CH674208A5 - - Google Patents

Description

DESCRIPTION

The present invention relates to an epoxy resin composition containing an inorganic filler, an anionic surfactant and a silane coupling agent.

Epoxy resin compositions in which one or more inorganic fillers, e.g. Quartz powder, aluminum oxide, talc, calcium carbonate or the like can be incorporated, especially in the fields of casting and molding compounds and synthetic resin impregnation as well as modified epoxy resin compositions, such as e.g. used as an adhesive or coating material and as such for use in construction technology and in the construction sector. These epoxy resin compositions containing inorganic fillers have the disadvantage that the inorganic filler tends to deposit or solidify during transport or during storage at elevated temperature.

As a measure against this phenomenon, the combined use of thixotropic agents such as e.g. very finely ground quartz powder (commercially available under the trade name Aerosil), bentonite and the like, are known.

However, this addition of fine quartz powder and the like is disadvantageous in that this addition increases the viscosity of the epoxy resin composition, thereby lowering processability and labor productivity.

Accordingly, with regard to epoxy resin compositions containing inorganic fillers, a way is being sought to solidify the inorganic filler without adding viscosity-increasing material, e.g. To prevent quartz powder, bentonite and the like.

One possibility is the addition of a surfactant which imparts a surface-active effect to the epoxy resin, which improves the wettability of the inorganic filler by the epoxy resin and thereby the dispersibility of the inorganic filler and thus prevents its solidification. However, the foam-destroying and foam-preventing properties of the composition are significantly impaired by the addition of the surfactant. A product hardened from such a molding compound therefore has an increased foam content and is therefore fragile. 5 This is why this method is not used in practice.

The object of the present invention is to find an epoxy resin composition in which the solidification of the inorganic filler is prevented by adding a surfactant, but without reducing the foam-destroying properties of the resin.

DE-A 2 652 045 discloses the use of cationic surfactants and silane couplers in the consolidation of loose underground sand formations in boreholes using curable organic resins. Furthermore, EP-A 57,595 describes a process for the scratch and abrasion-resistant coating of glass containers with resin mixtures, which among other things. Contain surfactants and silane coupling agents. EP-A 20 83.053 describes nonionic surfactants and silane coupling agents as constituents for aqueous primer compositions for glass fibers. A similar process using only cationic surfactants is known from JP-A Sho 51-35 799. Furthermore, US-A 25 4 522 966 describes non-tarnishing, abrasion-resistant coatings for transparent polycarbonate moldings, which among other things. contain an epoxy-containing silane coupling agent and a nonionic surfactant in an acrylate polymer composition.

It has now surprisingly been found that the foam-destroying and foam-preventing properties can be improved and, in addition, the solidification of the inorganic filler can be prevented if a silane coupling agent is added to an epoxy resin composition containing a surfactant. 35 The present invention relates to an epoxy resin composition containing an inorganic filler and an anionic surfactant and a silane coupling agent.

The epoxy resin composition according to the invention expediently contains 5-700 parts by weight of the inorganic filler, 0.01-5.0 parts by weight, in particular 0.05-1.0 parts by weight, of the anionic surfactant and 0.001-10, 0 parts by weight, in particular 0.01-1.0 parts by weight of the silane coupling agent based on 100 parts by weight of the epoxy resin.

The amount of anionic surfactant can also depend on the amount of inorganic filler. However, if the amount of the anionic surfactant is less than 0.01 part by weight based on 100 parts by weight of the epoxy resin, this has no effect. If the amount of the anionic surfactant is greater than 5.0 parts by weight, the foam-disturbing property of the composition is largely reduced, so that the silane coupling agent does not show its preventive effect. Therefore, the appropriate amount of the anionic surfactant is 0.01-5.0 parts by weight. If the amount of the anionic surfactant is less than 0.05 55 parts by weight, this has no practical effect, although the solidification of the inorganic filler is prevented to a small degree. If the amount of the anionic surfactant is 1.0-5.0 parts by weight, the foam-destroying and foam-preventing properties are so greatly reduced that the silane coupling agent does not show its effect or the silane coupling agent is used in a large amount to have an effect, which lowers the glass transition temperature of the cured product and raises the cost of the resin composition 65 to an impractical level. Therefore, the preferred amount of the anionic surfactant is 0.05-1.0 parts by weight.

