JPH01129054A - Epoxy resin composition for application to wet surface - Google Patents

Abstract

PURPOSE:To obtain a resin composition which can be easily and uniformly applied and is good in workability in, especially, underwater application, by mixing an epoxy resin with a polyamine and a clay mineral having specified fiber diameter and fiber length. CONSTITUTION:This epoxy resin composition comprises an epoxy resin, a curing agent based on a polyamidoamine and a clay mineral having a fiber diameter of 0.01-1mu and a fiber length of 0.1-100mu. As said epoxy resin, one having an epoxy equivalent of preferably about 140-1000 is used. When the epoxy equivalent is excessively small, the properties of the obtained cured film will be impaired, while when it is excessively large, the epoxy resin tends to becomes solid. When the fiber diameter and length of said clay mineral are outside the above ranges, its dispersibility in the composition is markedly decreased, and the paint film properties after curing and the durability are adversely affected undesirably. Examples of said clay mineral included attapulgite and sepiolite.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an epoxy resin composition for applying to wet surfaces, which can be coated in a thick film, particularly in water.

<Conventional technology> In recent years, it has been used for oil drilling or oil stockpurge associated with offshore development, steel structures such as offshore blunt ships, piers of huge bridges built on the ocean, underwater steel structures for offshore airports, etc. Buildings and construction continue to increase, but it is almost impossible to move them from the installation area for maintenance. Therefore, problems such as anticorrosive coating, cleaning, and maintenance occur in the underwater parts or splash zones of these steel structures, and the need for maintenance in the sea has become a major issue. As a ninth means to solve this problem, it is considered to form a coating with excellent anti-corrosion properties on the underwater parts and splash zones of these steel structures using the same simple and easy method as on land. It will be done.

On the other hand, conventionally known underwater coating compositions include epoxy resin-based compositions.

There are compositions in which polyamide or polyamine is used as a hardening agent and a filler is added thereto. However, this composition is difficult to apply as a uniform thick film, has weak adhesion, and is extremely easily washed away by waves during curing, and even if it is cured, the adhesiveness of the cured product is insufficient and it lasts for a long period of time. Corrosion protection can hardly be expected.

In addition, such underwater-curable epoxy resin compositions can be used in still water or under simply humid conditions, even if the viscosity of the resin system and curing agent system is relatively low; In underwater or sloppy zones such as marine structures such as piers and water gates, it is particularly desirable to select and use resins and hardeners that have a high viscosity and can be made into a putty-like composition. It will be done. According to the formulation system with low viscosity, this can be achieved by mixing the two.
This is because, after inning, sealing, etc. are applied, during room-temperature curing, the material that has flowed out due to hydraulic force may peel off, resulting in a failure to form a uniformly thick film and resulting in a decrease in anticorrosive performance.

Conventionally, underwater curable epoxy resin compositions consisting of such high viscosity formulations have been mixed by automatic means such as low viscosity formulations, by mixing means using stirring jigs, or by mechanical means during coating. The construction method is usually the so-called hand work, in which the mixture is mixed by hand and the construction is carried out by hand. Particularly in the case of offshore structures that have complex structures and require work conditions that make it difficult to install permanent scaffolding, there is no choice but to rely on such hand work methods.

However, conventionally known compositions of this type have the problem that when mixing the resin system and the curing agent system, the mixture sticks to the hands and cannot be mixed sufficiently. This problem can be avoided to some extent by, for example, adding an oily substance such as petrolatum to each formulation, but in this case, the water-repellent action of the oily substance mentioned above makes it impossible to successfully adhere to the construction surface. It becomes impossible to achieve the original purpose.

Another solution is to use water as an anti-adhesion medium, focusing on the fact that underwater curing agents dissolve in water and have a property that the curing reaction is not easily affected by water. However, a wet hand method is being considered, in which the hands are constantly wet with water. However, even with this method, the following problems occur and the expected results are not obtained.

That is, even if you wet your hands with water, the water will migrate into the formulation within a short period of time, so you will have to frequently wet your hands with water during mixing. This becomes extremely inefficient in actual construction, and increases the amount of water that migrates into the compound, which may adversely affect the properties of the cured product. It is also conceivable to carry out the mixing operation itself in water as a means of constantly moistening hands with water, but deterioration of the properties of the cured product due to the contamination of a large amount of water is unavoidable.

