JP2506601B2 - Liquid epoxy resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-viscosity liquid epoxy resin composition which gives a cured product having excellent heat resistance.

[0002]

2. Description of the Related Art Various liquid epoxy resin compositions containing a maleimide compound are known as epoxy resin compositions which give cured products having excellent heat resistance. For example, Japanese Patent Application Laid-Open No. 64-79216 discloses a liquid epoxy resin composition comprising a maleimide compound, an epoxy resin, an acid anhydride and an organic peroxide. In this known technique, in order to prevent the maleimide compound from precipitating as crystals, the maleimide compound and the epoxy compound are preliminarily heated and reacted at a temperature of 120 to 140 ° C. in the presence of a peroxide, and then the reaction product is obtained. An acid anhydride is added to and mixed with the mixture to prepare a composition. Therefore, in the case of this composition, it is difficult to obtain a composition having a uniform composition because the heating reaction accompanies the preparation of the composition, and since the obtained composition is a one-liquid type, it has a long life. After a lapse of time, the viscosity increased, and the storability was still unsatisfactory. Also,
This composition had a high viscosity and was not yet satisfactory in terms of workability.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid epoxy resin composition containing a maleimide compound, which has a low viscosity and is excellent in storability.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention. That is, according to the present invention, an epoxy resin and 2
A first liquid comprising a mixture of a polymerizable unsaturated compound having a viscosity of 100 cps or less at 5 ° C., a curing accelerator for an epoxy resin, an organic peroxide having a decomposition temperature of 60 hours or more with a half-life of 10 hours, and maleimide. A liquid epoxy resin composition comprising a second liquid composed of a carboxylic acid anhydride having a compound dissolved therein is provided.

The epoxy resin used in the present invention includes bisphenol A glycidyl ether and bisphenol F.
Examples include glycidyl ether, bisphenol S glycidyl ether, phenol novolac glycidyl ether, cresol novolac glycidyl ether, triphenylmethane glycidyl ether, and cycloaliphatic epoxy. It does not matter whether the epoxy resin is liquid or solid at room temperature.

The polymerizable unsaturated compound has a temperature of 25 ° C.
The viscosity of 100 cps or less is used.
Examples of such substances include hydroxyethyl acrylate, hydroxypropyl acrylate, isobornyl acrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, trimethylol. Acrylic esters such as propane triacrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, isobornyl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, neopentyl glycol dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate. , 1,6-
There are methacrylic acid esters such as hexanediol dimethacrylate, allyl compounds such as diallyl phthalate monomers, and styrene monomers. This polymerizable unsaturated compound can be used alone or in the form of a mixture.
This compound has the effects of dissolving the epoxy resin and greatly reducing the viscosity of the composition. In addition, this compound also exhibits an effect of imparting high heat resistance to a cured product by a copolymerization reaction with a maleimide compound in the presence of an organic peroxide in the curing reaction of the composition.

Examples of the carboxylic acid anhydride used in the present invention include those which are liquid at room temperature, such as methylated tetrahydrophthalic anhydride, methylated hexahydrophthalic anhydride, methylhymic acid anhydride and methylnadic acid anhydride. .

As the maleimide compound used in the present invention, various conventionally known compounds are used, and various compounds such as monomaleimide, dimaleimide, polymaleimide and the like are included, and the use of dimaleimide is particularly preferable. Examples of such a material include those shown below.

N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, N-butylmaleimide, N-hexylmaleimide, N-octylmaleimide, N-dodecylmaleimide, N-phenylmaleimide, Np-toluylmaleimide, N-m-toluylmaleimide, N-o-toluylmaleimide, Np-xylylmaleimide, Nm-xylylmaleimide, N-o
-Monomaleimide compounds such as xylylmaleimide, N-α-naphthylmaleimide, N-benzylmaleimide, N, N '-(methylenedi-p-phenylene) dimaleimide, N, N'-m-phenylenedimaleimide, N,
N'-p-phenylenedimaleimide, N, N'-2,4
-Tolylene dimaleimide, N, N'-2,6-tolylene dimaleimide, N, N'-m-xylylene dimaleimide, N, N'-p-xylylene dimaleimide, N, N '
-Oxydipropylene dimaleimide, ethylenedioxybis-N-propylmaleimide, oxybis-N-ethylmaleimide, N, N'-ethylenedimaleimide, N,
Dimaleimide compounds such as N'-trimethylenedimaleimide, N, N'-tetramethylenedimaleimide, N, N'-hexamethylenedimaleimide, N, N'-dodecamethylenedimaleimide; poly (phenylmethylene) polymaleimide compounds Such as polymaleimide compounds.

