JP2856537B2 - Curable resin composition - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a curable polymaleimide resin composition. In particular, the present invention relates to a curable resin composition excellent in low-temperature curing, heat resistance, and mechanical properties.

[Conventional technology]

The curable composition is bonded, cast, coated, impregnated,
It is widely used in coatings, insulating materials, composite structural materials and the like as lamination and molding compounds.

Among them, a polyimide resin is one of the most excellent materials, and various developments have been promoted. For example, a composition of a polymaleimide compound and a reactive oligomer having an alkenyl ether at the terminal of the molecule is known from JP-A-62-53319.

[Problems to be solved by the invention]

However, the above-mentioned resin composition has a high curing temperature and a long curing time, and is not advantageous in terms of workability including these, as compared with existing general-purpose curable resins. Further, in recent years, curable resins have been used in a wide variety of applications, and curable resin compositions conventionally used are not all satisfactory in various use environments or conditions. In particular, the heat resistance when the use temperature is high, the hot strength is not sufficient, and even in the most typical composition such as a combination of a conventionally known bismaleimide, an aromatic amine and an epoxy resin, it is still insufficient. Material was not provided.

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

The present inventors have found that a curable resin composition comprising a maleimide compound and a vinyl benzyl ether compound bonded to an aromatic residue is effective,
No.-65110 was proposed, but further research was conducted to find a curable resin composition having excellent heat resistance such as hot strength.

[Means for solving the problem]

That is, the present invention provides a curable resin composition comprising a compound having a maleimide group in the molecule and divinylbenzyl ether, and can be cured at a low temperature similar to the invention of JP-A-64-65110. An object of the present invention is to provide a curable resin composition characterized by having a shorter time and further excellent thermal stability and mechanical properties, especially excellent hot strength.

 Hereinafter, the present invention will be described in more detail.

(Compound Having Maleimide Group in Molecule) The compound having a maleimide group in the molecule, which is one component of the composition of the present invention, includes, for example, N, N′-phenylenebismaleimide, N, N′-xylenebismaleimide, N, N'-tolylenebismaleimide, N, N'-diphenylmethanebismaleimide, N, N'-diphenyletherbismaleimide, N, N'-diphenylsulfonebismaleimide, N, N '
Bismaleimides such as diphenylmethane bismethylmaleimide, N, N'-diphenylether bismethylmaleimide, or amino obtained by modifying the above bismaleimides with an amino compound such as diaminodiphenylmethane, diaminodiphenylsulfone, and diaminodiphenylether or an epoxy resin As an adduct with a compound, a compound which still has two maleimide groups in the molecule can be exemplified.

Monofunctional maleimide compounds such as aromatic maleimides such as phenylmaleimide and alicyclic maleimides such as cyclohexylmaleimide and alkylmaleimides such as laurylmaleimide can also be used. it can.

(Divinylbenzyl ether) Another component of the composition of the present invention, divinylbenzylether, has the following general formula Can be represented by

The divinylbenzyl ether represented by the above general formula can be easily synthesized by using a commercially available chloromethylstyrene monomer and dehydrochlorinating with an aqueous inorganic alkyl solution.

(Composition) In the present invention, the composition ratio of the maleimide compound and divinylbenzyl ether can be varied widely depending on the purpose of use. In terms of the equivalent ratio of each unsaturated group, maleimide compound / divinylbenzyl ether = 10
0/30 to 1/100, preferably 100/50 to 1/30. Within this range, even if the radical initiator required for curing is not intentionally added, the composition is easily thermoset, and the reaction proceeds at a much lower temperature and in a shorter time as compared with each case of thermosetting alone.
The onset temperature of thermal decomposition in air is high and the decomposition loss is small.

The curable resin composition of the present invention comprises a maleimide compound and divinylbenzyl ether, and a known monomer such as styrene, vinyltoluene, allylphenol, allyloxybenzene, diallylphthalate, acrylate, methacrylate, or epoxy resin. Ester resins, vinylpyrrolidone, vinylbenzyl ether compounds obtained by reacting phenols with chloromethylstyrene, and amine compounds obtained by reacting chloromethylstyrene Vinylbenzylamine compound or the like can be blended. For the preparation of curing, hydroquinone, benzoquinone, copper salt, ammonium salt or aluminum salt of N-nitrosophenylhydroxylamine, etc. may be blended.In order to further promote curing, a known and used radical initiator, for example, Organic peroxides or an organic peroxide and its decomposition accelerator (BEDOX) can be blended.

The curable resin composition of the present invention can be cured with an active energy ray such as an ultraviolet ray or a laser beam, and can be easily cured with an electron beam by adding a known and publicly-known photoinitiator.

The curable resin composition of the present invention can be formed into a molding material or a composite material by blending other various fillers and reinforcing fibers with a kneader, a blender, a roll, or the like. In addition, it can be dissolved in a solvent to form a varnish, a paint, an adhesive, and impregnated into reinforcing fibers such as glass fiber, carbon fiber, aromatic polyamide fiber, silicon carbide fiber, and alumina fiber, and hand lay-up molding, As prepregs and also filament windings, they can be useful molding and structural materials.

