JPH0431410A - Curable resin composition - Google Patents

Abstract

PURPOSE:To obtain the title compsn. excellent in low-temp. curing properties, heat resistance, and mechanical strengths by compounding a maleimide compd. with an N-substd. cycloaliph. amine having at least two N-vinylbenzyl groups. CONSTITUTION:A maleimide compd. (e.g. N,N'-diphenylmethanebismaleimide) is compounded with an N-substd. cycloaliph. amine having at least two N- vinylbenzyl groups in the molecule [e.g. a compd. of the formula (wherein X is a residue of a cycloaliph. amine from which y H atoms of amino groups are removed; and y is 2-6) obtd. from a cycloaliph. amine, e.g. piperazine] to give the title compsn., which is amorphous, lowly viscous, excellent in workability, low-temp. curing properties, heat resistance, and mechanical strengths, and hence widely used for an adhesive, for a casting, impregnating, or laminating material, and for a coating, insulating, or composite material.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a curable polymaleimide resin composition. In particular, the present invention relates to a curable resin composition that is excellent in low-temperature curing, heat resistance, and mechanical properties.

[Conventional technology]

Curable compositions are widely used as adhesives, castings, coatings, impregnations, laminations, molding compounds, etc. in paints, insulating materials, composite structural materials, and the like.

Among them, polyimide resin is one of the most excellent materials, and various developments are being promoted. For example, a composition of a polymaleimide compound and a reactive oligomer having an alkenyl ether at the end of the molecule is disclosed in JP-A-62-53319.
Known by the number.

[Problem to be solved by the invention]

However, the above-mentioned resin composition has a high curing temperature,
The curing time is long, and in terms of workability including this,
It still cannot be said to be advantageous compared to existing general-purpose curable resins.

In addition, in recent years, curable resins have been used for a wide variety of purposes, so the curable resin compositions that have been used traditionally are
It is not possible to be completely satisfied under various usage environments or usage conditions. In particular, the heat resistance and hot strength when used at high temperatures are insufficient, and even the most typical compositions, such as the combination of bismaleimide, aromatic amine, and epoxy resin, are
Sufficient materials were not yet available.

Therefore, the present invention solves the above-mentioned problems of conventional curable resin compositions, and has a low curing temperature, short curing time, excellent heat resistance and thermal stability, and excellent mechanical properties. The purpose is to provide a polyimide resin composition.

[Means to solve the problem]

The present inventors have discovered that a curable resin composition consisting of a maleimide compound and a vinylbenzyl ether compound bonded to an aromatic residue is effective, and has already been published in JP-A-64
-65110, but after further research,
We have discovered a curable resin composition that has excellent heat resistance such as hot strength.

That is, the composition of the present invention is a curable resin composition comprising (A) a compound having a maleimide group in the molecule, and (B) an N-substituted cycloaliphatic amine having two or more N-vinylbenzyl groups in the molecule. Compared to the invention of JP-A No. 84-65110, it can be cured at a similar low temperature, has a shorter curing time, and has even better thermal stability and mechanical properties, especially hot strength. The present invention provides a curable resin composition.

The present invention will be explained in more detail below.

Examples of the compound (A) having a maleimide group in the molecule which is a component of the composition of the present invention include N,N'-phenylene bismaleimide, N,N'-xylene bismaleimide, N,
N'-)-rylene bismaleimide, N,N'-diphenylmethane bismaleimide, N,N'-diphenyl ether bismaleimide-N,N'-dipheny! Bismaleimides such as resulfone bismaleimide, N,N'-diphenylmethane bismethylmaleimide, N,N'-diphenyl ether and smethylmaleimide, or the above-mentioned bismaleimides such as diaminodiphenylmethane, diaminodiphenyl sulfone, and diaminodiphenyl ether. Typical examples include compounds with an amino compound or an amine compound modified with an epoxy resin, which still have two maleimide groups in the molecule.

