JPS63154684A - Bismaleimide containing pyridine ring and production thereof - Google Patents

Abstract

NEW MATERIAL:2,6-Bis(4-maleimidophenoxy)pyridine of formula I. USE:A main raw material for polyaminobismaleimide resin. It has excellent heat-resistance. The compound is also expected to be effective in improving the adhesivity taking advantage of affinity with metals as well as improving the moldability, flexibility and electrical conductivity. PREPARATION:2,6-Bis(4-aminophenoxy)pyridine of formula II is made to react with maleic anhydride in preferably 1-10 times weight of an organic solvent (e.g. chloroform, acetone, THF, etc.) at 20-80 deg.C for 0.5-9hr.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to bismaleimide useful as a monomer for heat-resistant polymers and a method for producing the same.

More specifically, 2,6-bis(4-maleimidophenoxy) represented by formula (1)
and lysine and this compound represented by formula (2) 2,6
-Relates to a method for producing by reacting bis(4-aminophenoxy)pyridine and maleic anhydride.

The compound of the present invention has not been produced in the past and has no known uses. However, similar to conventional bismaleimide compounds typified by N,N'-bis(4,4''-methylene diphenylene) bismaleimide, polymaleimide-based resins and polyaminobismaleimide-based resins are produced using the terminal double bond. Can be used as a key raw material for resin.

[Prior art]

Conventionally, resins having an imide structure have exhibited excellent performance in electrical insulation, heat resistance, and dimensional stability of molded products, and have been widely used in industry. For example, polyimide resins, polyamino bismaleimide resins, and the like are known as heat-resistant thermosetting resins used in electrical insulating materials, and are widely used in impregnated varnishes, laminates, molded products, and the like.

On the other hand, the present inventors have found that a strong film can be obtained from a polyimide resin obtained by condensing the diamine represented by the formula (2), which is a raw material for the compound of the present invention, with benzophenone tetracarboxylic dianhydride. It was discovered that the material exhibited high heat resistance, and an application was previously filed (Japanese Patent Application No. 6O-276878).

Bismaleimide compounds have conventionally contained a benzene-based aromatic compound as a main skeleton, and compounds having a heterocyclic compound in the molecule are hardly known. However, since the bismaleimide compound containing a pyridine ring of the present invention has a lone pair of electrons on the nitrogen atom, the polyamino bismaleimide resin using it has not only inherent heat resistance but also metal ion It is expected that adhesiveness will be improved by utilizing the affinity with metal ions, and conductivity will be improved by doping with metal ions.

[Problem that the invention seeks to solve]

An object of the present invention is to provide a heat-resistant bismaleimide compound containing a pyridine ring in the molecule represented by formula (1), and a method for producing the same.

[Means for solving problems]

Based on the above idea, the present inventors have made extensive studies to solve the problems of the present invention.

As a result, the novel bismaleimide compound represented by the above formula (1) has excellent heat resistance and can be easily reacted by condensation and dehydration of 2,6-bis(4-aminophenoxy)pyridine and maleic anhydride. The inventors have found that it is possible to produce the same, and have solved the problems of the present invention.

An example of a measure of heat resistance is 5% weight loss hot water temperature, and the value of the bismaleimide compound of the present invention is 428° C. (in air), which indicates that the heat resistance is at a sufficiently satisfactory level.

In addition, since the polyamino bismaleimide resin obtained by polymerizing the bismaleimide compound of the present invention contains a pyridine ring, it is expected to improve adhesiveness by utilizing its affinity with metal ions and conductivity by doping with metal ions. can.

Next, the method for producing the compound of the present invention is as follows.

The diamines used as raw materials are 1. It is 2,6-bis(4-aminophenoxy)pyridine represented by the above formula (2). This diamine can be easily produced industrially by reacting 2,6-dichloropyridine and 4-aminophenol in an aprotic polar solvent in the presence of a base (Japanese Patent Application No. 6O-276878 ).

The method for producing the compound of the present invention is not particularly limited, but
Usually, in the first step, the diamine represented by formula (2) and maleic anhydride are reacted in an organic solvent to produce bismaleamic acid represented by formula (3). Known methods are used for this purpose. Usually used anti-JilS
? The 9 solvents include halogenated hydrocarbons such as chloroform, methylene chloride, dichloroethane, and trichloroethylene, ketones such as acetone, methyl ethyl ketone, cyclohexanone, and diisopropyl ketone, ethers, ethers such as tetrahydrofuran, dioxane, and 2-methoxyethanol, benzene, toluene, Aromatic compounds such as chlorobenzene, acetonitrile, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, 1-methyl-2-pyrrolidinone, 11
Examples include aprotic polar solvents such as 3-dimethyl-2-imidazolidinone.

The amount of these solvents used is not particularly limited, but usually 1 to 10 times the weight of the raw materials is sufficient.

Next, in the second step, bismaleamic acid is cyclized and dehydrated to produce bismaleimide represented by formula (1).

