JP2006131786A - Resin composition for waterproofing and waterproof metal product using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition for waterproofing excellent in waterproofness, and metal products using it. <P>SOLUTION: This resin composition for waterproofing comprises (A) a thermosetting resin, (B) a layered clay mineral, (C) an inorganic ion exchanger, (D) a silane coupling agent and (E) a hardener. This composition is coated on the surface of a metal member such as a steel material singly or reinforced with a fiber. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a waterproof resin composition that protects the surface of a metal product from corrosion due to contact with moisture, and a waterproof metal product using the same.

  In heavy electrical equipment such as generators, rotating electrical machines, transformer / distribution equipment, special energy equipment, etc., because the equipment is large, large capacity, high voltage, high energy, electrical conduction, generation of magnetism, operation of the device mechanism, etc. The energy loss that occurs in the device is large, and the temperature rise of the equipment that occurs with this loss also becomes large.

  Normally, such a temperature rise is dealt with by improving the heat resistance of the insulating material. However, if such a measure is difficult, air cooling with air or hydrogen, or water cooling with water or the like is used. The equipment is cooling.

  However, in the case of water cooling, there is a problem of rusting due to contact between equipment and moisture.

Conventionally, in order to prevent rusting on the surface of such water-cooled equipment, a chemical solution such as a rust inhibitor is added to the cooling water (Patent Document 1), or a film thickness of 0.5 on the surface of the metal material on the equipment surface. A synthetic resin coating of about ˜3 mm is provided (Patent Document 2).
JP 2000-220800 A Japanese Patent Laid-Open No. 10-160090

  The method of adding a rust inhibitor to the cooling water described in Patent Document 1 uses a chemical pump to periodically inject a chemical solution by a predetermined amount. There is a problem that it takes time to make adjustments to prevent liquid leakage at the connecting portion of the chemical solution pipe in the state.

  Moreover, the method of coating the surface of the metal material described in Patent Document 2 with a synthetic resin has a problem that if the coating is thick with the synthetic resin coating, the heat conduction of the portion coated with the synthetic resin deteriorates and the cooling efficiency decreases. is there.

  Although it is conceivable to reduce the thickness of the synthetic resin coating, there is a problem that when the thickness is reduced, moisture diffuses and penetrates into the synthetic resin and reaches the surface of the metal product for a long period of time, and the metal product surface rusts. Furthermore, rusting on the metal surface occurs due to chlorine ions and metal ions in the moisture that comes into contact, but the conventional methods for preventing rusting with synthetic resin coating take into consideration the point of suppressing the movement of these ions. Therefore, there is a problem that the thickness of the synthetic resin coating cannot be reduced and cooling efficiency by water cooling is low because of the necessity of preventing rusting.

  The present invention has been made to solve such conventional problems, and an object of the present invention is to provide a waterproof resin composition excellent in rust prevention effect and a waterproof metal product using the same.

  The waterproof metal product of the present invention is not limited to a product sold as a single unit, but also includes parts constituting such a product.

  The waterproof resin composition of the present invention comprises (A) a thermosetting resin, (B) a layered clay mineral, (C) an inorganic ion exchanger, (D) a silane coupling agent, and (E) a curing agent. It is characterized by containing.

  Examples of the thermosetting resin (A) include epoxy resins and unsaturated polyester resins that have fluidity at room temperature or by heating.

  The epoxy resin used as the thermosetting resin (A) contains two or more epoxy groups which are three-membered rings composed of two carbon atoms and one oxygen atom in one molecule.

  Examples of such epoxy resins include bisphenol A type epoxy resins, brominated bisphenol A type epoxy resins, biphenyl type epoxy resins, naphthalene obtained by condensation of polychlorophenols such as epichlorohydrin and bisphenols and polyhydric alcohols. -Type epoxy resin, ortho-cresol novolac-type epoxy resin, glycidyl ether-type epoxy resin, glycidyl ester-type epoxy resin obtained by condensation of epichlorohydrin and carboxylic acid, obtained by reaction of triglycidyl isocyanate or epichlorohydrin and hydantoins Examples thereof include heterocyclic epoxy resins such as hydantoin type epoxy resins. In the present invention, these can be used alone or as a mixture of two or more.

