JPH05295237A - Method for producing modified epoxy composition - Google Patents

Abstract

(57) [Summary] [Objective] A method for producing a modified epoxy composition capable of extremely efficiently producing a modified epoxy composition having high dispersibility of rubber-like particles and excellent properties including adhesiveness. To provide. In the method for producing a modified epoxy composition comprising a rubbery polymer [component (A)] dispersed in a compound having an epoxy group [component (B)] in a particulate form, a rubbery polymer latex is prepared. The particle size obtained by coagulating and crushing is 0.
A powder of component (A) having a size of 5 mm or less is blended with component (B) and uniformly dispersed.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a modified epoxy composition.

[0002]

2. Description of the Related Art In general, epoxy resins have dimensional stability,
It excels in many points such as mechanical strength, electrical insulation characteristics, heat resistance, water resistance, and chemical resistance. In particular, the epoxy resin that is preferably used as an adhesive or coating agent has the characteristics that it has a large adhesion or adhesion to metal, porcelain, concrete, etc., and also has a large mechanical strength such as shear strength and tensile strength. is doing.

However, the epoxy resin has a problem that flexibility and impact resistance are small, and when it is used as an adhesive or a coating agent, it is easily peeled from the surface to be coated and cracks are easily generated. ing.

In order to solve these problems, a rubber-like substance is dispersedly contained in the epoxy resin to modify the epoxy resin to improve flexibility and impact resistance.

Conventionally, the following methods have been proposed as methods for modifying an epoxy resin. (1) A method of mixing a liquid rubber such as acrylonitrile-butadiene rubber containing a reactive functional group for the epoxy resin in the molecule with the epoxy resin (for example, Clayton)
A. May, Epoxy Resins, Marcel
Dekker Inc. (1988)). (2) A method in which a monomer having a functional group reactive with an epoxy resin such as acrylate and acrylic acid is polymerized in the epoxy resin (in-situ polymerization) to disperse rubber particles in the epoxy resin (JP-A-58-58). 830
14 and 59-138254). (3) A method in which a reactive solid rubber and a liquid epoxy resin are kneaded with a rubber roll or a pressure kneader, and the epoxy resin is modified with the reactive solid rubber (JP-A-57-70167).
No. 59-78282). (4) A coagulated product of a partially crosslinked rubbery copolymer containing a certain residual volatile content is mixed and dispersed in a compound having an epoxy group, and then the residual volatile content is removed from the obtained composition. , A method for producing a modified epoxy composition (see JP-A-3-26716).

[0006]

However, according to the above method, the modified epoxy composition cannot be obtained efficiently, and the rubber-like substance is dispersed in the epoxy resin sufficiently uniformly. I can't. That is, in the above method (1), the dispersibility of the particles of the liquid rubber depends on the type of epoxy resin and the curing conditions, physical properties with good reproducibility cannot be obtained, and the stability of the modified epoxy resin is poor. There's a problem. The above method (2) has a problem that the dispersed rubber particles are likely to agglomerate or coagulate, and the viscosity of the composition is greatly increased. In the above method (3), in order to obtain a uniform composition, it is necessary to add the liquid epoxy resin to the reactive solid rubber little by little over a long period of time, which is extremely low efficiency. According to the method (4), it is possible to obtain a modified epoxy composition having a somewhat high dispersibility of rubber particles. However, depending on the shape and particle size of the rubber-like copolymer coagulated product to be dispersed, a lump of the rubber-like copolymer may remain in the obtained composition. When such a composition is cured, the resulting cured product does not have sufficient physical properties. In order to obtain a composition suitable for use as an adhesive,
After the dispersion and mixing of the partially crosslinked rubbery copolymer, a step of removing residual volatile components is essential. However, the step of removing the residual volatiles from the composition after dispersion and mixing is complicated,
It is not preferable in terms of manufacturing efficiency.

The present invention has been made under the circumstances described above, and an object thereof is to provide a modified epoxy composition having high dispersibility of rubber-like particles and excellent characteristics including adhesiveness. Another object of the present invention is to provide a method for producing a modified epoxy composition which can be produced extremely efficiently.

[0008]

The method for producing a modified epoxy composition according to the present invention is a method in which a rubber-like polymer [component (A)] is dispersed in a particle having an epoxy group [component (B)] in a particulate form. In the method for producing a modified epoxy composition comprising:
A powder of the component (A) having a particle diameter of 0.5 mm or less, which is obtained by coagulating and pulverizing a rubber-like polymer latex, is blended with the component (B) and uniformly dispersed.

