JPH0412889B2 - - Google Patents

Description

[Detailed description of the invention]

(Technical Background) The present invention relates to an epoxy resin composition with excellent heat resistance. (Prior Art) Epoxy resin is a compound with a highly reactive epoxy group, and by utilizing this reactivity, it is used in many fields such as paints, adhesives, and electrical fields. Epoxy resins currently in use include so-called epibis-type epoxy resins produced by reacting bisphenol A and epichlorohydrin in the presence of an alkali, novolac epoxy resins produced from novolac phenol and epichlorohydrin, and others. The main ones are cycloaliphatic epoxy resins. These epoxy resins are used in a wide range of applications due to their various characteristics such as mechanical strength, adhesive strength, surface smoothness, water resistance, electrical properties, and hardenability. However, in order to take advantage of the characteristics of this epoxy resin, much more performance is still required. One of these is the demand for improved heat resistance. In order to improve the heat resistance of ordinary EPIS type epoxy resins, polynuclear cresol novolak epoxy resins are also added. Further, attempts have been made to add special epoxy resins such as tetraglycidyl diaminodiphenylmethane, triglycidyl P-aminophenol, tetraglycidyl benzophenone, and 1,3-diglycidyl hydantoin triglycidyl isocyanurate. However, these epoxy resins are still unsatisfactory due to poor compatibility, failure to obtain sufficient heat resistance, and coloration of the cured product. (Problems to be Solved by the Invention) Therefore, the inventors of the present invention made extensive studies and found that by using an epoxy resin having a cyclohexane skeleton proposed in Japanese Patent Application No. 59-014859, it is possible to solve the problem by using an epoxy resin having a cyclohexane skeleton as proposed in Japanese Patent Application No. 59-014859. The inventors have discovered that the heat resistance of novolak epoxy resins, cycloaliphatic epoxy resins, etc. can be improved, leading to the present invention. (Structure of the Invention) That is, the present invention provides ``(A) 95 to 5 parts by weight of an epoxy resin having one or more epoxy groups in one molecule.
(B) An epoxy resin composition characterized by being mixed with 5 to 95 parts by weight of an epoxy resin represented by the general formula () However, R ₁ is an organic compound residue having 1 active hydrogen. n1, n2... _nl is 0 or an integer from 1 to 100, and the sum thereof is from 1 to 100. l represents an integer from 1 to 100. A is an oxycyclohexane skeleton having a substituent, and is represented by the following formula. X is

【formula】

【formula】

[Formula] (R ₂ is any one of H, an alkyl group, an alkylcarbonyl group, or an arylcarbonyl group,

