JPS59170114A - Epoxy fine particles and their preparation - Google Patents

Abstract

PURPOSE:To specific amount of piperazine or its derivative is added to an uncured epoxy emulsion as a curing agent to produce fine particles of epoxy resin with specific particle sizes, which is suitable for use as a filler, reinforcing agent or chromatography column. CONSTITUTION:An uncured epoxy compound, preferably composed of 50- 100wt% of an epoxy compound bearing 2 or more epoxy groups and 0-50wt% of an epoxy compound bearing 1 epoxy group, is mixed with an emulsifier and the resultant uncured epoxy emulsion is combined with a piperazine or its derivative of the formula (R, R' are H, residue of 1-4C hydrocarbon) as a curing agent, more than 15%, preferably less than 1,000% of the amine equivalent amount which can be calculated stoichiometrically from the epoxy value of the emulsion to give the objective epoxy fine particles of 1-50 micrometer sizes.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to the production of epoxy emulsions with average particle diameters of 1 to 1.
The present invention relates to a method for preparing epoxy-based spherical fine particles of 50 μm and a relatively narrow particle size distribution.

Background of the Invention Fine particles made of organic polymers, especially spherical fine particles, are used as fillers and reinforcing agents for rubber and plastics.

Also, candy coloring agents and fillers such as paints, pigments, and adhesives.

It is used as a reinforcing agent for almost the same purpose as inorganic fillers and inorganic pigments, but its main feature is that it is lighter in weight than inorganic materials. This term is further characterized by making organic fine particles hollow or porous. moreover.

Unlike inorganic materials, it is possible to add functional groups to the surface of organic particles, which has led to the discovery of unique uses. For example, a double bond or an aldehyde group on the surface of 9,
When Kamijo is functionalized by adding a carboxyl group or the like, crosslinking and reinforcing effects are added in addition to a simple filling effect, thereby further enhancing the blending effect. Furthermore, the introduction of polar groups such as amine groups and carboxyl groups allows it to exhibit a remarkable separation effect on specific chemical substances as a column packing material for chromatography. Further, functional groups 1 such as epoxy groups and aldehyde groups that can react with and covalently bond to active groups present in proteins.

Introduction of an incyanate group or the like or an amino group that can react with a crosslinking agent such as glutaraldehyde is useful for immobilizing enzymes, antigens, and antibodies. These antibodies are used in extremely small amounts as column packing material for affinity chromatography.

It can be used in a variety of fields, including clinical tests, such as antigen analysis and 9-fraction separation, and enzyme immunoassay, rapid analysis of trace components in blood.

Due to the spherical shape of organic fine particles to which these functional groups have been added, their performance in various applications9, such as analytical accuracy, sensitivity, rapidity, and handleability, are often significantly improved5, especially in Spherical particles with a narrow particle size distribution are often required and, together with the size of a single particle, are important management objectives.

PRIOR TECHNOLOGY Organic fine particles having the above shape can be obtained using 9 Conventional Mulsion Polymerization Methods!
It has been made using the suspension polymerization method. That is,
In these methods, an acrylic monomer and a radical reaction initiator are introduced into water, and the acrylic monomer is polymerized into particles in the presence or absence of an emulsifier. In addition to double bonds for polymerization, acrylic monomers contain carbonacyl groups, sulfos groups, and amide groups.

Fine particles having functional groups such as alcoholic hydroxyl groups can also be polymerized, and it is considered to be a very effective method for preparing fine particles depending on the purpose.

However, the emulsion polymerization method generally uses 0
．． It is said that it is advantageous in producing uniform spherical fine particles with a size of about 1 to 0.5 μm, and is not suitable for producing uniform fine particles with a size of 1 μm or more. The reason for this is that the time required for production increases rapidly as the particle size increases, and the distortion of the 9 particles2.
This is because an increase in particle size distribution is observed. Furthermore, in the case of suspension polymerization, it is convenient to obtain much larger particles than emulsion polymerization, but in general, the particle shape is not necessarily spherical, and the particle size distribution is usually extremely wide.

Another disadvantage of using an acrylic monomer as a starting material is that it is not possible to produce fine particles containing a large amount of ethylenic double bonds within the particles, as expected from the principle of double polymerization. The double bond is an important active group because of its own crosslinking ability and its ability to be activated to suit the purpose of using the microparticles, such as the addition of amines or the formation of an oxirane ring by oxidation.

