JP2912711B2 - Method for producing polyamide-imide resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a novel polyamide-imide resin. More specifically, the present invention relates to a method for producing an aliphatic or aromatic polyamide-imide resin having excellent heat resistance and having a controlled molecular arrangement capable of injection molding.

[0002]

2. Description of the Related Art Generally, an aliphatic polyamide resin (nylon) is excellent in moldability but inferior in heat resistance. Therefore,
As an attempt to solve the drawbacks of these resins, aliphatic and aromatic polyamide resins having an aromatic ring introduced have been proposed. For example, JP-A-59-53536 proposes a polyamide resin comprising an aromatic dicarboxylic acid and an aliphatic diamine. Further, a polyamide resin formed from an aromatic carboxylic acid, adipic acid and an aliphatic diamine is also proposed in Japanese Patent Application Laid-Open No. Sho 59-155426. These resins can be melt-molded, but are not satisfactory with respect to heat resistance and the like.

On the other hand, as a method for improving the heat resistance, mechanical properties and the like of a polyamide resin, a polyamide-imide resin having an imide ring introduced has been proposed. For example, U.S. Pat. No. 3,939,029 discloses an aliphatic or aromatic polyamide-imide resin obtained by synthesizing a polyamic acid from trimellitic anhydride chloride and an aliphatic diamine and heating and dehydrating the polyamic acid. However, in such a resin production method, the reactivity of the aliphatic diamine is low with respect to anhydrous trimellitate chloride, so that only a low-molecular-weight one can be obtained. Was not of sufficient high molecular weight to be obtained.

[0004] In order to solve these problems, the present inventors have prepared a high-molecular-weight randomly arranged aliphatic or aromatic polyamide-imide resin having heat resistance and capable of injection molding in an earlier application. is suggesting. Although the polyamide resin arranged at random has excellent heat resistance, it has a problem that its performance is hardly exhibited in applications requiring more heat resistance.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a novel method for producing an aliphatic or aromatic polyamide-imide resin having excellent heat resistance and having a controlled molecular arrangement capable of injection molding. It is.

[0006]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that benzene-
Aliphatic and aromatic polyamides with controlled molecular arrangement obtained by polycondensation of aliphatic diisocyanate with diimide dicarboxylic acid obtained by condensation of 1,2,4-tricarboxylic anhydride and aliphatic diisocyanate The imide copolymer has been found to be suitable for the above purpose,
The present invention has been reached.

That is, the present invention relates to a method for producing a polyamideimide resin having a repeating unit represented by the above general formula (I) (formula 1), wherein 1 mol of benzene-1,2,4-tricarboxylic anhydride is added to 1 mol of benzene-1,2,4-tricarboxylic anhydride. OCNCH ₂ -R ₁ -CH ₂
The presence of an alkali metal compound diisocyanate 0.475 to 0.525 moles of NCO as catalyst, reacted in aprotic polar solvents in 100 to 25 ⁰⁰ C, further wherein OCNCH ₂ -
R ₂ —CH ₂ NCO diisocyanate 0.475 to 0.52
Another object of the present invention is to provide a method for producing a polyamideimide resin, which comprises adding 5 mol and conducting polycondensation at 150 ° C. or more to control the molecular arrangement. The control of the molecular arrangement in this case means that the diimide units generated in the first stage imidation and facing each other are regularly arranged via the amide bond generated in the second stage amidation reaction. Means.

In one embodiment of the present invention, one mole of benzene-1,2,4-tricarboxylic anhydride is used for producing a polyamideimide resin having a repeating unit represented by the general formula (II) (Formula 2). The reaction was carried out in an aprotic polar solvent at 100 to 250 ° C in the presence of an alkali metal compound using 0.475 to 0.525 mol of metaxylylene diisocyanate as a catalyst.
Production of polyamideimide resin by controlling the molecular arrangement by adding ~ 0.525 mol and conducting polycondensation at 150 ° C or higher.

The alkali metal compound is preferably an alkali metal polycarboxylate, an alkali metal carbonate, an alkali metal bicarbonate, an alkali metal hydroxide, or an alkali metal fluoride. The aprotic polar solvent is preferably a linear or cyclic amide, phosphorylamide, sulfone, sulfoxide or urea.

