Epoxy resin composition, epoxy resin molded article, and method for manufacturing the molded article.

Abstract

To provide an epoxy resin composition that allows for the easy formation of molded articles with excellent creep resistance. [Solution] An epoxy resin composition containing epoxy resin (A), extender pigment (B), alkylene polyamine (C), and tertiary amine (D), satisfying the following requirement (I): (I) The creep rate, which is the rate of change in thickness before and after applying a load of 4.5 MPa at 80°C for 1,000 hours to an epoxy resin molded article formed from the epoxy resin composition, is 0.2% or less.

Description

[Technical Field]

[0001] The present invention relates to an epoxy resin composition, an epoxy resin molded article, and a method for producing the molded article. [Background technology]

[0002] The underside of the engine is filled with a material that offers excellent resistance to the load and heat of the engine's components, with the aim of enabling accurate and easy installation of the engine's constituent components. As a filler used in the lower part of such a ship engine, for example, Patent Document 1 describes a filler formed from a vibration-damping urethane resin composition. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] International Publication No. 2016 / 031825 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] When filling materials are used, especially in the underside of ship engines, they are required to have excellent creep resistance (low creep rate). On the other hand, conventional fillers, such as the filler described in Patent Document 1, had room for improvement, particularly in terms of creep resistance.

[0005] The present invention has been made in view of the above-mentioned problems, and aims to provide an epoxy resin composition that can easily form a molded article with excellent creep resistance. [Means for solving the problem]

[0006] As a result of diligent research to solve the aforementioned problems, the inventors of the present invention have found that the aforementioned problems can be solved according to the following configuration example, and have completed the present invention. An example of the configuration of the present invention is as follows.

[0007] [1] An epoxy resin composition containing an epoxy resin (A), an extender pigment (B), an alkylene polyamine (C), and a tertiary amine (D), and satisfying the following requirement (I). Requirement (I): The creep rate, which is the percentage change in thickness of an epoxy resin molded article formed from the epoxy resin composition, after being subjected to a load of 4.5 MPa at 80°C for 1,000 hours, is 0.2% or less. [2] The epoxy resin composition according to [1], wherein the viscosity at 23°C, as measured using a B-type viscometer, is 50,000 mPa·s or less. [3] The epoxy resin composition according to [1] or [2], wherein the pigment volume concentration (PVC) is 30% or more. [4] An epoxy resin composition for marine use, as described in any of [1] to [3].

[0008] [5] An epoxy resin molded article formed from any of the epoxy resin compositions described in [1] to [4]. [6] An epoxy resin molded article as described in [5], used in the main engine of a ship.

[0009] [7] A method for producing an epoxy resin molded article, comprising the step of pouring an epoxy resin composition described in any of [1] to [4] into a construction site to form an epoxy resin molded article. [Effects of the Invention]

[0010] According to the present invention, it is possible to provide an epoxy resin composition that can easily form a molded article with excellent creep resistance (creep change rate of 0.2% or less). Since such a molded article has excellent creep resistance, load-bearing capacity, and heat resistance, it can be particularly suitably used in the lower part of a ship's main engine. Moreover, according to an embodiment of the present invention, an epoxy resin composition can be provided which is a composition having a low viscosity (50,000 mPa·s or less) and can easily form a molded body having a small creep change rate.

Mode for Carrying Out the Invention

[0011] ≪Epoxy Resin Composition≫ The epoxy resin composition according to the present invention (hereinafter also referred to as "the present composition") contains an epoxy resin (A), an extender pigment (B), an alkylene polyamine (C), and a tertiary amine (D), and satisfies the following requirement (I). Requirement (I): The creep change rate, which is the change rate of the thickness before and after applying a load of 4.5 MPa for 1,000 hours at 80°C to an epoxy resin molded body formed from the present composition, is 0.2% or less.