〔Example〕

Hereinafter, the present invention will be further described with reference to examples. In addition,
Unless otherwise specified, parts in the examples are parts by weight.

Reference Example 1 Synthesis of divinylbenzyl ether (hereinafter abbreviated as DVBE) Commercially available chloromethylstyrene 15 to which 300 ppm of aluminum salt of N-nitrosophenylhydroxylamine was added.
2.5 parts (1.0 equivalent) of dimethyl sulfoxide (DMSO) 150
An aqueous solution of potassium hydroxide [67.3 parts (1.2 equivalents) of potassium hydroxide, 35 parts of water] was added dropwise at 60 ± 2 ° C. over a period of 40 minutes, and the reaction was continued at 60 ± 2 ° C. for 4 hours. .

Next, a large excess of water was added to the system, and after stirring, water-DMSO was removed, and an oil was extracted with benzene. The benzene layer was repeatedly washed with water until the pH of the aqueous layer became 7, and benzene was removed under reduced pressure to obtain DVBE having a viscosity of 0.1 (ps / 25 ° C.) in a yield of 98%.
Also, dioxane or N, instead of DMSO used here
Similarly, synthesis was possible using N-dimethylformamide.

Reference Example 2 Synthesis of diaminodiphenylmethane-modified bismaleimide by reaction of bismaleimide and diaminodiphenylmethane 358 parts (1.0 mol) of N—N′-diphenylmethanebismaleimide and 99 parts of diaminodiphenylmethane (0.5 part)
Mol) was sufficiently pulverized and mixed with a ball mill at 170 ° C.
Was melt-stirred in the vessel for 10 minutes, and the vessel was immediately cooled with water to obtain a solid. This reaction product was soluble in solvents such as N-methylpyrrolidone and dimethylformamide, and was also soluble in low boiling solvents such as acetone and methyl ethyl ketone (hereinafter referred to as DDM-modified BMI).

Example 1 Mitsui Toatsu's diphenylmethane bismaleimide (hereinafter abbreviated as BMI) 1 per equivalent of DVBE synthesized in Reference Example 1
Samples were prepared by mixing the equivalent amounts, and these were placed on a hot plate at 120 ° C. and examined for gelation. DVBE, BM for comparison
The same test was performed for I. The results are shown in Table 1.

Example 2 A sample prepared by mixing 1.0 equivalent of BMI with respect to 1.0 equivalent of DVBE and 1.0 equivalent of the DDM-modified BMI synthesized in Reference Example 2 in theoretical equivalent were molded at 120 ° C. for 30 minutes. After the mold was released, the composition was further cured at 250 ° C. for 5 hours, and the thermal decomposition initiation temperature in air, the bending strength at normal temperature and hot temperature according to JIS K 6911, and the bending elastic modulus were measured. The results are shown in Tables 2 and 3.

Comparative Example 1 As a comparison, a curable composition comprising a vinyl benzyl ether compound in which a maleimide compound and an aromatic residue are combined as previously proposed by the present inventors (JP-A-64-65110)
As an example of (1), 1 equivalent of bisphenol A divinylbenzyl ether (BADVBE) was mixed with 1.0 equivalent of the theoretical equivalent of the BMI used in Example 1 or the DDM-modified BMI synthesized in Reference Example 2, respectively. Molding was performed at 180 ° C. for 30 minutes. Then, after post-curing at 250 ° C for 5 hours,
The flexural strength and flexural modulus at room temperature and hot temperature were measured by IS K 6911. The results are also shown in Table-3.

[Effect of the Invention] The curable resin composition according to the present invention is, because of the above-mentioned constitution, amorphous and low in viscosity, and excellent in workability,
It has excellent low-temperature curability, heat resistance and mechanical strength, so it can be widely used in industry as an adhesive, casting, coating, impregnating, laminating compound, or as a paint, insulating material or composite structural material. Can be.

Continuation of front page (56) References JP-A-1-65110 (JP, A) JP-A-2-88609 (JP, A) JP-A-1-201310 (JP, A) JP-A-4-31412 (JP) JP-A-3-290414 (JP, A) JP-A-4-31409 (JP, A) JP-A-4-31410 (JP, A) JP-A-4-31411 (JP, A) JP-A-3-20312 (JP, A) JP-A-3-281512 (JP, A) JP-A-3-70716 (JP, A) JP-A-2-113006 (JP, A) WO 91/2013 (WO, A1) (58) Investigated field (Int.Cl. ⁶ , DB name) C08F 12/00-12/36 C08F 112/00-112/36 C08F 212/00-212/36 C08F 22/00-22/40 C08F 122/00-122/40 C08F 222/00-222/40 C08F 290/00-290/14 C09D 4/00-4/06 C09J 4/00-4/06

Claims (1)

(57) [Claims] 1. A curable resin composition comprising a compound having a maleimide group in a molecule and divinylbenzyl ether.