JP2003082065A - Organic-inorganic hybrid epoxy resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic-inorganic hybrid epoxy resin composition having excellent heat-resistance by using an aromatic amine as a curing agent and suppressing the lowering of the elastic modulus at a high temperature above the glass transition temperature. SOLUTION: The epoxy resin composition contains an epoxy resin, a m- xylylenediamine, an alkaline aqueous solution and an epoxysilane expressed by general formula (1) (R1 is CH3 or C2 H5 ) as essential components. The addition amount of the epoxysilane is set to attain an SiO2 content of 10-20 wt.% calculated by the equation (1): SiO2 content = [(60/Mw×χ)×100]/(total weight of varnish excluding solvent) (Mw is the molecular weight of the epoxysilane; and χ is the addition amount of the epoxysilane).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an organic-inorganic hybrid epoxy resin composition having excellent heat resistance.

[0002]

2. Description of the Related Art Electronic components used in electrical and electronic equipment, communication equipment, calculators, computers, etc.
With the weight reduction, the epoxy resin composition used as one of the constituent materials of electronic parts is required to have higher reliability such as higher elastic modulus and lower linear expansion coefficient. There is.

Epoxy resins have hitherto been well balanced in terms of heat resistance, adhesiveness, electrical characteristics, mechanical strength, moldability and cost, and are widely used. However, it has been considered difficult to maintain the mechanical strength of a cured epoxy resin product at a high temperature portion exceeding Tg because it causes a rapid decrease in elastic modulus at the glass transition temperature Tg. . As a method of compensating for this drawback, a large amount of an inorganic filler is blended to increase the elastic modulus of the cured product, the functional group number of the epoxy resin is increased to increase the crosslink density, or a bulky substituent is introduced into the epoxy resin to obtain a cured product. A method has been taken such as three-dimensionally controlling the structure of (1) to increase the temperature at which it migrates to the rubber-like region as much as possible, but in any case, the fundamental solution has not been reached.

On the other hand, for the purpose of improving the defects of the cured epoxy resin, a method of chemically bonding an alkoxysilane to a system of bisphenol A type epoxy resin and tetraethylenepentamine (hereinafter abbreviated as TEPA) by using a sol-gel reaction. Has been reported so far. Ochi et al. Of Kansai Univ. Used Polymer Frontier 21 (2000) to add bisphenol A type epoxy resin to TEPA and γ-glycidoxypropyltrimethoxysilane (hereinafter abbreviated as γ-GPS).
By the so-called In-Situ method, in which Tg disappears, Tg disappears in the dynamic viscoelasticity measurement, and a cured product with almost no decrease in elastic modulus can be obtained. However, when the curing agent is aromatic amines or In the case of an acid anhydride system, it is reported that the above-mentioned cured product cannot be obtained. Generally, TEPA-containing aliphatic amines have a drawback that the reaction with an epoxy resin is initiated even at room temperature, thus impairing storage stability and limiting the range of application.

Also, in the 9th Polymer Materials Forum Forum Abstracts (2000), Arakawa Chemical's Goda et al.
A silane-modified epoxy resin obtained by chemically bonding a methoxysilane oligomer is mixed with an equivalent amount of a curing agent and cured, so that Tg disappears in the dynamic viscoelasticity measurement and there is almost no decrease in elastic modulus. They report that they can get things. In addition, Japanese Unexamined Patent Application Publication No. 2000-
No. 281756, JP-A-2000-281965, JP-A-2000-290350 and the like are also reported. In these cases, since the secondary hydroxyl group of the epoxy resin is an essential component, it has a drawback that it cannot be applied to an epoxy resin having no secondary hydroxyl group.

[0006]

In view of such circumstances, an object of the present invention is to provide an organic-inorganic hybrid type epoxy resin composition which suppresses a decrease in elastic modulus in a high temperature portion exceeding Tg and is excellent in heat resistance. To provide.

[0007]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned problems, the present inventors have found that the curing agent is metaxylylene diene in the same manner as in the previously reported Japanese Patent Application No. 2001-091433. Amine (hereinafter abbreviated as MXDA)
In the case of, the alkaline aqueous solution was added together, and the epoxysilane obtained by the formula (1) had a SiO ₂ content of 10 w.
It has been found that the addition within the range of t% or more and 20 wt% or less is effective. In the present invention, the same effect was not obtained when water or an acidic aqueous solution other than the alkaline aqueous solution was added together. Therefore, in the case of aromatic amines, it is essential to add an aqueous solution having a hydrogen ion concentration (hereinafter abbreviated as pH) in a range showing alkalinity, and under these conditions, a cured product can be obtained even in a high temperature portion exceeding Tg. The inventors have found that it is possible to obtain a cured product that suppresses a decrease in elastic modulus and has excellent heat resistance, and has completed the present invention.

That is, the present invention is an organic-inorganic hybrid type epoxy resin composition characterized by containing an epoxy resin, metaxylylenediamine, an alkaline aqueous solution, and an epoxysilane represented by the general formula (1) as essential components. Is.

