JP2005336412A - Foamable epoxy resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a foamed epoxy resin molded article with high open cell rate, excellent in compression set. <P>SOLUTION: The foamable epoxy resin composition (E) comprises (A) a polyepoxide, (B) a hardener for epoxy resin and (C) at least one organic hollow filler selected from a group comprising following (C1), (C2) and (C3) as essential component. The molded article (D) is obtained by forming the foamable epoxy resin composition (E). (C1): An organic hollow filler comprising a vinyl monomer having a functional group (f1) and a vinyl monomer (g3) having a cyano group as essential constituting unit of a shell. (C2): An organic hollow filler comprising a vinyl monomer having a functional group (f2) which reacts with the functional group (f1) and the vinyl monomer (g3) as essential constituting unit of a shell. (C3): An organic hollow filler comprising the vinyl monomer (g1), the vinyl monomer (g2) and the vinyl monomer (g3) as the essential constituting unit of a shell. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a foamed epoxy resin composition and a molded product using the same. More specifically, the present invention relates to a foamed epoxy resin composition having a high open cell ratio and excellent compression set, and a molded product using the same.

  It is known that an epoxy resin foam using an organic hollow filler is useful because it has a relatively uniform cell diameter and can retain resin physical properties. For example, it is used as an epoxy placement agent for model materials (see Patent Document 1).

JP2002-220489

However, the epoxy resin foam using the above organic hollow beads usually has a problem that it cannot be used for building materials such as metal siding because it has a low open cell ratio and is inferior in compression set.
An object of the present invention is to provide a foamed epoxy resin molded article having a high open cell ratio and excellent compression set.

The inventors of the present invention have arrived at the present invention as a result of intensive studies to solve the above problems.
That is, the present invention essentially comprises a polyepoxide (A), an epoxy resin curing agent (B), and at least one organic hollow filler (C) selected from the group consisting of the following (C1), (C2) and (C3). A foamed epoxy resin composition (E) characterized by being a component.
(C1): Organic hollow filler (C2) having a functional group (f1) -containing vinyl monomer (g1) and a cyano group-containing vinyl monomer (g3) as essential constituent units of the shell: a functional group that reacts with the functional group (f1) The vinyl monomer (g2) having (f2) and the organic hollow filler (C3) comprising the vinyl monomer (g3) as an essential constituent unit of the shell: the vinyl monomer (g1), the vinyl monomer (g2), and the vinyl monomer ( an organic hollow filler having g3) as an essential constituent unit of the shell; and a foamed epoxy resin molded product (D) formed by molding the organic hollow filler.

  The foamed epoxy resin molding obtained by molding the foamed epoxy resin composition of the present invention has a very high open cell ratio and is excellent in compression set.

  The foamed epoxy resin composition (E) of the present invention comprises a polyepoxide (A), an epoxy resin curing agent (B), and an organic hollow filler (C). (C) is preferably a true specific gravity of 0.01 or more and 0.3 or less.

  Examples of the polyepoxide (A) include epihalohydrin (such as epichlorohydrin) or dihalohydrin (such as glycerin dichlorohydrin), and polyhydric (2 to 6 or more valent) phenols (bisphenol A, bisphenol). F, 1,1-bis (4-hydroxyphenyl) ethane, resorcinol, hydroquinone and catechol, and their nuclear substitutes, halogen compounds, etc.]; or multivalent (2 to 6 or more valences of 2 to 100 carbon atoms); ) Alcohol (alkane polyol (ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, trimethylolpropane, glycerin, pentaerythritol, etc.), polyalkylene having a number average molecular weight of 3000 or less (a A polyglycidyl ether obtained by reaction with 2 to 4 carbon atoms of glycols (diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, etc.); or epihalohydrin or dihalohydrin and 6 to 20 carbon atoms or more 2-6 or higher aliphatic or aromatic polycarboxylic acids (oxalic acid, fumaric acid, maleic acid, succinic acid, glutaric acid, adipic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid And polyglycidyl esters obtained by reaction with halogen compounds thereof).

  Among these, polyglycidyl ethers of polyhydric phenols are preferable, and glycidyl ethers of bisphenol A, bisphenol F, and 1,1-bis (4-hydroxyphenyl) ethane are more preferable. Moreover, the thing whose viscosity in 25 degreeC is 15000 mPa * s or less and whose epoxy equivalent is 180-200 is preferable.

