JPS63273626A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain the titled composition, having excellent operability and productivity without precipitating and solidifying an inorganic filler during transportation and storage, by adding an anionic surfactant and silane based coupling agent to an epoxy resin containing the inorganic filler. CONSTITUTION:The aimed composition obtained by adding (B) an anionic surfactant (e.g. sodium polyoxyethylene lauryl ether sulfate) and (C) a silane coupling agent (e.g. gamma-glycidoxypropyltrimethoxysilane) to (A) an epoxy resin containing an inorganic filler, such as silica powder, alumina, talc or calcium carbonate. Furthermore, the amounts of the blended components based on 100pts.wt. epoxy resin are preferably 5-700pts.wt. inorganic filler, 0.05-1pt.wt. component (B) and 0.01-1pt.wt. component (C).

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to an epoxy resin composition containing an inorganic filler.

(Prior art) Epoxy resin compounds containing inorganic fillers such as silica powder, alumina, talc, and calcium carbonate alone or in combination with two or more are particularly useful for applications such as casting, molding, impregnation, adhesives, paints, and civil engineering. Used in modified epoxy resin products, etc.

The problem with epoxy resins mixed with these inorganic fillers is that the inorganic fillers tend to settle or solidify during transportation or storage at high temperatures.As a countermeasure to this problem, ultrafine quartz powder ( There is a method of kneading a thixotropic agent such as (trade name: Aerosil) or bentone with an inorganic filler.

(Problems to be Solved by the Invention) However, the above-mentioned method of mixing quartz etc. has the problem that the viscosity of the epoxy resin composition increases due to the addition of quartz etc., resulting in poor workability and productivity. be.

Therefore, in epoxy resin compositions containing inorganic fillers, there is a need for a method of preventing solidification of the inorganic fillers without adding quartz, bentone, etc. that increase viscosity. To achieve this, the epoxy resin itself has a surfactant effect by adding a surfactant, and the wettability of the mixed inorganic filler with the epoxy resin is modified, thereby improving the dispersion of the inorganic filler. One possible method is to improve the properties of the inorganic filler and prevent it from solidifying. However, when a surfactant is added, the defoaming properties are significantly deteriorated, and the resulting cured molded product has an increased number of bubbles, making it brittle, so it has not been put to practical use.

Therefore, an object of the present invention is to provide an epoxy resin composition in which the solidification of the inorganic filler is prevented by adding a surfactant, but the defoaming property is not deteriorated.

(Means for solving the problem) When a surfactant is added to the epoxy resin, it is possible to solve the problem of solidification of the inorganic filler. But that's all
Epoxy resin compounds mixed with inorganic fillers have defoaming and
The defoaming property is extremely poor and the physical properties of the cured product are poor, making it unusable. Therefore, in addition to the above formulation, the present inventors
Furthermore, by adding a silane coupling agent,
It was discovered that defoaming and antifoaming properties could be improved, and the problem of solidification of inorganic fillers could be solved, and as a result of extensive research into the blending ratio, etc., the present invention was completed.

That is, the epoxy resin composition of the present invention is made by adding an anionic surfactant and a silane coupling agent to an epoxy resin containing an inorganic filler.

Preferably, the epoxy resin composition of the present invention contains 100 parts by weight of epoxy resin, 5 to 700 parts by weight of an inorganic filler,
Anionic surfactant 0.01 to 5.0 parts by weight, particularly preferably 0.05 to 1.00 parts by weight, silane coupling agent 0.001 to 1O60 parts by weight, particularly preferably 0
．． 01 to 1.00 parts by weight are added.

The amount of anionic surfactant depends on the amount of inorganic filler, but if it is less than 0.01 parts by weight based on 100 parts by weight of the epoxy resin, it will not be effective, and if it is more than 5.00 parts by weight, it will not be effective for defoaming. The amount of the silane coupling agent was determined to be in the range of 0.01 to 5.00 parts by weight because the effect of the silane coupling agent was not as great. Furthermore, if it is less than 0.05 parts by weight, the solidification state of the inorganic filler is slightly improved, but no practical effect is obtained. In addition, in the range of 1.00 to 5.00 parts by weight, a sufficient surfactant effect can be obtained, but the defoaming and antifoaming properties deteriorate, so the effect of the silane coupling agent becomes
Since a large amount of silane coupling agent is required to obtain the effect, it lowers the glass transition temperature of the cured product and increases the price of the composition, making it unsuitable for practical use.
A range of 1.00 parts by weight is particularly preferred.

