JPH0566404B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Field of Application> The present invention relates to a two-component mixed epoxy resin composition and an anticorrosive construction method using the same, and more specifically, it can be applied underwater or under humid conditions, particularly in the underwater parts, tidal zones, and splash zones of various marine structures. A two-component mixed type epoxy resin that can be used in underwater construction with excellent adhesiveness, flexibility, and corrosion resistance, and can be effectively used as paints, adhesives, sealants, etc. even under water flow and water pressure conditions. The present invention relates to a composition. <Prior Art> In recent years, development and utilization of marine resources, marine energy, and marine space have become active, and many marine structures such as port facilities, seawall facilities, marine bridges, and offshore platforms have been constructed. In general, marine structures are exposed to significantly more severe corrosive environments than land-based structures, and moreover, it is difficult to carry out regular maintenance and management, so there is a need for a corrosion protection system that can guarantee long-term corrosion protection performance. On the other hand, epoxy resins have excellent adhesive properties, water resistance, chemical resistance, mechanical properties, electrical properties, etc., so they have been widely used as various paints, adhesives, sealants, lining materials, etc. Particularly in the field of civil engineering and construction, humid conditions in the presence of water are common working conditions, so materials that can be used even under such conditions are desired, and various underwater-curable epoxy resin compositions have been developed. It's here. However, since such underwater curable epoxy resin compositions generally use a hydrophilic underwater curable curing agent, there is a problem of environmental pollution in that the curing agent dissolves into water. In addition, such underwater curable epoxy resin compositions have relatively good workability and adhesive properties in still water or under simply humid conditions, but they can be used in underwater parts of marine structures, fluctuations in water level, and tidal conditions. Satisfactory work cannot be carried out in places where there is water flow or water pressure, such as tidal areas or splash zones exposed to seawater spray, and the product may peel off due to hydraulic force during work or curing. However, it had the disadvantage that it could leak out or partially melt and fall apart. Furthermore, even if the construction is well-done, the hardened film is hard and cannot keep up with the distortion and deformation of the structure caused by impact from waves, floating objects, collisions with ships, etc., and for a very short period of time. Problems such as scratching, peeling, and rusting occur over time. For this reason, various attempts have been made to impart flexibility to resin compositions. For example, addition of various plasticity and flexibility imparting agents, mixing of flexible plastics or rubbers, monomers and prepolymers having highly reactive functional groups such as hydroxyl groups, carboxylic acid groups, and isocyanate groups. A method has been proposed in which a modified epoxy resin obtained by reacting an epoxy resin is used alone or in combination with an unmodified epoxy resin. However, these methods do not provide sufficient flexibility. Another problem is that flexibility gradually decreases over time. Furthermore, imparting flexibility through modification causes problems such as the viscosity of the epoxy resin becoming significantly high, resulting in poor workability and decreased water resistance. Furthermore, in addition to the sudden accidents mentioned above, corrosion and deterioration caused by seawater itself and pollutants (acids, alkalis, salts, etc.) in industrial wastewater, domestic wastewater, etc. that are discharged into seawater over a long period of time. There are also problems, and the resin composition is required to have high anticorrosion performance. <Problems to be Solved by the Present Invention> As is clear from the above, what is particularly desired today is a structure that has good workability for marine structures, especially workability in the ocean, and a mechanical construction. This is an epoxy resin composition that provides a coating film with high strength and corrosion resistance. The present inventor has developed a two-component mixed epoxy resin composition consisting of an epoxy resin modified with a polysulfide having a thiol group at the end and a polyamine, and the initial adhesion of the polyphosphate and the epoxy resin composition to the object. The present invention was completed by discovering that the desired objective could be achieved by blending with a special admixture for increasing the temperature. That is, the present invention provides an epoxy resin component (A) mainly composed of a polysulfide-modified epoxy resin obtained by reacting a long-chain aliphatic polysulfide compound having a thiol group at the molecular end with an epoxy resin, and a primary and/or Or a curing agent component whose main component is a poorly water-soluble liquid polyamine compound having an average of 1.5 or more secondary amino groups per molecule.