OBJECTS OF THE INVENTION One of the objects of the present invention is that, as mentioned above, it is difficult to make polymers of 1 to 50 μm using emulsion polymerization or suspension polymerization.
The present invention provides uniform spherical fine particles and a method for producing the same. Also, it is difficult to make from polymerization of acrylic monomer9.
The object of the present invention is to provide fine particles having a large number of double bonds within the particles and a method for producing the same. Another object of the present invention is to provide functional fine particles having an amino group or an epoxy group within the particles and having high 2-reactivity, and a method for producing the same.

As can be easily inferred from the above explanation, the epoxy-based fine particles that can be prepared according to the present invention can be used as fillers, reinforcing agents, cross-linking agents, columns for chromatography, enzyme immunoassays, etc. as is or by undergoing some kind of activation treatment. It is expected that it will find useful applications in many fields, including as a reagent for industrial use.

Composition of the invention The details of the present invention will be sequentially explained below.

The gist of the present invention is to add piperazine or a derivative thereof to an unhardened epoxy emulsion and harden it into nine spherical particles to prepare epoxy fine particles each having a particle size of 1 to 50 μm.

Epoxy emulsion is a water-based paint and adhesive.

It is well known and has been traditionally used as a cement stiffener. In these applications, unique applications have been developed for solvent-type or solvent-free epoxy resins, taking advantage of their water-based properties. but,
As in the case of Epokin Emma resin after curing, it becomes an integrated resin-like substance, and water is always removed during or after curing.

In other words, in the conventionally used epoxy emulsion, the emulsion particles are ultimately used in a state of coalescence. It is relatively easy to combine the epoxy emulsions in this manner, and unless a particular limit is set on the strength or the like, changes can occur without any particular intention.

The main feature of the present invention is that the epoxy fine particles are obtained by curing the particles dispersed as an emulsion in a nearly intact state without combining the epoxy emulsions as described above.

Since the obtained particles themselves do not exhibit bonding properties at room temperature, the particles after curing do not coalesce or exhibit adhesion to other substances at room temperature. This point is the most distinctive feature of the present invention, and is different from the conventionally known curing of epoxy emulsions.

A technique for curing an epoxy compound into fine particles is disclosed in JP-A-53-73249. This method does not include an amine-based curing agent, which is generally recognized as a curing agent for epoxy compounds, as a curing agent.

However, according to the inventor's studies, it was found that the most important point in curing the epoxy emulsion into particles is the type of curing agent. As a result of intensive studies on various curing agents, the present invention was arrived at. It is.

The above-mentioned piperazine compounds are used in the present invention. In addition to piperazine and its derivatives, many other compounds such as ethanolamine, ethylenediamine, and diethylenetriamine can be considered as water-soluble N-curing agents that can generally cure epoxy compounds. Even with the use of a curing agent, the epoxy emulsion did not succeed in curing into particles, and the nine particles coalesced into a large size, or the emulsion was completely destroyed and phase-separated into water and the epoxy compound.

It is important that the epoxy compound used in the uncured epoxy emulsion of the present invention has an epoxy compound having two or more epoxy groups in one molecule as a main component. Examples of such epoxy compounds include the following compounds.

First, as a product having two epoxy groups, there is a bisphenol A type glycidyl ether at both ends.

Diglycidyl ether of polyethylene glycol.

Diglycidyl ether of polypropylene glycol, neopentyl glycol diglycidyl ether and 1,6-
Diglycidyl ethers of aliphatic alcohols such as hexanesiol diglycidyl ether, alicyclic diglycidyl ethers such as glycidyl ethers at both ends of hydrogenated bisphenol A, and alkylene oxide added to both terminals of bisphenols. Examples include diglycidyl ethers.

Those having 3 or more epoxy groups f include polyglycidyl ethers of aliphatic polyhydric alcohols such as glycerin triglycidyl ether and trimethylolpropane triglycidyl ether, polyglycidyl ethers of phenol novolac type compounds, and trisepoxypropylene. Isocyanurate, N, N,
N', N' -tetragrisi
Zyl m-xylenecyamine, 1,5-bis(N,
Examples include N-diglycidylaminomethyl) cyclohexane.