Examples of the epoxy resin curing agent (B) include polyamine curing agents and acid anhydride curing agents.
Examples of polyamine curing agents include aliphatic polyamines having 2 to 18 carbon atoms, alicyclic polyamines having 4 to 15 carbon atoms, aromatic polyamines having 6 to 20 carbon atoms, heterocyclic polyamines having 4 to 15 carbon atoms, and polyamides. Examples include amine-based curing agents.
Examples of the aliphatic polyamine include alkylene diamines having 2 to 6 carbon atoms (ethylene diamine, propylene diamine, tetramethylene diamine, etc.), polyalkylene polyamines (dialkylene triamine to hexaalkylene heptamine having 2 to 6 carbon atoms in the alkylene group). [Diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, iminobispropylamine, bis (hexamethylene) triamine, etc.], these alkyls (alkyl group having 1 to 4 carbon atoms) or hydroxyalkyl (hydroxyalkyl group) 2) Substituents [dialkyl (alkyl group having 1 to 4 carbon atoms) aminopropylamine, diethylaminopropylamine, aminoethylethanolamine, etc.], diethyleneglycol Bis propylenediamine, include aromatic ring-containing aliphatic polyamines having 8 to 15 carbon atoms (m-xylylenediamine, etc.).

Examples of the alicyclic polyamine include isophoronediamine and bis (4-amino-3-methylcyclohexyl) methane.
Examples of the aromatic polyamine include metaphenylenediamine and diaminodiphenylmethane.
Examples of the heterocyclic polyamine include N-aminoethylpiperazine.
As the polyamidoamine-based curing agent, dimer acid containing, as a main component, a polymerized fatty acid having 36 carbon atoms produced by heating and polymerizing an unsaturated fatty acid mainly containing linoleic acid or oleic acid in the presence of a catalyst, and excess Examples thereof include those obtained by reacting polyamines (2 moles or more per 1 mole of acid) (the above-mentioned alkylene diamine, polyalkylene polyamine, etc.).

  Acid anhydride curing agents include aromatic anhydrides (phthalic anhydride, trimellitic anhydride, ethylene glycol bis (anhydrotrimellitate), glycerol tris (anhydrotrimellitate), pyromellitic anhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic anhydride, etc.], aliphatic acid anhydrides (maleic anhydride, succinic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, alkenyl Alkenyl succinic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylcyclohexenetetracarboxylic anhydride, polyadipic anhydride (weight average molecular weight: 750-850), polyazeline Acid anhydride (weight average molecular weight: 1200 to 1300), Shin anhydride (weight average molecular weight: 1600 to 1700), etc.] and the like.

Of these curing agents, polyamine curing agents are preferable, and aliphatic polyamines having 2 to 18 carbon atoms and polyamide amine curing agents are more preferable. Moreover, the thing whose viscosity in 25 degreeC is 15000 mPa * s or less is preferable.
Moreover, the ratio in which these hardening | curing agents are used is preferably 0.25 to 2.0, more preferably 0.5 to 1.75 hardening agent equivalents with respect to 1 epoxy equivalent of (A).

  As an organic hollow filler (C) used by this invention, the organic hollow filler which consists of a thermoplastic resin or a thermosetting resin, and these 2 or more types combined use are mentioned, for example.

  Examples of the thermoplastic resin include resins such as polyvinylidene chloride, polymethyl methacrylate, and polyacrylonitrile. As said thermosetting resin, resin, such as a phenol resin, an epoxy resin, and a urea resin, is mentioned, for example.

  The organic hollow filler (C) used in the present invention is preferably crosslinked at the time of molding from the viewpoint of increasing the open cell ratio of the foamed epoxy resin molded product (D).

The organic hollow filler (C) is at least one organic hollow filler (C) selected from the group consisting of the following (C1), (C2) and (C3).
(C1): Organic hollow filler (C2) having a functional group (f1) -containing vinyl monomer (g1) and a cyano group-containing vinyl monomer (g3) as essential constituent units of the shell: a functional group that reacts with the functional group (f1) The vinyl monomer (g2) having (f2) and the organic hollow filler (C3) comprising the vinyl monomer (g3) as an essential constituent unit of the shell: the vinyl monomer (g1), the vinyl monomer (g2), and the vinyl monomer ( Organic hollow filler comprising g3) as an essential structural unit of the shell

The vinyl monomer (g1) having the functional group (f1) may be any monomer having at least one functional group (f1). When having two or more (f1), (f1) may be the same type or different types.
Examples of the functional group (f1) include an isocyanato group, an epoxy group, and a hydroxymethylamino group (—NHCH ₂ OH).
The vinyl monomer (g1) includes (1) an isocyanato group-containing vinyl monomer, (2) an epoxy group-containing vinyl monomer, (3) a hydroxymethylamino group (—NHCH ₂ OH) -containing vinyl monomer, and a mixture of two or more thereof. Etc. can be used.