(B), and at least one of component (A) and component (B), dimer acid (C-1), liquid rubber (C-1) having at least two carboxylic acid groups in one molecule.
-2), contains at least one admixture component (C) selected from mixtures of polyoxyalkylene alkylaryl ether and amine salts of aliphatic carboxylic acids (C-3), and polyphosphate (D) The present invention discloses a two-component mixed epoxy resin composition characterized by the following characteristics: and a method for corrosion-proofing marine structures in which the composition is applied to an object underwater. To explain the present invention in more detail, examples of the long-chain aliphatic polysulfide compound having a thiol group at the molecular end, which is a raw material for the polysulfide-modified epoxy resin that is one of the components of the composition according to the present invention, include the following: Something like this is used. (1) Formaldehyde-dichloromethylal, formaldehyde-β-dichlorodiethyl acetal, formaldehyde-chloromethyl-β-
Chlorethyl acetal, acetaldehyde
Dichloro-methylal, acetaldehyde-β
- Polysulfide compounds obtained by the reaction of dichlorinated acetals such as dichlorodiethyl acetal and polysulfide sodium compounds such as sodium tetrasulfide (2) 1,2-dichloroethane, 1,2-dichloropropane, Polysulfide compounds obtained by the reaction of dichlorinated paraffins such as 1,3-dichloropropane and polysulfide sodium compounds such as sodium tetrasulfide (3) 1,1'-dichlorodimethyl ether, 2,
Polysulfide compounds obtained by the reaction of dichlorinated ethers such as 2'-dichlorodiethyl ether and 1-chloromethyl-2-chloroethyl ether with polysulfide sodium compounds such as sodium tetrasulfide (4) Butadiene, Polysulfide compounds obtained by the reaction of diolefins such as isoprene with dimercaptan compounds such as ethylene dithioglycol and propylene dithioglycol (5) Polysulfide compounds obtained by oxidation of dimercaptan compounds (6) A mixture of polysulfide compounds obtained by or a polysulfide compound obtained by co-reaction.The molecular weight of the polysulfide compound is 300 to 300.
20,000, particularly preferably in the range of 400 to 10,000. As the epoxy resin, which is the other raw material for the polysulfide-modified epoxy resin, polyepoxide having 1.7 or more epoxy groups per molecule is usually used. For example, bisphenol A
Preferred examples include epoxy resins obtained from bisphenols such as and bisphenol F and epichlorohydrin, and epoxy resins obtained from hydrogenated bisphenols such as hydrogenated bisphenol A and epichlorohydrin. Other useful polyepoxides include (1) polyglycidyl ethers of novolac resins and similar polyphenols, (2) polyglycidyl ethers of polyhydric alcohols such as ethylene glycol, propylene glycol, diethylene glycol, and glycerin; (3) Glycidyl esters of dicarboxylic acids such as phthalic acid and hydrogenated phthalic acid; (4) copolymers of (meth)acrylic acid derivatives having epoxy groups such as glycidyl acrylate and glycidyl methacrylate; (5) diolefins such as polybutadiene. Examples include epoxidized polymers. Two or more of these epoxy resins may be used in combination.
Among these epoxy resins, especially those with a viscosity of 1000
It is preferable to use a liquid at room temperature below Poise, but there is no problem even if it is solid at room temperature as long as it can be dissolved in a reactive or non-reactive diluent and handled in a fluid state at room temperature. . The modification reaction of an epoxy resin with a long-chain aliphatic polysulfide compound having a thiol group at the molecular end is carried out by heating a mixture of the two at a temperature of room temperature to 180°C, preferably 50 to 150°C, without a catalyst or with the addition of a catalyst.