In the present invention, it is necessary to emulsify these epoxy compounds in water to form an emulsion. For this reason, emulsification is generally difficult with highly water-soluble epoxy compounds such as diglycidyl ether of alkylene oxide with a high degree of polymerization and glycerin diglycidyl ether, so it is not very preferable to use them frequently.

Epoxy compounds having two or more epoxy groups in the molecule and containing one or more ethylenic double bonds in the molecule are also preferably used in the present invention.

Examples of such compounds include partial (meth)acrylates of compounds having two or more epoxy groups in the molecule as described above, and partial esters with dicarboxylic acids having ethylenic double bonds such as maleic acid. Can be mentioned.

In the present invention, as the epoxy compound of the uncured epoxy emulsion, the above-mentioned epoxy compounds having two or more epoxy groups in the molecule are used alone or as a mixture.
Those containing 0 to 100% by weight are preferably used. On the other hand, in the present invention, the remaining epoxy compound preferably contains an epoxy compound having one epoxy group in two molecules, singly or as a mixture, in an amount of 0 to 60% by weight.

Examples of such epoxy compounds include the following.

Glycidyl ethers of aliphatic hydrocarbons such as 2-ethylhexylglycidyl ether and 2-methyloctylglycidyl ether In epoxy compounds having two or more epoxy groups in two molecules, leave one epoxy group and remove the remaining epoxy groups. There are products that are reacted with amines or added with hydrochloric acid, etc. It is also suitable for the present invention that an epoxy compound having one epoxy group in the molecule also has an ethylenic double bond. Examples of such compounds include glycidyl (meth)acrylate and epoxy compounds having two or more epoxy groups in the molecule, leaving one epoxy group and replacing the remaining noepoxy groups with compounds such as (meth)acrylic acid and maleic acid. Examples include those esterified with a dicarboxylic acid having an ethylenic double bond, and the reaction product of a compound with an ethylenic double bond and an alcoholic hydroxyl group, such as 2-hydroxyethyl (meth)acrylate, and epichlorohydrin. .

In order to achieve the present invention, as described above, the epoxy compound of the uncured epoxy emulsion is a compound having two or more epoxy groups in the molecule, with a weight ratio of 40 to 100, preferably 50 to 1"OO, within a molecule of 9. The weight ratio of the compound having one epoxy group in the molecule must be 0 to 60, preferably 0 to 50.If the epoxy compound having one epoxy group in the molecule exceeds 60 weight, In the curing reaction, sufficient polymerization or crosslinking cannot be achieved, resulting in products with weak physical strength or stickiness.In general, epoxy compounds with only one epoxy group in the molecule are If too much is used, the physical strength of the cured product will decrease, so it is preferable to increase the proportion of the epoxy compound having 6 or more epoxy groups.

The uncured epoxy emulsion particles of the present invention may contain other additives as long as they do not impair the present invention. The most typical additives are organic and inorganic pigments and dyes used to color epoxy particles. A blowing agent can also be used to make the fine particles porous and hollow. Antistatic agent.

Conductive agents, ultraviolet absorbers, etc. can also be added depending on the purpose. These additives are usually added before emulsifying the uncured epoxy compound and are blended by thoroughly mixing or dissolving it.

The uncured epoxy composition of the present invention is then emulsified with water. Emulsification is generally carried out with the help of an emulsifier.The emulsifier used for this purpose is not particularly limited, and any emulsifier known as an emulsifier for epoxy compounds can generally be used suitably. .

Examples of emulsifiers that can be used in the present invention include ether-type nonionic surfactants such as polyoxyethylene phenol-substituted ethers, polyoxyethylene, and polyoxypropylene block polyethers, higher fatty acid esters of polyethylene glycol, and polyhydric alcohols. These include ester-type nonionic surfactants such as fatty acid esters, and alkoxylated rosins. Further, it is also possible to use a polyamide amine-based reaction product of dimer acid and polyether diamine or aliphatic polyamine which has self-emulsifying property and can be used as an epoxy compound hardening agent.

These emulsifiers are usually used in an amount of not more than 30% by weight based on the epoxy compound, but the amount used is not particularly limited.

