JPH0623196B2 - Diacetylene group-containing imide compound having terminal double bond - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention relates to a diacetylene group-containing imide compound which is easily cured at a low temperature to give an excellent heat-resistant cured product.

[Conventional technology and its problems]

Conventionally, thermosetting resins have been used as adhesives, coating materials, sealants, potting materials, base materials for fiber reinforced materials, etc., but in such fields, they cure at low temperatures and have high heat resistance. Since the material that can be expressed is not yet fully developed, various studies have been made.

In this way, among various studies, a polyimide compound of a type that cures by an addition reaction, that is, PMR
(NASA) and Kelimide (Rhone Poulenc) have been developed and are commercially available.

However, PMR is relatively good in terms of heat resistance, but has problems such as high curing temperature and long curing time. On the other hand, kelimide has low curing temperature but insufficient heat resistance. As described above, the balance between curability and heat resistance has not been sufficiently satisfied by the conventional techniques.

Further, in recent years, studies have been made to utilize the acetylene bond in the crosslinking reaction, but even in this case, there are problems such as a high curing temperature and a long curing time. The current situation is that they cannot pull out.

[Means for solving problems]

The present inventors have conducted various studies on the reactivity of acetylene compounds, and in particular, have focused on the reactivity of diacetylene bonds. In the process, it was found that a diacetylene bond easily reacts with a certain double bond at a low temperature, and as a result of further earnest research, the present invention was reached.

That is, the present invention is a diacetylene group-containing imide compound having a terminal double bond represented by the following general formula Structural Formula I.

(Where R is X is an organic group having a double bond selected from
CH ₂ - or Is. ) Is.

The diacetylene group-containing imide compound of the present invention has a diacetylene bond and a specific double bond in one molecule of the compound,
In addition, it is a compound in which these bonds are connected by an imide group. Due to such a special chemical structure, when it is heated, it can be easily cured at a low temperature, and a cured product excellent in heat resistance can be obtained.

In the present invention, R is And X is —CH ₂ — or (Including ortho and meta positions).

In order to produce the diacetylene compound of the present invention, it can be synthesized by devising a known organic chemical reaction.
For example, to prepare a compound of general structural formula I: By a dehydration reaction between an acid anhydride represented by and an acetylene-based amino compound represented by H ₂ NX-CH≡CH (where X represents a linking group), By synthesizing an acetylene imide compound represented by There is a method of synthesizing a diacetylene group-containing imide compound represented by

〔The invention's effect〕

The diacetylene group-containing imide compound of the present invention has a temperature of 300 ° C.
Hereinafter, for example, a material that can complete a crosslinking reaction within a short time even at a temperature of about 250 ° C. or lower, or 100 ° C. or lower depending on the selection of the compound, and the obtained cured product generally shows a thermogravimetric analysis in air. Shows a very good heat resistance with almost no decrease even at 300 ° C or higher, and depending on the compound, even at 400 ° C or higher.

Further, the mechanical properties of the molded product, for example, good physical properties of the elastic modulus can be obtained, while the general organic polymer has an elastic modulus of 1 to 3 GPa, a molded product using the diacetylene compound of the present invention Can easily develop an elastic modulus of 3 GPa or more.

Such excellent crosslinkability is considered to be due to mutual crosslinkage between a diacetylene bond and a specific double bond in one molecule, and details thereof have not yet been sufficiently understood.

In addition, the present diacetylene group-containing imide compound can be melted, has excellent solubility in a solvent, and the like. It can be used in a shape, and can be used by mixing with selfless or organic fibrous material, powdery material, flaky material, other curable resin or polymer material, coloring material or stabilizing material, etc. It can be used by mixing with, and can be used as coating materials, adhesives, base materials for fiber reinforced materials, sealants, potting materials, etc., and hardened materials of various shapes such as plate-shaped and sheet-shaped materials. It is extremely useful to obtain it.