[0009]

[Chemical 2] In the formula, R ₁ represents CH ₃ or a C ₂ H ₅ group.

Furthermore, the addition amount of epoxysilane is set to 1 when the SiO ₂ content calculated by the formula (1) is 1.
It is characterized in that it is set to be in the range of 0 wt% or more and 20 wt% or less.

[0011]

[Equation 2] In the formula, Mw: molecular weight of epoxysilane, χ: amount of epoxysilane added

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Examples of the epoxy resin used in the present invention include bisphenol A type epoxy resin, alkyl-substituted bisphenol A type epoxy resin, halogen-substituted bisphenol A type epoxy resin, bisphenol F type epoxy resin, and alkyl substituted type. Type bisphenol F
Type epoxy resin, halogen-substituted bisphenol F type epoxy resin, bisphenol S type epoxy resin, glycidyl amine type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin,
Examples include cyclopentadiene type epoxy resin.

The amount of metaxylylenediamine used in the present invention is not particularly limited, but is preferably 0.1 to 0.5, and more preferably 0.1 in terms of the equivalent amount to the epoxy resin.
Good values between 5 and 0.3. If it is less than 0.1 in terms of equivalent ratio, there is a possibility that curing failure may occur due to lack of a curing agent and the expected characteristics may not be obtained, which is not preferable. Also,
If the equivalent ratio is 0.5 or more, unreacted MX after curing
There is a possibility that DA will remain and the reliability will be greatly impaired, which is not preferable.

The type of the alkaline aqueous solution used in the present invention is not particularly limited, but for example, an aqueous ammonia solution,
An aqueous solution of sodium hydroxide, an aqueous solution of potassium hydroxide, or the like, and when the concentration is 5 to 20%, the addition amount is 0.1 with respect to 100 parts by weight of the added epoxysilane.
-5 parts by weight is preferred. It is more preferably 0.5 to 3 parts by weight. If the amount is less than 0.1 part by weight, the hydrolysis reaction of the alkoxysilane in the epoxysilane is not promoted, which is not preferable. On the other hand, when the amount is more than 5 parts by weight, the hydrolysis reaction of the alkoxysilane in the epoxysilane is excessively promoted and the simultaneous reaction with the epoxy group (In-
The Situ polymerization method) may be impaired, or excess alkaline aqueous solution may remain in the cured product, resulting in a decrease in reliability, which is not preferable.

The epoxysilane used in the present invention is
The (OR ₁ ) 3 group in the general formula (1) is a trimethoxy group or a triethoxy group. The amount of epoxy silane added is
In the SiO ₂ content obtained by the formula (1),
It is preferable to add within the range of 10 wt% or more and 20 wt% or less. If it is less than 10 wt%, it may not be possible to expect the effect of suppressing the decrease in elastic modulus of the cured product in the high temperature portion exceeding Tg. On the other hand, when 20 wt% or more is added, the surface hardness of the cured product becomes strong, but other than that, it becomes brittle and the desired mechanical strength may not be obtained, which is not preferable.

The organic-inorganic hybrid type epoxy resin composition of the present invention contains a curing accelerator, if necessary, in addition to the above.
A solvent, an inorganic filler, etc. can be added.

The type and amount of the curing accelerator used in the present invention are not particularly limited. For example, the types include trisdimethylaminomethylphenol (TAP), imidazole derivatives, triphenylphosphine (TPP), D
BU salt etc. are mentioned. The amount of addition is preferably 0.1 to 5 parts by weight, more preferably 0.5 to 3 parts by weight, based on 100 parts by weight of the epoxy resin. If the addition amount is less than 0.1 part by weight, there is a possibility that the desired effect of hardening promotion cannot be obtained. On the other hand, when the amount is more than 5 parts by weight, the pot life becomes too short, storage stability may be impaired, and workability may be deteriorated.

For the purpose of adjusting viscosity or uniformly dispersing and mixing, one kind of solvent may be used, or two or more kinds of solvents may be used in combination, if necessary. The type of solvent is not particularly limited, but for example, N, N-dimethylformamide, 1,4-
Polar solvents such as dioxane and dimethylsulfoxide, n
-Hydrocarbon solvents such as hexane and cyclohexane, ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone, ester solvents such as butyl acetate and benzyl acetate, methyl cellosolve, butyl cellosolve, methyl carbitol, ethyl carbitol and methyl cellosolve. Examples thereof include polyhydric alcohols such as acetate, ethylene glycol and diethylene glycol, and their derivatives.

Further, an inorganic filler may be combined for the purpose of adjusting viscosity or imparting thixotropy. The type of the inorganic filler is not particularly limited, for example, carbonates and sulfates of various metals, alumina, amorphous silica or spherical silica, titanium oxide, potassium titanate,
Talc etc. are mentioned, and these can be used together by 1 type (s) or 2 or more types. The addition amount of the inorganic filler is not particularly limited as long as the composition in the present invention is in a liquid state and does not impair the fluidity.