The amount of the silane coupling agent varies depending on the amount of the anionic surfactant, but if it is less than 0.001 parts by weight based on 100 parts by weight of the epoxy resin, it will not be effective;
If the amount is more than 0.001 to 10.0 parts by weight, the amount added is too large and the glass transition temperature becomes low. In addition, if the amount is less than 0.01 part by weight, some improvement can be seen in the defoaming and antifoaming properties, but the actual degassing process takes time and workability deteriorates. Defoamability and antifoaming properties can be sufficiently improved within the range of 1.5 parts, but due to the large amount added, the glass transition temperature of the cured product decreases and the heat resistance decreases, and the price of the composition increases. It is not practical, therefore, a range of 0.01 parts by weight to 1.00 parts by weight is particularly preferred.

Any type of epoxy resin may be used, but
Liquid epoxy resins such as bisphenol A type, bisphenol F type, bisphenol A type F type, and alicyclic type are preferred.

Surfactants include cationic, nonionic, block copolymer, or anionic surfactants, and cationic, nonionic, or block copolymer surfactants include silane coupling agents. In the present invention, an anionic surfactant is used because the defoaming property cannot be improved by adding a silane coupling agent. .

As the anionic surfactant, sodium polyoxyethylene lauryl ether sulfate, polyoxyethylene lauryl ether triethanolamine sulfate, sodium polyoxyethylene alkyl ether sulfate, sodium alkyl sulfate, triethanolamine alkyl sulfate, and the like can be used.

Examples of silane coupling agents include T-glycidoxyprobyltrimethoxysilane, β-(3,4-
Epoxycyclohexyl)ethyltrimethoxysilane and the like can be used.

(Function) In the epoxy resin composition of the present invention, since a surfactant is added, the dispersibility of the inorganic filler is increased, and solidification and sedimentation are prevented.

Furthermore, since it contains a silane coupling agent, deterioration in defoaming properties caused by surfactants is eliminated.

Therefore, the inorganic filler is difficult to solidify and settle, and the resin has good defoaming properties, and when used as an epoxy resin for casting or molding, high-quality cured molded products can be produced.

(Examples) Hereinafter, the present invention will be described in further detail based on Examples.

Example 1: 100 parts by weight of bisphenol A liquid epoxy resin having an epoxy equivalent of 189 (Araldite GY 260 manufactured by CI BA-GE IGY), 0.10 parts by weight of polyoxyethylene lauryl ether sulfate triethanolamine
A resin composition was obtained by blending the heavy wall portion, 0.02 parts by weight of γ-glycidoxypropyltrimethoxysilane, and 50 parts by weight of crystalline silica powder (trade name 311. Nagase Sangyo).

Example 2: Hisphenol F type liquid epoxy resin (manufactured by DIC Corporation t!
piclon 830-3) 100 parts by weight, polyoxyethylene lauryl ether sulfate triethanolamine 0.10 parts by weight, T-glycidoxyprobyltrimethoxysilane 0.02 parts by weight, and 50 parts by weight of the above silica powder. A resin composition was obtained.

Comparative Example 1: Bisphenol A liquid epoxy resin (CIBA-GE
A resin composition was obtained by blending 100 parts by weight of Araldite GY260 (manufactured by IGY) and 50 parts by weight of silica powder.

Comparative Example 2: Hisphenol F type liquid epoxy resin (DIC E
piclon 830-S) and 50 parts by weight of the above silica powder were blended to obtain a resin composition.

Test Example 1: Put 300 g of each of the epoxy resin compositions of Example 1, Example 2, Comparative Example 1, and Comparative Example 2 into a 300 alt mayonnaise bottle, and test between Takarazuka and Tokyo (approximately 1000 hours, 1 round trip for 3 to 4 days). ) was transported back and forth by truck three times (12 days), and the solidification state thereafter was examined to conduct a transportation test. The results are shown in Table 1.

In the table, O1Δ, × represent the following solidification state.

○... Insert the rod and push it with your finger until it reaches the bottom.

Δ... Insert the rod and push with enough force to reach the bottom.

×...The rod doesn't bite at all.

The epoxy resin compositions of Examples 1 and 2 were epoxy resin compositions according to the present invention, and could be easily stirred without solidifying even if the silica precipitated. Also, Comparative Examples 1 and 2
The epoxy resin compositions of Examples 1 and 2 do not contain an anionic surfactant and a silane coupling agent, but both were solidified.

