JPH05209109A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain an epoxy resin composition having low viscosity, excellent workability, improved adhesivity to cured materials and slight change of weight with time comprising an epoxy resin, a nucleus-substituted alkylbenzyl alcohol of a specific structure and a curing agent. CONSTITUTION:An epoxy resin composition comprising (A) an epoxy resin, preferably a bisphenol A type epoxy resin liquid at 30 deg.C, (B) a nucleus- substituted alkylbenzyl alcohol (p-methylbenzyl alcohol and/or p-ethylbenzyl alcohol) of the formula (R is 1-3C alkyl), (C) a curing agent (e.g. m- xylylenediamine or ethylenediamine), 1-50 pts.wt. diluent (e.g. phenylxylylethane or benzyl alcohol) based on 100 pts.wt. total amounts of the components A and C and optionally a filler, pigment, a plasticizer, etc. The composition is widely useful in the field of civil engineering and construction field for casting and spreading floor covering material, resin mortar, grout material, adhesive, etc., for the purpose of beauty, dust prevention, corrosion prevention, etc.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an epoxy resin composition. More specifically, the present invention relates to an epoxy resin composition that can be widely used in the field of civil engineering and construction, such as cast floor material, resin mortar, grout material, and adhesive for the purpose of beauty, dust prevention, and corrosion prevention.

[0002]

2. Description of the Related Art Epoxy resins are adhesive to various substrates,
Since it has many excellent properties, such as heat resistance, chemical resistance, electrical properties, and mechanical properties, compared to other resins, it is used in the above wide industrial fields. In recent years, it has been actively used especially in the paint field. Generally, the form of the epoxy resin composition used in the field of paints and adhesives is a liquid type that does not use a solvent, a liquid type that uses an organic solvent as a main medium, a liquid type that uses water as a medium, and a solid (powder). ) It is roughly divided into types.

Organic solvent types are generally xylene, toluene,
It is used by dissolving a solid epoxy resin having a large molecular weight at room temperature and using a low-viscosity solvent such as cellosolve, ethanol, and n-butanol, and has a wide selection of curing agents. In addition to giving a cured product with excellent performance, the viscosity of the composition can be adjusted arbitrarily, so it is often used in the above-mentioned applications, but in general, an organic solvent with a large viscosity reducing effect has a high vapor pressure and is flammable There are drawbacks such as harmfulness to people, danger of environmental pollution, fire and explosion.

In recent years, there has been a strong demand for development of an epoxy resin system capable of exhibiting the original excellent characteristics without using such an organic solvent. As a means for solving this problem, efforts have been made to develop a so-called water-dilutable epoxy resin system that uses water instead of an organic solvent. However, an epoxy resin composition using water as a medium has no danger of using an organic solvent and is excellent in workability, but in many cases, it is an emulsifier or the like to disperse the epoxy resin as a main component in water. The use of dispersants is unavoidable. Therefore, there may be a problem that the water resistance and the chemical resistance of the cured product are lowered.

On the other hand, the solution type which does not use a solvent uses a curing agent having a bottom viscosity in an epoxy resin which is liquid at room temperature, and
It is used as a composition having a high boiling point, that is, a so-called diluent to reduce the viscosity of the system. Well-known diluents include aromatic hydrocarbons such as phenylxylylethane, ethylbiphenyl and dixylylmethane, and high boiling point alcohols such as benzyl alcohol and furfuryl alcohol.

[0006]

The present invention solves the above problems,
A novel method that does not lose the characteristics of a so-called solventless epoxy resin composition that uses a diluent and improves the thinning of the cured product due to the volatilization of the diluent from the cured product and the reduction of the adhesion to the substrate. An object of the present invention is to provide a novel epoxy resin composition.

[0007]

Means for Solving the Problems As a result of intensive investigations, the present inventors have found that a nucleus-substituted alkylbenzyl alcohol of a specific structure
It was found that the above-mentioned problems of the prior art can be solved by compounding the epoxy resin with the epoxy resin composition, and the present invention has been completed. That is, the present invention is an epoxy resin (A),
Nuclear-substituted alkylbenzyl alcohol represented by the following chemical formula 2
The invention relates to an epoxy resin composition comprising (B) and a curing agent (C).

[0008]

The nucleus-substituted alkylbenzyl alcohol (B) which can be used in the present invention is represented by Chemical formula 2, and as the alkylbenzyl alcohol, paramethylbenzyl alcohol and paraethylbenzyl alcohol are used. Can be illustrated. The epoxy resin (A) used in the present invention is a so-called bisphenol A type epoxy resin obtained by the reaction of bisphenol A and epichlorohydrin, or bisphenol A obtained by the reaction of bisphenol F and epichlorohydrin. Examples thereof include F-type epoxy resin and bisphenol AD-type epoxy resin obtained by the reaction of bisphenol AD and epichlorohydrin.
Among these, the epoxy resin which is liquid at 30 ° C. is preferable. If the epoxy resin used is liquid at 30 ° C., the amount of diluent added is small, which is a feature.