[0012] Resin-based materials may undergo plastic deformation when a large load is continuously applied for a long time in a high-temperature atmosphere, and this is called creep change. It can be said that a molded body having a creep change rate within the above range is excellent in creep resistance, and the smaller the creep change rate, the better. In the present specification, "creep resistance" is determined by the creep change rate, and the creep change rate is specifically measured by the method described in the following examples. Since the creep change rate is a physical property related to load resistance and heat resistance from its measurement method, it can also be said that a molded body having a creep change rate within the above range and excellent in creep resistance is excellent in load resistance and heat resistance.

[0013] Materials (molded bodies) used in ships need to be evaluated in accordance with the classification rules established by a classification society. For molded bodies used in the main engine (lower part) of a ship, it is required as a design requirement that the creep change rate be 0.2% or less. Since this composition is such that the creep rate of the epoxy resin molded article formed from it is 0.2% or less, such a composition can be suitably used for marine applications, and is particularly suitable for use in the main engine (lower part) of a ship.

[0014] This composition may be a one-component composition, but is usually a two-component or more composition containing a main component containing epoxy resin (A) and a curing agent component containing alkylene polyamine (C). Furthermore, if necessary, this composition may be a multi-component composition containing a third component other than the main component and the curing agent component. These main components, curing agents, and third components are typically stored, transported, and mixed in separate containers immediately before use.

[0015] The viscosity of this composition at 23°C, as measured using a B-type viscometer, is preferably 50,000 mPa·s or less, more preferably 5,000 to 30,000 mPa·s, and even more preferably 7,000 to 20,000 mPa·s. Compositions with a viscosity within the aforementioned range are preferred because they exhibit high fluidity and are easy to form molded articles by methods such as pouring. The viscosity mentioned above refers to the viscosity when this composition is prepared (e.g., when the main component and the curing agent component are mixed).

[0016] <Epoxy resin (A)> The epoxy resin (A) is not particularly limited, and conventionally known epoxy resins can be used. Examples of epoxy resin (A) include the non-tar epoxy resins described in Japanese Patent Publication No. 11-343454 and Japanese Patent Publication No. 10-259351. The epoxy resin (A) used in this composition may be one type or two or more types.

[0017] Examples of epoxy resins (A) include polymers and oligomers containing two or more epoxy groups in one molecule, and polymers or oligomers produced by ring-opening reactions of these epoxy groups. Examples of such epoxy resins include glycidyl ether type epoxy resins, glycidyl ester type epoxy resins, glycidylamine type epoxy resins, bisphenol type epoxy resins, novolac type epoxy resins, aliphatic epoxy resins, alicyclic epoxy resins, fatty acid modified epoxy resins, and epoxidized oil-based epoxy resins. Among these, bisphenol-type epoxy resins are preferred due to their excellent mechanical strength (e.g., compressive strength and flexural strength) and high versatility, and bisphenol A-type and bisphenol F-type epoxy resins are even more preferred. In particular, it is preferable to use bisphenol A-type and bisphenol F-type epoxy resins in combination, as this allows for the easy acquisition of epoxy resin compositions with excellent fluidity.

[0018] More specifically, epoxy resin (A) may include bisphenol A type epoxy resin (bisphenol A type diglycidyl ethers); bisphenol AD ​​type epoxy resin; bisphenol F type epoxy resin; phenol novolac type epoxy resin; cresol novolac type epoxy resin; and trishydroxyphenylmethane type epoxy resin. These may also be hydrogenated products (hereinafter also referred to as "hydrogenated"), fatty acid modified products, or brominated products in which at least one hydrogen atom in the resin is replaced by a bromine atom.

[0019] Examples of the bisphenol-type epoxy resin include polymers or oligomers having a bisphenol structure within one molecule and containing two or more epoxy groups, and polymers or oligomers produced by the ring-opening reaction of the epoxy groups. Specific examples of the bisphenol A type epoxy resin include polymers of bisphenol A type diglycidyl ethers such as bisphenol A diglycidyl ether, bisphenol A (poly)propylene oxide diglycidyl ether, bisphenol A (poly)ethylene oxide diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, hydrogenated bisphenol A (poly)propylene oxide diglycidyl ether, and hydrogenated bisphenol A (poly)ethylene oxide diglycidyl ether.

