JPH0331324A - Aromatic polyamide - Google Patents

Abstract

PURPOSE:To obtain the subject new melt moldable polyamide, expressed by specific recurring units, excellent in heat resistance and processability with low water absorptivity and useful as a substrate for space aircraft, equipment and materials for electrical and electronic parts, raw material for heat-resistant fiber, etc. CONSTITUTION:The objective polyamide expressed by formula I (the positions of the two carbonyl groups are the o-, m- or p-positions of the benzene nuclei; n is 1-1000). Furthermore, the aforementioned polyamide is produced by polymerizing 4, 4'-bis(3-aminophenoxy)biphenyl expressed by formula II with a benzenedicarboxylic acid, such as isophthalic acid, a benzenedicarbonyl chloride, such as terephthaloyl dichloride, and a benzenedicarboxylic acid derivative, such as dimethyl terephthalate, in a solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel aromatic polyamide that is highly heat resistant and melt moldable.

[Prior art]

Aromatic polyamides, which are conventionally obtained by reacting aromatic diamines or aromatic diisocyanates with aromatic dicarboxylic acids or their derivatives, will continue to have excellent heat resistance due to their various excellent physical properties and good heat resistance. It is expected that it will be widely used in fields where this is required.

However, the aromatic polyamides that have been developed so far are
Although many of them have excellent mechanical properties and heat resistance, they all have the drawbacks of poor moldability and high water absorption.

For example, aromatic polyamide (trademark: Kevlar, manufactured by DuPont), which has a basic skeleton represented by formula (II), has excellent properties such as flame retardancy, heat resistance, high tensile strength, and high modulus of elasticity.
No clear glass transition temperature, thermal decomposition temperature is 430℃
Since the processing temperature and the thermal decomposition temperature are close to each other, it is difficult to process when used as a molding material, and it is only used in the fields of fibers or pulp produced by wet spinning.

In addition, the water absorption rate is 4 for use as a base material for electrical/electronic parts.
It is as high as 65%, and it is clear that it has an adverse effect on dimensional stability, insulation, soldering heat resistance, etc.

[Problems to be solved by the present invention]

An object of the present invention is to obtain an aromatic polyamide that has excellent processability and low water absorption in addition to the excellent heat resistance that aromatic polyamide inherently has.

[Means for solving problems]

The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, have discovered a novel aromatic polyamide.

That is, the present invention is represented by the formula (I), in which the two carbonyl groups are at the ortho, meta or para position of the benzene nucleus, and n
is an aromatic polyamide, which is a positive number from 1 to 1,000.

The aromatic polyamide of the present invention has the formula (
Diamine represented by I[[), i.e. bis 4.4”-bis(3-
This is a novel aromatic polyamide obtained by polymerizing benzenedicarboxylic acid or a derivative thereof using aminophenoxy)biphenyl.

Benzenedicarboxylic acids used in this method include phthalic acid, isophthalic acid and terephthalic acid.

Further, as derivatives of benzenedicarboxylic acid, benzene dicarbonyl chloride such as phthaloyl dichloride, phthaloyl dichloride, isophthaloyl dichloride, isophthaloyl dichloride, terephthaloyl dichloride, terephthaloyl dichloride, acid anhydride such as phthalic anhydride, etc. or dimethyl phthalade, diethyl phthalade, dimethyl isophthalade, diethylisophthalade,
Examples include dialkyl benzenedicarboxylates such as dimethyl terephthalate and diethyl terephthalate.

These benzenedicarboxylic acids or their derivatives are
Each of them may be used alone or in combination of two or more.

That is, the aromatic polyamide of the present invention is characterized by using 4,4'-bis(3-aminophenoxy)biphenyl as a diamine component, and has excellent processability in addition to the heat resistance originally possessed by aromatic polyamide. It is a thermoplastic aromatic polyamide.

The aromatic polyamide of the present invention has excellent heat resistance and thermoplasticity, so it can be extruded and injection molded, and can be used as a base material for space/aircraft, materials for electrical/electronic parts, and more. It is an extremely useful aromatic polyamide that can be used for a variety of purposes, such as as a raw material for high-strength, highly heat-resistant fibers produced by melt-spinning.