As the curing agent (E) for the epoxy resin, for example, an amine curing agent is suitable. The amine-based curing agent is composed of a compound in which hydrogen of ammonia (molecular formula NH ₃ ) is substituted with a hydrocarbon, and has one or more amino groups in one molecule. As an epoxy resin curing agent, an acid anhydride-based curing agent is also known, but the bond network formed in the epoxy resin cured with an acid anhydride-based curing agent is an ester bond, or An amine-based curing agent is suitable for the present invention from the viewpoint of water resistance because it is composed of an ester bond and an ether bond, which may cause hydrolysis. Specific examples of the amine-based curing agent include ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, hexamethylenediamine, trimethylhexamethylenediamine, polymethylenediamine such as polyetherdiamine, mensendiamine (MDA), isophorone. Examples include diamine (IPDA), metaxylylenediamine, metaphenylenediamine, and diaminodiphenylmethane.

  The unsaturated polyester resin used as the thermosetting resin (A) generally contains an α-β unsaturated polybasic acid or an acid anhydride thereof and a polybasic acid in combination with a saturated polybasic acid as a modifying acid. It is used as a liquid resin in which an unsaturated polyester obtained by esterification with a monohydric alcohol is dissolved in a monomer that also serves as a crosslinking agent. In particular, when isophthalic acid or orthophthalic acid is used as the saturated polybasic acid, a resin cured product having excellent water resistance can be obtained because ester bonds in the resin cured product can be reduced.

  An organic peroxide is suitable as the curing agent (E) for the unsaturated polyester resin. The organic peroxide is obtained by replacing one or two hydrogen atoms of hydrogen peroxide (HOOH) with an alkyl group, an allyl group, an acyl group, or the like. Specific examples of organic peroxides suitable for room temperature curing include, for example, ketone peroxides such as methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, acetylacetone peroxide, acetoacetate peroxide, cyclohexanone peroxide, and methylcyclohexanone peroxide. Is mentioned.

  Examples of the layered clay mineral (B) include at least one selected from a smectite group, a mica group, a vermiculite group, and a mica group. Examples of the layered clay minerals belonging to the smectite group include montmorillonite, hectorite, saponite, sauconite, beidellite, stevensite, nontronite, etc., and the layered clay minerals belonging to the mica group include chlorite, phlogopite, lepidrite, Muscovite, biotite, paragonite, margarite, teniolite, tetrasilicic mica, etc. are listed, and layered clay minerals belonging to the vermiculite group include trioctahedral vermiculite, dioctahedral vermiculite, Examples of layered clay minerals include muscovite, biotite, paragonite, levitrite, margarite, clintonite, and anandite. The dispersibility in the epoxy resin is particularly excellent in the layered clay mineral belonging to the smectite group. The layered clay mineral (B) is swollen (intercalated) by incorporating various substances by an ion exchange reaction between layers. In the present invention, a material containing a quaternary ammonium ion between layers is suitable. Layered clay minerals containing quaternary ammonium ions between the layers have a good familiarity with thermosetting resins and have a large gap between layers, so that they are easily dispersed in the resin. Such a layered clay mineral intercalated with quaternary ammonium ions can be produced, for example, as follows.

  That is, after the layered clay mineral is immersed and swollen in a solution in which the quaternary ammonium compound is dissolved in water or an organic solvent, the mixture is stirred for 1 to 12 hours while being heated to 50 to 90 ° C. as necessary. After replacing the metal ions between the layers of the clay mineral with quaternary ammonium ions, the solid content obtained can be filtered, washed with water and alcohol, and dried (Japanese Patent Laid-Open No. 4). -74708). Examples of the quaternary ammonium ions intercalated in the layered clay mineral include monoalkylammonium ions, dialkylammonium ions, trialkylammonium ions, and tetraalkylammonium ions. The quaternary ammonium ion suitable for the layered clay mineral of the present invention is a tetraalkylammonium ion such as tetramethylammonium ion, tetraethylammonium ion, tetrapropylammonium ion, tetrabutylammonium ion, and particularly preferred is at least A tetraalkylammonium ion having one long-chain alkyl group, for example, a cetyltrimethylammonium ion or a tetra n-decylammonium ion. The shape of the layered clay mineral is preferably in the form of powder or fine particles from the viewpoint of dispersibility in the resin. In the present invention, the layered clay mineral acts to suppress moisture that is dispersed in the thermosetting resin with a particle size of nm units and penetrates into the cured resin. In a resin composition in which an inorganic filler having an average particle size of μm is dispersed, it is difficult to impregnate and cast a minute gap, but the resin composition of the present invention using a layered clay mineral Then, it is possible to impregnate or cast into such a minute gap.