[0020] The epoxy equivalent of epoxy resin (A) is preferably 150 to 1,000, and more preferably 180 to 500, from the viewpoint of curability and other factors. In this specification, epoxy equivalent refers to the epoxy equivalent of the solid content of epoxy resin (A), and is calculated based on JIS K 7236:2001.

[0021] The weight-average molecular weight of the solid content of epoxy resin (A), as measured by GPC (gel permeation chromatography), is preferably 350 to 20,000.

[0022] The viscosity of epoxy resin (A) at 25°C, as measured with an E-type viscometer (TOKIMEC, FMD type, rotation speed: 60 rpm), is preferably 1,500 to 120,000 mPa·s, and more preferably 3,000 to 30,000 mPa·s.

[0023] The solid content of epoxy resin (A) in this composition is preferably 10 to 60% by mass, more preferably 20 to 50% by mass, based on 100% by mass of the solid content of this composition, in order to easily obtain an epoxy resin composition with excellent filling properties (fluidity) and curability, and to easily form a molded article with excellent load-bearing capacity and creep resistance.

[0024] <Extender pigment (B)> The extender pigment (B) is not particularly limited, and conventionally known extender pigments can be used. The extender pigment (B) used in this composition may be one type or two or more types.

[0025] Examples of extender pigments (B) include silica, talc, mica, potassium feldspar, wollastonite, kaolin, clay, bentonite, titanium dioxide, zinc oxide, calcium carbonate, magnesium carbonate, barium sulfate, and silica sand (quartz sand mainly composed of silicon dioxide (e.g., silica sand described in JIS G 5901:2016 and JIS Z 8901:2006)). Among these, silica, talc, mica, potassium feldspar, wollastonite, kaolin, clay, calcium carbonate, and barium sulfate are preferred, and potassium feldspar, wollastonite, and calcium carbonate are particularly preferred because they have low oil absorption and allow for easy adjustment of the viscosity of the composition.

[0026] The oil absorption capacity of the extender pigment (B) is preferably 40 mL / 100 g or less, more preferably 30 mL / 100 g or less. By using an extender pigment (B) whose oil absorption amount falls within the aforementioned range, even when a large amount of the extender pigment (B) is used, it is possible to easily obtain an epoxy resin composition that is not easily thickened, has low viscosity, and excellent filling properties (fluidity). The oil absorption capacity of extender pigment (B) can be measured in accordance with JIS K 5101-13-2:2004.

[0027] The average particle size of the extender pigment (B), measured in accordance with JIS K 5101-14-1:2004, is not particularly limited, but is preferably 30 to 1,000 μm, more preferably 50 to 800 μm, from the standpoint of easily forming a molded body with excellent load-bearing capacity.

[0028] The content of the extender pigment (B) in this composition is preferably 10 to 70% by mass, more preferably 20 to 60% by mass, based on 100% by mass of the solid content of this composition, in order to easily form a molded article with excellent creep resistance.

[0029] The pigment mass concentration (PWC) in this composition is preferably 20-70%, more preferably 30-60%, from the viewpoint that it is possible to easily form molded articles with excellent creep resistance. The PWC refers to the percentage of the total mass of all pigments, including extender pigments (B), etc., relative to the mass of solids (non-volatile components) in this composition, and is represented by the following formula (1). PWC[%] = Total mass of all pigments in this composition / Mass of solids in this composition × 100 ... (1)

[0030] The pigment volume concentration (PVC) in this composition is preferably 20% or more, more preferably 25% or more, even more preferably 30% or more, preferably 60% or less, and more preferably 55% or less, from the viewpoint that it is possible to easily form a molded article with excellent creep resistance.