<Problems to be Solved by the Invention> The present invention solves the above-mentioned problems of the conventional epoxy resin compositions, and allows easy mixing and construction work in a high viscosity compounding system even in the wet hand method.

The object of the present invention is to provide a new and useful epoxy resin composition for applying to wet surfaces, which can be easily coated with a uniform thick film.

Means for Solving the Problems> As a result of repeated studies to solve the above problems, the present inventors found that an epoxy resin composition containing a specific clay mineral has improved workability on wet surfaces, especially underwater. The present inventors have discovered that the present invention is excellent and that uniform thick film coating is sufficiently possible.

That is, 1. The epoxy resin composition for wet surface construction of the present invention comprises an epoxy resin, a curing agent containing polyamidoamine as a main component,
And the fiber diameter is 0.01~1μ and the fiber length is 0.1
It is characterized by containing ~100μsQ clay mineral.

Examples of the epoxy resin used in the present invention include epoxy resins that have been conventionally used for this type of paint.

An example of such an epoxy resin is the following formula.

A substituted or unsubstituted glycidyl group (for example,
Glycidyl ether, glycidyl ester.

Examples include those having at least one glycidylamine, glycidylimine, etc.) in the molecule.

Examples of such epoxy resins include diglycidyl ether of bisphenol A and diglycidyl ether of bisphenol F.

Examples include epoxy resins of phenol novolacs, diglycidyl ethers of alkylene oxide adducts of bisphenols, and the like.

The epoxy equivalent of the above epoxy resin is not particularly limited, but
Preferably, those having an epoxy equivalent of about 140 to 1000 are used. If the epoxy equivalent is too small, the properties of the cured coating film obtained will deteriorate.

On the other hand, if the size is too large, the epoxy resin tends to become solid.

In addition, it is preferable to use a material with an average epoxy group of 1.5 or more in one molecule, and by using a material with an average epoxy group of 1.5 or more, the characteristics of the cured coating film obtained can be improved. can be forced to do so.

The properties of the epoxy resin used in the present invention are 1. Usually liquid or semi-solid is used, and solid epoxy resin is n
- Can be used in liquid or semi-solid form by mixing with a diluent that can dissolve solid epoxy resins such as butyl glycidyl ether, allyl glycidyl ether, 2-ethylhexyl glycidyl ether, styrene oxide, phenyl glycidyl ether, etc. .

The curing agent for the epoxy resin used in the present invention is:

The main component is polyamide amine.

Preferably, those having an average of about 1.7 or more primary to secondary amine groups per molecule are used.

Specifically, polymerized fatty acids such as dimer acid and trimer acid obtained by polymerizing higher fatty acids having unsaturated bonds in the molecule such as liluic acid, oleic acid, linoleic acid, elaidic acid, and lysyllic acid, and polyamines, especially Condensation reaction products with aliphatic polyaquines may be mentioned.

From the viewpoint of condensation reactivity, polyamines having two or more amino groups having at least one active hydrogen atom per molecule are used as the polyamines.For example, aliphatic diamines containing no ring structure in the molecule , alkylene polyamines Polymethylene diamines having one branch, polyalkylene polyamines, aliphatic diamines containing aromatic residues in the ring structure, aliphatic diamines containing aliphatic residues in the ring structure, heterocycles Examples include aliphatic amines containing residues in the ring structure. Incidentally, these polyamines may be used alone or in combination of two or more kinds to be subjected to the condensation reaction.

Aliphatic diamines that do not contain a ring structure in their molecules include:
Examples include ethylenediamine, trimethylenediamine, tetramethylenediamine, hexamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, and undecamethylenediamine. Examples of alkylene polyamines include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, hexamethylenehebutamine, di(hexamethylene)triamine, and tri(hexamethylene)tetramine.

Examples include tet-2 (hexamethylene) pentamine, tripropylene tet-2 mi/, and tetrapropylene pentamine.

The branched tV polymethylene diamines include 2-methyl-2,4-diaminopentane.