An emulsifier is generally used in a state mixed with an epoxy compound, but it is also possible to add an emulsifier to water and vigorously mix it with an epoxy compound containing or not containing an emulsifier.

When mixing an emulsifier and an epoxy compound, dispersion and dissolution are often easier when the mixture is heated.

Generally, the difficulty of emulsifying a compound is affected by its viscosity. When the epoxy compound has a high viscosity or is a type of epoxy compound that solidifies at room temperature.

It is difficult to emulsify sufficiently using mechanical force alone. In such cases, a diluent for the epoxy compound is used together with an emulsifier.

Diluents include ketones, alcohol at seosolves,
Examples include dioxane, aromatic hydrocarbons, and esters such as ethyl acetate.

As described above, the epoxy composition prepared using the epoxy compound and the emulsifier as its basic composition is then emulsified according to a conventional method to form an uncured epoxy emulsion I/1LiJ.

Although the emulsification method is not particularly limited, one typical method is shown below.

The above-mentioned epoxy composition containing an emulsifier is heated to room temperature to 95°C, and water in the upper B temperature range is gradually added thereto while stirring at high speed. It is generally preferable to add water intermittently rather than continuously, and a method in which addition periods and periods in which only stirring is performed is alternated is recommended. In this method, the initial addition of water forms a WlO type emulsion, but the addition of water causes a phase inversion to an O7W type emulsion. During phase inversion and after forming an O/W type emulsion, high-speed stirring is particularly required in order to reduce the particle size, make the particles uniform, and stabilize the emulsion. For this method, the emulsifier contains 1. There is also a method of directly preparing an o7'v type emulsion by gradually adding an epoxy-based composition to water under high-speed stirring.

There is a close relationship between the concentration of an epoxy emulsion and the emulsion particle size and stability, and if the concentration is too low, aggregation will occur and stability will deteriorate.

Generally, it is considered that a condition for obtaining a good emulsion is to adjust the emulsion concentration to about 10 to 80% by weight, but the present invention does not particularly limit this range. In order to prepare an emulsion with a concentration lower than this, it is common to first prepare an emulsion with a concentration within the above range and then dilute it with water to a predetermined concentration.

Epoxy emulsions are given stability in water by the action of emulsifiers, droxyethylcellulose, and carboxymethylcellulose.

A method in which a substance exhibiting protective colloidal action, such as gum arabic or polyvinyl alcohol, is added to water in advance is effective in increasing the stability of the emulsion.

In the present invention, piperazine or a derivative thereof is added to the uncured epoxy emulsion obtained as described above, and the emulsion particles are hardened into particles.

Prepare epoxy particles.

The curing agent used in the present invention as piperazine and its derivatives must have the following structure R' (R and R' are hydrogen atoms or hydrocarbon residues having 1 to 4 carbon atoms).

The present invention is achieved by adding piperazine or a derivative thereof of the structure described above on a 15 weight plate of 1 equivalent of amine calculated stoichiometrically from the epoxy value of the epoxy emulsion/. Curing of an epoxy compound is generally carried out in the presence of chemically equivalent amounts of the epoxy compound and the amine compound.
It is an extremely interesting phenomenon that apparent hardening can be observed even with a small amount such as 5% by weight.

The curing reaction of an uncured epoxy emulsion by piperazine or its derivative can be estimated by quantifying the amount of piperazine or its derivative remaining in water after one reaction.

That is, the epoxy group reaction rate E and the reaction rate Pt of piperazine and its derivatives are determined as follows.

Eeq fp fp-rp P= xloo fp Ic: Epoxy value θq of the epoxy compound Poq: Piperazine fC is the amine value fo of its derivative
= Charge amount of epoxy compound f, : Charge amount of piperazine or its derivative rp: Remaining amount of piperazine or its derivative after reaction Charge amount of piperazine or its derivative When fp is small, P increases but E decreases. . When E becomes small, the boxy emulsion particles will not harden sufficiently,
When P is excited, the particles stick to each other and become integrated. Amine 1 in which the amount of piperazine or its derivative charged is calculated stoichiometrically from the epoxy value of the epoxy emulsion.
This phenomenon occurs under an equivalent weight of 15 deuterons. On the other hand f
As p increases, P generally decreases, but E increases. For this reason, the harder fp is, the better the hardened particles can be obtained. However, as expected from the decrease in P, mainly for economic reasons, the amount of piperazine and its derivatives charged is 1 equivalent of amine, ioo, It is desirable that the amount is less than 0 weight molecules. The concentration of the epoxy emulsion when curing the uncured epoxy emulsion with piperazine or its derivative is not particularly limited, but it should be 5 weight molecules or more.