  (1) As an isocyanate group-containing vinyl monomer, an isocyanato group-containing vinyl monomer having 4 to 20 carbon atoms is used, and isocyanatoethyl (meth) acrylate, isocyanatopropyl (meth) acrylate, isocyanatobutyl (meth) acrylate. , Isocyanatohexyl (meth) acrylate, N-isocyanatoethyl (meth) acrylamide, N-isocyanatopropyl (meth) acrylamide, N-isocyanatobutyl (meth) acrylamide, N-isocyanatohexyl (meth) acrylamide and the like Can be mentioned.

  (2) As the epoxy group-containing vinyl monomer, an epoxy group-containing vinyl monomer having 5 to 20 carbon atoms is used, and vinyl glycidyl ether, propenyl glycidyl ether, N-glycidyl (meth) acrylamide, glycidyl (meth) acrylate and the like are used. Can be mentioned.

  (3) As the hydroxymethylamino group-containing vinyl monomer, a hydroxymethylamino group-containing vinyl monomer having 4 to 20 carbon atoms is used, and N-hydroxymethylaminoethyl (meth) acrylamide, N-hydroxymethylaminopropyl (meta ) Acrylamide, N-hydroxymethylaminopropyl (meth) acrylate, N-hydroxymethylaminoethyl (meth) acrylate and the like.

The vinyl monomer (g2) having a functional group (f2) that reacts with (f1) may be any monomer having at least one functional group (f2) that reacts with the functional group (f1). When there are two or more (f2), (f2) may be the same type or different types.
Examples of the functional group (f2) include a hydroxyl group, an amino group, an epoxy group, an isocyanato group, and a hydroxymethylamino group (—NHCH ₂ OH).
When the functional group (f1) is an epoxy group or an isocyanato group, as the vinyl monomer (g2), (4) a hydroxyl group-containing vinyl monomer, (5) an amino group-containing vinyl monomer, and a mixture of two or more of these can be used. .
When the functional group (f1) is a hydroxymethylamino group, the vinyl monomer (g2) includes (4) a hydroxyl group-containing vinyl monomer, (3) a hydroxymethylamino group-containing vinyl monomer, (2) an epoxy group-containing vinyl monomer, 1) Isocyanato group-containing vinyl monomers and mixtures of two or more thereof can be used.

(4) As the hydroxyl group-containing vinyl monomer, a hydroxyl group-containing vinyl monomer having 2 to 20 carbon atoms is used, and hydroxyalkyl (meth) acrylate {alkyl 3 to 20 carbon atoms: hydroxyethyl (meth) acrylate, hydroxypropyl ( (Meth) acrylate and hydroxybutyl (meth) acrylate and the like (the same applies to alkyl)}, hydroxyalkyl (meth) acrylamide {hydroxyethyl (meth) acrylamide, hydroxypropyl (meth) acrylamide and hydroxybutyl (meth) acrylamide}, Hydroxystyrene, (meth) allyl alcohol, crotyl alcohol, isocrotyl alcohol, 1-buten-3-ol, 2-buten-1-ol, 2-butene-1,4-diol, propargyl al , 2-hydroxyethylpropenyl ether and sucrose allyl ether, polyethylene glycol (weight average molecular weight 100 to 10000) mono (meth) acrylate, polyethylene / polypropylene glycol (weight average molecular weight 200 to 10000, oxyethylene Content of 10 to 90% by weight) mono (meth) acrylate, polypropylene glycol (weight average molecular weight 100 to 10000) mono (meth) acrylate, and the like.
Of these, hydroxyalkyl (meth) acrylate and hydroxyalkyl (meth) acrylamide are preferable from the viewpoint of mechanical strength at high temperature, and the like, more preferably hydroxyalkyl (meth) acrylate, particularly preferably hydroxyethyl methacrylate ( HEMA).

(5) As the amino group-containing vinyl monomer, an amino group-containing vinyl monomer having 4 to 50 carbon atoms can be used, and aminoalkyl (meth) acrylate {aminoethyl (meth) acrylate, aminoisopropyl (meth) acrylate, aminobutyl (Meth) acrylate and aminohexyl (meth) acrylate etc.}, aminoalkyl acrylamide {aminoethyl (meth) acrylamide, aminoisopropyl (meth) acrylamide, aminobutyl (meth) acrylamide and aminohexyl (meth) acrylamide etc}}, allylamine, Examples include crotylamine, aminostyrene, N-allylphenylenediamine, and 16- (meth) acryloylhexadecylamine.
Of these, aminoalkyl (meth) acrylates and aminoalkyl (meth) acrylamides are preferred from the viewpoint of mechanical strength at high temperatures, more preferably aminoalkyl (meth) acrylates, and particularly preferably aminoethyl (meth). Acrylate, aminoisopropyl (meth) acrylate and aminobutyl (meth) acrylate.