Furthermore, monofunctional maleimide compounds such as aromatic maleimides such as phenylmaleimide, alicyclic maleimides such as cyclohexylmaleimide, and alkylmaleimides such as laurylmaleimide can also be used, but they are preferably used in place of a part of the bismaleimide compound. be able to.

In addition, N-
The N-substituted cycloaliphatic amine having two or more vinylbenzyl groups is -Funazo (I) X-(C1]2-@-CH=CH2).

(In the formula, X represents a residue obtained by removing y hydrogen atoms from the amino group of a cycloaliphatic amine, and in the formula, y has a value of 2 to 6.)

- Typical cycloaliphatic amines that are raw materials in stock (I) are piperazine, N-aminoethylpiperazine, menthene diamine, isophorone diamine, bis(4-amino-3-methyldicyclohexyl)methane, diamino Dicyclohexylmethane, bis(aminomethyl)cyclohexane, 3,9-bis(3-aminopropyl)2,4,8
．． 10-tetraoxaspiro(5,5)undecane,
1-C2'-(2''-aminoethylamino)ethylcopiperazine, 1-(2'-(2''-aminoethylamino)ethyl)4-(2'-aminoethyl)piperazine, to 1,4-diazacyclo Butane, 1.5-diazacyclooctane, 1.9-diazacyclohexadecane, 1.
Examples include 10-diazacyclooctadecane, 1,11-diazacycloeicosane, 1,4,11.14-tetraazacycloeicosane, amine-terminated polybutadiene acrylonitrile (Gutdrich, Hiker ^TBN), etc. .

N-substituted cycloaliphatic amine (B
) can be easily obtained by adding, for example, a commercially available chloromethylstyrene monomer to the cycloaliphatic amine at a ratio of 2 to 6 vinylbenzyl groups, and dehydrochlorinating with an inorganic alkali using dimethyl sulfoxide as a solvent. can be synthesized into

The composition ratio of the maleimide compound (A) and the N-vinylbenzyl cycloaliphatic amine (B) in the present invention can be varied widely depending on the purpose of use.

When expressed as the equivalent ratio of each unsaturated group, A/B100/3
0~1/100. Preferably 100150 to 1/30
Good. Within this range, thermal curing is easy without intentionally adding a radical initiator necessary for curing, and the reaction proceeds at a much lower temperature and in a shorter time than in thermal curing alone. The temperature at which thermal decomposition starts is high and the decomposition loss is small.

The curable resin composition of the present invention comprises components (A) and (B).
In addition, known monomers such as styrene, vinyltoluene, allylphenol, allyloxybenzene, diallyl phthalate, acrylic ester, methicrylic ester,
Alternatively, vinyl ester resin, vinyl pyrrolidone, etc., typified by a reaction product of epoxy resin and (meth)acrylic acid, can be blended. In order to adjust the curing, hydroquinone, benzoquinone, copper salt, ammonium salt or aluminum salt of N-nitrosophenylhydroxylamine, etc. may be blended, and in order to accelerate the curing, known and publicly available radical initiators, such as Organic peroxides or an organic peroxide and its decomposition accelerator (REDOX) can also be blended.

Furthermore, the curable resin composition of the present invention can be cured by active energy rays such as ultraviolet rays and laser beams by incorporating a known and publicly used photoinitiator, and can also be easily cured by electron beams.

The curable resin composition of the present invention includes Neegu, Blengu,
Various other fillers and reinforcing fibers are prepared using rolls, etc., and dissolved in molding materials, composite materials, and solvents to create surfaces, paints, adhesives, and reinforcing fibers such as glass fibers, carbon fibers, and aromatic polyamides. It can be impregnated into fibers, silicon carbide fibers, and alumina fibres, making it a useful molding and structural material in handlay assemblies, prepregs, and filament windings.

〔Example〕

The present invention will be further explained below with reference to Examples.

In addition, unless otherwise specified, parts in the examples are parts by weight.