The curing agent (C) used in the present invention is not particularly limited, but is a known amine compound and / or derivative of an amine compound generally used for room temperature curing. Examples of preferable amine compounds include metaxylylenediamine, paraxylylenediamine, 1,3-bis (aminomethyl) cyclohexane, isophoronediamine, ethylenediamine, diethylenetriamine and triethylenetetramine. The diluent used in the present invention can be added to either side of the curing agent and the epoxy resin as the main agent, but it is preferable to add the diluent before mixing the curing agent and the main agent. The ratio of addition depends on the purpose of use and the intended use of the composition. Basically, it is determined in consideration of the properties of the cured product, but the total amount of the curing agent and the main epoxy resin is 100
In the range of 1 to 50 parts by weight, preferably 5 parts by weight.
Used in the range of up to 50 parts by weight. In addition, the epoxy resin composition of the present invention, known fillers, pigments, plasticizers,
A leveling agent, a defoaming agent, etc. can be made to coexist.
The contents of the present invention will be specifically described below with reference to examples.

【Example】

Example 1 Polycondensation product of metaxylylenediamine and epichlorohydrin (trade name: gascamine 32 manufactured by Mitsubishi Gas Chemical Co., Inc.)
8. Viscosity: 9800 mPa.S (25 ° C)) 70 parts by weight, 30 parts by weight of paraethylbenzyl alcohol was added, and the mixture was stirred with a dissolver for 10 minutes to obtain a curing agent having a viscosity of 1060 mPa.S (25 ° C). Got Bisphenol A type liquid epoxy resin (Yukaka Shell Epoxy Co., Ltd., trade name: Epitote 828, epoxy equivalent: 185) 41 parts by weight of the above curing agent was added to 100 parts by weight, and after stirring, # 240 sandpaper A cold-rolled steel sheet treated with-was coated with a doctor blade having a thickness of 100 µm and left standing at 23 ° C and 50% RH for 7 days to obtain a cured coating film. The pencil hardness of the cured coating film was H and the Erichsen cupping was 9 mm or more, and the curability and adhesion were good.

Example 2 In Example 1, paramethylbenzyl alcohol was used in place of paraethylbenzyl alcohol, and the mixture was heated to about 60 ° C. when the paramethylbenzyl alcohol and the main agent were mixed. In the same manner as in Example 1, a curing agent was prepared, a cured coating film was prepared, and the physical properties of the coating film were measured. The viscosity of the curing agent is 1140 mPa.S (25 ° C), and the pencil hardness of the cured coating is
H and Erichsen cupping were 9 mm or more, and both curability and adhesion were good.

Comparative Example 1 In place of the gascamine 328 added with para-ethylbenzyl alcohol in Example 1, gascamine 328 alone was added in an amount of 2 per 100 parts by weight of the epoxy resin.
A cured coating film was prepared and physical properties of the coating film were measured in the same manner as in Example 1 except that the amount was 8.9 parts by weight. The pencil hardness of the cured coating is B and Erichsen cupping is 9 mm or more,
The adhesiveness was good, but the viscosity was higher than in Example 1, coating was difficult, and the hardness of the cured coating film was low.

Comparative Example 2 Preparation of a curing agent, preparation of a cured coating film, and measurement of coating film physical properties were carried out in the same manner as in Example 1 except that benzyl alcohol was used instead of paraethylbenzyl alcohol. I went. The viscosity of the curing agent is 1040 mPa.S (25 ° C), the pencil hardness of the cured coating is H, and the Erichsen cupping is 6.5 mm.
The curability was good, and the adhesion was inferior to that of Example 1.

Example 3 An epoxy resin composition was prepared in the same manner as in Example 1, and then sufficiently defoamed under reduced pressure. On the other hand, a polyester film was set on a glass plate having a size of 30 × 30 cm to prepare one, and the epoxy resin composition prepared above was applied thereto, and then a spacer having a thickness of 100 μm was set on the periphery. Cover with polyester film, then 30 × 3
A glass plate having a size of 0 cm was placed on the glass plate and left at 23 ° C. for 7 days to obtain a cured epoxy resin film. The obtained epoxy resin film was cut into a size of 3 × 3 cm, weighed, and then heat-treated in a hot air dryer at 50 ° C. for 144 hours. After the heat treatment, the weight of the film was measured,
No weight loss was observed.

Example 4 The weight loss on heating of a cured epoxy resin film was measured in the same manner as in Example 3 except that the epoxy resin composition was prepared according to Example 2. As a result, the weight loss rate of the film is 0.
It was 4% by weight.

Comparative Example 3 The loss on heating of the cured film was measured in the same manner as in Example 3 except that the epoxy resin composition was prepared according to Comparative Example 2. As a result, the weight loss rate of the film is 0.62% by weight.
The value was larger than that in Example 3.

[0018]

[Effect] The epoxy resin composition of the present invention is free from various problems as in the conventional solution type epoxy resin composition, has a low viscosity, is excellent in workability, is excellent in adhesion of a cured product, and has a weight with time. It is an epoxy resin composition with little change.

Claims (4)

[Claims] 1. An epoxy resin (A), a nucleus-substituted alkylbenzyl alcohol (B) represented by the following general formula, and a curing agent.
An epoxy resin composition comprising (C). 2. The epoxy resin composition according to claim 1, wherein the epoxy resin is a bisphenol A type epoxy resin. 3. A bisphenol A type epoxy resin is 30.
The epoxy resin composition according to claim 2, wherein the epoxy resin composition is liquid at 0 ° C. 4. The epoxy resin composition according to claim 1, wherein the nucleus-substituted alkylbenzyl alcohol is paramethylbenzyl alcohol and / or paraethylbenzyl alcohol.