The amount of silane coupling agent used can be from

674 208

depend on the amount of anionic surfactant. However, if the amount of the silane coupling agent is less than 0.001 part by weight based on 100 parts by weight of the epoxy resin, this has no effect. If the amount used exceeds 10.0 parts by weight, this large amount of the silane coupling agent lowers the glass transition temperature (Tg value).

Therefore, the silane coupling agent should suitably be used in an amount of 0.001-10.0 parts by weight of lenlauryl ether sulfate, sodium polyoxyethylene alkyl ether sulfate, sodium alkyl sulfate, triethanolamine alkyl sulfate, which are particularly preferred.

Silane coupling agents include epoxyorganosilanes, amino-organosilanes, carboxyorganosilanes, mercaptoorganosilanes, methacryloxyorganosilanes, chloroorganosilanes, vinylorganosilanes and cyanoorganosilanes.

Particularly suitable silane coupling agents are the epoxy organosilanes, e.g.

will. If the amount of the silane coupling agent is less than 10 parts by weight of glycidoxymethyltrimethoxysilane than 0.01 part by weight, the foam-destroying process takes too much time and the processability is reduced, although a certain improvement in the foam-destroying and foam-preventing properties is achieved. If the amount of the silane coupling agent is 1.0-10.0 parts by weight, this large amount lowers the glass transition temperature and the heat resistance of the cured product and also increases the cost of the composition, so that the use of such a large amount of silane Adhesion promoter is no longer of practical importance. Therefore, the preferred amount of the silane coupling agent used is 0.01-1.0 parts by weight.

Suitable epoxy resins according to the present invention are all polyepoxides which have an average of two or more 1,2-epoxy groups in one molecule. These can be saturated, unsaturated, aliphatic, alicyclic, aromatic or heterocyclic epoxides. These can also be a non-obstructing substituent such as e.g. have a halogen atom, a hydroxyl group, an ether group, an ester group or the like. Examples of such polyepoxides are novolaks, polyglycidyl ethers of dihydric phenols such as e.g. 2,2-bis (4-hydroxyphenyl) propane, l, l-bis (4-hydroxyphenyl) ethane, bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) sulfone, Resorcinol or hydrochipon, polyglycidyl ether of trihydric alcohols such as e.g. Glycerin, polyglycidyl esters such as e.g. Diglycidyl phthalate or diglycidyl isophthalate, epoxidized esters of polyethylenically unsaturated fatty acids such as e.g. epoxidized linseed oil, epoxidized esters of unsaturated alcohols with unsaturated carboxylic acids such as 3,4-epoxy-cyclohexylmethyl-3,4-epoxicyclohexyl carboxylate; further epoxidized polyethylenically unsaturated hydrocarbons such as e.g. epoxidized 2,2-bis (2-cyclohexenyl) propane, epoxidized vinylcyclohexane, epoxidized cyclopentadiene dimer and the like.

Preferred epoxy resins are polyglycidyl ethers of polyhydric phenols and epoxide esters of unsaturated alcohols with unsaturated carboxylic acids.

Surfactants include cationic, nonionic and anionic surfactants, as well as those of the block copolymer type. With regard to the foam-forming properties of surfactants of the cationic nonionic or block copolymer type, these cannot be improved in the direction of foam-destroying properties, not even by adding a silane coupling agent, but only those of anionic surfactants are added by adding a silane coupling agent in the direction of foam destruction improved. Therefore, the present invention relates to the use of anionic surfactants.

Anionic surfactants include carboxylates, sulfonates such as e.g. Alkylbenzenesulfonates, alkylnaphthalenesulfonates, alkali sulfonates, α-olefin sulfonates, α-sulfofatty acid esters, sulfosuccinic acid esters; Alkoxy, acyloxy or acylaminoalkane sulfonates, sulfates such as e.g. Alkyl sulfates or ether sulfates, phosphonates or phosphates.