[0031] The PVC refers to the percentage of the total volume concentration of all pigments, including extender pigment (B), etc., relative to the volume of solids (non-volatile matter) in the composition, and is represented by the following formula (2). PVC[%] = Total volume of all pigments in this composition / Volume of solids in this composition × 100 ... (2)

[0032] In this specification, the solid content of this composition refers to the residual amount obtained by heating according to JIS K 5601-1-2:2008 (heating temperature: 125°C, heating time: 60 minutes). Alternatively, the solid content of this composition can also be calculated by excluding the amount of solvent and dispersion medium in the raw materials used. Furthermore, in this specification, the solid content of each raw material used in this composition (e.g., epoxy resin (A)) refers to the residue in each raw material other than the solvent and dispersion medium.

[0033] The volume of solids in the composition can be calculated from the mass and true density of the solids in the composition. The mass and true density of the solids may be measured values ​​or values ​​calculated from the raw materials used. The volume of the pigment can be calculated from the mass and true density of the pigment used. The mass and true density of the pigment may be measured values or values calculated from the raw materials used. For example, it can also be calculated by separating the pigment and other components from the solid content of the present composition and measuring the mass and true density of the separated pigment.

[0034] <Alkylene polyamine (C)> The alkylene polyamine (C) is a polyamine other than a tertiary amine (a polyamine having at least one primary or secondary amino group in one molecule) and is not particularly limited as long as it is a polyamine having an alkylene group, and a conventionally known alkylene polyamine can be used. As the alkylene polyamine (C), a polyamine having no oxyalkylene group is preferable. Since the present composition contains the alkylene polyamine (C) together with (A), (B) and (D), a molded body excellent in creep resistance can be easily formed. The alkylene polyamine (C) used in the present composition may be one kind or two or more kinds.

[0035] Examples of the alkylene polyamine (C) include compounds represented by the following formulas (3) to (5). H2N-R

[0035] -NH2···(3) [In formula (3), R 1 is a divalent hydrocarbon group having 1 to 12 carbon atoms.] H2N-(C m H 2m NH) n H ···(4)​​​​​​​​​​​​​`` is an alkyl group having 1 to 8 carbon atoms, and `p` is an integer from 1 to 6.

[0036] Examples of compounds represented by formula (3) include methylenediamine, ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, and trimethylhexamethylenediamine.

[0037] Examples of compounds represented by formula (4) include diethylenetriamine, dipropylenetriamine, triethylenetetramine, tripylenetetramine, tetraethylenepentamine, tetrapropylenepentamine, pentaethylenehexamine, nonaethylenedecamine, bis(hexamethylene)triamine, and triethylene-bis(trimethylene)hexamine.

[0038] Examples of compounds represented by formula (5) include dimethylaminoethylamine, diethylaminoethylamine, dibutylaminoethylamine, dimethylaminopropylamine, diethylaminopropylamine, dipropylaminopropylamine, dibutylaminopropylamine, and dimethylaminobutylamine.

[0039] As the alkylene polyamine (C), other compounds other than those represented by formulas (3) to (5) above may be used. Examples of such other compounds include tetra(aminomethyl)methane, tetrakis(2-aminoethylaminomethyl)methane, 1,3-bis(2'-aminoethylamino)propane, and N,N'-bis(3-aminopropyl)ethylenediamine.

[0040] The alkylene polyamine (C) preferably contains a compound represented by formula (4) above, in terms of being able to easily obtain an epoxy resin composition with excellent curability and easily form a molded article with excellent load-bearing capacity and creep resistance, and more preferably contains at least one selected from the group consisting of triethylenetetramine, diethylenetriamine, tetraethylenepentamine, and pentaethylenehexamine.

[0041] The active hydrogen equivalent of alkylene polyamine (C) is preferably 10 to 1,000, more preferably 20 to 400, from the viewpoint that an epoxy resin composition with excellent curability can be easily obtained, and a molded article with excellent load-bearing capacity and creep resistance can be easily formed. The value of the active hydrogen equivalent refers to the amount of active hydrogen per unit of solid content of alkylene polyamine (C).

[0042] The solid content of alkylene polyamine (C) in this composition is preferably 1 to 40% by mass, more preferably 2 to 30% by mass, based on 100% by mass of the solid content of this composition, in order to easily obtain an epoxy resin composition with excellent curability and to easily form a molded article with excellent load-bearing capacity and creep resistance.