〔Example〕

Example 1 Anhydrous-5-norbornene-2,3-dicarboxylic acid 0.165mol
(27.06 g) and 0.165 mol (9.1 g) of propargylamine were reacted in acetic acid while refluxing acetic acid. After the reaction, half the amount of acetic acid was taken out of the system, cooled, and then poured into water. After the precipitation was over, the precipitate was washed with water until the odor of acetic acid disappeared, repeated over and dried under reduced pressure (Product A). Next, while bubbling oxygen into a flask containing a solution of 0.008 mol (0.8 g) of cuprous chloride dissolved in pyridine, a solution of 16.08 g of product A in pyridine was added dropwise for reaction. After the reaction, the solution was poured into water and a precipitate formed. After washing with water and repeating the process, the residue was dried under reduced pressure to obtain 14 g (87.9% of theory) of a pale yellow powder.

The melting point of this product was 190 to 193 ° C, and the analytical values were as follows.

Theoretical value as C ₂₄ H ₂₀ O ₄ N ₂ C 72.0, H 5.0, N 7.0, O 16.0 Measured value C 72.0, H 4.5, N 6.8, O 16.7 Also, the characteristic absorption of IR absorption spectrum is -C≡C-2170cm. ^-1 ,
The imide five-membered ring was 1770 cm ^-1 and 1720 cm ^-1 . The absorption spectrum is shown in FIG.

On the other hand, it has excellent solubility in a solvent, and was dissolved in acetone at room temperature, and in methanol, ethanol, and ethyl acetate with some heating.

When this product was heated, it began to melt at 190 ° C, began to cure at about 210 ° C, and was completely cured at about 250 ° C. If it is kept at 210 ° C for 5 minutes, it will be completely cured and will be 200 ° C
Then it was cured in 10 minutes. When the thermogravimetric analysis of this cured product was carried out in air, as shown in 1 in FIG.
The heat resistance is much higher than that of 3 and 4 in FIG.

Further, the effect of temperature on the curing was measured by differential analysis, and it was found that an exothermic reaction for curing occurs at a much lower temperature than that in 3 in FIG. 4 as shown by 1 in FIG.

Comparative Example 1 As a material having a diacetylene bond but no specific double bond, phthalic anhydride was used as an acid anhydride for the purpose of comparison with Example 1, and the compound was synthesized in the same manner as in Example 1 to give a pale yellow color. 79.9 g (87.2% of theory) of powder were obtained.

The melting point of this product was 262 to 265 ° C., and the analytical values were as follows.

Theoretical value as C ₂₂ H ₁₂ O ₄ N ₂ C 71.7, H 3.3, N 7.6, O 17.4 Measured value C 72.1, H 3.1, N 6.9, O 17.4 Also, the characteristic absorption of IR absorption spectrum is -C≡C-2140cm. ^-1 ,
The imide five-membered ring was 1770 cm ⁻¹ and 1730 cm ⁻¹ .

On the other hand, the solubility was that it did not dissolve in acetone, methanol, ethanol, benzene, toluene, xylene, and ethyl acetate even when heated, and it dissolved in chloroform when heated at a low concentration. As mentioned above, the solubility is poor.

The product was heated and melted and cured at about 260 ° C. When the thermogravimetric analysis of this cured product was carried out in air, the weight loss was 5% at 325 ° C. as shown in FIG. In FIG. 4, curing with respect to temperature is shown by its exotherm by differential thermal analysis.

Comparative example 2 An experiment was carried out for comparison as a compound having a double bond but no diacetylene bond.

5-Norbornene-2,3-dicarboxylic acid anhydride 0.5 mol (8
2 g) and 0.25 mol (27 g) of p-phenylenediamine were reacted in acetic acid while refluxing acetic acid. After the reaction, half the amount of acetic acid was taken out of the system, cooled, and then poured into water. After the precipitation was completed, the precipitate was washed with water and repeated, and dried under reduced pressure to obtain 96.3 g (96.3% of the theoretical value) of pale pink crystals.

The melting point of this product was 300 ° C. or higher, and the analytical values were as follows.

Theoretical value for C ₂₂ H ₁₅ O ₄ N ₂ is C 72.0, H 5.0, N 7.0, O 16.0. Measured value C 71.7, H 4.9, N 6.5, O 17.5.
72cm ^-1, it was 1725cm ^-1.

Regarding the solubility in a solvent, it did not dissolve in acetone and methanol even when heated, but it did dissolve in chloroform when heated.