Anionic surfactants which are particularly suitable for use in accordance with the invention are ether sulfates, such as e.g. Sodium polyoxyethylene lauryl ether sulfate, triethanolamine polyoxyethyl

Glycidoxymethyltriethoxysilane beta-glycidoxyethyltrimethoxysilane beta-glycidoxyethyltriethoxysilane y-glycidoxypropyltrimethoxysilane 15 y-glycidoxypropyltriethoxysilane y-glycidoxypropyltri (methoxyethoxy) silane y-Glycidoxypropyltriacetoxysilan 8-Glycidoxybutyltrimethoxysilan 8-Glycidoxybutyltriethoxysilan 20 Glycidoxymethyldimethoxysilan

Glycidoxymethyl (methyl) dimethoxysilan Glycidoxymethyl (ethyl) dimethoxysilan Glycidoxymethyl (phenyl) dimethoxysilan GlycidoxymethyI (vinyl) dimethoxysilan 25 Glycidoxymethyl (dimethyl) methoxysiloxysiloxysiloxysiloxysiloxysiloxysiloxysiloxysiloxysilan (methyl) dimethoxysilane 30 y-glycidoxypropyl (ethyl) dimethoxysilane y-glycidoxypropyl (dimethyl) methoxysilane 5-glycidoxybutyl (methyl) dimethoxysilane ö-glycidoxybutyl (ethyl) dimethoxysilane glycidoxymethyl) diethoxysilane bis- (glycidoxyethyl) -dimethoxysilane bis- (glycidoxyethyl) diethoxysilane bis- (glycidoxypropyl) dimethoxysilane 40 bis- (glycidoxypropyl) diethoxysilane tris- (glycidoxymethyl) triloxysiloxysiloxysiloxysiloxysilane (methyl) glycidoxyethyl) ethoxysilane 45 tris (glycidoxypropyl) methoxysilane tris (glycidoxypropyl) ethoxysilane glycidylmethyl trimethoxy silane Glycidylmethyltriethoxysilan ß-Glycidylethyltrimethoxysilan 50 ß-Glycidylethyltriethoxysilan ß-glycidylpropyltrimethoxysilane y-y-Glycidylpropyltriethoxysilan Glycidylpropyltri (methoxyethoxy) silane y-Glycidylpropyltriacetoxysilan 55 3,4-Epoxycyclohexylmethyltrimethoxysilan Epoxycyclohexylmethyltriethoxysilan 3,4-3,4-epoxycyclohexylethyltrimethoxysilane, 3,4-3,4 Epoxycyclohexylpropyltrimethoxysilan Epoxycyclohexylbutyltrimethoxysilane. 60 Particularly preferred are y-glycidoxypropyltrimethoxysilane and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane.

Since the epoxy resin composition 65 according to the invention contains a surfactant, this brings about an improved dispersibility of the inorganic filler and prevents its solidification and sedimentation. Since the composition also contains a silane coupling agent, the

674 208

4th

overcome the deterioration of the foam-destroying properties from the surfactant content.

Thus, in the composition according to the invention there is no solidification or sedimentation of the inorganic filler, and this has excellent foam-destroying properties, so that when using such epoxy resin compositions as casting or molding compound, high-quality products are obtained.

Furthermore, the epoxy resin compositions may also contain additional components which are not important for the effect according to the invention, such as e.g. Dyes or stabilizers.

example 1

A resin composition is prepared by mixing 100 parts by weight of a liquid bisphenol A-based epoxy resin with an epoxide equivalent of 189 (Araldit® GY 260, Ciba-Geigy) with 0.1 part by weight of triethanolamine polyoxyethylene lauryl ether sulfate, 0.02 Parts by weight of y-glycidoxypropyltrimethoxysilane and 50 parts by weight of crystalline quartz powder (available under the trade name 3H, Na-gases & Co., Japan).

Example 2

A resin composition is prepared by mixing 100 parts by weight of a liquid bisphenol F-based epoxy resin (Epiclon® 830-S, DIC Co., Japan) with 0.1 part by weight of triethanolamine polyoxyethylene lauryl ether sulfate, 0.02 part by weight y-glycidyloxypropyltrimethoxysilane and 50 parts by weight of crystalline quartz powder (as in Example 1).

Comparative Example 1

A resin composition is prepared by mixing 100 parts by weight of a liquid bisphenol A-based epoxy resin (Araldit® GY 260, Ciba-Geigy) with 50 parts by weight of quartz powder (as in Example 1).

Comparative Example 2

A resin composition is prepared by mixing 100 parts by weight of a liquid bisphenol F-based epoxy resin (Epiclon® 830-S, DIC Co., Japan) with 50 parts by weight of quartz powder (as in Example 1).