[0043] From the standpoint of easily obtaining epoxy resin compositions with excellent curability and easily forming molded articles with excellent load-bearing capacity and creep resistance, it is desirable to use alkylene polyamine (C) in an amount such that the reaction ratio calculated by the following formula (6) is preferably 0.7 to 1.2, more preferably 0.8 to 1.1.

[0044] Reaction ratio = {(Amount of solids of alkylene polyamine (C) / Active hydrogen equivalent of the solids of alkylene polyamine (C)) + (Amount of solids of the raw material reactive with epoxy resin (A) / Functional group equivalent of the solids of the raw material reactive with epoxy resin (A))} / {(Amount of solids of epoxy resin (A) / Epoxy equivalent of the solids of epoxy resin (A)) + (Amount of solids of the raw material reactive with alkylene polyamine (C) / Functional group equivalent of the solids of the raw material reactive with alkylene polyamine (C))} ... (6)

[0045] Here, the "raw material that is reactive with alkylene polyamine (C)" in formula (6) above can be, for example, a silane coupling agent, and the "raw material that is reactive with epoxy resin (A)" can be, for example, a silane coupling agent. As the silane coupling agent, a silane coupling agent having an amino group or an epoxy group as a reactive group can be used, so it is necessary to determine whether the silane coupling agent is reactive with epoxy resin (A) or alkylene polyamine (C) depending on the type of reactive group, and to calculate the reaction ratio. The "functional group equivalent" of each of the above raw materials refers to the mass (g) per mole of functional group obtained by dividing the mass of 1 mole of solid content of these raw materials by the number of moles of functional groups contained in it.

[0046] <Tertiary amine (D)> The use of a tertiary amine (D) together with (A) to (C) in this composition is preferable because it allows for easy acquisition of an epoxy resin composition with excellent curability and easy formation of molded articles with excellent creep resistance. Examples of tertiary amines (D) include triethanolamine (N(C2H5OH)3) and dialkylaminoethanol {[CH3(CH2) nExamples include ]2NC2H5OH, n: number of repetitions}, triethylenediamine{1,4-diazabicyclo[2.2.2]octane}, and 2,4,6-tris(dimethylaminomethyl)phenol{[(CH3)2NCH2]3-C6H5OH}. As the tertiary amine (D), a compound synthesized by a conventionally known method may be used, or a commercially available product may be used. Examples of such commercially available products include Versamin EH30 (manufactured by Henkel White Water Co., Ltd.) and Ancamine K-54 (manufactured by Evonik).

[0047] The solid content of the tertiary amine in this composition is preferably 0.1 to 5% by mass, more preferably 0.5 to 3% by mass, based on 100% by mass of the solid content of this composition, in order to easily obtain an epoxy resin composition with excellent curability and to easily form a molded article with excellent creep resistance.

[0048] <Additives> The composition may further contain additives other than those described in (A) to (D) above, as long as it does not impair the purpose of the present invention. Examples of such additives include reactive diluents, other pigments other than the extender pigment (B), dispersants, rheology control agents, defoaming agents, surface modifiers (leveling agents), other curing agents other than the alkylene polyamine (C) and the tertiary amine (D), silane coupling agents, plasticizers, water, and solvents. These additives may be used individually or in combination of two or more types.

[0049] [Reactive Diluent] The reactive diluent is preferably an epoxy compound whose viscosity at 25°C, as measured by an E-type viscometer (TOKIMEC, FMD type, rotation speed: 60 rpm), is 500 mPa·s or less, and more preferably an epoxy compound having a viscosity of 500 mPa·s or less and possessing two or more glycidyl groups. Examples of the reactive diluent include 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, cyclohexanedimethanol diglycidyl ether, resorcinol diglycidyl ether, mono- or polyalkylene glycol diglycidyl ether (alkylene group with 1 to 5 carbon atoms, e.g., ethylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether), and trimethylolpropane triglycidyl ether.