Preferred from the viewpoint of emulsion stability.

However, if the epoxy emulsion concentration is too high, the chances of the 9 particles coming into contact with each other will increase, making them more likely to aggregate during the curing reaction, so it is desirable that the emulsion concentration during curing be below 80 gw. In order to perform particulate hardening of an epoxy emulsion, the gist of the present invention is to use piperazine or a derivative thereof as a hardening agent, but piperazine or a derivative thereof may coexist with another water-soluble hardening agent. is also possible. Examples of curing agents that can coexist include aliphatic amines such as isopropylamine, alkylene polyamines such as ethylene diamine and diethylene triamine, alcohol amines such as ethanolamine, jetanolamine, and triethanolamine, and aliphatic tertiary amines such as triethylamine. Amines.

Aromatic amines such as benzylamine and 4-aminodiphenylamine, 44/-diaminodicyclohexylmethane, N(2-aminoethyl)piperazine, and the like. These compounds contain 15% by weight of the stoichiometric amine equivalent of piperazine or its derivative, the structure of which is shown above.
Only when these are present, they coexist to realize particulate hardening of the epoxy emulsion. In other words,
Even if piperazine ti is used alone or in combination with a water-soluble curing agent other than its derivative, particulate hardening of the epoxy emulsion will not be achieved. In other words, in order to achieve the present invention, as a water-soluble curing agent.

The above-mentioned puperazine or its derivative was used in an amount of 15 deuterons or more of the equivalent amine amount calculated stoichiometrically from the epoxy value of the epoxy emulsion.

If necessary, other water-soluble curing agents are used in combination.

Piperazine and its derivatives used in the present invention.

Since both are secondary amines, when they react with an epoxy group, that part becomes a tertiary amine. Therefore.

A tertiary amino group and a terminal secondary amine group may exist as amine groups in the epoxy fine particles after the curing reaction. These amino groups have less active hydrogen than -grade amine groups, and are clearly disadvantageous when utilizing the remaining amino groups to modify the particle surface. In this respect, as mentioned above, water-soluble amine curing agents other than perazine or its derivatives, such as polyvalent amine compounds containing primary amine groups such as diethylenetriamine, may be used in combination.

In surface modification of epoxy fine particles, the number of amino groups,
It is advantageous in terms of the number of active hydrogens.

To add a water-soluble curing agent containing piperazine or its derivatives to an epoxy emulsion, it is common to mix the curing agent directly into the emulsion, but for compounds that are solid at room temperature like piperazine, water, alcohol, A method of adding after dissolving it in a water-soluble organic solvent such as cellosolves is preferred.

When an epoxy emulsion is directly mixed with a compound that is solid at room temperature, such as piperazine, the curing agent concentration becomes locally non-uniform during the dissolution process, reducing the stability of the emulsion.
It is often experienced that uniform particles cannot be obtained. In order to avoid kneading, it is necessary to dissolve it in advance.

Further, as methods for adding the water-soluble curing agent, there are two methods: adding the entire amount at once and adding the water-soluble curing agent in small amounts continuously or intermittently. There is no particular problem in achieving the present invention using either method, but when either or both of the epoxy emulsion concentration and curing agent solution concentration are high and when a large amount of curing treatment is performed, the reaction rate and For the purpose of controlling the heat of reaction, it is recommended to add small amounts continuously or intermittently.

The reaction between the epoxy compound and the curing agent is generally an exothermic reaction. Since the reaction rate increases as the temperature rises, 9 exothermic heat is sometimes preferable in the sense of accelerating the curing speed, but when performing particulate curing of epoxy emulsions, the rise in emulsion temperature often increases the speed of curing. Decreases emulsion stability. I don't really know why, but
It is presumed that this increases the stickiness of the semi-hardened fine particles and promotes agglomeration of the emulsion particles.