In the epoxy resin represented by the formula () which is one of the components of the epoxy resin composition of the present invention, R ₁ is an active Although it is an organic residue containing hydrogen,
Examples of organic substances having active hydrogen, which are precursors thereof, include alcohols, phenols, carboxylic acids, amines, and thiols. The alcohol may be a monohydric alcohol or a polyhydric alcohol. For example, methanol, ethanol, propanol, butanol, pentanol, hexanol,
Aliphatic alcohols such as octanol, aromatic alcohols such as benzyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, 1,3
Butanediol, 1,4 butanediol, pentanediol, 1,6 hexanediol, neopentyl glycol, oxypivalic acid neopentyl glycol ester, cyclohexanedimethanol, glycerin, diglycerin, polyglycerin, trimethylolpropane, trimethylolethane, Examples include polyhydric alcohols such as pentaerythritol and dipentaerythritol. Examples of phenols include phenol, cresol, catechol, pyrogallol, hydroquinone, hydroquinone monomethyl ether, bisphenol A, bisphenol F, 4,4'-dihydroxybenzophenone, bisphenol S, phenolic resin, cresol novolak resin, etc. be. Carboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, fatty acids from animal and vegetable oils, fumaric acid, maleic acid, adipic acid, dodecanoic acid, trimellitic acid, pyromellitic acid, polyacrylic acid, phthalic acid, isophthalic acid, terephthalic acid, etc. There is. Also included are compounds having both a hydroxyl group and a carboxylic acid, such as lactic acid, citric acid, and oxycaproic acid. Amines include methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, cyclohexylamine,
Examples include octylamine, dodecylamine, 4,4'-diaminodiphenylmethane, isophoronediamine, toluenediamine, hexamethylenediamine, xylenediamine, diethylenetriamine, triethylenetetramine, and ethanolamine. Examples of thiols include mercaptans such as methyl mercaptan, ethyl mercaptan, propyl mercaptan, and phenyl mercaptan, mercaptopropionic acid or polyhydric alcohol esters of mercaptopropionic acid, such as ethylene glycol dimercaptopropionic acid ester, trimethylolpropane trismercaptopropion Examples include acid esters, pentaerythritol tetrakismercaptopropionic acid esters, and the like. In addition, as compounds having active hydrogen, polyvinyl alcohol, polyvinyl acetate partial hydrolyzate, starch, cellulose, cellulose acetate, cellulose acetate butyrate, hydroxyethyl cellulose, acrylic polyol resin, styrene allyl alcohol copolymer resin, styrene-malein Examples include acid copolymer resins, alkyd resins, polyester polyol resins, polyester carboxylic acid resins, polycaprolactone polyol resins, polypropylene polyols, polytetramethylene glycols, and the like. Furthermore, the compound having active hydrogen may have an unsaturated double bond in its skeleton, and specific examples include allyl alcohol, acrylic acid, methacrylic acid, 3-cyclohexenemethanol, and tetrahydrophthalic acid. . The unsaturated double bonds of these compounds may also have an epoxidized structure. In the general formula (), n ₁ , n ₂ ...n _l are 0 or 1 to
It is an integer of 100, and its sum is between 1 and 100,
If it exceeds 100, the resin will have a high melting point and will be difficult to handle, making it practically unusable. l is an integer from 1 to 100. Among the substituents X of A in formula ()

Contains at least one [formula] is required, but

The more [expression] there is, the more Moderately preferable, on the contrary

[Formula] is preferably as small as possible. That is, in the present invention, the substituent X is

[Formula] is the main one. Ethnic acid used in the present invention On average per molecule of poxy resin

It is particularly preferable to have two or more of the following formulas, since the crosslinking density when cured is high. Specifically, the epoxy resin represented by the formula (), which is one of the components of the epoxy resin composition of the present invention, is produced by using an organic compound having active hydrogen as an initiator.
- Polyether resin obtained by ring-opening polymerization of vinylcyclohexene-1-oxide, that is, by epoxidizing a polycyclohexene oxide polymer having a vinyl group side chain with an oxidizing agent such as peracid. can be manufactured. 4-vinylcyclohexene-1-oxide can be obtained by partially epoxidizing vinylcyclohexene obtained by dimerization of butadiene with peracetic acid. It is preferable to use a catalyst when polymerizing 4-vinylcyclohexene-1-oxide in the presence of active hydrogen. Examples of catalysts include amines such as methylamine, ethylamine, propylamine, and piperazine; organic basic acids such as pyridines and imidazoles; formic acid;
Organic acids such as acetic acid and propionic acid, inorganic acids such as sulfuric acid and hydrochloric acid, alcoholates of alkali metals such as sodium methylate, alkalis such as KOH and NaOH, BF ₃ , ZnCl ₂ , AlCl ₃ , SnCl ₄ etc. Examples include Lewis acids or their complexes, and organometallic compounds such as triethylaluminum and diethylzinc. These catalysts can be used in an amount of 0.01 to 10%, preferably 0.1 to 5%, based on the reactants.
Reaction temperature is -70~200℃, preferably -30℃~100℃
It is. The reaction can also be carried out using a solvent. A solvent containing active hydrogen cannot be used. That is, ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, aromatic solvents such as benzene, toluene, and xylene, as well as ethers, aliphatic hydrocarbons, esters, and the like can be used. Now, in order to produce the epoxy resin (), which is one of the components of the epoxy resin composition of the present invention, by epoxidizing the polycyclohexene oxide polymer having vinyl group side chains synthesized in this way, peracids, hydrocarbons, etc. Peroxides can be used. As peracids, performic acid, peracetic acid, perbenzoic acid, trifluoroperacetic acid, etc. can be used. Among these, peracetic acid is a particularly preferred epoxidizing agent because it is industrially available at low cost and has high stability. As the hydroperoxides, hydrogen peroxide, tertiary butyl, hydroperoxide, cumene oxide, etc. can be used. A catalyst can be used during epoxidation if necessary. For example, in the case of a peracid, an alkali such as soda carbonate or an acid such as sulfuric acid may be used as a catalyst. In the case of hydroperoxide, a mixture of tungstic acid and caustic soda is mixed with hydrogen peroxide,
Alternatively, the catalytic effect can be obtained using organic acids with hydrogen peroxide or molybdenum hexacarbonyl with tertiary butyl hydroperoxide. The epoxidation reaction is carried out by adjusting the presence or absence of a solvent and the reaction temperature depending on the equipment and physical properties of the raw materials. Depending on the conditions of the epoxidation reaction, olefin bonds can be epoxidized and substituents in the raw materials can be and the substituents that are generated. As a result of a side reaction with an epoxidizing agent etc., modified substituents are generated and included in the target compound. Substituent in target compound