As the cyano group-containing vinyl monomer (g3), any vinyl polymer having a cyano group can be used without any limitation. And mixtures thereof. In addition, in this specification, (meth) acryl ... means acryl ... and methacryl ... For example, hydroxyethyl (meth) acrylate means hydroxyethyl methacrylate and hydroxyethyl acrylate, and (meth) acrylonitrile means (meth) acrylonitrile and acrylonitrile.
Among these, from the viewpoint of gas barrier properties, (meth) acrylonitrile, chloro (meth) acrylonitrile and ethoxy (meth) acrylonitrile are preferable, (meth) acrylonitrile is more preferable, and acrylonitrile is particularly preferable. The gas barrier property means a property that a volatile liquid and / or a sublimable solid contained in the polymer shell described later is difficult to leak out of the polymer shell.

The volume average particle diameter of the organic hollow filler (C) is preferably 30 μm or more, more preferably 50 μm or more, preferably 150 μm or less, and more preferably 100 μm or less.
When it is 30 μm or more, handling is easy, and when it is 150 μm or less, the resulting material can be easily reduced in weight.

The true specific gravity of the organic hollow filler (C) is preferably 0.01 or more, more preferably 0.015 or more, most preferably 0.017 or more, preferably 0.3 or less, more preferably 0.15 or less. And most preferably 0.03 or less.
The true specific gravity is preferably 0.01 or more from the viewpoint of handling properties, and 0.03 or less is preferred from the viewpoint of weight reduction of the material. The method for measuring the true specific gravity is, for example, 2. of JIS Z8807-1976 “Solid Specific Gravity Measuring Method”. It can be measured according to a measuring method using a specific gravity bottle (liquid; methanol).

  The blending amount of the organic hollow filler (C) is preferably 1 to 100% by weight with respect to the total weight of the polyepoxide (A) and the epoxy resin curing agent (B) from the viewpoint of both lightness and resin hardness. More preferably, it is 2 to 30% by weight, particularly preferably 3 to 20% by weight.

  In the foamed epoxy resin composition (E) of the present invention, an auxiliary may be used as long as it does not impair the physical properties of the molded epoxy resin product of the present invention. As the auxiliary agent, catalyst (amine-based catalyst such as triethylenediamine, N-ethylmorpholine, diethylethanolamine, 1,8-diazabicyclo (5,4,0) undecene-7; stannous octylate, dibutyltin dilaurate, Metal catalysts such as lead octylate), organic lubricants (calcium stearate, ethylenediamine stearylamide, oleic acid monoethanolamide, etc.), plasticizers (dioctyl phthalate, dioctyl adipate, etc.), thixotropic agents (fine particle silica [particle size 100nm or less], hydrogenated castor oil, organic bentonite, etc.), foam stabilizer (silicone foam stabilizer), inorganic filler (calcium carbonate, talc, aluminum hydroxide, mica, milled fiber, etc.), organic filler (heat Pulverized curable resin), UV absorber, aging Stopping agents, antioxidants, colorants (dyes, pigments), flame retardants, antifungal, can be contained and antimicrobial agents.

  The preferred amounts (% by weight) of the above-mentioned auxiliary agent to the total weight of the foamed epoxy resin composition (E) of the present invention are 0.01% or less for the catalyst and 10% or less for the organic lubricant (more preferably 0.5% ~ 5%), thixotropic agent is 5% or less, more preferably 0.5 to 5%, particularly preferably 1 to 3%, plasticizer is 10% or less, inorganic filler is 10% or less, organic The filler is 10% or less, and the others are 5% or less.

  The foamed epoxy resin molded product (D) of the present invention is formed by molding the foamed epoxy resin composition (E).

  The open cell ratio of the foamed epoxy resin molding (D) is excellent in compression set, and is preferably 30% or more, more preferably 50% or more, particularly preferably 70% or more, from the viewpoint of producing a flexible molded product. It is.

The open cell ratio can be calculated from the values of the molded body density, the true specific gravity of the molded body, and the resin density using the following formula.
Open cell ratio = (true density of molded body−density of molded body) × 100 / (resin density−density of molded body)

  The compact density can be measured according to, for example, JIS K6400-1997 [Item 5].