The present invention will be described in detail below. The modified epoxy composition obtained by the present invention is a composition in which the component (A) composed of a rubbery polymer is dispersed in a particle form in the component (B) composed of a compound having an epoxy group.

The component (A) used in the present invention is a component composed of a rubber-like polymer. As a preferable rubbery polymer which constitutes the component (A), an unsaturated compound having a functional group (hereinafter referred to as “functional group-containing monomer a ₁ ”) and a crosslinkable monomer (hereinafter referred to as “crosslinkable monomer a ₂ ”) And a cross-linked rubber-like copolymer (hereinafter, referred to as “copolymer (A)”) obtained by a copolymerization reaction of these with another unsaturated compound copolymerizable with these (hereinafter referred to as “copolymerizable monomer a ₃ ”). Say)
Can be mentioned. This copolymer (A) has rubber-like elasticity at room temperature, and its glass transition temperature (Tg) is usually 0 ° C. or lower, preferably −2.
It is set to 0 ° C or lower.

Specific examples of the functional group-containing monomer a _{1 used in} the copolymerization reaction include a carboxyl group-containing compound and an acid anhydride group described as "monomer (III)" in JP-A-3-26716. Examples thereof include a containing compound, an epoxy group containing compound, an amino group containing compound, an amide group containing compound, a hydroxyl group containing compound, an isocyanate group containing compound and a phosphoric acid group containing compound. Among the functional groups contained in the functional group-containing monomer a ₁ , a carboxyl group, an acid anhydride group and an epoxy group are preferable because each of them has an appropriate reactivity with the component (B) composed of a compound having an epoxy group. Copolymer (A)
The proportion of the functional group-containing monomer a ₁ therein is usually 1 to 20% by weight, preferably 2 to 15% by weight.

Crosslinkable monomer a _{2 used} for copolymerization reaction
As specific examples of, divinylbenzene, diallyl phthalate, ethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, etc.,
Examples thereof include compounds having a plurality of polymerizable double bonds in the molecule. By using the crosslinkable monomer a ₂ , the gel content of the copolymer (A) obtained can be improved. Here, the "gel content" means that about 1 g of the polymer is dipped in 100 ml of methyl ethyl ketone, and the gel content is 2 at room temperature.
It refers to the weight ratio of the insoluble matter after standing for 4 hours. The gel content of the copolymer (A) is preferably 20% by weight or more, more preferably 40% by weight or more, and particularly preferably 40 to 99% by weight. Gel content 20
If it is less than wt%, the dispersibility of the copolymer (A) in the component (B) tends to be insufficient. The proportion of the crosslinkable monomer a ₂ in the copolymer (A) is usually 0.1 to 2
The content is 0% by weight, preferably 0.5 to 10% by weight.

The copolymerizable monomer a _{3 used in the} copolymer reaction is not particularly limited as long as it is a compound copolymerizable with the functional group-containing monomer a ₁ and the crosslinkable monomer a ₂ . Specific examples of the copolymerizable monomer a ₃ include conjugated dienes such as butadiene, dimethyl butadiene, isoprene, chloroprene and derivatives thereof, and (meth) acrylic acid derivatives such as (meth) acrylonitrile and (meth) acryl. Methyl acid,
Ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth)
Lauryl acrylate, polyethylene glycol (meth)
Acrylate, polypropylene glycol (meth) acrylate, diglycidyl ether of bisphenol A,
Epoxy (meth) acrylate, urethane (meth) acrylate and the like, olefins such as ethylene, propylene, 1-butene, 2-butene, isobutene and 1-pentene, aromatic vinyl compounds such as styrene and methylstyrene. You can Copolymer (A)
The proportion of the copolymerizing monomer a ₃ in the medium, is usually 60 to 98.9% by weight, preferably 75 to 97.
It is set to 5% by weight.

A suitable combination formulation of the monomers constituting the copolymer (A) is exemplified below. [Exemplary formulation 1] Functional group-containing monomer a ₁ ... 1 to 20% by weight, polyfunctional vinyl compound (crosslinkable monomer a ₂ ) ...
0.2 to 10 wt% of acrylonitrile and / or styrene (copolymerizable monomer a ₃₎ ... 13 to 50 wt% butadiene and / or isoprene (copolymerizable monomer a ₃₎ ... 40 to 80 wt%

[Exemplary Formulation 2] Functional group-containing monomer a ₁ ... 1 to 20% by weight, polyfunctional vinyl compound (crosslinkable monomer a ₂ ).
0.2 to 10% by weight alkyl (meth) acrylate and / or alkoxy (meth) acrylate (copolymerizable monomer a ₃ ).
... 10 to 99 wt% The above monomers and other copolymerizable monomers (copolymerizable monomer a ₃₎ ... 0 to 80 wt%