This can be easily achieved by heating and stirring. As a catalyst, tertiary amine, quaternary amine salt,
Compounds such as imidazole compounds, phosphoric acid or phosphite esters, alkali metals, alkali carbonates, Lewis acids, etc. are used. As for the mixing ratio of the polysulfide compound and the epoxy resin during the modification reaction, it is desirable that the ratio of thiol group/epoxy group is in the range of 0.05 to 0.95, preferably 0.1 to 0.8. If it exceeds 0.95, the reactant will solidify or gel, resulting in a polysulfide-modified epoxy resin with significantly fewer epoxy groups. Resin compositions containing such modified products as epoxy components are difficult to cure sufficiently when applied in water. Also, if the mixing ratio is less than 0.05,
You can't get the flexibility you need. As long as the final amount of thiol component is within this range, an unmodified epoxy resin can be used in combination with a polysulfide modified epoxy resin. Furthermore, if desired, urethane-modified epoxy resins, silicone-modified epoxy resins, etc. can be mixed and used. In the present invention, the poorly water-soluble liquid polyamine compound (B) having an average of 1.5 or more primary and/or secondary amino groups per molecule has a solubility in water of 3 g or less at room temperature (100 c.c. of water). If used, aromatic polyamines such as phenylene diamine and m-tolylene diamine, which have the ability to replace water molecules, Hiker ATBN (trade name, Ube Industries, Ltd. product)
Examples include curing agents for epoxy resins such as various liquid rubbers that have diamines at both ends, as typified by: In addition, the polyamine compounds listed above and easily water-soluble polyalkylenes such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, tetramethylenediamine, hexamethylenediamine, dibutylaminopropylamine, bis-(hexamethylene)triamine, etc. By reacting an aliphatic polyamine having an aromatic ring such as polyamine or m-xylene diamine with a di-polyepoxy compound such as a monoepoxy compound such as butyl glycidyl ether or phenyl glycidyl ether or a bisphenol type epoxy resin. The amine adduct produced is also a useful poorly water-soluble polyamine compound. In addition, a monoamine compound may be partially contained in the above-mentioned polyamine compound. For example, aromatic diamines partially amidated with unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, linoleic acid, and ricinoleic acid may also be used. Further, various curing accelerators such as aliphatic polyamines, alicyclic polyamines, and tertiary amines, which are known as curing agents for room temperature curing, can be used in combination as long as they do not impair the poor water solubility. The curing agent component (B) may be an amine compound having a primary or secondary amino group, as long as it has an average of 1.5 or more of these amino groups per molecule. The curing agent component (B), which is composed of a poorly water-soluble polyamine compound or a poorly water-soluble polyamine compound and other curing agents for epoxy resins as mentioned above, is an epoxy resin component of the epoxy resin component (A) whose main component is a polysulfide-modified epoxy resin. Usually 0.5 to 2.5 equivalents of active hydrogen are added to the amino group of the amine compound per equivalent of the group.
It is preferably used in a range of 0.8 to 1.5 equivalents.
If the amount used is less than 0.5 equivalent, the composition will not be sufficiently cured and the intended purpose will not be achieved. On the other hand, if the amount exceeds 2.5 equivalents, the cured product will be in a somewhat cured state, but the cured product will be extremely brittle, have extremely low mechanical properties, and have high water absorption, causing problems. Dimer acid (C-1), which is an admixture component of the composition according to the present invention, liquid rubber (C-2) having at least two carboxylic acid groups in one molecule, or polyoxyalkylene alkylaryl ether and resin carboxyl Mixture of acid with amine salt (C-3)
is blended for the purpose of increasing initial adhesion to the substrate of marine structures and increasing resistance to peeling force of waves. Dimer acid (C-1) is a compound with 36 carbon atoms obtained by dimerizing linoleic acid or linoleic acid by Diels-Alder reaction, and is a compound with 36 carbon atoms obtained by dimerizing linoleic acid or linoleic acid. It is also possible to use a polymerized fatty acid containing as a main component a dimer acid having 36 carbon atoms. The liquid rubber (C-2) having two or more carboxylic acid groups in one molecule is a homopolymer of diene compounds such as butadiene, isoprene, chloroprene, or styrene,
Any copolymer made by copolymerizing a monomer copolymerizable with a diene compound such as acrylonitrile and having two or more carboxylic acid groups in the molecule or at the end of the molecule and is liquid at room temperature can be used, but CTB (carboxylic acid-terminated polybutadiene) and CTBN (carboxylic acid-terminated butadiene-acrylonitrile copolymer) are preferably used. A mixture of polyoxyalkylene alkylaryl ether and amine salt of aliphatic carboxylic acid (C-3- is represented by the general formula (In the formula, R represents an alkyl group having 1 to 12 carbon atoms, m and n are 0 or integer numbers of 1 or more, and m and n are not 0 at the same time) and a polyoxyalkylene alkylaryl ether represented by the general formula (In the formula, R ₁ and R ₂ are hydrogen atoms or have 1 to 1 carbon atoms.