  For measuring the true specific gravity of the molded product, for example, the obtained molded product is cut out to 5 mm × 5 mm × 5 mm, and the JIS Z8807-1976 “Solid Specific Gravity Measurement Method” is used. It can be measured according to a measurement method using a specific gravity bottle (liquid; methanol).

  The resin density is measured, for example, by cutting the obtained molded body into 5 mm × 5 mm × 5 mm, melting under pressure (1 MPa), 250 ° C. × 1 hr, degassing, and then JIS Z8807-1976 “Solid Specific Gravity Measurement Method” 2. It can be measured according to a measuring method using a specific gravity bottle (liquid; methanol).

  The compression set of the foamed epoxy resin molded product (D) is preferably 0 to 15%, more preferably 0.5 to 10%, particularly preferably 1 to 7.5% from the viewpoint of the elasticity of the molded product. It is.

  The compression set can be measured in accordance with, for example, JIS K6382-1995 [Item 5.5].

An example of a specific manufacturing procedure of the foamed epoxy resin molded product (D) is shown below.
1. The polyepoxide (A) and the epoxy resin curing agent (B), which have been liquefied or reduced in viscosity by heating in advance, are uniformly mixed (mixed). At this time, the epoxy catalyst is preferably mixed uniformly. The epoxy group / active hydrogen group (molar ratio) is preferably from 0.8 to 1.2, particularly preferably from 0.9 to 1.1.
2. During mixing, the entrained air is removed (deaeration). A depressurization pump is usually used for deaeration.
3. The liquid is poured into a preheated mold (casting). The preheating temperature of the mold is preferably about 60 to 200 ° C.
4). Heat to cause a curing reaction (curing). The curing temperature is preferably about 60 to 200 ° C., and the curing time is preferably 2 to 60 minutes.
5). It is kept heated for a while, and after the poured liquid is cured and sufficiently strong, the cured product is removed from the mold (demolding).
6). If necessary, further heating is performed to further cure the foamed epoxy resin molded product (D) (post-curing).

  The hardness (type A) of the foamed epoxy resin molded article (D) thus obtained is preferably 50 to 120, more preferably 70 to 100 from the viewpoint of achieving both mechanical strength and flexibility.

  The foamed epoxy resin molded product (D) of the present invention is excellent in compression set, so it has both flexibility and hardness, and is lightweight, so it is suitable for use in building materials such as sealing materials, caulking materials, or metal sidings. Can be used for

EXAMPLES Hereinafter, the present invention will be further described with reference to examples, but the present invention is not limited thereto. In the following, “parts” and “%” are based on weight. Moreover, a viscosity is a viscosity in 25 degreeC.

[Raw materials and materials used]
Polyepoxide (A):
(A-1): Bisphenol F type epoxy resin (“EP-807” manufactured by Japan Epoxy Resin Co., Ltd.) Viscosity: 0.64 Pa · s.
(A-2): Bisphenol A type epoxy resin (“EP-828” manufactured by Yuka Shell) viscosity: 0.64 Pa · s.
Epoxy resin curing agent (B):
(B-1): Dimer acid-modified polyamide resin (“Polymide L-2513” manufactured by Sanyo Chemical Industries) viscosity: 0.51 Pa · s.
(B-2): Dimer acid-modified polyamide resin (“Newmide 1740” manufactured by Sanyo Chemical Industries) Viscosity; 0.34 Pa · s.

Organic hollow filler (C)
(C-1): Organic hollow filler obtained by the following production method. (Volume average particle diameter: 82.2 μm, true specific gravity: 0.023)
After uniformly mixing 340 parts of deionized water, 17 parts of a 20% colloidal silica aqueous solution, 10 parts of a 10% adipic acid-diethanolamine condensate aqueous solution and 110 parts of sodium chloride, 5.0 mmol parts of glycidyl methacrylate (GMA) was added thereto. (0.7 parts), 1526 mmol parts (80.9 parts) of acrylonitrile, 5.0 mmol parts (0.7 parts) of hydroxyethyl methacrylate, 2.0 mmol parts (0.4 parts) of ethylene glycol dimethacrylate, methacryl Add a solution consisting of 200 mmoles of methyl acid (20 parts), 20 parts of pentane and 0.5 parts of azobisisobutyronitrile, and stir for 1 minute using a homomixer (ROBOMICS, 4000 rpm, manufactured by Special Machinery Co., Ltd.). To obtain a suspension. This suspension was transferred to a pressure resistant reactor and polymerized at a gauge pressure of 0.3 MPa and 60 ° C. for 20 hours. Next, the polymerization solution was filtered and dried at 30 ° C. for 3 hours to obtain thermally expandable microcapsules. An organic hollow filler (C-1) was obtained by heating 1 g of this thermally expandable microcapsule at 180 ° C. for 3 minutes using a circulating air dryer.