[Exemplary Formulation 3] Functional group-containing monomer a ₁ ... 1 to 20% by weight, polyfunctional vinyl compound (crosslinkable monomer a ₂ ) ...
0.2 to 10 wt% of acrylonitrile and / or styrene (copolymerizable monomer a ₃₎ ... 5 to 50 wt% butadiene and / or isoprene (copolymerizable monomer a ₃₎ ... 2 to 60 wt% alkyl (meth) acrylate And / or alkoxy (meth) acrylate (copolymerizable monomer a ₃ )
… 5-65% by weight

[Exemplary Formulation 4] Functional group-containing monomer a ₁ ... 1 to 20% by weight, polyfunctional vinyl compound (crosslinkable monomer a ₂ ) ...
0.2 to 10% by weight Butadiene and / or isoprene (copolymerizable monomer a ₃ ) ... 70 to 98.8% by weight

The copolymer (A) used in the present invention can be produced, for example, by an emulsion polymerization method. Here, the emulsion polymerization method uses an anionic, cationic, nonionic and amphoteric surfactant as an emulsifier, or a mixed system thereof, and in the presence of a molecular weight modifier, a radical polymerization initiator causes functionalization. The polymerization reaction of the group-containing monomer a ₁ , the crosslinkable monomer a ₂ and the copolymerizable monomer a ₃ is started, and when a predetermined polymerization conversion rate is reached, a reaction terminator is added to stop the polymerization reaction. This is a method of obtaining a copolymer latex by removing the unreacted monomer by steam distillation or the like.

The copolymer (A) can also be produced by a suspension polymerization method, a solution polymerization method or the like. For example, in the case of the solution polymerization method, the functional group-containing monomer a ₁ and the copolymerizable monomer a ₃ are mixed to perform solution polymerization, and the obtained copolymer solution is dispersed in water containing an emulsifier to form a latex. After that, a method of adding a crosslinkable monomer a ₂ , a radical polymerization initiator or the like to crosslink, and adding a compound containing two or more reactive groups in the molecule capable of reacting with the functional group of the functional group-containing monomer a _1. And can be crosslinked.

The component (B) used in the present invention is a component composed of a compound having an epoxy group. The compound having an epoxy group (hereinafter referred to as “epoxy group-containing compound”) is not particularly limited, and examples thereof include a condensation product of epichlorohydrin and a polyhydric alcohol, a condensation product of epichlorohydrin and a polyhydric phenol, and epichlorohydrin. Condensation product of alkyd with novolac, cycloaliphatic epoxy compound, glycidyl ester epoxy compound, glycidyl amine epoxy compound, heterocyclic epoxy compound, epoxy compound derived from (co) polymer of polyolefin, glycidyl methacrylate ( Epoxy compound obtained by co-polymerization reaction, epoxy compound obtained from glyceride of highly unsaturated fatty acid, polyalkylene ether type epoxy compound, bromine-containing epoxy compound, fluorine-containing epoxy compound, etc.
Epoxy compounds described in JP-A-6 can be mentioned.

The component (B) may contain a curing agent and / or a curing accelerator for the above epoxy group-containing compound. Such a curing agent and / or a curing accelerator should be selected from various ones according to the curing type of the modified epoxy composition, for example, two-component type, one-component type, thermosetting type, photo-curing type and the like. And specifically, JP-A-3-2
The curing (accelerating) agent described in Japanese Patent No. 6716 can be preferably used. The amount of the curing agent used is usually such that the active hydrogen groups of the curing agent and the epoxy groups of the epoxy group-containing compound are almost equivalent. In addition, the proper amount of the curing accelerator is selected according to the type and curing conditions.

The manufacturing method of the present invention is characterized in that the powder of the component (A) having a particle size of 0.5 mm or less is used, whereby the component (A) is a particle in the component (B). It is possible to obtain a modified epoxy composition having a uniform dispersion.

As a preferred example of the present invention, there can be mentioned, for example, a production method including the following steps. Step: A step of coagulating the latex of the copolymer (A) to obtain a coagulated product. Process: The obtained coagulated product is dehydrated and / or dried until the water content thereof is less than 15% by weight,
Then, the coagulated product is pulverized so that the particle size becomes 0.5.
A step of obtaining a solidified product powder (A) having a size of mm or less. Step: A step of mixing and dispersing the obtained solidified product powder (A) in the component (B) using a shearing stir mixer or a disperser.