The organic-inorganic hybrid epoxy resin composition of the present invention is preferably used after mixing the above components and thoroughly kneading with a stirrer or the like.

[0021]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The temperature change of the elastic modulus was measured for the characteristic evaluation. The measuring method was as follows, and the measurement results are shown collectively in FIG. In the following, “part” means “part by weight”.

[Evaluation Method of Elastic Modulus] The resin compositions prepared in each of the examples and comparative examples were 0.5 mm in thickness and 1 per side.
The resin composition was poured into a chrome-plated metal mold having a square shape of 0 cm and heat-cured in a hot-air circulation dryer at 90 ° C. × 2 hours + 120 ° C. × 2 hours + 150 ° C. × 2 hours to obtain a resin composition. A cured product was obtained. After returning this to room temperature, it was cut into a size of width: 5 mm, length: 30 mm, and a dynamic viscoelasticity measuring device (Rheovibron manufactured by Orientec Co., tension method, frequency: 100 Mz, measurement temperature range:
The change in elastic modulus was investigated using -150 ° C to 260 ° C and a temperature rising rate of 2 ° C / min).

(Example 1) Bisphenol A type epoxy resin (Dow Chemical Japan, DER # 331J) 1
00 parts and 85 parts of γ-GPS (Toray Dow Corning Silicone, SH-6040) were placed in a beaker and stirred and mixed with a magnetic stirrer for 10 minutes, and then 10
% Aqueous potassium hydroxide solution (hereinafter referred to as KOHaq) was slowly added dropwise with a dropper. Then, the mixture was stirred and mixed for 4 hours until the added water drops of KOHaq disappeared completely. After defoaming with a vacuum dryer, it is returned to the magnetic stirrer again, 30 parts of MXDA (manufactured by Wako Pure Chemical Industries, Ltd.) is dropped with a dropper, and the mixture is stirred for 30 minutes to obtain SiO ₂
A resin composition having a content of 10 wt% was obtained.

(Example 2) In Example 1, γ-GP
A resin composition having a SiO ₂ content of 14 wt% was obtained in the same manner as in Example 1 except that the amount of S was 176 parts and the amount of MXDA was 50 parts.

(Comparative Example 1) Bisphenol A type epoxy resin (made by Dow Chemical Japan, DER # 331J) 1
Take 00 parts in a beaker, add 18 parts of MXDA (manufactured by Wako Pure Chemical Industries) with a dropper while stirring with a magnetic stirrer, and stir for 30 minutes to obtain a SiO ₂ content of 14 w.
t% of the resin composition was obtained.

(Comparative Example 2) In Example 1, KOHa
A resin composition having a SiO2 content of 10 wt% was obtained in the same manner as in Example 1, except that 1 part of water was used instead of 1 part of q.

(Comparative Example 3) In Example 2, KOHa
A resin composition having a SiO ₂ content of 14 wt% was obtained in the same manner as in Example 2, except that 1 part of water was used instead of 1 part of q.

As is clear from the elastic modulus evaluation results summarized in FIG. 1, the organic-inorganic hybrid epoxy resin composition of the example according to the present invention is a comparative example 1 in which γ-GPS (epoxysilane) and KOHaq are not used in combination. Or KOH
It can be seen that the elastic modulus is less decreased at high temperature as compared with Comparative Examples 2 to 3 in which water is used instead of aq.

[0029]

EFFECT OF THE INVENTION The organic-inorganic hybrid epoxy resin composition of the present invention is obtained by adding an alkaline aqueous solution together, even when an aromatic amine type curing agent is used, to obtain a cured product at a high temperature of Tg or higher. The decrease in elastic modulus in the region can be greatly reduced, and excellent heat resistance is exhibited.

[Brief description of drawings]

FIG. 1 is a diagram showing changes in elastic modulus obtained by dynamic viscoelasticity evaluation in Examples and Comparative Examples.

Continued front page    F term (reference) 4J036 AA01 AD01 AD04 AD05 AD08                       AD20 AF06 AF15 AH00 DA01                       DA02 DA04 DC04 DC10 DC41                       DC46 FA02 FA05 FA06 FA11                       FA13 GA29 KA04

Claims (2)

[Claims] 1. An organic-inorganic hybrid epoxy resin composition comprising an epoxy resin, metaxylylenediamine, an alkaline aqueous solution, and an epoxysilane represented by the general formula (1) as essential components. [Chemical 1] In the formula, R ₁ represents CH ₃ or a C ₂ H ₅ group. 2. The amount of epoxysilane added is calculated by the formula (1).
The SiO ₂ content calculated by is 10 wt% or more and 20 w
characterized in that it is set to be in a range of t% or less,
The organic-inorganic hybrid epoxy resin composition according to claim 1. [Equation 1] In the formula, Mw: molecular weight of epoxysilane, χ: amount of epoxysilane added