Application example 1

Each 300 g of the epoxy resin compositions from Examples 1, 2, Comparative Examples 1 and 2 are filled into a 300 ml bottle. These are subjected to a road transport test in a truck for 12 days (approx. 6000 km). The degree of consolidation is then checked. The results are shown in Table 1.

Table 1

5 Example 1 Example 2 Comparative example 1 Example 2 Solidification O O X X

grad io In Table 1 and the following tables, the characters O, A and X denote the following degrees of solidification.

O: If a stick is pushed into the sample, it easily reaches the bottom of the sample at the touch of a finger.

A: If a rod is pushed into the sample, it only reaches the bottom of the sample under strong pressure.

X: The stick cannot be pressed into the sample at all.

In the epoxy resin compositions of Examples 1 and 2 according to the present invention, the quartz powder does not solidify and can be easily stirred even when sedimentation takes place.

In the epoxy resin compositions of Comparative Examples 1 and 2, the anionic surfactant and the silane coupling agent are fine, which leads to solidification of the quartz powder 25.

Application example 2 A sample bottle (30 cm 0 x 200 mm) is filled with epoxy resin compositions from Examples 1 and 2 and Comparative Examples 1 and 2 up to a height of 180 mm and in a vertical position in a hot air circulation oven at 80 C for 24 hours or subjected to a heat aging test at 120 C for 8 hours. In this test the contents of the sample bottle are separated into a clear layer A, a filler dispersion layer B and a layer C which contains excess filler. The heights of the layers are measured (layer A: a mm; layer B: b mm; layer C: c mm) and the degree of sedimentation is calculated according to the following equation. A higher degree of sedimentation means that the filler is more evenly dispersed in the resin and the degree of solidification is lower.

45 Degree of sedimentation

a + b + c x 100 [%]

In addition, the degree of solidification is determined according to application example 1.

50 The results are shown in Table 2.

Table 2

example 1

Example 2

Comparative

example 1

example 2

Sedimentation

80 ° C / 24 hours

33

36

27th

27th

Degree [%]

120 ° C / 8 hours

40

45

32

32

Degree of consolidation

O

O

X

X

The results of Table 2 show that the epoxy resin application example 3 compositions of examples 1 and 2 have no solidification. Epoxy resin compositions, according to example 1, of each quartz powder in the heat aging test; even without a silane coupling agent and with changing ge- if a certain sedimentation takes place, this can be made with anionic surfactant and the dimented quartz powder layer can be easily stirred. 65 heat aging test at 80 ° C./24 hours as in the application example shows the epoxy resin compositions subjected to piel 2.

Comparative Examples 1 and 2 significant sedimentation and the amounts of anionic surfactant used in each case marked solidification of the inorganic filler. and the results are shown in Table 3.

5

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Table 3

Formulation: Araldit® GY 260

100

100

100

100

100

100

100

[Parts by weight] surfactant 15

-

0.05

0.1

0.2

0.5

1.0

2.0

Quartz powder

50

50

50

50

50

50

50

Foam-destroying

O

X

X

X

XX

XXX

XXX

Properties21

Degree of sedimentation [%]

27th

32

33

31

29

27th

27th

io

1) Triethanolaminopolyoxyethylene lauryl ether sulfate

2) Foam-destroying properties:

O: normal, foam-destroying and foam-preventing properties (standard)

A: Foam disappears at reduced pressure for a long time; the time for foam destruction and foam prevention is greater than at 0.

X: Even at reduced pressure, the time until the foam disappears is longer than that at 0, and the foam cannot be completely destroyed. 20th

XX: Foam destruction takes even more time than with X and, despite reduced pressure, cannot be completely achieved for a long time.

XXX: Despite reduced pressure, there is no foam destruction for a longer period than with XX. 25 The results in Table 3 show that without the use of a silane coupling agent, the addition of an anionic surfactant deteriorates the foam-destroying properties of the composition. The foam-destroying properties deteriorate with an increasing amount of anionic surfactant and when the amount of surfactant rises above 0.5 part by weight, foam destruction is no longer achieved at all.

All compositions show good results with regard to the degree of sedimentation.

Application Example 4 Epoxy resin compositions, according to Example 1, but with a changing content of silane coupling agent, are prepared and subjected to the heat aging test at 80 ° C./24 hours analogously to Application Example 2.

The amounts of silane coupling agent used in each case and the results are shown in Table 4.