Hereinafter, these steps will be described in more detail. [Step] As the latex of the copolymer (A), when the copolymer (A) is produced by emulsion polymerization in an aqueous medium, the obtained aqueous latex can be used as it is. In addition, when the copolymer (A) is produced by solution polymerization, an aqueous latex obtained by adding an aqueous medium, an emulsifier and the like to the copolymer solution, and then subjecting it to phase inversion by stirring or the like may be used. In addition, when the copolymer (A) is previously separated from the dispersion by coagulating the copolymer from the latex or removing the solvent from the copolymer solution, or when using a commercially available copolymer For this, an aqueous latex obtained by dissolving or dispersing this copolymer (A) in a suitable solvent and then subjecting it to phase inversion in the same manner as in the case of the solution polymerization may be used.

The method for coagulating the aqueous latex of the copolymer (A) is not particularly limited, and a conventional method such as, for example,
It can be performed by adding a coagulant or an organic solvent. Examples of the coagulant added here include calcium chloride, magnesium sulfate, polyvalent metal salts such as aluminum sulfate, sodium chloride and sulfuric acid, and examples of the organic solvent include methanol and ethanol. Examples thereof include water-soluble organic solvents such as alcohols, acetone and methyl ethyl ketone. It is also possible to coagulate with a nonionic surfactant. Specifically, using a nonionic surfactant as an emulsifier, after emulsion polymerization at a temperature below the cloud point of the nonionic surfactant, the latex obtained is heated above the cloud point, or as an emulsifier. A method of adding a nonionic surfactant having a cloud point lower than that of the nonionic surfactant used, an electrolyte alcohol, a fatty acid, and the like, and then heating, an anionic and / or cationic surfactant, and a nonionic surfactant After performing emulsion polymerization using and as an emulsifier, a method of adding a nonionic surfactant or electrolyte having a lower cloud point than the nonionic surfactant used as an emulsifier, and then heating, anionic and / or cation Emulsion polymerization using a surface-active agent as an emulsifier, then adding a nonionic surface-active agent and an electrolyte, and then heating Therefore, it may be allowed to solidify. In addition, as the heating methods 1 to 3, for example, a method of blowing steam can be exemplified.

The coagulated product of the copolymer (A) thus obtained may be washed with water if necessary.

[Step] In the step, first, the coagulated product of the copolymer (A) is dehydrated by a centrifugal dehydrator or the like. After the dehydration treatment, the coagulated product may be dried. Here, the water content of the coagulated product after the dehydration (/ drying) treatment is preferably less than 15% by weight, and more preferably less than 5% by weight.
In this way, by performing the dehydration (drying) treatment of the solidified product, the water content of the modified epoxy composition finally obtained can be suppressed to 1% by weight or less. And
The modified epoxy composition having a water content of 1% by weight or less can be suitably used for applications such as adhesives.
Moreover, since a certain amount of water is removed at the stage of the coagulated product, there is no need to perform a water removal operation after the dispersion and mixing of the copolymer (A), which is also preferable from the viewpoint of production efficiency.

Next, the dehydrated (/ dried) solidified product is pulverized to obtain a solidified product powder (A). The particle size of the coagulated product powder (A) is 0.5 mm or less, and preferably 0.25 mm or less. This particle size is 0.5m
By performing the pulverizing treatment until it becomes m or less, the dispersion treatment (step) of the solidified product powder (A) in the component (B) is efficiently performed in a short time, and moreover, from the examples described later. As is apparent, the dispersibility of the copolymer (A) in the modified epoxy composition can be improved. When the particle size of the coagulated product powder (A) exceeds 0.5 mm, not only does the dispersion treatment take time, but also the dispersibility becomes insufficient, and the copolymer ( The lump of A) may remain. Examples of a crusher used for crushing the solidified product include "Turbomill" [manufactured by Turbo Industry Co., Ltd.] and "ZM-1" [manufactured by Nippon Seiki Seisakusho Co., Ltd.]
And so on. It should be noted that a filler such as calcium carbonate or talc can be added during the pulverization treatment, which can prevent the coagulated powder (A) from aggregating. In addition, prior to this crushing process, the coagulated product is crushed to a size of 1 to 10 m.
It is preferable to set it to about m.

[Step] The step is the solidified powder (A)
Is a step of mixing and dispersing in the component (B). In this step, first, the solidified product powder (A) obtained in the above step and the component (B) are mixed in a predetermined ratio. Here, as the blending amount of the solidified product powder (A),
It is usually 1 to 100 parts by weight, preferably 1 to 50 parts by weight, and more preferably 2 to 30 parts by weight, relative to 100 parts by weight of the component (B). If the amount of the coagulated product powder (A) is less than 1 part by weight, the cured product of the obtained modified epoxy composition is unlikely to exhibit the effect of improving the adhesiveness and impact resistance. On the other hand, the amount is 100 parts by weight. If it exceeds the amount, the viscosity of the modified epoxy composition tends to be high and handling tends to be difficult.