(C-2): Organic hollow filler obtained by the following production method. (Volume average particle diameter: 86.2 μm, true specific gravity: 0.021)
After uniformly mixing 340 parts of deionized water, 17 parts of 20% colloidal silica aqueous solution, 10 parts of 10% adipic acid-diethanolamine condensate aqueous solution and 110 parts of sodium chloride, N-hydroxymethylaminoacrylamide (IHMA) 5 0.0 mmol (0.7 parts), acrylonitrile 1526 mmol (80.9 parts), hydroxyethyl methacrylate 5.0 mmol (0.7 parts), ethylene glycol dimethacrylate 2.0 mmol (0.4 Part), 200 mmol parts of methyl methacrylate (20 parts), 20 parts of pentane and 0.5 parts of azobisisobutyronitrile are added, using a homomixer (ROBOMICS, 4000 rpm, manufactured by Special Machinery Co., Ltd.). Stir for 1 minute to obtain a suspension. This suspension was transferred to a pressure resistant reactor and polymerized at a gauge pressure of 0.3 MPa and 60 ° C. for 20 hours. Next, the polymerization solution was filtered and dried at 30 ° C. for 3 hours to obtain thermally expandable microcapsules. An organic hollow filler (C-2) was obtained by heating 1 g of this thermally expandable microcapsule at 180 ° C. for 3 minutes using a forward air dryer.

(C-3): Organic hollow filler obtained by the following production method. (Volume average particle diameter: 83.5 μm, true specific gravity: 0.024)
340 parts of deionized water, 17 parts of a 20% colloidal silica aqueous solution, 10 parts of a 10% adipic acid-diethanolamine condensate aqueous solution and 110 parts of sodium chloride were uniformly mixed, and then N-hydroxymethylaminoacrylamide (IHMA) 10 0.0 mmol (1.4 parts), acrylonitrile 1526 mmol (80.9 parts), hydroxyethyl methacrylate 5.0 mmol (0.7 parts), ethylene glycol dimethacrylate 2.0 mmol (0.4 Part), 200 mmol parts of methyl methacrylate (20 parts), 20 parts of pentane and 0.5 parts of azobisisobutyronitrile are added, using a homomixer (ROBOMICS, 4000 rpm, manufactured by Special Machinery Co., Ltd.). Stir for 1 minute to obtain a suspension. This suspension was transferred to a pressure resistant reactor and polymerized at a gauge pressure of 0.3 MPa and 60 ° C. for 20 hours. Next, the polymerization solution was filtered and dried at 30 ° C. for 3 hours to obtain thermally expandable microcapsules. An organic hollow filler (C-3) was obtained by heating 1 g of this thermally expandable microcapsule at 180 ° C. for 3 minutes using a forward air dryer.

(C-4): Organic hollow filler obtained by the following production method. (Volume average particle diameter: 89.2 μm, true specific gravity: 0.021)
After uniformly mixing 340 parts of deionized water, 17 parts of 20% colloidal silica aqueous solution, 10 parts of 10% adipic acid-diethanolamine condensate aqueous solution and 110 parts of sodium chloride, this was added to isocyanatohexyl methacrylate (IHMA) 5.0. Millimoles (0.7 parts), acrylonitrile 1526 millimoles (80.9 parts), ethylene glycol dimethacrylate 2.0 millimoles (0.4 parts), methyl methacrylate 200 millimoles (20 parts), pentane 20 parts Then, a solution consisting of 0.5 parts of azobisisobutyronitrile was added, and the mixture was stirred for 1 minute using a homomixer (ROBOMICS, 4000 rpm, manufactured by Special Machinery Co., Ltd.) to obtain a suspension. This suspension was transferred to a pressure resistant reactor and polymerized at a gauge pressure of 0.3 MPa and 60 ° C. for 20 hours. Next, the polymerization solution was filtered and dried at 30 ° C. for 3 hours to obtain thermally expandable microcapsules. An organic hollow filler (C-4) was obtained by heating 1 g of this thermally expandable microcapsule at 200 ° C. for 30 minutes using a forward air dryer.