CHg TomiHzN (CHg)n CHNH! (n: 1 or more and 8
Examples include ia).

As polyalkylene polyamines, iminobispropylamine (HxN(CHz) s NH(CHz
) s NH! ).

Methyliminobispropylamine (Hz N(CH2)
s-CHgN(CHz)sNHz), tetra(aminomethyl)methane.

Tetrakis(2-aminoethylaminomethyl)methane,
Examples include triethylene-bis(trimethylene)hexamine. Examples of aliphatic diamines containing an aromatic residue in the ring structure include 1-3-diaminomethylnaphthalene, 1,4-
Diaminomethylnaphthalene, 4,4-diaminomethylbiphenyl, 3,3-diaminomethylbiphenyl, ortho-, meta- or para-xylylenediamine (ω・ω'
-diaminoxylene).

Examples of aliphatic diamines containing an aliphatic residue in the ring structure include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, and 1,2-diamifcyclohexane. 1
-Amino-3-aminomethyl-3,5,5-trimethylcyclohexane (inphorondiamine), 1-8-diamino-8-menthane, bis-(4-aminocyclohexyl)methane, 2,2-bis-(4 -aminocyclohexyl)furopane, 1.3-bis-(aminomethyl)cyclohexane, 1.2-bis-(aminomethyl)cyclohexane, bis-(4-amino-3-methylcyclohexyl)methane, and the like. Examples of aliphatic amines containing a heterocyclic residue in the ring structure include N-aminoetherpiperazine, 1
・4-bis-(3-aminopropyl)piperazine, 3.
9-bis-(3-aminopropyl)-2-4, 8, 10
- Tetraoxaspiro(5-5) Kundecane, etc.

The most typical polyamide amines are condensation reaction products of dimer or trimer acids such as phosphoric acid and various polyamines.

Its structure is as follows when the dimer acid of riluic acid is used as a raw material, for example.

(Mountain C) 7-d-old CCkh)s Hm (In the formula, R and R' are polyamine residues.

They may be of the same species or different species. ) The above polyamide amine has an amine value of 100 to 500.
The active hydrogen equivalent is preferably in the range of t-50 to 150, and the amount of the curing agent is such that the active hydrogen equivalent of the entire curing agent is 0.5 to 2 per epoxy group of the epoxy resin.
．． It is preferable to set the amount within a range of 5 equivalents.

If the amount is less than 0.5 equivalent, curing may be insufficient, and if it exceeds 2.5 equivalents, unreacted curing agent may remain in the cured coating film and adversely affect the properties. There is.

The polyamide amine in the present invention acts as the main component of the curing agent, but a curing aid or curing accelerator can also be appropriately added as a subcomponent.

Such compounds include BFs-amine complex, hexahydrophthalic anhydride, and dicyandiamide.

Examples include imidazoles such as 2-ethyl-4-methylimidazole, triethylenetetramine, modified aliphatic polyamines, and modified aromatic polyamines.

Furthermore, chain extenders and crosslinking agents can be added, such as azelaic acid.

These include dibasic acids such as fumaric acid and dimercaptans such as 106-hexanedithiol and 18-octanedithiol. Additionally, maleic anhydride.

Acid anhydrides such as succinic anhydride, phthalic anhydride, hexahydroheptalic anhydride = 4,4-synchropentylmethylene isocyanate, 4,4-diphenylmethylene diinocyanate, 2,4-) IJ diisocyanate, 2,6 - Diisocyanates such as lylene diisocyanate and 1,4-phenylene diisocyanate: ethylenediamine, 1,2-propanediamine, 1,3-propanediamine, 1,4-buta/diamine, 2-methyl-
1,2-propanediamine, 1,5-pentanediamine, 1,6-hexenediamine, 1-7-hebutanediamine, 1,8-octanediamine, 1O-decanediamine, 1,12-dodecanediamine Aliphatic amines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, bis(hexamethylenetriamine),
Triamin.

Aliphatic polyamines such as 3,3-iminobispropylamine = 102-diaminocyclohexane.

