JPS6243413A - Thermosetting resin composition - Google Patents

Abstract

PURPOSE:The titled composition having improved impact resistance, crack resistance and high heat distortion temperature, obtained by blending an epoxy resin with a curing agent, a polymerizable monomer and a radical polymerizable initiator in such a way that the density of the cured blend of these components satisfies a specific condition. CONSTITUTION:(A) An epoxy resin is blended with (B) a curing agent (e.g. phthalic anhydride, etc.,) for the component A, (C) a radically polymerizable double bond-containing monomer (preferably glycidyl acrylate, etc.,) and (D) a radical polymerization initiator (e.g., benzoyl peroxide, etc.,), respectively, under a condition where the density deltamix of the cured blend of the components A-D satisfies the formula (DELTAA+B is density of cured blend of the components A and B; deltaC+D is density of cured blend of the components C and D; deltaA+B is weight fraction of blend of the components A and B, deltaC+D is weight fraction is blend of the components C and D), to give the aimed composition.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a thermosetting resin composition, and more particularly to a thermosetting resin composition that has excellent impact resistance and crack resistance, and has a high heat distortion temperature. relating to things.

(Prior art) Epoxy resins can be provided in various grades from liquid to solid at room temperature, can be cured at room temperature or under heating depending on the curing agent selected, and do not produce by-products during curing. In addition, the cured product has excellent adhesive strength, mechanical strength, and electrical properties, and has good chemical properties such as chemical resistance and moisture resistance. It is widely used in the fields of paint, electrical insulation materials, civil engineering, building materials, adhesives, etc.

However, depending on the conditions of use, epoxy resins may produce cranks in their cured products, and the following methods have been proposed for the purpose of improving crank resistance.

(1) Lower the concentration of epoxy groups contained in the epoxy resin and reduce the degree of stiffness.

(2) Long-chain aliphatic substituents and the like are introduced to impart aliability to the resin.

(3) Aliphatic polyamide, polyacid anhydride, long chain po”!
Use long-chain curing agents such as mercaptans.

(4) Monofunctional Epokin is used in combination to achieve so-called intramolecular plasticization.

(5) Mixing non-reactive plasticizing components such as polyoquinoalkylene ether, phthalate ester, and polycaprolactone.

However, all of these methods have the drawback that the heat distortion temperature, which is one of the measures of heat resistance 11, is significantly lowered.

In addition, by incorporating a large amount of inorganic filler whose coefficient of thermal expansion is smaller than that of the resin component, the coefficient of thermal expansion of the system is reduced.
Methods of improving crack resistance are also widely used.

However, although this method does not lower the heat distortion temperature of the 4!1 fat component, it does not improve the cracking resistance of the 4!1 fat component itself, so it has its limitations, and the viscosity of the system increases. He had the disadvantage of being inferior to himself.

In addition, in recent years, with the aim of improving the properties of tetrad materials, studies have been conducted on so-called polymer alloy technology, which aims to add new functions and improve performance by combining different materials or different crosslinked structures. It is being done,
For example, the Journal of Polymer Science (Jo
urnaf ofPoI2ymer 5cienc
e, PoJymer Symposium), Vol. 46 (1974), p. 175, describes that mechanical properties can be improved by combining an epoxy resin and a non-functional acrylic monomer to form an interpenetrating polymer network. It is shown.

However, this method also has the disadvantage that in the case of the above combination, improvement in mechanical properties can only be observed within a limited range, and the reality is that it has not been used industrially. be. That is, in this case, since only physical interaction exists between the epoxy resin component and the mono-7-component, the effect of improving mechanical properties is only expressed under the cumulative composition ratio and curing conditions. It is estimated that

(Problems to be Solved by the Invention) It is an object of the present invention to eliminate the drawbacks of the prior art, to have excellent impact resistance and crack resistance, high sudden deformation temperature, and to be able to withstand a wide range of working conditions. The object of the present invention is to provide a thermosetting resin composition that exhibits stable performance.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present inventors have made a thorough investigation and found that a composition containing four components: an epoxy resin, a curing agent, a polymerizable monomer, and a radical polymerization initiator. The inventors have discovered that the above object can be achieved when the density of the cured mixture satisfies a specific relationship, and the present invention has been achieved.