(C-5): Organic hollow filler obtained by the following production method. (Volume average particle diameter: 82.2 μm, true specific gravity: 0.023)
After uniformly mixing 340 parts of deionized water, 17 parts of 20% colloidal silica aqueous solution, 10 parts of 10% adipic acid-diethanolamine condensate aqueous solution and 110 parts of sodium chloride, 1531 mmol parts (80.9 parts) of acrylonitrile was added thereto. , Isocyanatohexyl methacrylate (IHMA) 5.0 mmol part (0.7 part), ethylene glycol dimethacrylate 2.0 mmol part (0.4 part), methyl methacrylate 200 mmol part (20 parts), pentane 20 parts Then, a solution consisting of 0.5 parts of azobisisobutyronitrile was added, and the mixture was stirred for 1 minute using a homomixer (ROBOMICS, 4000 rpm, manufactured by Special Machinery Co., Ltd.) to obtain a suspension. This suspension was transferred to a pressure resistant reactor and polymerized at a gauge pressure of 0.3 MPa and 60 ° C. for 20 hours. Next, the polymerization solution was filtered and dried at 30 ° C. for 3 hours to obtain thermally expandable microcapsules. An organic hollow filler (C-5) was obtained by heating 1 g of this thermally expandable microcapsule at 180 ° C. for 3 minutes using a forward air dryer.

<Volume average particle diameter>
In accordance with JIS Z8825-1: 2001, 0.1 g of a measurement sample is dispersed in 100 ml of methyl alcohol and measured using a laser scattering particle size distribution analyzer LA-920 (25 ° C., manufactured by Horiba, Ltd.). did.

<True specific gravity>
2. JIS Z8807-1976 “Method of measuring solid specific gravity” It measured based on the measuring method (liquid; methanol) by a specific gravity bottle.

Example 1
230 parts of polyepoxide (A-1), 90 parts of epoxy resin curing agent (B-1), 45 parts of organic hollow filler (C-1), and 1,8-diazabicyclo (5,4,0) undecene-70.5 The parts are mixed uniformly at 50 ° C. for 1 hour. The mixture is degassed using a vacuum pump while mixing. The obtained mixed liquid is poured into a mold preheated at 80 ° C. and reacted at 180 ° C. for 30 minutes. After demolding, the mixture was further cured for 2 hours in a circulating dryer at 120 ° C. to obtain a foamed epoxy resin molded product (D-1).

Example 2
A foamed epoxy resin molded product (D-2) was obtained in the same manner as in Example 1 except that (C-2) was used instead of the organic hollow filler (C-1).

Example 3
A foamed epoxy resin molded product (D-3) was obtained in the same manner as in Example 1 except that (C-3) was used instead of the organic hollow filler (C-1).

Example 4
280 parts of polyepoxide (A-2), 88 parts of epoxy resin curing agent (B-2), 50 parts of organic hollow filler (C-1) and 70.5 parts of 1,8-diazabicyclo (5,4,0) undecene Are uniformly mixed at 60 ° C. for 1 hour. The mixture is degassed using a vacuum pump while mixing. The obtained liquid mixture is poured into a mold preheated at 80 ° C. in advance and reacted at 200 ° C. for 45 minutes. A foamed polyurethane molding is obtained. After demolding, curing was further continued for 2 hours in a circulating air dryer at 120 ° C. to obtain a foamed epoxy resin molded product (D-4).

Example 5
A foamed epoxy resin molded article (D-5) was obtained in the same manner as in Example 4 except that (C-2) was used instead of the organic hollow filler (C-1).

Example 6
A foamed epoxy resin molded product (D-6) was obtained in the same manner as in Example 4 except that (C-3) was used instead of the organic hollow filler (C-1).

Comparative Example 1
240 parts of polyepoxide (A-1), 120 parts of epoxy resin curing agent (B-1), 45 parts of organic hollow filler (C-4), and 1,8-diazabicyclo (5,4,0) undecene-70.5 The parts were mixed uniformly at 50 ° C. for 1 hour. The mixture is degassed using a vacuum pump while mixing. The obtained mixed liquid is poured into a mold preheated at 80 ° C. and reacted at 180 ° C. for 30 minutes. After demolding, the mixture was further cured for 2 hours in a circulating dryer at 120 ° C. to obtain a foamed epoxy resin molded product (D-1 ′).

Comparative Example 2
A foamed epoxy resin molded product (D-2 ′) was obtained in the same manner as in Comparative Example 1 except that (C-5) was used instead of the organic hollow filler (C-4).