The method for producing the aromatic polyamide of the present invention is not particularly limited, and conventionally known methods can be employed; for example, the aromatic polyamide can be obtained by the following method.

That is, 4.4'-bis(3-aminophenoxy)biphenyl and benzenedicarboxylic acid such as isophthalic acid, benzenedicarboxylic acid chloride such as terephthaloyl dichloride, benzenedicarboxylic acid derivative such as dimethyl terephthalate are polymerized in a solvent to form an aromatic compound. Obtain polyamide.

Solvents used in this method include, for example, N, N-
Dimethylformamide, N,N-dimethylacetamide, N,N-jetinylacetamide, N,N-dimethylmethoxyacetamide, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N
-Methylcaprolactam, dimethylsulfoxide, tetramethylurea, hexamethylphosphoramide, isoquinoline, 2,4-lutidine, pyridine, T-picoline, β
- Picoline, α-picoline, 2,6-lutidine, quinoline, triethylamine, tributylamine, tripentylamine, N,N-dimethylaniline, N,N-diethylaniline, dichloromethane, chloroform, carbon tetrachloride, methyl ethyl ketone, acetone, Cyclohexanone, acetophenone, tetrahydrofuran, benzene,
Examples include toluene, xylene, nitrobenzene, phenol, cresylic acid, 0-cresol, m-cresol, p-chlorophenol, O-chlorophenol, water, and the like.

Further, these solvents may be used alone or in combination of two or more, depending on the type of reaction raw material monomer and polymerization method.

When benzenedicarbonyl dichloride is used as a reaction raw material monomer, a dehydrochlorination agent is usually used in combination.

Dehydrochlorination agents used include triethylamine, tributylamine, tripentylamine, N.

N-dimethylaniline, N,N-diethylaniline, pyridine, α-picoline, β-picoline, T-picoline,
Examples include 2,4-lutidine, 2,6-lutidine, quinoline, isoquinoline, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, lithium carbonate, sodium hydrogen carbonate, calcium oxide, lithium oxide, ethylene oxide, propylene oxide, etc. It will be done.

Further, when benzenedicarboxylic acids are used as a reaction raw material monomer, a condensing agent is usually used.

Condensing agents used include sulfuric anhydride, thionyl chloride,
Sulfite ester, picryl chloride, phosphorus pentoxide, phosphite-pyridine condensing agent, triphenylphosphine-hexachloroethane condensing agent, propyl phosphoric anhydride-N-methyl-2-pyrrolidone condensing agent, etc. It will be done.

The reaction temperature is usually 150° C. or lower, preferably 30° C. or lower.The reaction pressure is not particularly limited, and the reaction can be carried out at normal pressure.

The reaction time varies depending on the type of reaction raw material monomer, the polymerization method, the type of solvent, the type of dehydrochlorination agent, the type of condensing agent, and the reaction temperature, but it usually takes a long time to produce the aromatic polyamide represented by the following formula (I). Allow reaction time to complete. Usually 10 minutes to 24 hours is sufficient.

Through such a reaction, an aromatic polyamide having a repeating unit of the following formula (I) can be obtained.

(In the formula, n represents a positive number from 1 to 1,000.) In other words, the above-mentioned An aromatic polyamide having the repeating unit (I) can be obtained.

The aromatic polyamide of the present invention is characterized by using 4,4'-bis(3-aminophenoxy)biphenyl and a benzenedicarboxylic acid derivative such as benzenedicarboxylic acid or benzenedicarboxylic acid dichloride as reaction raw material monomers. .

However, in order to improve the thermal stability and moldability of the aromatic polyamide, there is no problem in the present invention in capping the ends with a -valent amine, a -valent acid or an acid derivative.

That is, a part of the diamine component is an aromatic, aliphatic or alicyclic monoamine, and a part of the benzenedicarboxylic acid or benzenedicarboxylic acid derivative is an aromatic, aliphatic or alicyclic monocarboxylic acid or a monocarbonyl chloride. There is no problem in replacing it with a monocarboxylic acid derivative.