Test Example 2: Each of the epoxy resin compositions of Example 1, Example 2, Comparative Example 1, and Comparative Example 2 was placed in a test tube (30φ x 200 m).
The test tube was placed vertically in a hot air circulation oven and subjected to heat aging tests at 80°C for 724 hours and at 120°C for 8 hours. It is divided into three layers: clear layer A, layer B with dispersed filler, and layer 0 with excess filler. Height of each layer A layer: amm, B layer = baII
1, 0 layer: cam) was measured, and the degree of sedimentation was calculated according to the following formula. The larger the sedimentation degree value, the better the filler is dispersed in the resin and indicates that it is not solidified.

C In addition, the solidification state was evaluated according to the same criteria as Test Example 1. The results are shown in Table 2.

From Table 2, the epoxy resin compositions of Examples 1 and 2 can be easily re-stirred without solidifying even if silica precipitates during the heat aging test, and the epoxy resin compositions of Comparative Examples can be easily stirred. It is clear that the sedimentation and solidification of the inorganic filler is more significant than in the epoxy resin compositions of Examples, both from the degree of absorption and from the solidification state.

Test Example 3 An epoxy resin composition having the same composition as in Example 1 above was treated in the same manner as in Test Example 2 above, except that it did not contain a silane coupling agent and the amount of anionic surfactant was different. A heat aging test was conducted at 80°C/24h.

The amount of anionic surfactant and test results for each epoxy resin composition are shown in Table 3 below.

3i 1) Polyoxyethylene lauryl ether sulfate triethanolamine 2) Defoaming property ○: Shows normal defoaming property and defoaming property. (Standard) Pa Δ: It takes longer to defoam and defoam than O, but defoaming will occur if the pressure is reduced over time.

×: Even when the pressure is reduced, the defoaming and defoaming properties take longer than O, and the defoaming does not occur completely.

XX: Degassing takes longer than ×, and defoaming does not occur even if the pressure is reduced over time.

×××: In terms of defoaming and defoaming properties, defoaming does not occur even if the pressure is reduced for a longer time than ××.

As is clear from the table, when a silane coupling agent is not added and an anionic surfactant is added, defoaming properties deteriorate. The antifoaming properties become worse as the amount of the anionic surfactant increases, and when the amount exceeds 0.50 parts by weight, no antifoaming is achieved.

Note that the degree of sedimentation is good in all cases.

Test Example 4 Regarding epoxy resin compositions having the same composition as in Example 1 above, except that the amount of the silane coupling agent was different,
A heat aging test was conducted at 80° C./24 hours in the same manner as in Test Example 2 above. The amount of silane coupling agent and test results for each epoxy resin composition are shown in Table 4 below.

From Table 4, it is clear that an amount of the silane coupling agent of 0.015 parts by weight or more is effective. In addition, the degree of sedimentation is good regardless of the amount of silane coupling agent, but the degree of sedimentation is low when it does not contain a surfactant and only contains a silane coupling agent.
It is clear that it is in a solidified state.

Test Example 5: Using a cationic surfactant, a nonionic surfactant, or a block copolymer surfactant instead of an anionic surfactant, and whether or not a silane coupling agent is added or the amount added is Regarding epoxy resin compositions having the same composition as Example 1 except that they are different.

Defoamability, sedimentation degree and solidification state were tested. Each test was conducted according to the methods of Test Examples 1 to 3, respectively. (However, the sedimentation degree was determined only for 8Q'C/2/.) The results are shown in Table 5 below.

Table 5 From this test, it is clear that when a cationic surfactant or a nonionic surfactant is used as a surfactant, the defoaming property is poor and the solidification state is not improved. It should be noted that tests conducted separately have revealed that even if a silane coupling agent is added to these surfactants, the defoaming properties are not improved regardless of the amount. Furthermore, with respect to the block copolymer surfactant, it is clear from this test that although the solidification state and the degree of sedimentation are improved, the defoaming property is not improved even if a silane coupling agent is added.

(Effects of the Invention) In the epoxy resin composition of the present invention, the inorganic filler hardly precipitates or solidifies during transportation or heat storage (
In addition, even if it precipitates or solidifies, it can be easily stirred again.

Moreover, the viscosity of the epoxy resin composition does not increase, and the defoaming property does not increase and the cured molded product does not become brittle. Therefore, when used as a casting or molding resin, high quality cured molded products can be obtained with good workability and productivity.

Claims (1)

[Claims] An epoxy resin composition prepared by adding an anionic surfactant and a silane coupling agent to an epoxy resin containing an inorganic filler.