[0010] The benzene-1,2,4- used in the present invention
The molar ratio of tricarboxylic anhydride to metaxylylene diisocyanate is preferably in the range of 0.475 to 0.525, more preferably 0.49 to 0.51, per mole of benzene-1,2,4-tricarboxylic anhydride. If the molar ratio is less than 0.475 or exceeds 0.525, the amount of the intermediate diimidedicarboxylic acid produced is undesirably small. The molar ratio of the meta-xylylene diisocyanate to be added next is 0.475 to 0.525 to 1 mol of benzene-1,2,4-tricarboxylic anhydride.
Is more preferable, and the range of 0.49 to 0.51 is more preferable. If the molar ratio is less than 0.475 or more than 0.525, only low molecular weight polymers are obtained. Also, to control the molecular weight of the polymer, such as phthalic anhydride and benzoic acid,
A monoisocyanate such as an acid anhydride, a monocarboxylic acid, or phenylisocyanate may be added and reacted.

Examples of the alkali metal compound used as a catalyst in the process of the present invention include mono- and / or di- and / or tri- and / or tetralithium salts of dicarboxylic acids, tricarboxylic acids and tetracarboxylic acids.
Alkali metal salts of polyvalent carboxylic acids such as sodium salt, potassium salt, rubidium salt, cesium salt, and francium salt; alkali metal carbonates such as lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate, cesium carbonate, and furanium carbonate; Lithium hydrogen, sodium bicarbonate, potassium bicarbonate, rubidium bicarbonate, alkali metal bicarbonates such as cesium bicarbonate, francium bicarbonate, lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, Alkali metal hydroxides such as francium hydroxide, lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride,
Alkali metal fluorides such as cesium fluoride and furanium fluoride; Particularly, sodium salts and potassium salts are preferred. The above alkali metal compounds may be used alone or in combination of two or more.

The aprotic polar solvent used in the present invention includes, for example, N, N-dimethylacetamide, N, N-
Linear or cyclic amides or phosphorylamides such as dimethylformamide, N-methylpyrrolidone, γ-butyrolactone, hexamethylphosphoric triamide, or sulfoxides or sulfones such as dimethylsulfoxide, diphenylsulfone, tetramethylenesulfone, tetramethyl urea, N, N ^'- is a ureas such as dimethyl ethylene urea. These solvents need to be used in a substantially anhydrous state.
Other solvents inert to the reaction, such as benzene, toluene,
Xylene and the like can be mixed and used.

In the present invention, in order to produce an aliphatic or aromatic polyamideimide having excellent heat resistance and a controlled molecular arrangement capable of injection molding, the benzene-1,2,4-tricarboxylic acid is used. The anhydride and meta-xylylene diisocyanate are heated and reacted in an aprotic polar solvent at a temperature of 100 to 250 ° C in the presence of an alkali metal compound in a molar ratio of 0.475 to 0.525 to effect imidization. Amidation must be performed by adding benzene-1,2,4-tricarboxylic anhydride in a molar ratio of 0.475 to 0.525 and heating at a temperature of 150 ° C. or higher. The reactivity of benzene-1,2,4-tricarboxylic anhydride with the isocyanate of the anhydride ring and carboxyl group was investigated using phthalic anhydride and benzoic acid as model compounds. In the reaction of carboxyl groups (amidation), it was found that there was a large difference between the rates of imidization and amidation in the temperature range of 100 to 250 ° C. benzene-
The first stage imidization reaction for condensing 1,2,4-tricarboxylic anhydride and diisocyanate requires a temperature of 100 to 250 ° C, more preferably a temperature of 140 to 180 ° C.
If the temperature is lower than 100 ° C., the reactivity between the anhydride ring and the isocyanate decreases, which is not preferable. If the temperature exceeds 250 ° C., the rate of amidation is increased, and a polymer having a controlled molecular arrangement cannot be obtained. In the second stage of the amidation reaction, the reactivity of diisocyanate is low.
The above temperature is required, and a temperature range of 200 to 260 ° C is more preferable. The intermediate diimide dicarboxylic acid is
In this case, a polycondensation reaction (amidation) with a diisocyanate is performed without isolation, but there is no problem even if the generated diimide dicarboxylic acid is isolated and subjected to a polycondensation reaction (amidation).

The reaction time is usually 1 to 20 hours for both the imidation and amidation reactions. The point at which the by-produced carbon dioxide is substantially not recognized can be regarded as the completion point of the reaction. The amount of the alkali metal compound to be added should be 0.5 to 0.5 to benzene-1,2,4-tricarboxylic anhydride.
The range is preferably 20 mol%, and particularly preferably 1.0 to 10 mol%. Generally, the concentration of the raw material monomer (benzene-1,2,4-tricarboxylic anhydride + meta-xylylene diisocyanate) is preferably in the range of 50 to 400 g / l, more preferably 10 to 400 g / l.
It is preferably from 0 to 300 g / l. In the present invention, the average molecular weight (weight average molecular weight according to GPC polystyrene, standard) of the obtained aliphatic or aromatic polyamideimide resin whose molecular arrangement is controlled is preferably 10,000 or more, and particularly preferably 20,000. That is all.