To a solution of 43.1 parts (1.0 equivalents) of anhydrous piperazine in 150 parts of dimethyl sulfoxide, 152.5 parts (1.0 equivalents) of commercially available chloromethylstyrene to which 500 pps+ of hydroquinone had been added was added at 60 to 70°C. After dropping for 10 minutes, add 70 to 80 parts of potassium hydroxide aqueous solution [56.1 parts (1.0 equivalents) of potassium hydroxide, 35 parts of water].
The mixture was added dropwise at 75° C. over 1 hour, and the reaction was further continued at 75° C. for 4 hours.

Next, a large excess of water was added to the system, the condensate and dimethyl sulfoxide were removed by stirring, and the oil was extracted with benzene. The benzene layer was washed repeatedly with water until the pH of the aqueous layer reached 7.
Benzene was removed under reduced pressure to obtain N,N'-divinylbenzylbeverazine (hereinafter referred to as N-DVBP) as an oil in a yield of 96%. Furthermore, the same synthesis is possible by using dioxane or N,N-dimethylformamide instead of the dimethyl sulfoxide used here.

In a similar manner, N-vinylbenzylamines were synthesized using N-aminoethylpiperazine instead of piperazine (hereinafter referred to as N-TVBAEP).

Table 1 shows the properties of each N-vinylbenzylamine. Each N-vinylbenzylamine was soluble in various organic solvents such as benzene, toluene, acetone, and MEK.

358 parts of N,N'-diphenylmethane bismaleimide (
1.0 mol) and 99 parts of diaminodiphenylmethane (
0.5 mol) was thoroughly ground and mixed in a ball mill, melted and stirred in a container at 170° C. for 10 minutes, and the container was immediately cooled with water to obtain a solid.

This reactant was soluble in solvents such as N-methylpyrrolidone and dimethylformamide, and was also soluble in low-boiling point solvents such as acetone and methylethylcarbonate (hereinafter referred to as
DDM modified BMI).

Reference flil for January 1, 2018
Diphenylmethane bismaleimide manufactured by Mitsui Toatsu (hereinafter referred to as BMI) 1 for each equivalent of VBAEP
Samples were prepared by mixing equivalent amounts, and these were placed on a hot plate at 120°C to examine gelation. For comparison, the same tests were conducted for each N-vinylbenzylamine and BMI. The results are shown in Table-2.

, thermal decomposition start temperature in air, JIS K6
The bending strength and bending elastic modulus at room temperature and hot condition were measured using a 911 method. The results are shown in Tables 3 and 4.

1 of each of N-DVBP' and N-TVBAEP.
A sample in which 1.0 equivalent of BMI was blended with respect to 0 equivalent and the DDM modified BMI synthesized in Reference Example 2 were blended in a theoretical equivalent of 10 equivalent, and molded at 120° C. for 30 minutes.

Temperature ratio W at 5% weight loss at a heating rate of 0°C/min After curing at 250°C for 5 hours after demolding A curable composition comprising a vinylbenzyl ether compound bonded with a group (JP-A-64-6511
As an example of No. 0), for 1 equivalent of bisphenol A divinylbenzyl ether (BADVBE), Example 1
The BMI used in Example 2 or the DDM-modified BMI synthesized in Reference Example 2 were each mixed in an amount of 1.0 equivalent theoretically.
Molding was carried out at 80°C for 30 minutes. Subsequently, the material was post-cured at 250° C. for 5 hours, and its bending strength and bending elastic modulus at room temperature and hot temperature were measured according to JIS K 6911.

The results are also shown in Table 4.

〔Effect of the invention〕

The curable resin composition according to the present invention is amorphous and has a low viscosity due to the above-mentioned structure, so it has excellent workability, and also exhibits excellent low-temperature curability, heat resistance, and mechanical strength. It can be widely used in industry as adhesive, casting, coating, impregnating, laminating molding compounds, or as paints, insulating materials or composite structural materials.

Patent applicant: Showa Kobunshi Co., Ltd. 112 no Procedural amendment July 10, 1990

Claims (1)

[Claims] (A) A compound having a maleimide group in the molecule, and (B
) A curable resin composition comprising an N-substituted cycloaliphatic amine having two or more N-vinylbenzyl groups in the molecule.