This method uses acetic anhydride as a dehydrating agent and conducts the reaction in an organic solvent in the presence of a base and a catalyst (Japanese Patent Publications No. 46-23250, No. 49-40231, No. 59-52660). .

At this time, the amount of acetic anhydride used is not particularly limited as to the upper limit, but it is usually in the range of 2 to 4 times the molar amount of bismaleamic acid.

The catalysts used are alkaline earth metal oxides, iron (■
and I[L nickel (■), manganese (■ and I[
[), copper (I and ■) or cobalt (■ and ■)
carbonates, sulfates, phosphates, acetates, etc., and particularly preferred are nickel acetate (■), cobalt acetate (■),
Magnesium oxide (I[). These catalysts exhibit sufficient effects when used alone, but two or more types may be used in combination. The amount used is 5 Xl for bismaleamic acid.
It is in the range of 0-' to 0.1 mole. The base used is
It is an alkali metal acetate or a tertiary amine. Specific examples include sodium acetate, potassium acetate, trimethylamine, triethylamine, and tributylamine. The amount used is in the range of 0.05 to 1.1 mol based on bismaleamic acid.

There are no particular limitations when implementing the method of the present invention;
The intermediate bismaleamic acid produced in this step does not necessarily need to be isolated in order to produce bismaleimide, and can be directly subjected to the second step cyclization and dehydration reaction in the same solvent. At this time, the reaction temperature is in the range of 20 to 80''C, and the reaction time is in the range of 0.5 to 9 hours.

After the reaction is completed, the precipitated crystals are filtered or discharged into water or methanol to obtain crystals of the desired product.

[Action and effect]

The compound of the present invention is a bismaleimide compound having excellent heat resistance. In addition, the polyamino bismaleimide resin using the compound of the present invention has a structure that has a pyridine ring and an ether bond in the molecule, and has excellent adhesion, moldability, flexibility, and metal ion properties using its affinity with metals. Since conductivity can be expected to improve by doping with , it is also useful as a material that requires unique functions.

Example 1 A reaction flask equipped with a stirrer and a thermometer was charged with 43.2 g (0.44 mol) of maleic anhydride and 130 g of acetone and dissolved therein. To this, 58.6 g (0.2 mol) of 2,6-bis(4-aminophenoxy)pyridine was added to 3 mol of acetone.
A solution dissolved in 52 g was added dropwise at room temperature, and further 23 to 27
Stir at °C for 3 hours.

After the reaction was completed, the resulting crystals were filtered, washed with acetone, and dried to obtain bismaleamic acid as yellow crystals.

Yield 97.0g (yield 99.0%) m, p 30
Elemental analysis above 0'C CHN Calculated value (χ) 61.35 3.91 8.59
Analysis value (χ) 61.49 3.84 8.59
IR (KBr, cm-'): 1690 (carbonyl group), 1230 (ether bond) 97.0 g of bismaleamic acid thus obtained was suspended in 294 g of acetone, and triethylamine 9.6 g was suspended in 294 g of acetone.
g and stir for 30 minutes at room temperature.

Magnesium oxide (I[) 0.4g, gobalt acetate (■
)・4H2OO, after adding 04g, acetic anhydride 52.0
g at 25°C over 30 minutes, and then at 55°C for 2 hours.
Stir for an hour.

After the reaction was completed, the produced crystals were filtered, washed, and dried to obtain bismaleimide as yellow crystals.

Yield 80.0g (yield 88.2%) m, p 22
0~223°C Elemental analysis CHN Calculated value (χ”) 66.23 3.33 9.2
7 Analysis value (%) 66.40 2.92 8.9
5IR (KBr, cm-'): 1710 and 17
60 (imide bond), 1220 (ether bond) 5% weight loss Hot water temperature (in air): 428°C Example 2 43.2 g of maleic anhydride (0,44 mol) and 100 g of acetone are charged and dissolved. A solution of 58.6 g (0.2 mol) of 2,6-bis(4-aminophenoxy)pyridine dissolved in 200 g was added dropwise to this at room temperature, and then heated to 23-27°C for 3 hours.
After stirring for a while, yellow crystals begin to precipitate. Add 9.6 g of triethylamine to this and stir at room temperature for 30 minutes.

Magnesium (II) oxide 0.4g, cobalt acetate (■
)・4Ht0 After adding 0.04 g, acetic anhydride 52.
0g was added dropwise at 25°C over 30 minutes, and then at 55°C for 2 hours.
Stir for an hour.

After the reaction was completed, the produced crystals were filtered, washed with acetone, and dried to obtain bismaleimide as yellow crystals.

Yield: 84.6g (yield 93%) Garden, p 220-223℃

Claims (1)

[Claims] 1) 2,6-bis(4-maleimidophenoxy) represented by formula (1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(1)
Pyridine 2) Formula (2) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(2) 2, which is characterized by reacting 2,6-bis(4-aminophenoxy)pyridine represented by formula (2) with maleic anhydride.
, 6-bis(4-maleimidophenoxy)pyridine production method.