Alicyclic diamines and polyamines such as 1,8-p-menthanediamine = 4-(aminomethyl)piperidine,
The number of carbon atoms in piperazine and each alkyl group is 1 to 12.
N-(aminoalkyl)piperazine, preferably 1 to 6 (e.g., N-(2-amineethyl)piperazine,
Heterocyclic diamines and polyamines such as N-(3-7minoprovil)piperazine, N-N-bis(3-aminopropyl)piperazine: and 1,4-dibromobutane, 1,3-dibromobutane, 1-4 -dichlorobutane, l, 2-cycloethane, l, 4-short butane,
1 to 1 carbon atom, such as 1,6-dichlorohexane
12 fatty acid dihalides, preferably with 1 carbon atom
There are ~8 aliphatic dibromides and/or dichlorides.

Other suitable and more desirable chain extenders and/or crosslinking agents include
24. In particular, there are dihydroxyaromatic compounds having 6 to 18 carbon atoms. In this compound.

Catechol, resorcinol, 3-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol, 1.
Examples include 3-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, and 1,7-dihydroxynaphthalene. Even more desirable is bisphenol represented by the following formula.

(In the formula, R is a divalent radical containing 1 to 8 atoms of at least one selected from the group consisting of C, O, S, and N, preferably an alkylene or alkylidene group having 1 to B carbon atoms, more preferably is an alkylene or alkylidene group having 1 to 6 carbon atoms.) Suitable bisphenols include methylenebisphenol,
These include inglopylidene bisphenol, butyritene bisphenol, octylidene bisphenol, bisphenol sulfide, bisphenol sulfone, bisphenol ether, and bisphenol amine.

The epoxy resin composition for application to wet surfaces of the present invention contains clay minerals having a fiber diameter of 0.01 to 1 μm and a fiber length of 0.1S to 100 μm. Such clay minerals include asbestos and non-asbestos minerals, and non-asbestos minerals include attapulgite and seviolite, which are chain-structured clay minerals.

Palygorskite and the like can be used, preferably attapulgite or sepiolite.

Note that two or more of these clay minerals may be used in combination.

If the fiber diameter and fiber length of the clay mineral are outside the above range, the dispersibility in the composition will be markedly reduced, which will have a negative effect on the coating film properties and durability after curing, so it is not preferable.

The above-mentioned clay mineral is preferably blended in an amount of 3 to 50% by weight in the total composition of the present invention! If L is less than 3% by weight, the effect of adsorbing free water during mixing or application to wet areas will be insufficient, suppressing the shrinkage phenomenon during curing and reducing residual stress generated at the adhesive interface. becomes difficult to do. As a result, the properties of the cured product tend to deteriorate and the adhesiveness tends to be poor.

In addition, when the amount exceeds 50% by weight, the consistency of the entire composition tends to be low and it becomes difficult to spread the coating during coating.

The epoxy resin composition for wet surface construction of the present invention is as follows.

Although it is composed of the following negative components, it is desirable to adjust its consistency to a range of 50 to 300 degrees, preferably 80 to 200 degrees, from the viewpoint of workability during construction and adhesion of the coating film. If the consistency is too small, the composition of the present invention will become hard and it will be difficult to spread it.4If the consistency is too large, it will become soft and the pressure applied to the object will not be sufficiently transmitted to the adhesive interface during application, making it difficult to adhere. When the strength is reduced, the uncured paint film is more likely to peel off and wash out due to water currents and waves. In addition, 1. The consistency referred to in the present invention refers to the consistency under the condition of 25℃, JISK2220
It represents the depth at which a specified cone vertically penetrates into a sample under standard conditions using a penetrometer based on 0.1 m x e1.
It is a unit.

The epoxy resin composition of the present invention may contain a seed filler as needed for the purpose of adjusting the consistency and specific gravity, improving workability, improving the mechanical strength of a cured coating film, relaxing stress, etc. It can be blended in 300 parts by weight or less. Such fillers include, for example, calcium carbonate, clay, carbon black, titanium dioxide, barium sulfate, metal powders, gates powders, glass flakes.

Examples include cement, inorganic fibers, etc., and diluents, silane coupling agents, #Agent 1 coloring pigments, antirust pigments, etc. can also be blended as appropriate.