12 alkyl groups, R ₃ represents an alkyl group having 1 to 24 carbon atoms, and X represents a saturated monocarboxylic acid having 1 to 20 carbon atoms. ) A mixture of an aliphatic carboxylic acid and an amine salt is used. This product is commercially available as, for example, a machine/metal cleaning agent or an antirust oil additive. A typical commercially available product is Clink (trade name) manufactured by Yoshimura Yukagaku Co., Ltd. The mixing ratio of polyoxyalkylene alkylaryl ether and carboxylic acid amine salt is usually 1:9 to 9:1 in molar ratio.
The ratio is preferably about 1:1. Moreover, the molecular weight is usually in the range of 200 to 1000. These admixture components may be used alone,
Alternatively, they may be used in combination. The amount used is in the range of 0.5 to 20%, preferably 1 to 10% by weight per total amount of epoxy resin component (A) and curing agent component (B).
is within the range of If the amount used is less than 0.5%, the initial adhesive strength to marine structures will be too low, and resistance to the peeling force of waves will not be sufficiently exhibited. If the amount used exceeds 20%, the initial adhesive strength will be obtained, but the curability of the epoxy resin composition will be low, and the physical properties of the cured product will be poor, and the original purpose of preventing corrosion of marine structures will not be achieved. I can't perform to my full potential. Examples of the polyphosphate (D) include dehydrated phosphates such as tripolyphosphate, monohydrogen tripolyphosphate, and dihydrogen tripolyphosphate produced by heating and dehydrating phosphate, and preferably aluminum salt or zinc salt. Salt is used. These may be used in combination if desired. Polyphosphate is contained in epoxy resin compositions as a rust-preventing pigment, and is said to be non-toxic and superior in corrosion resistance compared to conventionally used lead-, iron-, and chromium-based pigments. It is unique in that it is difficult to dissolve in water during construction, and even if it does dissolve, it will not pollute the environment. The amount of polyphosphate used is the epoxy resin component (A)
0.5-20% by weight per total amount of hardener component (B)
It is desirable to use it in a range of 1 to 10%, preferably in a range of 1 to 10%. If the amount used is less than 0.5%, sufficient rust prevention performance will not be achieved. If the amount is more than 20%, the anticorrosive power will be extremely high, but the physical properties of the epoxy resin composition after curing will deteriorate, which is not preferable. The epoxy resin composition of the present invention has the above-mentioned components A to D as main components, but in addition to these components, various organic compounds known as reactive diluents and non-reactive diluents, silica, etc. , alumina, talc, calcium carbonate, asbestos,
titanium oxide, carbon black, glass beads,
Fillers such as short glass fibers and metal powders, reinforcing agents, extender pigments, colored dyes and pigments, thixotropic agents, anti-settling agents, anti-sagging agents, silane coupling agents, titanate coupling agents, zirconium coupling agents, chelating agents , antifoaming agents, color separation inhibitors, thermoplastic resins, thermosetting resins, rubbers, etc. can be blended. The epoxy resin composition according to the present invention is a two-component mixture consisting of an epoxy resin component (A) and a curing agent component (B). The admixture component (C) and the polyphosphate (D) are
It can be mixed into either one component or both components as appropriate. Of course, the components may be mixed at the time of use if desired. The epoxy resin composition according to the present invention obtained in this way can be applied to an object in water using a brush, roller, trowel, or applicator, or made of rubber or plastic material, and can be formed into a shape or sheet that immediately corresponds to the shape of the surface to be protected. A method of applying the anticorrosive material to a corrosion-protective material molded into a material and adhering it to the surface to be protected in water, a method of impregnating various non-woven fabrics or fabrics and wrapping it around the surface to be
It can be applied using a variety of methods, such as wrapping it with FRP, rubber, or plastic and injecting it into the gap between the surface to be protected and the so-called wet hand method. It has the advantage that it can be effectively used as a material for agents, sealants, lining materials, etc. Of course, it can be used as an anticorrosion material that exhibits extremely good workability and adhesion even under non-wet conditions such as in land structures. When the epoxy resin composition according to the present invention is used in water, it is used substantially without diluting with an organic solvent so as not to pollute the environment.