The present invention provides epoxy resins having more than one epoxy group in the molecule (component A), curing agents for epoxy resins (component B),
), a polymerizable monomer having a radically polymerizable double bond in the molecule (component C) and a radical polymerization initiator for polymerizing the polymerizable monomer (component D), and the component A The present invention relates to a thermosetting resin composition in which a partially cured product obtained by partially curing ~D has a density that satisfies formula (1).

(In the formula, δmix is the density of the mixed cured product, δA+B is the density of the mixed cured product of component A and component B, δC+D is the density of the mixed polymer of component C and component R, and ωA+8 is the density of the mixed cured product of component A and component B. The weight fraction of the mixture with component B and ωC+D mean the weight fraction of the mixture of component C and component C).

Examples of the epoxy resin (component A) having more than one epoxy group in the molecule used in the present invention include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol A to D epoxy resin, and polyhydric alcohol. polyglycidyl esters of polybasic acids, 3,4-epoxycyclohexylmethyl (3゜4-epoxycyclohexane) carboxylates, alicyclic epoxy resins such as vinylcyclohexene diepoxide, phenol novolak type epoxy resins, cresols Examples include novolank type resins and epoxy resins having a hydantoin ring.

Examples of the curing agent for epoxy resins (component B) used in the present invention include phthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, maleic anhydride, dodecenylsuccinic anhydride, etc. acid anhydride, diethylenetriamine, diethylaminopropylamine, metaxylylenediamine, 3.
9-bis(3-aminopropyl)-2,4,8,10-
Aliphatic polyamines such as tetraoxaspiro(5,5)undecane, aromatic polyamines such as metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, and modified polyamines obtained by adding these polyamines and epoxy compounds. , piperidine,
Examples include secondary or tertiary amines such as tris(dimethylaminemethyl)phenol and hensyl dimethylamine, polysulfides, imidazoles such as 2-ethyl-4-methylimidazole, and dicyandiamide.

The polymerizable monomer (component C) having a radically polymerizable double bond in the molecule used in the present invention includes, in addition to the radically polymerizable double bond in the molecule, an epoxy group, a hydroxyl group, a carboxyl group, etc. It is preferable to use a polymerizable monomer having a functional group of Examples of this include glycidyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxylpropyl (meth)acrylate, 2-hydroxy-3-(2'-ethylhexoxy)
Propyl acrylate, ethylene glycol-bis(2
-hydroxy-3-methacryloyloxypropyl) ether, propylene glycol-bis(2-hydroxy-3-methacryloyloxypropyl) ether, 2-
hydroxy-3-phenoxypropyl methacrylate,
2-hydroxy-3-butoxypropyl acrylate,
(meth)acrylic acid, 2-(meth)acryloyloxyethyl phthalic acid, 2-(meth)acryloyl oxyneethyltetrahydrophthalic acid, 2-(meth)acryloyloxyethyl hexahydrophthalic acid, 2-(meth)acryloyl Oxyethylmethyl hexahydrophthalic acid, 2
-(meth)acryloyloxyethylsuccinic acid, 2-(
Examples include meth)acryloyloxyethylmaleic acid, 2-(meth)acryloyloxypropylphthalic acid, 2-(meth)acryloyloxypropylmaleic acid, monobutyl fumarate, 2-hydroxy-3-phenoxypropylmaleate, etc. .

In addition, polymerizable monomers that do not have functional groups other than radically polymerizable double bonds, such as diethylene glycol di(meth)
Poly(meth)acrylates of polyols such as acrylates, alkyl(meth)acrylates such as methyl(meth)acrylate, aromatic vinyl monomers such as styrene and divinylbenzene, etc. are also used, but these are radically polymerizable as described above. It is preferable to use it in combination with a polymerizable monomer having a functional group in addition to a double bond.