Table 4

Formulation: Araldit® GY 260

100

100

100

100

100

100

100

[Parts by weight] Tensid1 '

0.1

0.1

0.1

0.1

0.1

0.1

-

Quartz powder

50

50

50

50

50

50

50

Silane adhesive

0.002

0.006

0.015

0.02

0.05

0.1

0.02

medium3 '

Foam-destroying

A

A

A ~ 0

0

0

0

0

Properties2 '

Degree of sedimentation [%]

33

33

33

33

34

34

27th

1) + 2) See table 3

3) y-glycidoxypropyltrimethoxysilane

The results in Table 4 show that the effect of the silane coupling agent starts at an amount of 0.015 parts by weight45.

All compositions show good results with regard to the degree of sedimentation regardless of the amount of Si-lan adhesion promoter. Only the composition without surfactant but with silane coupling agent shows a low degree of sedimentation, which means that it is in a solid state.

50

Application Example 5 Epoxy resin compositions are prepared in accordance with Example 1, the anionic surfactant being replaced by cationic nonionic or block copolymer surfactants and the amounts of silane coupling agents being varied. The foam-destroying properties, the degree of sedimentation and the degree of solidification of these compositions are determined according to the methods described in Application Examples 1-3, the degree of sedimentation being determined only after heat aging at 80 ° C./24 hours. The results are shown in Table 5.

55

Table 5

Formulation:

Araldit® GY 260

100

100

100

100

100

100

[Parts by weight]

Surfactant katio

0.1

niche1 '

0.1

non-ionic2 '

0.1

0.1

0.1

0.1

Block copolymer3 '

Quartz powder

50

50

50

50

50

50

Silane adhesive

-

-

0.02

0.05

0.10

medium3 '

Foam-destroying properties5 '

X

X

X

X

X

X

Degree of sedimentation [%]

29

29

32

32

34

35

Degree of consolidation6 '

X

X

O

O

O

O

674 208

1) Cetyltrimethylammonium chloride, stearylbenzyldimethylammonium chloride and the like

2) polyoxyethylene nonylphenyl ether and the like

3) ethylene oxide-propylene oxide block copolymer

4) Y-glycidoxypropyltrimethoxysilane

5) See table 3

6) See table 1

The results of this application example show that the use of cationic or nonionic surfactants does not improve the foam-destroying properties and the degree of consolidation.

If a block copolymer surfactant is used, the foam-destroying properties are not improved, not even by adding a silane coupling agent. However, the degree of solidification and the degree of sedimentation are improved.

In the epoxy resin compositions according to the invention, hardly any deposition and solidification of the inorganic filler occur during transport or storage at elevated temperature. Even if it deposits 5 or solidifies, just stirring to dissolve it. Furthermore, there is neither an increase in the viscosity of the epoxy resin composition nor an increase in the tendency to foam, which renders hardened products made from it brittle.

10th

The epoxy resin compositions according to the invention therefore have good processability and good working productivity and, as casting and molding compositions, give high-quality hardened products.

C.

Claims (10)

674 208 2nd PATENT CLAIMS 1. Epoxy resin composition containing an inorganic filler, an anionic surfactant and a Si-lan adhesion promoter. 2. The composition according to claim 1, wherein the amount of the inorganic filler is 5-700 parts by weight based on 200 parts by weight of the epoxy resin. 3. The composition according to claim 1, wherein the amount of the anionic surfactant is 0.01-5.0 parts by weight based on 100 parts by weight of the epoxy resin. 4. The composition according to claim 3, wherein the amount of the anionic surfactant is 0.05-1.0 parts by weight. 5. The composition according to claim 1, wherein the amount of the silane coupling agent is 0.001-10.0 parts by weight based on 100 parts by weight of the epoxy resin. 6. The composition of claim 1, wherein the epoxy resin is a polyepoxide having an average of two or more 1,2-epoxy groups in the molecule. 7. The composition according to claim 1, wherein the anionic surfactant is a carboxylate, a sulfonate, a sulfate, a phosphonate or a phosphate. 8. The composition according to claim 8, wherein the anionic surfactant is an ether sulfate. 9. The composition according to claim 1, wherein the Si-lan coupling agent is an epoxy, amino, carboxy, mercapto, methacryloxy, chloro, vinyl or cyano-organosilane. 10. The composition according to claim 1, wherein the Si-lan coupling agent is an epoxyorganosilane.