[0050] If the composition contains a reactive diluent, its content is preferably 10% by mass or less, more preferably 5% by mass or less, based on 100% by mass of the solids content of the composition, and it is preferable that the composition is substantially free of reactive diluents. In this invention, "substantially free of a certain additive" means that the additive is not incorporated into the composition, for example, that the content of the additive relative to 100% by mass of the solid content of the composition is less than 0.01% by mass.

[0051] [Other Pigments] Examples of the aforementioned other pigments include coloring pigments and functional pigments. Examples of the aforementioned coloring pigments include conventionally known inorganic pigments such as carbon black, titanium dioxide (titanium white), iron oxide (red iron oxide), yellow iron oxide, and ultramarine, as well as organic pigments such as phthalocyanine blue and phthalocyanine green.

[0052] If this composition contains a coloring pigment, its content is preferably 0.01 to 3% by mass, and more preferably 0.01 to 2% by mass, based on 100% by mass of the solid content of this composition.

[0053] [Dispersant] The aforementioned dispersant is not particularly limited, but it is preferable that it is a dispersant that can uniformly disperse the pigments and the like in the composition and prepare a stable dispersion. Examples of the aforementioned dispersants include various known organic (e.g., aliphatic amines or organic acids) or inorganic dispersants.

[0054] If the composition contains a dispersant, its content is preferably 0.1 to 5% by mass, more preferably 0.2 to 3% by mass, based on 100% by mass of the solid content of the composition.

[0055] [Rheology control agent] The rheology control agent (also called a settling inhibitor or thixotrope) is not particularly limited, but it is preferably a material that can suppress the settling of pigments and the like in the composition and improve its storage stability. As the rheology control agent, conventionally known rheology control agents can be used, such as organic clay waxes including stearate salts, lecithin salts, and alkyl sulfonates of Al, Ca, and Zn; polyethylene wax; amide wax; hydrogenated castor oil wax; mixtures of hydrogenated castor oil wax and amide wax; synthetic fine silica powder; oxidized polyethylene wax; mineral clay viscosity modifiers; urethane association viscosity modifiers; acrylic acid viscosity modifiers; and cellulose viscosity modifiers.

[0056] If the composition contains a rheology control agent, its content is preferably 0.05 to 5% by mass, more preferably 0.1 to 3% by mass, based on 100% by mass of the solid content of the composition.

[0057] [Antifoaming agent] It is preferable that the composition and the molded articles obtained from it are free of air bubbles, as this allows for the easy formation of molded articles with excellent load-bearing capacity. For this reason, it is preferable to incorporate an antifoaming agent into the composition. Examples of such defoaming agents include silicone-based defoaming agents and mineral oil-based defoaming agents, each of which is available in water-based, solvent-based, and solvent-free forms. Among these, solvent-free silicone-based defoamers are preferred in order to suppress shrinkage during the formation of the molded product.

[0058] If the composition contains an antifoaming agent, its content is preferably 0.3 to 5% by mass, and more preferably 0.5 to 3% by mass, based on 100% by mass of the composition.

[0059] [Other hardening agents] Examples of other curing agents include polyoxyalkylene (poly)amines. In one embodiment of this composition, alkylene polyamine (C) and polyoxyalkylene (poly)amine may be used in combination.

[0060] Examples of polyoxyalkylene (poly)amines include the compounds represented by the following structural formulas (7) and (8).

[0061] [ka] [In formula (7), R 1 R is a hydrogen atom, a methyl group, an ethyl group, a propyl group, or a t-butyl group. 2 R is independently an ethylene group, a 1,2-propylene group, a 2,3-propylene group, or a 1,3-propylene group. 3 [where n is a methylene group, ethylene group, 1,2-propylene group, 2,3-propylene group, or 1,3-propylene group, and n represents the average value of the repeating units, ranging from 2 to 100.]