When used on land, it can be diluted with an appropriate solvent to make it easier to handle. EXAMPLES The present invention will be explained in more detail with reference to Examples and Comparisons below, but the present invention is not limited to these Examples. Note that "parts" and "%" in the examples are based on weight unless otherwise specified. Example 1 Diglycidyl ether type epoxy resin of bisphenol A (epoxy equivalent: 185, viscosity: 13000 cps/
25℃, Dainippon Shikizai Kogyo Co., Ltd. Priepo PE-10)
54 parts, butyl glycidyl ether 6 parts, thiol group-terminated polysulfide having the following structural formula HS- _CH2 - _CH2 -O-CH2 _- O- _CH2 - _CH2
(-S-S -CH ₂ -CH ₂ -O-CH ₂ -O-CH ₂ -CH ₂ )-
₅ SH (average molecular weight 1000, viscosity 1100 cps/25℃, SH content 6.5%, Thiokol LP- manufactured by Toray Thiokol Co., Ltd.)
3) 40 parts were charged into a reaction vessel, the temperature was raised to 90°C, and 0.03 part of 2,4,6-tri-(dimethylaminomethyl)phenol was added while stirring. The reaction temperature was maintained at 90° C. and the reaction was continued for 3 hours with stirring to obtain a polysulfide-modified epoxy resin in the form of a yellow-brown transparent liquid with a viscosity of 170 poise/25° C. and an epoxy equivalent of 452. The polysulfide-modified epoxy resin obtained here was blended with other components in the proportions shown in the main component column of Table 1, and kneaded and mixed in a three-roll mill to prepare a main component. Similarly, a curing agent was prepared using a three-roll mill according to the formulation shown in the column of curing agent components in Table 1. The main agent and curing agent are thoroughly mixed in a predetermined weight ratio, applied to a steel plate that has been sanded in seawater to a film thickness of 150μ using an applicator, and cured for 7 days at 23°C while immersed in seawater. I let it happen. The test method is as follows: (1) Punching resistance Immediately after applying the coating to a steel plate in seawater, the seawater is stirred at high speed near the surface using a dissolver to generate strong water currents and splashes, and the presence or absence of peeling of the coating film from the steel plate is determined. (that is, the quality of initial adhesion) was observed. (2) Crosshatch rust resistance After hardening, an X-shaped cut is made in the coating film with a razor blade that reaches all the way to the steel plate surface, and the film is immersed in fresh seawater heated to 40°C for one month to prevent rust from forming. The progress of rust from the X-shaped notch was also observed. (3) Adhesive strength Glue mild steel plates together in seawater and
C. After curing for 7 days, adhesion was tested at a test speed of 5 mm/min. (4) Tensile elongation at break, Shore D hardness Tests were conducted using dumbbell-shaped specimens that were cast in seawater and cured (23°C, 7 days). The test speed was 5 mm/min. (5) Other tests were conducted in accordance with general test methods for paints. Comparative Examples 1 to 3 The same formulation as in Example 1 except that the polysulfide-modified epoxy resin was replaced with an unmodified epoxy resin or a urethane-modified epoxy resin, and polyoxyalkylene alkylaryl ether and aliphatic A formulation using hydrophilic polyamide amine was prepared and tested in the same manner as in the example except for the amine salt mixture of carboxylic acid. The test results are shown in Table 1.