Monoamines that can be used as partial substitutes include, for example, aniline, toluidines, chloroanilines, aminophenols, naphthylamines, aminobiphenyls, aminophenylphenyl ethers, alkylamines,
Examples include cyclohexylamine. Examples of monocarboxylic acids include benzoic acid, naphthalene carboxylic acids, benzophenone carboxylic acids, diphenyl ether carboxylic acids, propionic acid, and cyclohexane carboxylic acid. Examples of monocarboxylic acid derivatives include benzoyl chloride, naphthalene carbonyl chloride, benzophenone carbonyl chloride, diphenyl ether carbonyl chloride, propionyl chloride, and cyclohexane carbonyl chloride.

When the aromatic polyamide of the present invention is supplied to melt molding,
The following fillers used in ordinary resin compositions are
It may be used to the extent that it does not impair the purpose of the invention. In other words, wear resistance improving materials such as graphite, carborundum, silica powder, molybdenum disulfide, and fluororesins, and reinforcing materials such as glass fiber, carbon fiber, boron fiber, silicon carbide fiber, carbon whisker, asbestos, metal fiber, and ceramic fiber. , antimony trioxide, magnesium carbonate,
Flame retardant improving materials such as calcium carbonate, electrical property improving materials such as clay and mica, tracking resistance improving materials such as asbestos, silica and graphite, acid resistance improving agents such as barium sulfate, silica and calcium metasilicate, iron. powder,
Thermal conductivity improvers such as zinc powder, aluminum powder, copper powder, etc.
Other materials include glass peas, glass bulbs, talc, diatomaceous earth, alumina, shirasu balloons, hydrated alumina, metal oxides, and colorants.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Note that the physical properties in Examples and Comparative Examples were measured by the following methods.

Logarithmic viscosity: Measured at 35°C after dissolving 0.50 g of polyamide powder in 100 d of hexamethylphosphoramide Glass transition temperature (Tg): DSC (Shimadzu DT-4
0 series, DSC-41M) 5% weight dehumidification temperature: Measured in air with DT^-TG (Shimadzu DT-40 series, DTG-40M) Melt viscosity: Shimadzu Koka flow tester CFT500A Measured with a load of 100 kg (Example 1) In a container equipped with a stirrer and a nitrogen introduction tube, 5.53 g (0,015 mol) of 4,4'-bis(3-aminophenoxy)biphenyl and N - After charging and dissolving 48.6 g of methyl-2-pyrrolidone, 3.036 g (0,030 mol) of triethylamine
was added and cooled to -15°C. After that, the stirring was strengthened and 3.045 g of terephthalic acid dichloride (0,0
15 mol) was charged in bulk, and stirring was continued at 0°C for 2 hours and then at room temperature for 1 hour. The viscous polymer solution thus obtained was filtered and discharged into vigorously stirred methanol to precipitate a white powder. This white powder was filtered, washed with methanol, and dried under reduced pressure at 180"C for 12 hours to obtain 7.10 g (yield: 95.1%) of polyamide powder. The logarithmic viscosity of this polyamide powder was 1.23a.
/g, the glass transition temperature was 237, 5°C and the 5% weight dehumidification temperature in air was 473"C.

The results of elemental analysis of the obtained polyamide powder are as follows.

HNO Calculated value (χ) 77.10 4.45 5.62 12
．． 84 actual value (χ') 76.9 4.5 5.5
13.1 The infrared absorption spectrum of the obtained polyamide powder is shown in FIG. 1. In this spectrum, remarkable absorption is observed near 1660 cm'', which is the characteristic absorption band of amide.

Furthermore, after dissolving the obtained polyamide powder in N-methyl-2-pyrrolidone, it was cast on a glass plate and heated to 150°C.
The polyamide film was heated for 1 hour at 250"C and for 2 hours at 250"C to obtain a colorless and transparent polyamide film.The tensile strength of this polyamide film was 1.020 kg/c+fl, and the tensile elongation was 25%. ASTM D-8
Based on 82.

Moreover, the water absorption rate of this film was 0.8%.

The measurement method is based on ASTM D-570-63.

(Example 2) The same procedure as in Example 1 was carried out except that terephthalic acid dichloride in Example 1 was changed to isophthalic acid dichloride, and 7.02 g of white polyamide powder with a logarithmic viscosity t of 30 d/g was prepared.
(yield 94%).

The glass transition temperature of this polyamide powder is 227.0″C2
The 5% dehumidification temperature in air was 47B and 6°C.

The results of elemental analysis of the obtained polyamide powder are as follows.