For this reason, when adding piperazine or its derivatives, and if necessary, other water-soluble curing agents, to an uncured epoxy emulsion and curing it into particles, it is important to maintain the liquid temperature below 70°C for a while after adding the curing agent. is preferred. In terms of reaction operation, it is necessary to cool the reaction mixture so that the curing temperature is below this temperature, and in some cases, it is necessary to add a curing agent little by little continuously or intermittently. However, at the end of the 9 reaction, the liquid temperature can be raised to 70°C or higher in order to complete the reaction.

Furthermore, although this does not limit the present invention, when adding the curing agent, after stirring is performed to obtain a uniform mixing state of the epoxy emulsion and the curing agent, the curing conditions may be affected. Preferably, substantial agitation is limited. Excessive stirring causes the semi-hardened particles to collide, resulting in agglomeration and enlargement of the particles.

Essential stirring here does not include gentle stirring performed for the purpose of removing reaction heat, but refers to vigorous stirring for emulsification or relatively strong stirring for the purpose of chemical reaction. Among these, the most preferable condition is when the reaction conditions are close to those of standing still, and it is possible to obtain a completely cured particulate product. Typically.

When the curing agent is present in the epoxy emulsion in an amount of 50% or more, there is no particular need to restrict stirring as described above after addition of the curing agent. However, it is recommended that substantial agitation be avoided for epoxy emulsions where the curing agent is less than 50% of the amount of foil.

Epoxy fine particles are hardened and prepared into particles in two or more ways. When the hardened particles are separated from water by filtering or centrifugation, they can be recovered in powder form. Epoxy fine particles are prepared in a relatively uniform spherical form with a particle size of 1 to 50 μm, or less than 1 μm in some cases, depending on the curing conditions, but if some agglomeration occurs during curing, it becomes non-spherical and porous. It can also grow into particles.

The epoxy fine particles after curing are used in a dry state or in a state dispersed in a medium such as water or alcohol, or subjected to surface modification treatment.

Note that in the present invention, piperazine and its derivatives are used as the skeleton of the curing agent as the N-forming agent for the epoxy emulsion.

The curing reaction between a curing agent having two secondary amines in the molecule and an epoxy compound having two epoxy groups in the molecule often tends to form a chain polymer, although it depends on the curing conditions. be. Linear cured products are generally inferior to polymers with a three-dimensional crosslinked structure in terms of solvent resistance and heat resistance. To prevent this, a curing agent or a crosslinking agent is added to the epoxy compound in advance, and the resulting emulsion is then cured into particles according to the present invention.

There is a method of three-dimensional crosslinking using heat treatment or the like.

Compounds that can be added to the epoxy compound before emulsification for this purpose include the following. Particularly epoxy compound curing agents serve this purpose, examples being polyvalent amines, polyvalent secondary amines.

Acid anhydride curing agent, tertiary amine, and imidazole.

Combinations with curing accelerators such as phosphonium salts and acetylacetone metal complexes, polyphenol curing agents, polyamine curing agents, latent curing agents such as carboxylic acid hydrazides, and diaminomaleonitriles.

Examples include dicyandiamide, imidazoles, nylon salts and phosphates of polyamines, Lewis acids and their amine complexes.

Epoxy compounds that already contain these curing agents or crosslinking agents *
Because properties such as viscosity change easily depending on the pot life, it is necessary to emulse it within a relatively short time. Thereafter, according to the present invention, the emulsion is hardened into particles and heat-treated in the range of room temperature to 200°C, thereby producing epoxy fine particles with improved solvent resistance and heat resistance and high mechanical strength.

The present invention will be explained below with reference to Examples.

Example 1 A commercially available epoxy emulsion containing 65% by weight of bisphenol A diglycidyl ether (Recon ELX-25.
Epoxy value 290. Petrochemicals ■) 20g,
6g, 6g, 1.5 piperazine in 15g of water, respectively
g, 0.6 g, and 0.3 g of dissolved piperazine aqueous solution were mixed. The amount of piperazine added is 200%, ioo%, 50%, and 20%, respectively, of the amount of amine 1 calculated stoichiometrically from the epoxy value of the epoxy emulsion.
, corresponds to the io section. After stirring lightly with a spatula until uniform, the mixture was allowed to stand at room temperature and changes over time were observed.