Then, this compounding system is put into a shearing agitating mixer or a dispersing machine, and a shearing force is applied thereto,
Coagulated product powder (A) is mixed and dispersed in component (B). As the shearing and stirring mixer used for the dispersion treatment, there are "Homo Disper" and "Homo Mixer" [Tokuseki Kika Kogyo Co., Ltd.].
And the like, and examples of the disperser include “colloid mill” [manufactured by Nippon Seiki Seisakusho Co., Ltd.] and “My Colloider” [manufactured by Tokushu Kika Kogyo Co., Ltd.].

By performing the above steps
A modified epoxy composition is obtained in which the copolymer (A) is uniformly dispersed in the component (B) in the form of particles. In the modified epoxy composition obtained by the method of the present invention, (B)
The particle size of the copolymer (A) dispersed in the component is usually 200 to 5000Å, preferably 300 to 50.
00Å, and more preferably 500 to 4000Å.
If the particle size is less than 200Å, the viscosity of the composition becomes high and handling tends to be difficult. On the other hand, if this particle size exceeds 5000 Å, the toughness of the composition after curing tends to decrease.

If necessary, additives may be added to the modified epoxy composition obtained as described above. As such additives, for example, silica, clay, gypsum, calcium carbonate, quartz powder, kaolin, mica, sodium silicate, talc, calcium silicate, titanium compounds, fillers such as antimony compounds, pigments, organosilane compounds, Coupling agents such as organic titanate compounds,
Xylene resin, tar, dibutyl phthalate (DB
P), phosphoric acid ester, pine oil, benzyl alcohol, trimellitic acid ester, diallyl phthalate monomer, extender such as xylene and toluene, and anti-aging agent.

The modified epoxy composition obtained by the present invention, when subjected to a curing treatment, becomes a cured product having high adhesiveness and impact resistance. When the functional group of the functional group-containing monomer a ₁ constituting the copolymer (A) is a carboxyl group, the surface of the dispersed particles of the copolymer (A) is treated prior to the curing treatment with a curing agent or the like. It is preferable to carry out a preliminary reaction in which the carboxyl group of 1 is previously reacted with the epoxy group in the component (B). This pre-reaction is carried out in the absence of a catalyst or triphenylphosphine, phosphonium halide, triethanolamine, chromium complex of acetylacetonate, chromium diisopropylsalicylate, tetraethylammonium chloride,
It is carried out by heating at room temperature to about 200 ° C. for several hours in the presence of a catalyst such as triisoamylamine, tributylamine, trisdimethylaminomethylphenol.

[0034]

EXAMPLES Examples of the present invention will be described below.
The invention is not limited to these examples. In the following, "part" means "part by weight". Also,
The “water content” is a value obtained from the weight change (heating loss) when heated at 105 ° C. for 2 hours.

<Production Example of Copolymer (A)> [Copolymers A-1 to A-3] According to the formulation shown in Table 1 below, emulsion polymerization was carried out in an autoclave set at a temperature of 10 ° C. In this production example, methacrylic acid and divinylbenzene were added after the polymerization conversion rate reached 50%. After the conversion of polymerization reached 90%, 0.2 part of diethylhydroxylamine and 0.5 part of sodium dimethylcarbamate were added to the reaction system to stop the polymerization reaction, and then steam distillation was performed to remove unreacted monomers. Were removed to obtain each latex of copolymers A-1 to A-3.

[0036]

[Table 1]

[Copolymers A-4 to A-6] According to the formulation shown in Table 2 below, emulsion polymerization was carried out in an autoclave set at a temperature of 50 ° C. In this manufacturing example,
Methacrylic acid, acrylonitrile and divinylbenzene were added after the polymerization conversion reached 50%. After the polymerization conversion rate reached 95%, 0.2 part of diethylhydroxylamine was added to the reaction system to stop the polymerization reaction, and then unreacted monomers were removed by steam distillation to obtain a copolymer A- Each latex of 4 to A-6 was obtained.

[0038]

[Table 2]

Example 1 [Step] 1 part of alkylated phenol (anti-aging agent) was added to 100 parts of the copolymer A-1 in the latex of the copolymer A-1 obtained in the above production example. Part was added, and an aqueous solution of calcium chloride (coagulant) was added to coagulate. Then, each of these coagulated products was washed twice with water.

