JPH034564B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermosetting resin composition having excellent mechanical strength. [Conventional technology and problems] Epoxy resin has been widely used as a matrix resin for various electrical parts and reinforced plastics because of its excellent mechanical strength, heat resistance, and electrical properties. The point is that the strength is low. Adding rubber components has been used as a method to improve impact strength, but
Addition of a rubber component often results in a decrease in elastic modulus and electrical properties, so a resin with high impact strength without the addition of a rubber component is desired. [Means and effects for solving the problems] The present inventors have conducted extensive research on thermosetting resin compositions that provide cured products with high elastic modulus and impact strength without the addition of rubber components. , arrived at the present invention. That is, the present invention provides general formula () (In the formula, Ar represents a C ₆ to _{C 20} aromatic hydrocarbon having at least one glycidyloxy group, R is a hydrogen atom or a methyl group, and n is 1 to 4
The gist of the invention is a thermosetting resin composition comprising a glycidyl compound and a polyamine represented by the following integer. The glycidyl compound () of the present invention is produced by a method for which the present inventors have already applied for a patent (Japanese Patent Laid-Open No. 130580/1986).
It can be manufactured by Glycidyl compounds () that can be used in the present invention are not particularly limited, but examples include glycidyl compounds represented by the following structural formulas (), (), (), and (). (In the formula, R is a hydrogen atom or a methyl group) (In the formula, R is a hydrogen atom or a methyl group, n is 1
or 2) (In the formula, R is a hydrogen atom or a methyl group, n is 1 or 2, and R' is a monovalent C ₆ to C ₁₀ aromatic hydrocarbon group, which has an alkyl or halogen substituent on the aromatic nucleus. ) (In the formula, R is a hydrogen atom or a methyl group, n,
(n' represents 0 or an integer of 1 to 2, and at least one of n and n' is 1 or more). A cured product with excellent mechanical strength can be obtained (JP-A-60-130580, JP-A-60-252624). These perform both the radical polymerization of the acrylamide group and the reaction of the glycidyloxy group and the curing agent at the same time, and the amount of curing agent used in the epoxy resin is as follows:
In the reaction with the glycidyloxy group, it is usually used in a stoichiometric amount, for example, in the case of using a polyamine, it is used in an amount of about 1 equivalent based on the number of moles of the glycidyloxy group. (Here, 1 equivalent of polyamine refers to the value obtained by dividing the molecular weight of polyamine by the total number of N--H bonds of amine groups contained therein. The same applies hereinafter). In this case, unless a radical initiator is used, a cured product cannot be obtained, or even if a cured product is obtained, it is extremely poor in mechanical strength and heat resistance. Surprisingly, the amount of polyamine used is about 1 equivalent based on the sum of the number of moles of acrylamide groups and glycidyl groups of the glycidyl compound (),
It has been found that when thermal curing is carried out without a radical initiator, a cured product with very good mechanical strength can be obtained. Furthermore, this cured product has a higher flexural modulus than ordinary epoxy resins, and also has extremely high impact strength. In the present invention, the amount of polyamine used is around 1 equivalent, more specifically 0.75 to 1.5 equivalent, based on the sum of the moles of acrylamide group and glycidyl group.