[0015]

The present invention will be described in detail below with reference to examples.
The physical properties of the polymers obtained in Examples and Comparative Examples were measured by the following methods. Average molecular weight: The polymerization solution was diluted with N-methylpyrrolidone, and the molecular weight distribution curve was measured using GPC.
Weight average molecular weight was obtained by standard. Flow temperature: (Shimadzu Corporation) Apparent melt viscosity measured using a flow tester is 10
000Poise temperature.

Example 1 In a 500 ml separable flask equipped with a stirrer, thermometer, cooling condenser and dropping funnel, benzene-1,2,4
- tricarboxylic acid anhydride 20.41 g (.1062 mol), potassium fluoride 0.130 g (.00223 mol), N, N ^'- dimethyl ethylene urea 220ml were charged dissolved in a nitrogen atmosphere, the internal temperature up to 140 ° C. with stirring The temperature rose. 9.96 g of meta-xylylene diisocyanate (0.05290
Mol), add all at once to the flask, and add
For 5 hours. Further, 9.98 g (0.05301 mol) of meta-xylylene diisocyanate was measured into the dropping funnel and added to the flask at one time. Immediately add this solution to 22
When the temperature was raised to 0 ° C., it reacted violently at 150 ° C. and generation of carbon dioxide was recognized. When stirring was continued at 220 ° C. for 1 hour, the color of the solution changed from yellow to reddish brown and the viscosity increased. After heating and aging for another 1 hour, the mixture was cooled to room temperature, and the polymerization liquid was poured into water under high-speed stirring to obtain a polymer powder. The polymer powder was further washed three times with water, and finally washed with methanol, and dried under reduced pressure at 150 ° C. for 8 hours.
3 g of a polymer powder were obtained. The average molecular weight of the polymer was 48,000. The glass transition temperature measured by DSC is
It had excellent heat resistance of 187 ° C and 5% decomposition temperature in air of 404 ° C. Furthermore, it had a flow temperature of 277 ° C and had heat melting properties that allow injection molding.

Examples 2 to 5 Using the experimental apparatus shown in Example 1, benzene-1,2,4-tricarboxylic anhydride and meta-xylylene diisocyanate were similarly polymerized under the respective conditions to obtain Table 1 shows the physical property values of the obtained polymers.

Example 6 Benzene-1,2,4-tricarboxylic anhydride and meta-xylylene diisocyanate were reacted in the experimental apparatus shown in Example 1 under the same conditions, and the obtained reaction solution was cooled. , PH
Bis-[(4-carboxy) phthalimide] -α, α'-metaxylene was isolated by placing the resultant in an aqueous hydrochloric acid solution adjusted to 2. The melting point measured by DSC was 342.3 ° C. Next, meta-xylylene diisocyanate was added to this compound for polycondensation, and the physical properties of the obtained polymer are shown in Table 1.

[Table 1]

Reference Example In a four-necked flask equipped with a stirring period, a thermometer, and a cooling condenser, 0.0072 g (0.000124 mol) of potassium fluoride was placed.
3.0267 g (0.0248 mol) of benzoic acid and 84.794 g of N, N'-dimethylethylene urea were charged and dissolved in a nitrogen atmosphere. After maintaining the temperature constant, 2.2224 g (0.0118 mol) of meta-xylylene diisocyanate was charged all at once, and the disappearance of meta-xylylene diisocyanate at each time was determined by liquid chromatography. Constant k
Was determined at each temperature. In addition, the reaction rate constant at each temperature of imidation was similarly obtained using phthalic anhydride. Table 2 shows the obtained reaction rate constants at each temperature.