As shown in the table below, fine epoxy particles having an average particle diameter of around 10 μm were prepared except for 10% of the amine equivalent. However, at 10% of the amine equivalent, the particles were not sufficiently cured even after 10 days, and the particles separated by filtration were bonded to each other, making redispersion impossible.

*20 Particulate hardening × Particles are not sufficiently cured immediately after joining.

Example 2 Resincon F of the epoxy emulsion used in Example 1
! LX'-2520g, piperazine 6g, water 5g, 1
Aqueous solutions of piperazine dissolved in 5 g, 50 g, 100 g, and 2'00 g were mixed. The epoxy emulsion concentration after mixing was 52% by weight.

They are 37%, 26%, 11%, and 5.9% (piperazine is excluded from the calculation), and each piperazine is 10% of the amine equivalent. After stirring the mixture lightly and uniformly using a magnetic stun, the mixture was allowed to stand at room temperature for 6 days. As the results are shown in the table below, as the epoxy emulsion concentration during curing decreased, the emulsion particles tended to agglomerate.

In all cases, cured products with beautiful spherical particles were obtained.

Example 6 Commercially available epoxy emulsion containing 65% by weight of diglycidyl ether type epoxy compound of bisphenol A (Recon KLX-30, epoxy value 340, manufactured by Vetrochemicals ■) 20g (!:, 1.5g of piperazine in 15g of water)
The dissolved aqueous piperazine solution was mixed at different temperatures. After stirring lightly and uniformly with a magnetic stun, the mixture was left standing at each temperature for 1 hour, 6 hours, and 6 hours. Subsequently, each solution was heated to 90'a, and the cured state was observed after 2 days.

As shown in the table below, the higher the initial curing temperature and the longer the heating time, the more the emulsion particles tended to aggregate, but fine spherical particles were obtained in both cases.

Example 4 Commercially available epoxy emulsion used in Examples.

Resicon ELX-4020g, 5g of water and 2 piperazine
．． 58, 1.5g, 1.0g dissolved [1, piperazine aqueous solution were mixed at room temperature. The epoxy emulsion concentrate during curing was 52% by weight (calculated excluding piperazine),
The amine equivalent is 1100%.

60%, 40 Yu. After both solutions were added, they were vigorously stirred using a magnetic stun for 6 hours. Thereafter, stirring was stopped and the mixture was allowed to stand at room temperature for 5 days to be cured.

As shown in the results in the table below, when piperazine decreases,
Although the particles were more uniform when the initial stirring was not performed vigorously, fine spherical particles were prepared in all cases.

Example 5 Commercially available bisphenol A epoxy resin (-Epicote 8
28. Epoxy value 190. Made of oil-based shell epoxy) 1
[10g of commercially available nonionic surfactant M S-230
' (manufactured by NOF ■) was mixed well.

To this, 25 g of water was added in 5 g portions with vigorous stirring to form an epoxy emulsion of about 77 parts. Add piperazine to 20g of epoxy emulsion and 1. + (2
-Aminoethyl)piperazine aqueous curing agent solutions having different composition ratios were added and gently stirred at 40°C for 2 days to harden into particles.

As shown in the following table, when the amount of piperazine was reduced, agglomeration and hardening of the particles was observed, but other than that, fine spherical particles were obtained.

Example 6 Aqueous curing agent solutions having different composition ratios of piperazine and monoethanolamine were added to 20 g of the epoxy emulsion prepared in Example 5, and the mixture was stirred to become a homogeneous solution.
It was left standing at 0°C. The hardening state after 2 days is shown in the table below. When the amount of piperazine decreases, particulate hardening occurs.
However, other than that, fine spherical particles were obtained.

Example 7 To 2°g of the epoxy emulsion prepared in Example 5,
Aqueous curing agent solutions having different composition ratios of piperazine and triethylamine were added, stirred to form a homogeneous solution, and then allowed to stand at room temperature for 6 days to harden the particles. As shown in the table below, if piperazine was used too little, the product did not harden into particles, but under other conditions, it hardened into fine particles.