Comparative Example 3
280 parts of polyepoxide (A-2), 96 parts of epoxy resin curing agent (B-2), 50 parts of organic hollow filler (C-4), and 70.5 parts of 1,8-diazabicyclo (5,4,0) undecene Were uniformly mixed at 60 ° C. for 1 hour. The mixture is degassed using a vacuum pump while mixing. The obtained mixed solution was poured into a mold preheated at 80 ° C. in advance and reacted at 200 ° C. for 45 minutes to obtain a foamed epoxy resin molded product. After demolding, the mixture was further cured for 2 hours in a circulating dryer at 120 ° C. to obtain a foamed epoxy resin molded product (D-3 ′).

Comparative Example 4
A foamed epoxy resin molded product (D-4 ′) was obtained in the same manner as in Comparative Example 3 except that (C-5) was used instead of the organic hollow filler (C-4).

[Evaluation test]
About the foamed epoxy resin moldings (D-1 to 6) and (D-1 ′ to 4 ′) obtained in Examples 1 to 6 and Comparative Examples 1 to 4, the open cell ratio, Shore A hardness, compression set Was evaluated. The results are shown in Table 1 below.

<Open cell ratio>
It calculated using said formula from the value of a molded object density, a molded object true specific gravity, and a resin density.
<Molded body density>
The obtained molded body was cut out to 5 mm × 5 mm × 5 mm and measured according to JIS K6400-1997 [Item 5] (unit: g / cm ³ ).
<Truth specific gravity>
The obtained molded body was cut out into 5 mm × 5 mm × 5 mm, and JIS Z8807-1976 “Solid Specific Gravity Measurement Method” 2. The measurement was performed according to a measurement method using a specific gravity bottle (liquid; methanol) (unit: g / cm ³ ).
<Resin density>
The resin density was measured by cutting the obtained molded body into 5 mm × 5 mm × 5 mm, melting at 250 ° C. × 1 hr under pressure (1 MPa), degassing, and then following JIS Z8807-1976 “Solid Specific Gravity Measurement Method”. 2. It measured based on the measuring method (liquid; methanol) by a specific gravity bottle.

<Shore A hardness>
The Shore A hardness was measured according to JIS K6301. It measured using the A type spring type hardness tester, and the arithmetic average of three places was made into the measured value.

<Compression set test>
Measured according to JIS K6382-1995 [Item 5.5].

  The foamed epoxy resin molded product of the present invention had a remarkably high open cell ratio as compared with those of Comparative Examples 1 to 4, and was extremely excellent in compression set.

A molded article using the foamed epoxy resin composition of the present invention has characteristics of excellent permanent compression strain and extremely high durability. Therefore, the foamed epoxy resin molded article of the present invention is suitable for building material applications such as a sealing material, a caulking material, or a metal siding.

Claims (9)

The polyepoxide (A), the epoxy resin curing agent (B), and at least one organic hollow filler (C) selected from the group consisting of the following (C1), (C2) and (C3) are used as essential components. A characterized foamed epoxy resin composition (E).
(C1): Organic hollow filler (C2) having a functional group (f1) -containing vinyl monomer (g1) and a cyano group-containing vinyl monomer (g3) as essential constituent units of the shell: a functional group that reacts with the functional group (f1) The vinyl monomer (g2) having (f2) and the organic hollow filler (C3) comprising the vinyl monomer (g3) as an essential constituent unit of the shell: the vinyl monomer (g1), the vinyl monomer (g2), and the vinyl monomer ( Organic hollow filler comprising g3) as an essential structural unit of the shell The composition according to claim 1, wherein the true specific gravity of the organic hollow filler (C) is 0.01 or more and 0.3 or less. The composition according to claim 1 or 2, wherein the organic hollow filler (C) is crosslinked at the time of molding. The composition according to any one of claims 1 to 3, wherein the functional group (f1) is an epoxy group or an isocyanate group, and the functional group (f2) is a hydroxyl group and / or an amino group. The functional group (f1) is a hydroxymethylamino group (-NHCH ₂ OH), and the functional group (f2) is at least one selected from the group consisting of a hydroxyl group, a hydroxymethylamino group and an epoxy group. The composition in any one of 1-4. 6. The composition according to claim 1, wherein the organic hollow filler (C) has a volume average particle size of 30 μm or more and 150 μm or less. The amount of the organic hollow filler (C) is 1 to 100% by weight based on the total weight of the polyepoxide (A) and the epoxy resin curing agent (B). The composition as described. The foamed epoxy resin molding (D) formed by shape | molding the foamed epoxy resin composition in any one of Claims 1-7. The molded article according to claim 8, which is a building material.