[Formula] Substituent The ratio of the three modified substituents is determined by the type of epoxidizing agent, the molar ratio of the epoxidizing agent to the olefin bond, and the reaction conditions. For example, when the epoxidizing agent is peracetic acid, the modified substituent mainly has the structure shown below, and is generated from the generated epoxy group and by-produced acetic acid. The target compound can be taken out from the reaction crude solution by ordinary chemical industrial means such as concentration. The epoxy resin having one or more epoxy groups in one molecule used in the present invention is a commonly known epoxy resin, and is not particularly limited. Examples include bisphenol A type epoxy resin, bisphenol F type epoxy resin, cresol novolak type epoxy resin, alicyclic epoxy resin, heterocyclic type epoxy resin, cresol novolak type epoxy resin, and phenol novolak type epoxy resin. However, particularly preferred are products such as Epicote 827, Epicote 828, Epicote 1001, Epicote 1004, and Epicote 1009 manufactured by Ciel Co., Ltd., or equivalent products from many companies, such as Epiclon 830 or Epiclon 3,4 manufactured by Dainippon Ink Co., Ltd. Epoxy resins such as -epoxycyclohexylmethyl-3,4 epoxycyclohexane carboxylate (trade name: Celoxide 2021, manufactured by Daicel Chemical Industries, Ltd.) can be used, and they may be used alone or in a mixture of two or more types. The epoxy resin composition of the present invention has (A) 1 in 1 molecule.
Epoxy resin 95-5 with more than 3 epoxy groups
It is obtained by mixing parts by weight of the epoxy resin (B) with 5 to 95 parts by weight of the epoxy resin represented by the general formula (). Preferably (A) 80-20 parts by weight and (B) 20-80 parts by weight. If (A) is less than 5 parts by weight, the characteristics of (A) cannot be maintained,
If (B) is less than 5 parts by weight, sufficient heat resistance cannot be obtained. (A) and (B) can be mixed in a molten state. Further, it can be dissolved and mixed in a suitable solvent such as acetone, methyl ethyl ketone, butyl acetate, toluene, benzene, etc. Alternatively, so-called dry blending may be performed in a powdered state. (Effects of the Invention) The epoxy resin composition obtained in the present invention can be cured with commonly used epoxy curing agents such as acid anhydrides, aliphatic amines, aromatic amines, novolac phenols, and dicyandiamide, and is heat resistant. A cured product with excellent properties can be obtained. Therefore, it can be widely used in various applications such as paints, adhesives, and electrical fields. The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples. Synthesis example 1 Allyl alcohol 58g (1 mol), 4-vinylcyclohexene-1-oxide 868g (7 mol)
and 4.7 g of BF ₃ etherate were mixed at 60°C,
The reaction was continued until the conversion of 4-vinylcyclohexene-1-oxide reached 98% or more as determined by gas chromatography analysis. Ethyl acetate was added to the obtained reaction crude liquid and washed with water, and then the ethyl acetate layer was concentrated to obtain a viscous liquid. In the infrared absorption spectrum of the product, the absorption due to epoxy groups at 810 and 850 cm ^-1 observed in the raw material has disappeared, and absorption due to ether bonds exists at 1080 and 1150 cm ^-1 , and gas chromatography analysis shows that , the amount of allyl alcohol in the product is only trace, but it is 3450 in the infrared absorption spectrum.
It was confirmed that this compound has the structure shown by the following formula from the absorption of OH group at cm ^-1 . 40.2 g of this compound was dissolved in ethyl acetate and charged into a reactor, to which 39.5 g of peracetic acid was added dropwise as an ethyl acetate solution over 2 hours. During this time, the reaction temperature was maintained at 40°C. After the completion of peracetic acid preparation, 40
It was aged for an additional 6 hours at °C. Ethyl acetate was added to the reaction crude solution, and the mixture was washed with alkaline water containing sodium carbonate, and then thoroughly washed with distilled water. The ethyl acetate layer was concentrated to obtain a viscous clear liquid. This compound has an oxirane oxygen content of 9.27%
In the infrared absorption spectrum, characteristic absorption due to epoxy groups was observed at 1260 cm ^-1 . Furthermore, 1640cm ^-1
Absorption due to residual vinyl groups is observed in 3450
OH group at cm ^-1 , 1730 cm ^-1