When this product was heated, it did not melt up to 300 ° C,
No change was seen in the appearance. The result of thermogravimetric analysis in air showed a 10% weight loss at 320 ° C. as shown in FIG.

Example 2 As an acid anhydride, cis-4-cyclohexene-1,2-dicarboxylic acid anhydride was used in place of 5-norbornene-2,3-dicarboxylic acid anhydride, and was synthesized in the same manner as in Example 1 to obtain 36.8 g of white powder. (97.9% of theory) was obtained.

The melting point of this product was 198 to 200 ° C, and the analytical values were as follows.

Theoretical value as C ₂₄ H ₂₄ O ₄ N ₂ C 70.2, H 5.3, O 17.1, N 7.4 Measured value C 69.2, H 5.4, O 17.7, N 7.0 Also, the characteristic absorption of IR absorption spectrum is -C≡C-2140cm. ^-1 ,
The imide five-membered ring was 1770 cm ⁻¹ and 1706 cm ⁻¹ . The absorption spectrum is shown in FIG.

On the other hand, it has excellent solubility in a solvent and was dissolved in acetone at room temperature.

When this product was heated, it began to melt at 195 ° C, began to cure at about 210 ° C, and was completely cured at about 250 ° C. The hardening versus temperature is shown in FIG. 4 by its exotherm by differential thermal analysis.

When the thermogravimetric analysis of this cured product was measured in air, the weight loss was only 3% at 410 ° C. as shown in FIG.

Example 3 A pale yellow powder 2 was obtained by the method of Example 1 using anhydrous-5-norbornene-2,3-dicarboxylic acid and aminophenylacetylene obtained by the method of JP-A-54-122242.
0 g (77% of theory) were obtained.

The product did not melt up to 300 ° C. The analytical values were as follows.

Theoretical value as C ₃₄ H ₂₄ O ₄ N ₂ C 77.9, H 4.6, O 12.2, N 5.3 Measured value C 78.0, H 5.0, O 11.8, N 5.1 Also, the characteristic absorption of the IR absorption spectrum is -C≡C- 2145c
m ^-1 , the five-membered imide ring was 1770 cm ^-1 , 1715 cm ^-1 .

Thermogravimetric analysis of this product was carried out in air, and
The weight loss was only 1% at 70 ° C.

Reference Example 1 The compound of Example 1 was subjected to compression molding at 300 ° C. under a pressure of 200 kg / cm ² for 7 minutes to obtain a plate-shaped material having a thickness of 0.670 mm. The density of this plate-like product was 1.324, and when thermogravimetric analysis was performed in air, the weight loss was only 2% even at 450 ° C., and the heat resistance was very good.

The flexural modulus of this plate was measured and found to be about 3 GPa.
And was good.

Reference Example 2 The powder of the compound of Example 1 was coated on a steel plate and 220
Melting and curing were carried out at 0 ° C. for 2 minutes to obtain a coating film having a thickness of about 150 μm. When a pencil scratch test was conducted on this coating film, the pencil scratch value was H, which was a good value. When a similar test was performed on a coating film which was further cured at 220 ° C. for 10 minutes, the pencil scratch value was as good as 2H. When this coating film was peeled from the steel sheet and subjected to thermogravimetric analysis in air, the weight loss was only 1.8% even at 450 ° C. and the heat resistance was very good.

[Brief description of drawings]

FIG. 1 is an infrared absorption spectrum chart of the compound of Example 1 according to the present invention. FIG. 2 is an infrared absorption spectrum diagram of the compound of Example 2 according to the present invention. FIG. 3 is a diagram showing the results of thermogravimetric analysis comparing the thermal stability of a cured product of the product of the present invention with that of a comparative example. Among them, 1 is Example 1, 2 is Example 2, 3 is Comparative Example 1, and 4 is Comparative Example 2. FIG. 4 is a diagram showing the curing of the product according to the present invention by a differential thermal analysis by its exothermic phenomenon.

Claims (1)

[Claims] 1. A diacetylene group-containing imide compound having a terminal double bond represented by the following general formula Structural Formula I. (Where R is X is an organic group having a double bond selected from
CH ₂ - or Is. )