  Examples of the inorganic ion exchanger (C) include inorganic ion exchange materials having —OH groups in their constituent components. The inorganic ion exchanger is composed of, for example, a polyvalent metal acid, a salt thereof, a polyvalent metal hydrated oxide, and the like, and specifically, an anion exchanger such as aluminum, zirconium, magnesium-aluminum, Examples thereof include cation exchangers such as zirconium and titanium, and amphoteric ion exchangers such as calcium. The inorganic ion exchanger adsorbs chlorine ions, metal ions, and the like that penetrate into the resin together with moisture and cause rust. Inorganic ion exchangers are finer than resinous organic ion exchangers, so they are excellent in dispersibility and can be highly effective even in small amounts. Moreover, heat resistance and environmental resistance other than water (for example, radiation resistance) Also excellent.

  Examples of the silane coupling agent (D) include vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, aminopropyltrimethoxy. Examples include silane, N-phenylaminopropylmethyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and γ-mercaptopropyltrimethoxysilane.

  If the interface between the resin cured product and the surface of the metal product is peeled off to form a void, water that has penetrated into the resin cured product may gather at the part and rust may be generated on the external metal surface. Since the adhesiveness between the surface of the metal product and the resin cured product is increased by the blending of the ring agent, the generation of such voids is prevented and the rusting of the metal surface is prevented.

  In the present invention, an antifoaming agent can be further added in addition to the components (A) to (E) described above. Specific examples of antifoaming agents that can be used in the present invention include lower alcohols, higher alcohols, oils and fats, fatty acids, fatty acid esters, phosphate esters, metal soaps, mineral oils, and the like. Examples thereof include foaming agents, polyether-based, and silicone-based polymer antifoaming agents. These antifoaming agents suppress the generation of voids in the thermosetting resin, shorten the impregnation time, increase the work efficiency, and improve the waterproofness of the cured resin.

  Moreover, you may mix | blend a hardening accelerator, antiseptic | preservative, a pigment, etc. in the waterproofing resin composition of this invention in the range which does not inhibit the effect of this invention.

Next, the composition of the waterproof resin composition of the present invention will be described.
The waterproof resin composition of the present invention includes, for example, 0.5 to 5 parts by weight of the layered clay mineral (B) and inorganic ions (C) with respect to 100 parts by weight of the thermosetting resin (A). It is produced by uniformly mixing 1 to 10 parts by weight of the exchanger, the silane coupling agent (D) and the effective amount of the curing agent (E) by a conventional method.

  When the blending amount of the layered clay mineral (B) is less than 0.5 parts by weight, the effect of suppressing water penetration cannot be sufficiently exerted. Conversely, when the amount exceeds 5 parts by weight, the viscosity increases. Work such as impregnation and casting becomes difficult.

  When the blending amount of the inorganic ion exchanger of (C) is less than 1 part by weight, the ion component scavenging ability is low. Conversely, when it exceeds 10 parts by weight, the viscosity of the blend is the same as in the case of the layered clay mineral. As a result, the workability is lowered.

  The total amount of the layered clay mineral (B) and the ion exchanger (C) is preferably 13 parts by weight or less.

  The waterproof resin composition of the present invention is coated on the metal product in contact with water by painting, spraying, or any other known method. At that time, if necessary, the viscosity may be reduced by heating, or it may be dissolved in an organic solvent and coated in a solution state.

  The waterproof resin composition coated on a metal product undergoes a curing reaction even at room temperature, but may be heated as necessary to promote the curing reaction. When the waterproof layer is formed at room temperature, there is no generation of thermal stress due to the difference in coefficient of linear expansion between the metal product and the waterproof resin composition, thus preventing the waterproof layer from peeling or cracking from the metal product. be able to.

  Further, the waterproof resin composition of the present invention has a glass cloth disposed on the surface of the metal product without being coated on the surface of the metal product alone, and the glass cloth is impregnated with the waterproof resin composition and cured to form a glass. It can also be a fiber-reinforced waterproof layer. In this way, by impregnating the glass cloth with the waterproof resin composition and curing it, the waterproof layer is reinforced and cracks are prevented from being generated, and durability and product quality can be stabilized.

