same scratch resistance test as in Example 1 was conducted, scratches appeared in about 5 minutes. In both the alkali resistance test and the water resistance test, the paint film turned white. The heat distortion temperature of the cured product was 36° C., and no cracks were observed in the thermal shock test.

Comparative Example 2 The same procedure as in Example 1 was carried out using diesterdicarboxylic acid (pale yellow solid, acid value 244) obtained by reacting 2 moles of methylhexahydrophthalic anhydride with 1 mole of 1,6-hexanediol. . After curing for 30 minutes at 130'C, the coating film was clear, colorless, and flexible.

Pencil hardness was F. When the same scratch resistance test as in Example 1 was conducted, scratches appeared in about 20 minutes. Although the paint film had a slight orange peel in the alkali resistance test, no abnormalities were observed in the water resistance test.

The heat distortion temperature of the cured product was 50°C, and cracks were not frequently generated in the thermal shock test.

Comparative Example 3 The same procedure as in Example 1 was carried out except that 97 parts by weight of methylhexahydrophthalic anhydride was used instead of the mixture of tomethyl hexahydrophthalic anhydride diesterdicarboxylate as a curing agent.

The coating film after curing at 130° C. for 30 minutes was colorless and transparent but hard, with a pencil hardness of 2H. When the same scratch resistance test as in Example 1 was conducted, scratches occurred and the coating film cracked in about 10 minutes. No abnormalities were observed in the alkali resistance and water resistance tests. The thermal deformation temperature of the cured product was 83° C., and cracks occurred in the thermal shock test.

The epoxy resin composition according to the present invention, when cured, has excellent alkali resistance, water resistance, and scratch resistance as well as rounding properties, and is suitable for use in impregnation and casting.

Useful for lamination and coating.

141

Claims (1)

[Claims] 11A) Epoxy resin. (B) General formula (summer) (In the general formula (11), R1 and R3 represent an aromatic, aliphatic or cycloaliphatic divalent group, and R2
indicates hydrogen or methyl group. R1 and R3 may be the same or different, but three R2
may be the same or different); and fc) a polycarboxylic acid anhydride. 2, (for 1 equivalent of epoxy resin with Al component, (
B) component diester dicarboxylic acid 0. The epoxy resin composition according to claim 1, which contains Q5 to 0.8 equivalents and 0.2 to 0.95 moles of polycarboxylic anhydride.