In the curing reaction of the composition, the maleimide compound is copolymerized with the polymerizable unsaturated compound by the action of the organic peroxide to give a heat resistant resin having a high crosslinking density. As the curing accelerator for epoxy resin, any one can be used as long as it does not substantially react with the epoxy compound at room temperature. Such curing accelerators are conventionally known ones, for example, triphenylphosphine, tin octylate, dicyandiamide, boron trichloride / tertiary amine complex salt, boron trifluoride / amine complex salt, imidazole and tertiary amine. Examples include fine powdery substances in which a nitrogen-containing compound such as is modified to form an inactive film on the surface thereof.

As the organic peroxide, one having a decomposition temperature of 60 hours or more with a half-life of 10 hours is used. Examples of such a material include octanoyl peroxide,
Decanoyl peroxide, lauroyl peroxide, cumyl peroxide octoate, acetyl peroxide, benzoyl peroxide, 1,1-bis (tert-butylperoxy) 3,3,5-trimethylcyclohexane, 1,1-bis ( Tert-butylperoxy) cyclohexane, tert-butylperoxylaurate, cyclohexanone peroxide,
1,1-ditertiary butyl peroxy-3,3,5
-Trimethylcyclohexane, 2,5-dimethyl-2,
5-dibenzoylperoxyhexane, tert-butylperoxyacetate, 2,2-bister butylperoxybutane, tert-butylperoxybenzoate, dicumyl peroxide, 2,5-dimethyl-2,5-ditertiary Examples thereof include butyl peroxyhexane, tertiary butyl cumyl peroxide, ditertiary butyl peroxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide and tertiary butyl hydroperoxide. The use of an organic peroxide having a decomposition temperature of less than 60 ° C. with a half-life of 10 hours deteriorates the storage stability of the first liquid constituting the composition of the present invention.

The polymerizable unsaturated compound used in the present invention is used in a proportion of 10 to 200 parts by weight, preferably 30 to 150 parts by weight, based on 100 parts by weight of the epoxy resin. When the amount of this compound used is less than 10 parts by weight, the effect of lowering the viscosity of the composition is small, and when it is more than 200 parts by weight, the curing shrinkage becomes large in the curing reaction of the composition, and the dimensional accuracy of the cured product deteriorates. , Cracks will occur. The carboxylic acid anhydride is 0.5 to 1.5 equivalents, preferably 0.7 to 1.3 equivalents, per epoxy equivalent of the epoxy resin.
Used in equivalent proportions. The maleimide compound is used in a proportion of 5 to 50% by weight, preferably 10 to 40% by weight, based on the total amount of the epoxy resin, the polymerizable unsaturated compound and the carboxylic acid anhydride. If the amount used of this product is less than 5 parts by weight, the heat resistance of the cured product becomes insufficient, and 50% by weight
The higher the amount, the higher the viscosity of the composition. The proportion of the curing accelerator for the epoxy resin used is not particularly limited, but is generally 0.01 to 5 parts by weight, preferably 0.1 to 3 parts by weight, relative to 100 parts by weight of the epoxy resin. The amount of the organic peroxide used is not particularly limited, but generally with respect to the total amount of the polymerizable unsaturated compound and the maleimide compound,
It is 0.01 to 5% by weight, preferably 0.02 to 3% by weight.

The composition of the present invention comprises a first liquid formed by uniformly mixing, among the above components, an epoxy resin, a polymerizable unsaturated compound, a curing accelerator for an epoxy resin and an organic peroxide, and a carboxylic acid. It is composed of a second liquid formed by heating and dissolving a maleimide compound in an anhydride. Such first
When the composition is a two-liquid composition consisting of the liquid and the second liquid, the first liquid and the second liquid have very excellent storage stability. In addition, the first liquid and the second liquid are mixed at the time of use to form a one-liquid composition. Such a composition has a very low viscosity and has a viscosity of 25 ° C. 1 to 50 poise and low viscosity of 24 to 12
It is held for a relatively long time of 0 hours. Therefore, this composition is very excellent in workability.

In the first and / or second liquid of the present invention, a conventional auxiliary additive component, for example, a filler such as silica-alumina, aluminum hydroxide, mica, wollastonite, or the like,
An appropriate amount of pigment, dye, silane coupling agent, and defoaming agent can be added.