【table】

[Table] Examples 2 to 4, Comparative Examples 4 to 5 Using the polysulfide-modified epoxy resin synthesized in Example 1, a base resin having the composition shown in the base component column of Table 2 was prepared in the same manner as in Example 1. A curing agent having the composition shown in the curing agent component was prepared, and the same test as in Example 1 was conducted. Example 5 Using the compositions of Examples 1 to 3 and the compositions of Comparative Examples 3 to 5, a re-corrosion prevention construction test was conducted on aged steel sheet piles of port facilities. A frame-treated polyolefin resin sheet coated with the composition on land was attached underwater to the surface of the steel sheet pile from which marine organisms and rust had been removed by underwater sandblasting, and as a result, the composition of the comparative example hardened. By then the sheet had peeled off. Good adhesion was achieved with the compositions of the examples, and no problems were observed even after 3 times.

【table】

【table】

Claims (1)

[Scope of Claims] 1. An epoxy resin component (A) whose main component is a polysulfide-modified epoxy resin obtained by reacting a long-chain aliphatic polysulfide compound having a thiol group at the end of the molecule with an epoxy resin; and/or secondary amino groups per molecule
and a hardening agent component (B) mainly composed of a poorly water-soluble liquid polyamine compound having 1.5 or more polyamines, and at least one of component (A) and component (B) contains dimer acid (C-1), At least one selected from a liquid rubber having at least two carboxylic acid groups in one molecule (C-2), a mixture of polyoxyalkylene alkylaryl ether and an amine salt of an aliphatic carboxylic acid (C-3) A two-component mixed epoxy resin composition characterized by containing a seed admixture component (C) and a polyphosphate (D). (2) The epoxy resin composition according to claim 1, wherein the polyphosphate (D) is an aluminum and/or zinc salt of polyphosphoric acid. 3 The polysulfide-modified epoxy resin consists of a polysulfide compound with a molecular weight of 400 to 10,000 and an epoxy resin with a thiol group/epoxy group ratio of 0.1.
2. The epoxy resin composition according to claim 1 or 2, which is obtained by reacting at a concentration of 0.8 to 0.8. 4 Claims 1 to 4, characterized in that the ratio of the epoxy group of the epoxy resin component (A) to the active hydrogen of the amino group of the curing agent component (active hydrogen/epoxy group) is 0.8 to 1.5. The epoxy resin composition according to any one of Item 3. 5 Claims characterized in that the admixture component (C) and polyphosphate (D) are each contained in an amount of 1 to 10% based on the total amount of the epoxy resin component (A) and the curing agent component (B). The epoxy resin composition according to any one of Items 1 to 4. 6 Epoxy resin component (A) mainly composed of a polysulfide-modified epoxy resin obtained by reacting a long-chain aliphatic polysulfide compound having a thiol group at the molecular end with an epoxy resin, primary and/or secondary amino Average group per molecule
A curing agent component whose main component is a poorly water-soluble liquid polyamine compound or its derivative having 1.5 or more polyamines.
(B), dimer acid (C-1), liquid rubber having at least two carboxylic acid groups in one molecule (C-2),
Mixture of polyoxyalkylene alkylaryl ether and amine salt of aliphatic carboxylic acid (C-
3) at least one admixture component (C) selected from
An anticorrosive construction method characterized by applying a two-component mixed epoxy resin composition consisting of a polyphosphate (D) and a polyphosphate (D) to an object in water. 7. The anticorrosion construction method according to claim 6, wherein the object is a steel marine structure. 8. The anticorrosion construction method according to claim 6 or 7, wherein the epoxy resin composition does not substantially contain an organic solvent.