[0062] [ka]

[0063] In formula (8), R 1 , R 2 , and R 3 Each of these is independently an alkylene group having 1 to 10 carbon atoms, preferably an alkylene group having 1 to 5 carbon atoms, and more preferably an alkylene group having 2 carbon atoms. One or more hydrogen atoms bonded to the alkylene group may be substituted with a hydrocarbon group having 1 to 10 carbon atoms, and the number of carbon atoms in the substituted hydrocarbon group is preferably 1 to 5, more preferably 1. In formula (8), R 1 , R 2 , and R 3 Each of these is preferably independently -CH2-CH2-, -CH2-CH(CH3)-, or -CH(CH3)-CH2-. n represents the average value of the repeating units, and is between 1 and 100, preferably between 1 and 30, and more preferably between 1 and 10.

[0064] The weight-average molecular weight (Mw) of the polyoxyalkylene (poly)amine is preferably 100 to 5,000, more preferably 200 to 1,500, from the viewpoint that this composition, which has excellent storage stability, can be easily obtained.

[0065] As the polyoxyalkylene (poly)amine, commercially available products may be used. Examples of such commercially available products include "Jeffermin M-600" (weight-average molecular weight: 600), "Jeffermin M-1000" (weight-average molecular weight: 1,000), "Jeffermin M-2005" (weight-average molecular weight: 2,000), "Jeffermin M-2070" (weight-average molecular weight: 2,000), "Jeffermin D-230" (weight-average molecular weight: 230), and "Jeffermin D-400" (weight-average molecular weight: 430) (all manufactured by Huntsman).

[0066] If the composition contains other curing agents, the amount is preferably such that it satisfies the reaction ratio, and more preferably 1 to 40% by mass, and more preferably 2 to 30% by mass, based on 100% by mass of the composition.

[0067] <Method for preparing this composition> This composition, or the main component, curing agent component, etc., can be prepared by mixing (kneading) the aforementioned raw materials. During this mixing (kneading), the raw materials may be added and mixed all at once, or they may be added and mixed in multiple stages. During the mixing (kneading) process, conventionally known devices such as mixers, dispersers, and agitators can be used. Examples of such devices include dispersers, mixing / dispersing mills, mortar mixers, rolls, paint shakers, and homogenizers. Furthermore, the mixing (kneading) process may be carried out with heating, cooling, etc., depending on the season, environment, etc.

[0068] If air is incorporated during the preparation of the main component or when mixing the main component with the curing agent component, air bubbles may remain in the resulting molded product, potentially causing cracks and other problems. Therefore, it is preferable to reduce the amount of air incorporated into the composition by performing a degassing process during the preparation of the main component or the composition, or by stirring at a low rotation speed when mixing the main component with the curing agent component.

[0069] ≪Epoxy resin molded product≫ The epoxy resin molded article according to the present invention (hereinafter also referred to as "the molded article") is formed from the composition described above.

[0070] This molded product exhibits excellent creep resistance. Therefore, this molded product can be suitably used in equipment that generates vibration, such as ships, automobiles, railways, aircraft, buildings, industrial equipment, home appliances, and precision instruments. Among these, it is particularly suitable for use in high-temperature environments, such as around engines, especially marine engines (including main engines and auxiliary engines). This molded body is particularly suitable for use in the lower part of a marine engine, and in the case of a marine engine equipped with a main engine and auxiliary engines, it can be used especially well in the main engine (lower part).

[0071] [Creep change rate] The creep rate, which is the percentage change in thickness of this molded body before and after applying a load of 4.5 MPa at 80°C for 1,000 hours, should be 0.2% or less; the smaller the creep rate, the better. A molded body whose creep rate falls within the aforementioned range can be said to have excellent creep resistance and is particularly suitable for use in the lower part of a ship's main engine. The creep rate can be measured specifically by the method described in the following examples.

[0072] Specifically, this molded body can be formed by, for example, pouring, extrusion, injection molding, or RIM molding of this composition. Alternatively, it can be formed by, for example, applying this composition to the area where the molded body is to be formed (hereinafter also referred to as the "construction area") using a spray, roller, or brush, and allowing it to harden. Among these, this composition has excellent filling properties (fluidity), so it is preferable to pour this composition directly into the application area and allow it to harden to form the molded body. This method is preferable because it allows the molded body to be formed directly in the desired location and also allows the molded body to sufficiently fill even narrow gaps. When forming the molded body by pouring, a mold or the like may be used as necessary to prevent the composition from flowing out from the desired location. [Examples]

[0073] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples. In the following description, unless otherwise specified, "parts by mass" will be written as "parts".