[Step] The coagulated product of the copolymer A-1 obtained in the above step was dehydrated by a centrifugal dehydrator, coarsely crushed, and further dried at 90 ° C. for 2 hours. The size of the solidified product after drying was about 10 mm or less, and the water content of the solidified product was 0.5% by weight. Then, the coagulated product powder A is obtained by pulverizing the coagulated product which is dehydrated, crushed and dried.
-1 was obtained. The crushing process of the solidified product is the crusher "ZM-1"
0.25m using [manufactured by Nippon Seiki Co., Ltd.]
The powder that has passed through the screen of m.
It was set to -1. As the particle size distribution of the coagulated product powder A-1, 0.25 to 0.125 mm is 65%, 0.125 m
m or less was 35%.

[Step] 15 parts of the coagulated product powder A-1 obtained in the above step was added to 85 parts of a bisphenol F-based epoxy compound “Epicoat 807” (Okaka Shell Epoxy Co., Ltd., epoxy equivalent 160-175). The bisphenol F epoxy is added by adding and blending, and then the blending system is put into a shear stir mixer “Homomixer” (manufactured by Tokushu Kika Kogyo Co., Ltd.) and mixed at 90 ° C. for 30 minutes. A modified epoxy composition was produced in which the copolymer A-1 was dispersed in the compound in the form of particles. The modified epoxy composition had a water content of 0.2% by weight.

<Examples 2 and 3> Bisphenol was prepared in the same manner as in Example 1 except that latexes of copolymers A-2 to A-3 were used in place of the latexes of copolymer A-1. In the F-based epoxy compound, the copolymer A-2 ~
A modified epoxy composition in which A-3 was dispersed in the form of particles was produced. The particle size distribution of the coagulated product powders of the copolymers A-2 to A-3 was the same as the particle size distribution of the coagulated product powder of the copolymer A-1. The water content of the coagulated product of the copolymers A-2 to A-3 after dehydration, crushing and drying is 0.2 to 1.0% by weight, and the water content of the obtained modified epoxy composition is It was 0.1 to 0.3% by weight.

Example 4 [Step] Example 1 except that the latex of the copolymer A-4 was used in place of the latex of the copolymer A-1.
A coagulated product of copolymer A-4 was obtained in the same manner as in the step of.

[Step] The coagulated product of the copolymer A-4 obtained in the above step was dehydrated by a centrifugal dehydrator and then crushed. The size of the solidified product after the crushing was about 10 mm or less, and the water content of the solidified product was 14.5% by weight. Next, the dehydrated and roughly crushed coagulated product was pulverized to obtain coagulated product powder A-4. The crushing process of the coagulate is
Using a crusher "ZM-1" (manufactured by Nippon Seiki Seisakusho Co., Ltd.), powder passing through a 0.25 mm screen was collected to obtain coagulated powder A-4. Coagulated product powder A-
As the particle size distribution of 4, 0.25 to 0.125 mm is 8
0% and 0.125 mm or less were 20%.

[Step] 15 parts of the coagulated product powder A-4 obtained in the above step was added to 85 parts of the bisphenol F-based epoxy compound "Epicoat 807" (produced by Yuka Shell Epoxy Co., Ltd.) and blended. Then, this blending system is subjected to a shear stirring mixer "Homomixer" (manufactured by Tokushu Kika Kogyo Co., Ltd.).
Then, the mixture was charged into the flask and mixed at 90 ° C. for 30 minutes to prepare a modified epoxy composition in which the copolymer A-4 was dispersed in the bisphenol F epoxy compound in the form of particles. The modified epoxy composition had a water content of 0.
It was 3% by weight.

<Examples 5 to 6> Bisphenol was prepared in the same manner as in Example 4 except that latexes of copolymers A-5 to A-6 were used in place of the latexes of copolymer A-4. Copolymer A-5 to F epoxy compound
A modified epoxy composition in which A-6 was dispersed in the form of particles was produced. The particle size distribution of the coagulated product powder of the copolymers A-5 to A-6 was the same as the particle size distribution of the coagulated product powder of the copolymer A-4. The water content of the coagulated products of the copolymers A-5 to A-6 after dehydration and coarse crushing is 12.
3 to 13.8% by weight, and the modified epoxy composition obtained had a water content of 0.2 to 0.4% by weight.

<Comparative Example 1> N containing carboxyl groups at both ends
Liquid rubber made of BR "Hycar CTBN1300
X 13 "(manufactured by BF Goodrich Co.) 15 parts by weight, and bisphenol F-based epoxy compound" Epicoat 807 "8
A modified epoxy composition was prepared by mixing 5 parts.