[Formula] This compound has a structure of the general formula () (R ₁ : glycidyl group or allyl group, n=
7 on average, including some groups in which acetic acid was added to epoxy groups). Synthesis Example 2 In the same manner as in Example-1, 134 g of trimethylolpropane, 4-vinylcyclohexene-1-
186.3 g of oxide was reacted to obtain a viscous liquid product. In the infrared absorption spectrum of the product, the absorption due to epoxy groups at 810 and 850 cm ^-1 observed in the raw material has disappeared, and the absorption due to ether bonds exists at 1080 and 1150 cm ^-1 , and the NMR
Analysis confirmed that this compound has the structure shown by the following formula. Furthermore, 573 g of this compound was reacted with 387 g of peracetic acid in the same manner as in Synthesis Example 1 to obtain a viscous transparent liquid. This compound has an oxirane oxygen content of 9.03%
In the infrared absorption spectrum, characteristic absorption due to epoxy groups was observed at 1260 cm ^-1 . Furthermore, 1640cm ^-1
Absorption due to residual vinyl groups is observed in 3450
OH group at cm ^-1 , 1730 cm ^-1

[Formula] This compound has a structure of the general formula () (R ₁ : trimethylolpropane residue l=
3, n ₁ , n ₂ , n ₃ = 5 on average, including one portion of a group obtained by adding acetic acid to an epoxy group). Examples 1 to 4, Comparative Examples 1 to 2 Epoxy resins obtained in Synthesis Examples 1 and 2 and 3,4-epoxycyclohexylmethyl-3',
4′ epoxycyclohexane carboxylate (Celoxide 2021 manufactured by Daicel Chemical Industries, Ltd.) Epicote 828 (bisphenol A type epoxy resin manufactured by Yuka Sil Epoxy Co., Ltd.), methylhexahydrophthalic anhydride as a curing agent, and benzyl dimethyl as a catalyst. Amine 0.5%, curing agent/epoxy resin = 0.8 (equivalent ratio)
The samples were cured at the blending (parts by weight) ratio shown in Table 1, and the heat distortion temperatures were compared. Curing conditions Pre-curing: 130℃ x 3 hours Post-curing: 180℃ x 2 hours

【table】

Claims (1)

[Scope of Claims] 1 (A) 95 to 5 parts by weight of an epoxy resin having one or more epoxy groups in one molecule; and (B) 5 to 95 parts by weight of an epoxy resin represented by the general formula ().
An epoxy resin composition characterized by being formed by mixing parts by weight with However, R ₁ is an organic compound residue having 1 active hydrogen. n1, n2... _nl is 0 or an integer from 1 to 100, and the sum thereof is from 1 to 100. l represents an integer from 1 to 100. A is an oxycyclohexane skeleton having a substituent, and is represented by the following formula. X is [Formula] [Formula] [Formula] (R ₂ is any one of H, an alkyl group, an alkylcarbonyl group, or an arylcarbonyl group, and [Formula] is at least a resin represented by the formula () (contains one or more)