  Since the waterproof resin composition of the present invention is blended with a layered clay mineral and an inorganic ion exchanger, it is excellent in waterproofness and scavenging of ions that cause rusting, and a silane coupling agent is blended into a metal product. It also has excellent adhesiveness and can maintain high water tightness over a long period of time.

  Moreover, since the waterproof metal composition of the present invention has a high watertight performance, the waterproof metal product of the present invention can have a thinner coating thickness than that of the conventional one, and thus can obtain high cooling efficiency. .

  Hereinafter, specific examples of the present invention and evaluation results thereof will be described. In the following examples and comparative examples, “parts” means “parts by weight”.

Example 1
100 parts of an epoxy resin (made by Japan Epoxy Resin Co., Ltd., trade name: Epicoat 828) and 3 parts of a layered clay mineral (Coop Chemical Co., trade name: STN) in which quaternary ammonium ions are intercalated between layers , 4 parts of inorganic ion exchanger (trade name: IXE, manufactured by Toagosei Co., Ltd.) and 1 part of silane coupling agent (trade name: A187, manufactured by Nihon Unicar Co., Ltd.) were added, and a three-roll mill mixer (Inoue Manufacturing Co., Ltd.) Manufactured and trade name: S-4 3/4 × 11) was passed 10 times or more and kneaded.

  Ethylenediamine (Degussa Japan Co., Ltd., 19.2 parts IPD and Sun Techno Chemical Co., D230, 6 parts) was added to the above kneaded product and mixed to prepare a waterproof resin composition.

  Next, a glass cloth (T glass cloth) was placed on the surface of the iron piece, impregnated with the obtained waterproof resin composition, and cured at room temperature to obtain a test piece.

Example 2
In Example 1, a test piece was prepared in the same manner as in Example 1 except that 0.1 part of an antifoaming agent (manufactured by Toshiba GE Silicone Co., Ltd., TSA720) was added to the components of the waterproofing composition.

Comparative Example 1
In Example 1, a test piece was prepared in the same manner as in Example 1 except that the inorganic ion exchanger and the silane coupling agent were not blended.

Comparative Example 2
In Example 1, a test piece was prepared in the same manner as in Example 1 except that the layered clay mineral having a quaternary ammonium ion inserted between the layers and a silane coupling agent were not blended.

Comparative Example 3
In Example 1, a test piece was prepared in the same manner as in Example 1 except that no silane coupling agent was added.

Comparative Example 4
In Example 1, a test piece was prepared in the same manner as in Example 1 except that the layered clay mineral in which the quaternary ammonium ion was inserted between the layers and the inorganic ion exchanger were not blended.

Next, the test piece coated with the resin composition according to the production process of Examples 1 and 2 and Comparative Examples 1 to 4 was immersed in a container containing tap water for one month, and the occurrence of rust was tested. The results are shown in Table 1.

  As is clear from the test results shown in Table 1, in Examples 1 and 2, no rust was generated, whereas in Comparative Examples 1 to 4, peeling and rust were generated.

  The waterproof resin composition of the present invention can be applied to the formation of waterproof coatings in various applications. In particular, it is suitable for waterproof coating of various industrial heavy electrical equipment and electrical / electronic equipment having a water-cooled structure in accordance with recent miniaturization, large capacity, and high voltage.

Claims (7)

  Waterproofing characterized by containing (A) thermosetting resin, (B) layered clay mineral, (C) inorganic ion exchanger, (D) silane coupling agent, and (E) curing agent. Resin composition.   (B) 0.5 to 5 parts by weight of layered clay mineral and (C) 1 to 10 parts by weight of inorganic ion exchanger are added to 100 parts by weight of thermosetting resin (A). The waterproof resin composition according to claim 1.   The waterproofing resin composition according to claim 1 or 2, wherein an antifoaming agent is blended.   The resin composition for waterproofing according to any one of claims 1 to 3, wherein the thermosetting resin (A) is an epoxy resin, and the curing agent (E) is an amine-based curing agent. .   The waterproof clay according to any one of claims 1 to 4, wherein the layered clay mineral (B) comprises at least one selected from the group of minerals consisting of a smectite group, a mica group, and a vermiculite group. Resin composition.   A waterproof metal product, wherein at least a part of the surface of the metal product is coated with a cured product of the waterproof resin composition according to any one of claims 1 to 5.   At least a part of the surface of the metal product is coated with a cured fiber reinforced resin impregnated in a fiber base material containing the waterproof resin composition according to any one of claims 1 to 5. Features waterproof metal products.