In the present invention, examples of the radical polymerization initiator (component D) used to polymerize the polymerizable monomer (component C) include t-butyl perhenzoate, t-butyl peroctoate, cumene hydroper Examples include organic peroxides such as oxide and hensyl peroxide, abbisisobutyronitrile, and the like.

The resin composition of the present invention comprises the epoxy resin (component A).
), a thermosetting resin composition containing a curing agent for epoxy resin (component B), a polymerizable monomer having a radically polymerizable double bond in the molecule (component C), and a radical polymerization initiator (component D) It is obtained by blending so that the mixed cured product has a density that satisfies the above formula (1).

At this time, the curing agent for epoxy resin (component B) is used in an amount sufficient to cure the epoxy resin (component A).

The blending amount (metal ratio) of component B to component A varies depending on the curing agent used, but in the case of an acid anhydride curing agent, it is 0.
3 to 1.4 equivalents are preferred. This is mainly to prevent a decrease in heat distortion temperature. Again-? In the case of min-based hardeners, the blending amount is the epoxy equivalent! Taking an epoxy equivalent of 90 as an example, it is preferably 2 to 60 parts by weight based on 100 parts by weight of the resin.

The amount of the polymerizable monomer (component C) used is preferably 5 to 50 parts by weight based on 100 parts by weight of the Evokin resin (component A) from the viewpoint of crack resistance, heat distortion temperature, and shrinkage during curing.

The amount of the random polymerization initiator (component D) used is the amount necessary to polymerize the polymerizable monomer (component C), and is based on the polymerization rate of the polymerizable monomer and the required molecular weight of the polymer. 0 for 100 parts by weight of polymerizable monomer (component C)
．． 2 to 5 parts by weight is preferred.

The resin composition of the present invention further includes a reaction catalyst such as butyl glycidyl ether, a phenyl glycidyl ether compound, and tertiary amines, a filler such as silica, aluminum hydroxide, and calcium carbonate, etc. Flame retardants such as gen compounds, antimony trioxide, and red phosphorus, coupling agents, coloring agents, and the like can be blended.

The curing temperature of the thermosetting resin composition of the present invention is preferably in the range of 80 to 180°C when using an acid anhydride curing agent, and from 0 to 180°C when using an amine curing agent.
The temperature is preferably in the range of 150°C.

The thermosetting (8-fat composition) of the present invention is limited to one in which the mixed cured product obtained by mixing and curing the components A to D has a density that satisfies the above formula (1).

If the density of the resulting cured mixture does not satisfy the formula (1), the iL impact resistance and crack resistance will be poor, and the heat distortion temperature will also significantly decrease.

(Effects of the Invention) The thermosetting resin composition of the present invention has excellent impact resistance and crack resistance, and also has a high heat distortion temperature. The thermosetting resin composition of the present invention has a cracking temperature of about 2% compared to resin compositions obtained by conventional methods.
It is excellent and low by 0 to 50°C.

The resin composition of the present invention can be used in a wide range of fields such as paints, electrical insulation materials, civil engineering and construction materials, and adhesives.

(Example) "Part" in the following examples means the part where M is placed.

Examples 1 and 2 and Comparative Examples 1 to 3 Each resin composition was prepared by blending the compounds shown in Table 1 in the proportions (parts) shown in the table. This composition was cast into a mold of a predetermined shape and cured at 80° C. for 5 hours and then at 120° C. for 5 hours to obtain a cured product.

Using these cured products, thermal deformation temperature, bending strength, eye impact strength, crack initiation temperature, and density difference of the cured products were measured. The results are shown in Table 1.

The evaluation method for each characteristic is as follows.

(1) Heat distortion temperature: 1 2 0 x 1 2. 5 x 5 test specimens were prepared and measured according to ASTM D648.

(2) Bending strength: Using a 120x5x12.5tm test piece, JIS
Measured according to K6911.