C) INO calculated value (χ)? ? , 10 4.45 5.62 12.
84 The infrared absorption spectrum of the obtained polyamide powder is shown in FIG. 2. In this spectrum, remarkable absorption is observed near 1660c+m-', which is the characteristic absorption band of amide.

A polyamide film was obtained in the same manner as in Example 1 using the obtained polyamide powder. The tensile strength of this polyamide film is 1. tsOkg/cj - tensile elongation rate is 2
7%, and the water absorption rate was 0.75%.

(Example 3) 3.045 g of terephthalic acid dichloride in Example 1
(0,015 mol) of terephthalic acid dichloride.
The procedure was repeated in the same manner as in Example 1 except that 523 g (0,0075 mol) and isophthalic acid dichloride were used, and the logarithmic viscosity was 1.23 d1/
7.1 g (yield 95.1%) of white polyamide powder was obtained.

The glass transition temperature of this polyamide powder was 234°C, and the temperature of 5% weight loss in air was 478°C.

A polyamide film was obtained in the same manner as in Example 1 using the obtained polyamide powder. The tensile strength of this polyamide film was 1.100 kg/c+11, and the tensile elongation was 27%.

(Example 4) 7.37 g (0,020 mol) of 4,4'-bis(3-aminophenoxy)biphenyl and N-methyl-2 were placed in a container equipped with a stirrer and a nitrogen inlet tube under a nitrogen atmosphere. - After charging and dissolving 65 g of pyrrolidone, 3.036 g (0,030 mol) of triethylamine was added and the mixture was cooled to -15°C. After that, strengthen the heat and add 3.800 g of terephthalic acid dichloride (0,018
7 mol) was charged in bulk and stirred at 0°C for 1.5 hours. Thereafter, 0.548 g (0.0039 mol) of benzoyl chloride was charged, and stirring was continued for 2 hours at O'C and then for 1 hour at room temperature. The resulting polymer solution was filtered and discharged into vigorously stirred methanol to precipitate a white powder, which was filtered out.

After washing this polyamide powder with methanol, 180
Dry under reduced pressure at °C for 12 hours to obtain 9.3 g (95% yield)
polyamide powder was obtained. The logarithmic viscosity of this polyamide powder was 0.55 a/g. The melt viscosity of the obtained polyamide was measured and found to be 5.800 voids at 360°C. The obtained strand was pale yellow and transparent, highly flexible and extremely strong.

In addition, this polyamide powder is 340'C5150kg/
The heat deformation temperature of the molded product obtained by compression molding using CD for 15 minutes was measured and found to be 225°C. The measurement method is AST
Based on MD-648, load 18.6kg/aA.

(Comparative Example 1) In a container equipped with a stirrer and a nitrogen introduction tube, 2.16 g (0.02
mol) and 56.2 g of N-methyl-2-pyrrolidone were charged and dissolved, and then 3.036 g of triethylamine (0
,030 mol) was added and cooled to -15°C.

After that, increase the stirring and add 3. terephthalic acid dichloride.
800 g (0,0187 mol) was charged in bulk and stirred at 0°C for 1.5 hours. Then, 0.548 g (0,0039 mol) of benzoyl chloride was charged and the temperature was 0°C.
Stirring was continued for 2 hours at room temperature, and then for 1 hour at room temperature.

The resulting polymer solution was filtered and drained into vigorously stirred methanol to yield a white powder. After filtering,
After washing this polyamide powder with methanol,
Dry under reduced pressure for 12 hours at
) polyamide powder was obtained. When the glass transition temperature of this polyamide powder was measured, it did not show a clear glass transition temperature. In addition, using a Koka type flow tester, 370
The melt viscosity was measured at °C and 400 °C, but there was no melt flow at either temperature.

〔Effect of the invention〕

The present invention provides a completely novel aromatic polyamide that has excellent processability and low water absorption, in addition to the excellent heat resistance inherent in aromatic polyamides.

[Brief explanation of drawings]

FIGS. 1 and 2 are examples of infrared absorption spectra of the polyamide powder of the present invention.

Claims (1)

[Claims] It is represented by the formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I), and the positions of the two carbonyl groups in the formula are either ortho, meta, or para positions of the benzene nucleus. Yes, n
is a positive number from 1 to 1,000.