[0074] [Example 1] In a container, 39 parts epoxy resin A1, 4.2 parts epoxy resin A2, 43 parts extender pigment B1, 3 parts extender pigment B3, 9.2 parts extender pigment B5, 0.1 parts coloring pigment 1, 0.5 parts dispersant, 0.2 parts rheology control agent, and 0.8 parts defoaming agent 1 were placed and mixed using a high-speed disperser to prepare the main component. In a separate container, 7 parts alkylene polyamine C1 and 2 parts tertiary amine D1 were placed and mixed using a high-speed disperser to prepare the curing agent component. The prepared main component and curing agent component were mixed and degassed to prepare an epoxy resin composition.

[0075] [Examples 2-4 and Comparative Examples 1-10] An epoxy resin composition was prepared in the same manner as in Example 1, except that each component listed in Table 1 was used in the values ​​(amount, parts by mass) listed in the table. Table 2 shows a description of each component listed in Table 1.

[0076] <pwc> The pigment mass concentration (PWC) in the prepared epoxy resin composition was calculated based on formula (1) above. The results are shown in Table 1.

[0077] <pvc> The pigment volume concentration (PVC) in the prepared epoxy resin composition was calculated based on formula (2) above. The results are shown in Table 1.

[0078] <Viscosity> The viscosity of the prepared epoxy resin composition at 23°C was measured using a Type B viscometer (Model: BII viscometer, manufactured by Toki Sangyo Co., Ltd.) with a No. 4 rotor. The results are shown in Table 1.

[0079] <Creep change rate> The epoxy resin compositions obtained in Examples 1-4 and Comparative Examples 1-10 were degassed, and the degassed epoxy resin compositions were poured into a 100 × 100 × 12.7 mm mold and cured at 23°C for 16 hours to obtain epoxy resin molded articles. The prepared molded articles were cured in accordance with ASTM D 621. After curing, test specimens approximately 12.7 mm in size per side were cut from the molded articles. Using a creep tester (manufactured by Yasuda Seisakusho Co., Ltd., No. 145-B-3), a load of 4.5 MPa was applied in the thickness direction of the test specimens for 1,000 hours under an atmosphere of 80°C, and the thickness of the test specimens before and after the load was applied was measured. The creep change rate was calculated based on the following formula. The results are shown in Table 1. A creep rate of 0.2% or less is considered to indicate a low creep rate and excellent creep resistance. Creep rate (%) = {(Initial thickness of the specimen (before testing) - Thickness of the specimen after 1,000 hours) / Initial thickness of the specimen (before testing)} × 100

[0080] [Table 1]

[0081] [Table 2] < / pvc> < / pwc>

Claims

1. An epoxy resin composition containing an epoxy resin (A), an extender pigment (B), an alkylene polyamine (C), and a tertiary amine (D), and satisfying the following requirement (I). Requirement (I): The creep rate, which is the percentage change in thickness of an epoxy resin molded article formed from the epoxy resin composition, after applying a load of 4.5 MPa at 80°C for 1,000 hours, is 0.2% or less.

2. The epoxy resin composition according to claim 1, wherein the viscosity at 23°C, as measured using a B-type viscometer, is 50,000 mPa·s or less.

3. The epoxy resin composition according to claim 1, wherein the pigment volume concentration (PVC) is 30% or more.

4. The epoxy resin composition according to claim 1, for use in ships.

5. An epoxy resin molded article formed from the epoxy resin composition according to any one of claims 1 to 4.

6. An epoxy resin molded article according to claim 5, used in the main engine of a ship.

7. A method for producing an epoxy resin molded article, comprising the step of pouring the epoxy resin composition according to any one of claims 1 to 4 into a work site to form an epoxy resin molded article.

Images