(3) Izot impact strength: 4 5 X 1 2. It was measured using a 5 x 5 mm test piece without a notch, and the obtained value was divided by the cross-sectional area of the test piece.

(4) Crack generation temperature: A 2-inch stainless steel spring washer was set in a metal Petri dish with a diameter of 60 nm, and 30 g of the composition was injected and cured to obtain a test piece. After curing, remove the petri dish and heat at 23℃.
After being left for 72 hours, a 100-b cycle test was conducted to observe the occurrence of cracks. For samples where cranking did not occur, the low temperature side was 10℃.
Similar tests were conducted with the temperature lowered, and the temperature at which cracks occurred was determined by successively lowering the temperature. Note that two test pieces were used for each test piece, and the average value was expressed.

The symbols in the table have the following meanings.

*: Cracks occur during cooling after hardening of the sample **: Cracks occur during storage at 23°C after hardening of the sample (5) Difference in density of cured product: Density δmi × of mixed cured product by underwater displacement method, epoxy Resin (component A) and curing agent (including curing catalyst) (component B
) and the density δ of the mixed polymer with the polymerizable monomer component C) 1 initiator (component D).
C+D was measured, and the difference between the value on the left side and the value on the right side of the equation (1) was determined from these values. In addition, the mixed polymer of the polymerizable monomer (component C) and the polymerization initiator (component D) is heated at 80°C.
The reactant was reacted at 110° C. for 24 hours and then at 110° C. for 5 hours.

Qt'! 2. Below margin (ai) 1>Bisphenol A type Evokin resin, Epokin group equivalent +90, manufactured by Yuka Noel Epokin Co., Ltd.? ) Menaltetrahydrophthalic anhydride, Hitachi Chemical V (
Co., Ltd. 3) 2-Hydroxoethyl methacrylate 4) 2-methacryloyl oxyneethyl phthalic acid 5) 2-ethylhexyl methacrylate Examples 3 to 5
and Comparative Example 4 Each resin composition was prepared by blending the compounds shown in Table 2 at the proportions (parts) shown in the table, and each property was measured using this composition in the same manner as in Example 1. The results are shown in Table 2.

Table 2 below (li↑) l) 2-Hydroxy-3-phenoxypropyl methacrylate 2) 2-methacryloyloxyethylmaleic acid 3) Diethylene glycol dimethacrylate Based on the results of Tables 1 and 2, It is shown that the thermosetting resin composition of the invention has excellent impact resistance and crack resistance, and has a high heat distortion temperature (without impairing heat resistance).

Agent Patent Attorney Kunihiko Wakabayashi Procedural Amendment (Voluntary) VI III QQ ll! Q lj 171+l・Table of outsourcing・'I: 1985 Patent Application No. 182814 2 Name of invention Thermosetting resin composition 3 Correct relationship with M↑ Patent applicant R, Ne 4
45th day! 1 Kasei Ohsai Co., Ltd. 714 Representative
Hitachi Chemical Li Co., Ltd. 4 in 1! Story East jλ3 envy-3111i Jindai k) Name
(71551 Patent Attorney Wakabayashi
Luhiko.

~20°(/1hJ means r100'c/1hr-
Corrected to 20°C/1hrj (21st.

that's all

Claims (1)

[Claims] 1. An epoxy resin having more than one epoxy group in the molecule (component A), a curing agent for epoxy resin (component B), and a polymerizable monomer having a radically polymerizable double bond in the molecule. Quantity (
Contains component C) and a radical polymerization initiator (component D) for polymerizing the polymerizable monomer, and the components A to
A thermosetting resin composition in which a cured mixture obtained by mixing and curing D has a density that satisfies formula (1). (1/δmix)<{[(ωA+B)/(δA+B)]
+[(ωC+D)/(δC+D)]}(1) (where δm
ix is the density of the cured mixture, δA+B is the density of the cured mixture of components A and B, δC+D is the density of the mixture of components C and D, and ωA+B is the weight of the mixture of components A and B. fraction and ωC+D mean the weight fraction of the mixture of components C and D).