[Table 2]

Comparative Example 1 30.23 g (0.1573 mol) of benzene-1,2,4-tricarboxylic anhydride and potassium fluoride were added to the experimental apparatus shown in Example 1.
0.2054 g (0.00354 mol) and 300 ml of N, N'-dimethylethyleneurea were charged and dissolved in a nitrogen atmosphere. 29.95 g of metaxylylene diisocyanate (0.1600 g) was added to the dropping funnel.
Mol) was added to the flask at one time. The internal temperature was raised to 200 ° C while stirring this solution.
The reaction violently occurred at 0 ° C., and generation of carbon dioxide was recognized. 20
When stirring was continued at 0 ° C. for 1 hour, the color of the solution changed from yellow to reddish brown, and the viscosity increased. After heating and aging for another 1 hour, the mixture was cooled to room temperature and post-treated in the same manner as in Example 1. The average molecular weight of the polymer was 59,000. D
It had a heat resistance of 189 ° C. as measured by SC and a decomposition temperature of 5% in air of 396 ° C., but showed a difference in heat resistance as compared with the polymer obtained in Example 1.

Comparative Example 2 30.42 g (0.1583 mol) of benzene-1,2,4-tricarboxylic anhydride, 29.99 g (0.1602 mol) of m-xylylene diisocyanate, 0.212 mol of potassium fluoride were obtained using the experimental apparatus shown in Example 1. g (0.00366 mol) and reaction temperature of 130 ° C,
Polymerization and post-treatment were carried out in the same manner as in Example 1. The average molecular weight of the obtained polymer was 8,600, and the reaction temperature was low, so that the degree of polymerization did not increase, and a high molecular weight polymer could not be obtained.

Comparative Example 3 Using the experimental apparatus shown in Example 1, 30.45 g (0.1585 mol) of benzene-1,2,4-tricarboxylic anhydride, 30.05 g (0.1606 mol) of m-xylylene diisocyanate, and no catalyst were used. Except for the addition, polymerization and post-treatment were carried out in the same manner as in Example 1. The average molecular weight of the obtained polymer was 1200. Since the polymerization was carried out without adding a catalyst, the degree of polymerization did not increase, and a high molecular weight polymer could not be obtained.

Comparative Example 4 In the experimental apparatus shown in Example 1, benzene-1,2,4-tricarboxylic anhydride chloride 30.56 g (0.1451 mol), metaxylylenediamine 19.89 g (0.1460 mol), potassium fluoride 0.
Polymerization and post-treatment were carried out in the same manner as in Example 1, except for 177 g (0.00305 mol). The average molecular weight of the obtained polymer is 59
In the case of No. 00, a high molecular weight polymer could not be obtained.

【The invention's effect】

According to the present invention, an aliphatic or aromatic polyamideimide resin having excellent heat resistance and having a controlled molecular arrangement capable of injection molding can be obtained by an industrially practical method. This is a useful invention.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masui Ohkita 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Inside Mitsui Toatsu Chemicals Co., Ltd. (72) Inventor Akihiro Yamaguchi 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui (58) Fields investigated (Int. Cl. ⁶ , DB name) C08G 18/06-18/76 C08G 73/14 CA (STN) REGISTRY (STN)

Claims (4)

(57) [Claims] 1. A compound of the general formula (I) In producing a polyamide-imide resin having a repeating unit of the formula: 1 mol of benzene-1,2,4-tricarboxylic anhydride, the formula OCNCH ₂ —R ₁ —CH ₂ N
The diisocyanate 0.475 to 0.525 moles of CO in the presence of an alkali metal compound as a catalyst, and reacted at 100 to 250 DEG ° C. in aprotic polar solvents, further wherein OCNCH ₂ -R
_2- CH ₂ NCO diisocyanate 0.475 to 0.52
A method for producing a polyamide-imide resin, comprising adding 5 mol and performing polycondensation at 150 ° C. or more to control the molecular arrangement. 2. A compound represented by the formula (II): In producing a polyamide-imide resin having a repeating unit represented by the following formula, 1 mol of benzene-1,2,4-tricarboxylic anhydride is added to 0.475 of meta-xylylene diisocyanate.
0.50.525 mol as a catalyst in the presence of an alkali metal compound in an aprotic polar solvent at 100 to 250 ° C.,
Furthermore, meta-xylylene diisocyanate 0.475-0.
A method for producing a polyamide-imide resin, comprising adding 525 mol and performing polycondensation at 150 ° C. or more to control the molecular arrangement. 3. The method according to claim 1, wherein the alkali metal compound is an alkali metal polycarboxylate, an alkali metal carbonate, an alkali metal bicarbonate, an alkali metal hydroxide, or an alkali metal fluoride. A method for producing the polyamide-imide resin described above. 4. The polyamide-imide according to claim 1, wherein the aprotic polar solvent is a linear or cyclic amide, phosphorylamide, phosphorylamide, sulfone, sulfoxide or urea. Method of manufacturing resin.