It is possible to obtain an extremely tough cured product that exceeds expectations. In fact, if the polyamine is used in an amount of about 1 equivalent to the number of moles of glycidyl groups without a radical initiator, a cured product with sufficient strength cannot be obtained as described above. These facts show that when a radical initiator is not used, a cured product with sufficient strength can only be obtained by reacting the polyamine with the glycidyl group and the polyamine with the acrylamide group. This cured product can be said to be a new type of cured product that has not been previously known. The reaction between a polyamine and an acrylamide group is considered to be an addition reaction of an amino group to an acrylamide group as shown in the following formula. The polyamine used in the present invention is not particularly limited as long as it is a bifunctional to trifunctional or more functional aliphatic and aromatic polyamine, but examples include ethylenediamine, triethylenetetramine, decamethylene diamine, hexamethylene diamine, m- and p-
xylylene diamine, isophorone diamine, 1,
4-cyclohexanediamine, 1,3-cyclohexanediamine, N-aminoethylpiperazine,
Aliphatic polyamines such as menthanediamine and
- and p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, 2,6-diaminopyridine, 2,4-toluene Examples include aromatic polyamines such as diamines. The composition of the present invention cures without a curing accelerator, but may optionally contain phenols, alcohols, organic acids, inorganic acids, tertiary amines, polymerkabutane,
Curing accelerators such as imidazoles and boron fluoride-amine complexes may be used in combination. The curing reaction of the composition of the present invention can be carried out at temperatures around room temperature to above room temperature. More preferably, the curing reaction can be carried out at a temperature of 70 to 200°C. In order to obtain sufficient strength, it is preferable to perform post-curing at a temperature of 100°C or higher. In addition to being used as is, the composition of the present invention may be used in combination with other fibrous reinforcing materials, such as glass fibers or carbon fibers, or inorganic fillers, such as calcium carbonate, clay, aluminum oxide, etc. It is possible. It is also possible to add commercially available epoxy resins to the compositions of the invention. In this case, it is preferable from the viewpoint of mechanical strength to increase the amount of amine used in accordance with the amount of epoxy resin added. [Examples] Next, the present invention will be explained using Examples, but the present invention is not limited to these Examples. Note that all numbers of parts used represent parts by weight. Example 1 N-(4-glycidyloxy-3,5-dimethylphenylmethyl)acrylamide (corresponds to the structural formula () in which R is a hydrogen atom and has an epoxy equivalent of 261. The same applies hereinafter) 100 32.8 parts of isophorone diamine was added to each part, and a curing reaction was carried out at 100°C for 2 hours and at 150°C for 10 hours. The mechanical strength of the obtained cured product was as follows. Heating deformation strain temperature 122℃ (Load 18.5Kg.f/cm ² ) Tensile strength 776Kg/cm ² Bending strength 1296Kg/cm ² Bending modulus 45200Kg/cm ² Izot impact strength 4.8Kg・cm/cm (With V-notch) Comparison Example 1 100 parts of diglycidyl ether of bisphenol-A (Epicote 828 from Yuka Ciel Epoxy Co., Ltd.),
The mechanical strength of the cured product obtained by mixing 22 parts of isophoronediamine and curing in the same manner as in Example 1 was as follows. Heating deformation strain temperature 125℃ (Load 18.5Kg.f/cm ² ) Tensile strength 556Kg/cm ² Bending strength 1270Kg/cm ² Bending modulus 31500Kg/cm ² Izot impact strength 3.0Kg・cm/cm (With V-notch) Comparison Example 2 16.4 parts of isophorone diamine was added to 100 parts of N-(4-glycidyloxy-3,5-dimethylphenylmethyl)acrylamide and a curing reaction was carried out in the same manner as in Example 1, but no curing occurred. . Example 2 Various compounds shown in Table 1 were used as polyamine components in the amounts shown in Table 1, based on 100 parts of N-(4-glycidyloxy-3,5-dimethylphenylmethyl)acrylamide. The curing reaction was carried out in the same manner. Table 1 shows the heating deformation strain temperature and Izod impact strength of the obtained cured product. 【table】

Claims (1)

[Claims] 1 (a) General formula () (In the formula, Ar represents a C ₆ to C ₂₀ aromatic hydrocarbon having at least one glycidyloxy group, R is a hydrogen atom or a methyl group, and n is 1
A thermosetting resin composition comprising a glycidyl compound represented by (an integer of ~4) and (b) a polyamine. 2. The composition according to item 1, wherein the amount of polyamine b is 0.7 to 1.5 equivalents based on the sum of the moles of acrylamide groups and glycidyloxy groups of glycidyl compound a. 3 Glycidyl compound a has the structural formula () (wherein R is a hydrogen atom or a methyl group) The composition according to claim 1 or 2, which is a compound represented by the following formula. 4 Glycidyl compound a has the structural formula () (In the formula, R is a hydrogen atom or a methyl group, n is 1
or 2) The composition according to claim 1 or 2, which is a compound represented by: 5 Glycidyl compound a has the structural formula () (In the formula, R is a hydrogen atom or a methyl group, and R' is a monovalent C ₆ to C ₁₀ aromatic hydrocarbon group, which may have an alkyl or halogen substituent on the aromatic nucleus. n represents an integer of 1 or 2) The composition according to claim 1 or 2, which is a compound represented by the following. 6 Glycidyl compound a has the structural formula () (In the formula, R is a hydrogen atom or a methyl group, n,
The composition according to claim 1 or 2, wherein n' represents 0 or an integer of 1 to 2, and at least one of n and n' is 1 or more. 7. The composition according to claim 1 or 2, wherein polyamine b is an aliphatic diamine. 8. The composition according to claim 1 or 2, wherein polyamine b is an aromatic diamine.