<Comparative Example 2> Crushing of solidified product (process)
A modified epoxy composition was produced in the same manner as in Example 1 except that the above was not performed. The size of the dispersed coagulated product was about 1 to 10 mm. In this comparative example, stirring was carried out for 1 hour or more by a shear stir mixer “Homomixer”. However, in the obtained composition, the copolymer A-
A lump of 1 or more and having a size of 1 mm or more still remained.

Example 7 12.7 of coagulated product powder A-1
Copolymer A- was added to the bisphenol F-based epoxy compound in the same manner as in Example 1 except that 5 parts were added to 72.25 parts of the bisphenol F-based epoxy compound "Epicoat 807". A modified epoxy composition in which 1 was dispersed in the form of particles was produced. The water content of this modified epoxy composition was 0.1% by weight.

<Examples 8 to 9> Bisphenol F was prepared in the same manner as in Example 7 except that each of the copolymers A-2 to A-3 was used in place of the latex of the copolymer A-1. A modified epoxy composition was produced in which each of the copolymers A-2 to A-3 was dispersed in a particulate epoxy compound. The water content of these modified epoxy compositions was 0.1 to 0.3% by weight.

<Example 10> 12. of coagulated product powder A-4
Bisphenol F was prepared in the same manner as in Example 4 except that 75 parts were added to 72.25 parts of the bisphenol F-based epoxy compound "Epicoat 807" to prepare a compounding system.
A modified epoxy composition in which the copolymer A-4 was dispersed in a particulate epoxy compound in the form of particles was produced. The modified epoxy composition had a water content of 0.2% by weight.

<Examples 11 to 12> Bisphenol F was prepared in the same manner as in Example 7 except that each of the copolymers A-5 to A-6 was used in place of the latex of the copolymer A-4. Copolymers A-5 to A-6 in the epoxy compound
A modified epoxy composition was produced in which each of these was dispersed in the form of particles. The water content of these modified epoxy compositions was 0.2 to 0.4% by weight.

<Comparative Example 3> N containing carboxyl groups at both ends
Liquid rubber made of BR "Hycar CTBN1300
X13 "12.75 parts was mixed with bisphenol F-based epoxy compound" Epicoat 807 "72.25 parts to produce a modified epoxy composition.

<Comparative Example 4> Crushing of solidified product (process)
A modified epoxy composition was produced in the same manner as in Example 7 except that the above was not performed. In this comparative example, stirring was carried out for 1 hour or longer by means of a shear stir mixer “Homomixer”, but in the obtained composition, a lump having a size of 1 mm or more made of the copolymer A-1 still remained. Was.

<Adhesiveness Test (I)> Using the modified epoxy compositions obtained in Examples 1 to 6 and Comparative Examples 1 to 2 as an adhesive, tensile shear strength and T-type peel strength were measured. An impact test was performed to evaluate the adhesive properties.

Tensile shear strength According to the method of JISK6850. As the adherend, a stainless steel plate SUS washed and degreased with methylene chloride
304 was used at a measurement temperature of 23 ° C. and a pulling speed of 5 mm / min. T-type peel strength According to the method of JISK6854. As the adherend, a stainless steel plate SUS washed and degreased with methylene chloride
304, measurement temperature 23 ℃, pulling speed 100 mm /
Went in minutes. Impact test Cold-rolled steel plate (100mm x 25mm)
X 3.2 mm) was sanded with # 240 sandpaper and washed and degreased with trichlorethylene.
A modified epoxy composition was applied within a range of x25 mm and cured to prepare a test piece. Using a DuPont type impact tester, a weight of 500 g was dropped onto a test piece from a height of 20 cm at 23 ° C., and the number of times until a crack was generated in an adhesive portion of the test piece was measured.

The modified epoxy composition was cured by adding 57 parts of a curing agent "Ancamine 1618" (manufactured by ACI Japan), 40 parts of calcium carbonate and "Aerosil # 200" to 100 parts of the modified epoxy composition. 3 parts (manufactured by Nippon Aerosil Co., Ltd.) were added and mixed, and the mixture was heated at 140 ° C. for 1 hour. In addition, regarding the modified epoxy compositions obtained in Examples 1 to 4 and Comparative Example 2 using the copolymer (A) having a carboxyl group, triphenylphosphine. After adding 1 part and heating at 90 ° C. for 4 hours (preliminary reaction), curing was performed. The above results are shown in Table 3 below.

<Adhesion Test (II)> Examples 7 to 12 above
Using the modified epoxy compositions obtained in Comparative Examples 3 to 4 as an adhesive, tensile shear strength measurement, T-type peel strength measurement, and impact test were performed to evaluate the adhesive properties.