*2 Weight ratio to epoxy compound weight Example 8 N, N, 'N', N' having four epoxy groups in the molecule
-Tetraglycidyl m-xylene diamine (trade name T
ETRAD-'X, epoxy value 100. Mitsubishi Gas Chemical■
2-ethylhexyl glycidyl ether (trade name: Epolite M-8110. Epoxy value: 200.
To 25 g of Kyoeisha Yushi ■) was added, 1 portion of the nonionic surfactant Neugen, KA-137 (Daiichi Kogyo Seiyaku ■゛) was added.
5g was added and kneaded well. While vigorously stirring, 50 g of water was added in five 10 g portions to obtain an emulsion of about 73 parts. This epoxy emulsion 20
to g.

Add curing agent aqueous solutions with different composition ratios of piperazine and ethylenediamine, stir until homogeneous, and then
It was allowed to stand and harden for several days.

As shown in the following table, as the amount of piperazine decreased, uniform particulate curing was less likely to occur, but otherwise fine spherical particles were obtained.

Mizuko emulsion particles Example 9 Tetrafunctional poxy compound used in Example 8, TBTRA
D-X 1004, 100 g of 1,6-hexanesiol diglycidyl ether (trade name Evolite 1'600, epoxy value 150, manufactured by Kyoeisha Yushi ■), and 10 g of Noraon surfactant MS-250 were thoroughly kneaded. Add 100g of water 20g at a time while stirring vigorously, about 6
Adjusted the epoxy emulsion in Section 8. To 100 g of this emulsion were added water/ethyl alcohol = SO15O solutions with different composition ratios of piperazine and benzylamine, stirred until uniform, and then allowed to stand at room temperature for 4 days.

As shown in the table below, as the amount of piperazine decreased, particulate hardening became less likely to occur, but fine particulate hardening was observed under other conditions.

Example 10 Commercially available epoxy emulsion KLX-2 used in Example 1
Aqueous curing agent solutions having different composition ratios of piperazine and diethylenetriamine were added to 5,100 g, stirred until uniform, and then allowed to stand at room temperature for 6 days. As shown in the following table, as the amount of piperazine decreased, uniform particle curing occurred, but otherwise fine spherical particles were obtained.

Example 11 ``Phenol, which is said to have 4 to 5 epoxy groups in the molecule, and a novolak type epoxy resin (trade name Epicoat 152, epoxy value 175, manufactured by Yuka Shell Epoxy ■) and epoxy groups in the molecule. The mixing ratio of glycidyl methacrylate (epoxy value: 145) was changed, and 5 parts by weight of the nonionic surfactant Neugen EA-137-i epoxy compound was added. Water was gradually added with vigorous stirring to prepare an emulsion weighing 65% by weight.

To this emulsion was added an aqueous piperazine solution in an amount twice the amine equivalent, and the emulsion was left standing at room temperature for 6 days.

As the results are shown in the following table, a fine particulate cured product was obtained.

Mizuko epoxy compound Example 12 Nonionic surfactant N5 = 230i was used with a different mixing ratio of Epicote 828 used in Example 5 and glycidyl methacrylate, which has 22 epoxy groups in the molecule.
Add 7 parts by weight of the epoxy compound and adjust the epoxy emulsion by 70 parts by weight. To this emulsion were added amine equivalents of piperazine and N(2-amineethyl).
Add a mixed amine aqueous solution containing piperazine to 1 ml at room temperature.
It was allowed to stand and cure for 0 days.

As the results are shown in the table below, a fine particulate cured product containing glycidyl methacrylate was obtained.

Claims (2)

[Claims] (1) Epoxy-based fine particles made of an epoxy-based resin in which piperazine or a piperazine derivative represented by the general formula of Shimane has reacted with an epoxy group, and are spherical with a particle size of 1 to 50 μm. R' (R, R' are hydrogen atoms, fc is a hydrocarbon residue having 1 to 4 carbon atoms) (2) When adding a water-soluble curing agent to an uncured epoxy resin emulsion and curing it into fine particles, piperazine or a piperazine derivative represented by the following general formula is calculated stoichiometrically from the epoxy value of the epoxy resin emulsion. A method for producing epoxy-based fine particles, characterized by using a water-soluble curing agent having a coefficient of 15 or more of the amine equivalent. R' (R, R' are hydrogen atoms or hydrocarbon residues having 1 to 4 carbon atoms)