[0015]

INDUSTRIAL APPLICABILITY The liquid epoxy resin composition comprising the first liquid and the second liquid of the present invention is very excellent in storage stability, and the liquids of the first liquid and the second liquid are excellent. The mixture has a very low viscosity and has the advantage of excellent workability. The cured product of the composition of the present invention has excellent heat resistance. The epoxy resin composition of the present invention is advantageously used as a sealing material for electric / electronic parts, a coating material, a coil impregnating material, and the like.

[0016]

Next, the present invention will be described in more detail with reference to examples. The number of parts shown below is based on weight.

Examples 1 to 8 The first liquid component and the second liquid component shown in Table 1 were mixed, and the mixture was subjected to viscosity (initial viscosity) at 25 ° C. immediately after mixing, linear shrinkage, and curing. Glass transition temperature and 10%
The weight loss temperature was measured as follows, respectively.
Table 1 shows the results. (Initial viscosity) Measured with a rotational viscometer (Linear shrinkage rate) An inner diameter of 90 mm was cast into a metal cylindrical container to a depth of 5 mm, heated at 100 ° C for 3 hours, and further heated at 170 ° C for 5 hours to cure, It was calculated from the diameter of the cured product and the inner diameter of the container. (Glass transition temperature) 5 cut out from the cured product obtained in measuring the linear shrinkage ratio
It was measured by thermomechanical analysis using a sample of × 5 × 20 (mm). (10% weight loss temperature) Using a sample of about 10 mg cut out from the cured product obtained in the measurement of the linear shrinkage, it was measured by thermogravimetric analysis.

The specific contents or properties of the compounding ingredients shown in Table 1 are as follows. (1) Epicoat 154 Phenol Novolac Glycidyl Ether (Oilized Ciel Epoxy) (2) Epicoat 828 Bisphenol A Diglycidyl Ether (Oilized Ciel Epoxy) (3) Neopentylglycol Dimethacrylate 25 ° C. Viscosity: 5 cps ( 4) Glycidyl methacrylate 25 ° C. viscosity: 4 cps (5) Maleimide I Diphenylmethane bismaleimide (6) Maleimide II Tetrafunctional maleimide, trade name “MP-2000X” (manufactured by Mitsubishi Petrochemical Co., Ltd.) (7) Peroxide I 1, 1-dibutylperoxy-3,5,5-trimethylcyclohexane (decomposition temperature with half-life of 10 hours: 95 ° C)

[0019]

[Table 1]

Comparative Examples 1 to 7 Example 1 was prepared by mixing the first liquid component and the second liquid component shown in Table 2.
The performance of the mixture was evaluated in the same manner as in. The results are shown in Table 2. The 2-hydroxy-3-phenoxypropyl acrylate shown in Table 2 has a viscosity at 25 ° C. of 170 cps.

[0021]

[Table 2]

Example 9 and Comparative Examples 8 to 14 The components shown in Table 3 were prepared, the first and second liquids shown in Table 2 were prepared from these components, and their performances were evaluated as follows. It was Table 3 shows the results. The peroxide II shown in Table 3 is tertiary butyl pervivarate, and its decomposition temperature with a half-life of 10 hours is as low as 55 ° C. Further, A shown in the table indicates that it is the first liquid component, and B indicates that it is the second liquid component. (First liquid initial viscosity) Viscosity of mixed liquid immediately after mixing first liquid component A (Second liquid initial viscosity) Viscosity of mixed liquid immediately after mixing second liquid component B (first liquid thickening ratio) Ratio of viscosity at 25 ° C. to initial viscosity after the first liquid was stored in an atmosphere of 40 ° C. for 30 days (thickening ratio of second liquid) 25 after the second liquid was stored in an atmosphere of 40 ° C. for 30 days Ratio of viscosity at ° C to initial viscosity

[0023]

[Table 3]

[0024]

[Table 4]

Front page continuation (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location C08L 63/00 NLB C08L 63/00 NLB

Claims (1)

(57) [Claims] 1. An epoxy resin and a viscosity of 100 at 25 ° C.
A first liquid composed of a mixture of a polymerizable unsaturated compound having a cps or less, a curing accelerator for an epoxy resin, an organic peroxide having a half-life of 10 hours and a decomposition temperature of 60 ° C. or more, and a maleimide compound were dissolved. A liquid epoxy resin composition comprising a second liquid composed of a carboxylic acid anhydride.