Tensile shear strength According to the method of JISK6850. As the adherend, a cold rolled steel plate was ground with # 240 sandpaper,
The test piece was washed and degreased with trichlorethylene, and the measurement temperature was 23 ° C. and the pulling rate was 5 mm / min. T-type peel strength According to the method of JISK6854. As the adherend, a cold rolled steel plate was ground with # 240 sandpaper,
The test piece was washed and degreased with trichlorethylene, and the measurement was performed at a temperature of 23 ° C. and a pulling rate of 100 mm / min. Impact test Cold-rolled steel plate (100mm x 25mm)
X 3.2 mm) was sanded with # 240 sandpaper and washed and degreased with trichlorethylene.
A modified epoxy composition was applied within a range of x25 mm and cured to prepare a test piece. Using a DuPont type impact tester, a weight of 500 g was dropped onto a test piece from a height of 30 cm at 23 ° C., and the number of times until a crack was generated in an adhesive portion of the test piece was measured.

The modified epoxy composition was cured by mixing 100 parts of each modified epoxy composition with 8 parts of dicyandiamide, 1 part of dimethylbenzylamine and 50 parts of calcium carbonate and heating at 170 ° C. for 30 minutes. It was done by doing. Further, Examples 7 to 10 and Comparative Example 4 using the copolymer (A) having a carboxyl group.
With respect to the modified epoxy composition obtained in step 1, 0.1 parts of triphenylphosphine was added to 100 parts of the modified epoxy composition and heated at 90 ° C. for 4 hours (preliminary reaction).
It was subsequently cured. The above results are also shown in Table 3 below.

[0061]

[Table 3]

<Measurement of Particle Size of Copolymer A-1> Example 1
100 parts of the modified epoxy composition obtained in 1 above and 10 parts of triethylenetetramine were mixed and cured under each curing condition of 7 days at room temperature and 1 hour at 140 ° C.
An ultrathin section was prepared from the obtained two kinds of cured products using a microtome, stained with osmium, and then the particle size and dispersion state of the copolymer A-1 particles were observed by a transmission electron microscope. On the other hand, the particle size of the copolymer A-1 used in Example 1 in the latex was observed using a Coulter submicroparticle analyzer "Model N-4" (manufactured by Nikkaki Co., Ltd.). As a result, the particle size of the cured product obtained under the curing conditions, the particle size of the cured product obtained under the curing conditions, and the particle size in the latex were all about 700Å,
Further, there is no variation in the curing conditions and the distance between the particles of the copolymer A-1 in the cured product obtained under the curing conditions. Therefore, it is understood that the dispersibility of the particles is good regardless of the curing conditions.

<Relationship Between Particle Size of Coagulated Powder and Adhesive Properties>
Modified epoxy composition in the same manner as in Example 1 except that the maximum particle size of the coagulated powder was changed as shown in Table 4 below by changing the screen used for the pulverization treatment of the copolymer A-1. Manufactured. The particle size distribution of the solidified product powder collected by passing through a 0.5 mm screen is 0.5% to 0.25 mm, 17%, 0.25 to 0.1%.
25 mm was 75%, and 0.125 mm or less was 8%.

With respect to each of the obtained modified epoxy compositions, the dispersed state was observed, and the tensile shear strength, T-type peel strength and impact test were conducted in the same manner as in the "Adhesion test (I)". Was performed to evaluate the adhesive properties. The results are also shown in Table 4.

[0065]

[Table 4]

As is clear from the results shown in Table 4, the dispersibility of the solidified powder can be improved only by using the solidified powder having the maximum particle size of 0.5 mm or less. When the maximum particle size of the coagulated powder exceeds 0.5 mm, the dispersibility becomes insufficient, and a lump of 0.5 mm or more remains, and the adhesiveness and impact resistance of the composition are poor. Sufficient and not suitable as an adhesive.

[0067]

According to the production method of the present invention, a modified epoxy composition in which a crosslinked rubbery copolymer is uniformly dispersed can be produced extremely efficiently. The modified epoxy composition obtained by the present invention is excellent in various properties such as adhesiveness and impact resistance, and is used as an adhesive, a coating agent, a laminate, a composite material, an electric casting material, an impregnating varnish, a printed circuit board, a printed circuit board. It can be suitably used as an adhesive for resins, resin molds, paints, lining materials, sealing materials, sealing materials, damping materials, and other molding materials.

Claims (1)

[Claims] 1. A method for producing a modified epoxy composition comprising a rubbery polymer [component (A)] dispersed in a compound having an epoxy group [component (B)] in the form of particles. A method for producing a modified epoxy composition, characterized in that a powder of component (A) having a particle size of 0.5 mm or less, obtained by coagulating and pulverizing latex, is mixed with component (B) and uniformly dispersed. ..