To obtain the epoxy resin composition for wet surface construction of the present invention 1
For example, if necessary, a curing accelerator and various fillers are added to the epoxy resin, a curing agent mainly composed of polyamide amine, and a clay mineral, and the mixture is stirred.

Just mix.

<Effects of the Invention> As described above, the epoxy resin composition for applying to wet surfaces of the present invention contains a specific clay mineral in the composition made of epoxy resin, so it is possible to apply a uniform thick film, and it is possible to apply evenly on wet surfaces. It is possible to obtain a coating film that has good workability on surfaces, especially underwater construction, and has excellent cured product properties.

<Example> The present invention will be described in more detail with reference to Examples below. In addition, in the following, parts mean parts by weight.

Example 1 Bisphenol A type epoxy resin (epoxy equivalent: 190
), 100 parts of butyl glycidyl ether (epoxy equivalent: 140), 1 part of γ-glycidoxyglobyltrimethoxysilane, 80 parts of the reaction product of riluic acid dimer acid and diethylenetriamine (amine value: 31 O, active hydrogen equivalent: 125) , Merck 150 parts, titanium dioxide 5 parts, carbon black 0.5 parts, attapulgyi)
'(4mm fiber 0.05μm, fiber length 0.1μsm) 12
The mixture was mixed in a stirring mixing pot at 30° C. to obtain an epoxy resin composition having a consistency of 230.

Comparative Example 1 In Example 1, bentonite clay (montmorillonite) 50[- was added instead of attapulgite.
A composition having a consistency of 40 was obtained in the same manner as in Example 1.

Example 2 In Example 1, bisphenol A epoxy resin (epoxy equivalent: 1) was used instead of bisphenol A epoxy resin.
75) An epoxy resin composition with a consistency of 120 was obtained in the same manner as in Example 1, except that 40 parts of Seviolite (fiber diameter 0.1μ vortex, fiber length 50μ) was blended in place of attapulgite. .

Comparative Example 2 In Example 1, 30 parts of an epoxy modified product of diethylenetriamine (amine value: 770, active hydrogen equivalent: 52) was used instead of the reaction product of polyamide amine:/, and the amount of talc was changed to 100 parts. teeth.

A composition having a consistency of 150 was obtained in the same manner as in Example 1.

Example 3 An epoxy resin composition with a consistency of 50 was obtained in the same manner as in Example 1, except that Merck was not blended and attapulgite was blended i[-180 parts.

Comparative Example 3 A composition with a consistency of 390 was obtained in the same manner as in Example 1, except that attapulgium (Th) was not added.

The compositions obtained in each of the above Examples and Comparative Examples were applied to a thickness of 511 mm by a wet hand method onto a plastic steel plate vertically erected in seawater.

The composition of Comparative Example 1 could be easily formed into a uniform coating film with a thickness of 5 mm, but Comparative Example 1 was too hard and difficult to spread, and Comparative Example 2 was difficult to spread by hand. The composition of Comparative Example 3 was too soft and easily dripped, and a uniform coating film with a thickness of 5 mm could not be obtained.

In addition, the composition coated on the above steel plate was submerged in seawater.

It was cured for 7 days at 20° C., and the coating film properties after i-forming were measured by the following method. The results are shown in Table 1.

Coating film adhesion> Measured using an adhesion tester manufactured by Elcometer.

Impact resistance strength〉 According to JIS K 5400, a DuPont impact tester is used to drop a load under the conditions of a striking core diameter of 0.5 inches and a load of 5 kg, and the maximum height that reaches the steel plate without causing cracks or cracks is measured. I did◎

Claims (3)

[Claims] (1) For construction on wet surfaces characterized by containing an epoxy resin, a curing agent mainly composed of polyamide amine, and a clay mineral with a fiber diameter of 0.01 to 1 μm and a fiber length of 0.1 to 100 μm. Epoxy resin composition. (2) The epoxy resin composition for application to wet surfaces according to claim 1, wherein the clay mineral is attapulgite or sepiolite. (3) The epoxy resin composition for wet surface construction according to claim 1, which has a consistency of 50 to 300.