JPH03185023A - Aromatic polyamide - Google Patents

Abstract

PURPOSE:To obtain a melt moldable aromatic polyamide, having a specific structural formula, excellent in heat resistance, processability and water absorptivity and suitable as base materials for space aircraft. CONSTITUTION:An aromatic polyamide, obtained by reacting a diamine {preferably 1,4-bis[4-(4-aminophenoxy)-alpha,alpha-dimethylbenzyl]benzene and/or 1,3-bis[4-(4- aminophenoxy)-alpha,alpha-dimethylbenzyl]benzene} with a benzenecarboxylic acid derivative (e.g. phthalic acid) preferably in a solvent such as N,N- dimethylformamide at <=30 deg.C for 10min to 24hr, having recurring units expressed by the formula (n is 1-100), capable of extrusion and injection molding and suitable as a raw material, etc., for high-strength and highly heat-resistant fiber.

Description

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

[Conventional technology]

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

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

For example, aromatic polyamide (
DuPont's product (trademark: Kevlar) has excellent properties such as flame retardancy, heat resistance, high tensile strength, and high elastic modulus. However, this aromatic polyamide does not have a clear glass transition temperature and has a thermal decomposition temperature of about 430°C, and since the processing temperature and the thermal decomposition temperature are close to each other, it is difficult to process it for use as a molding material. There was a drawback. Therefore, it is only used in the fields of fibers or pulp produced by wet spinning. In addition, the water absorption rate is 4. It is clear that it has a negative effect on dimensional stability, insulation properties, soldering heat resistance, etc. when used as a base material for electrical and electronic parts.

[Problems to be solved by the present invention]

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

[Means to solve the problem]

The present inventors have made extensive studies to achieve the above-mentioned problems,
As a result, a new aromatic polyamide having the desired performance was discovered, and the present invention was completed.

That is, the present invention provides the formula (I) (I) (wherein, the two carbonyl groups are substituted at the ortho position, meta position, or rose position of the benzene nucleus, and n is t-t, oo
o is an integer).

The aromatic polyamide of the present invention contains a diamine represented by the formula (I[[) ([), i.e., 1,4-bis[4-(
4-aminophenoxy)-α,α-dimethylbenzyl 1
It is obtained by polymerizing benzene and/or 1,3-bis[4-(4-aminophenoxy)-α,α-dimethylbenzyl-1 benzene with benzene dicarboxylic acid or a derivative thereof.

That is, the aromatic polyamide of the present invention contains l,4-bis[4-(4-aminophenoxy)-α,α-dimethylbenzyl)benzene and/or 1,3-bis[4-
(4-Aminophenoxy)-α,α-dimethylbenzyl 1 It is characterized by using benzene as the diamine component, and is a thermoplastic aromatic polyamide that has excellent processability in addition to the heat resistance originally possessed by aromatic polyamides. It is polyamide.

This aromatic polyamide has excellent heat resistance and is thermoplastic, so it can be extruded or injection molded, and can be used as a base material for space/aircraft, electric/electronic parts, or by melt spinning. It is an extremely useful aromatic polyamide that can be used for a variety of purposes, including as a raw material for high-strength, highly heat-resistant fibers.

The method for producing the aromatic polyamide of the present invention is not particularly limited, and any conventionally known method can be employed.

For example, it can be obtained by the following method.

The aromatic diamine used in this method is 1,4-bis[4-(4-aminophenoxy)-α,α-dimethylbenzylbenzene or 1,3-bis[4-(4-aminophenoxy)- α,α-dimethylbenzyl 1-benzene, which may be used alone or in combination.

In addition, examples of the benzenedicarboxylic acid used include phthalic acid, isophthalic acid, terephthalic acid, etc.
In addition, as derivatives of benzenedicarboxylic acid, benzene dicarbonyl dihalogenides such as phthaloyl dichloride, phthaloyl dichloride, isophthaloyl dichloride, isophthaloyl dichloride, terephthaloyl dichloride, and terephthaloyl dichloride; and dialkylbenzenedicarboxylates such as dimethyl phthalade, diethyl phthalade, dimethyl isophthalade, diethylisophthalade, dimethyl terephthalate, and diethyl terephthalate.

These benzenedicarboxylic acids or their derivatives are
Each can be used alone or in a mixture of two or more.

The above diamine component and benzenedicarboxylic acid or its derivative are polymerized in a solvent.

Examples of the solvent used are N,N-dimethylformamide, N,N-dimethylacetamide, and N.

N-diethylacetamide, N,N-dimethylmethoxyacetamide, N-methyl-2-pyrrolidone, 1.3-
Dimethyl-2-imidazolidinone, N-methylcaprolactam, dimethyl sulfoxide, tetramethylurea, hexamethylphosphoramide, isoquinoline, 2,4-lutidine, pyridine, γ-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, toluene, xylene, nitrobenzene, phenol, cresylic acid, 0-cresol, m-cresol, p-chlorophenol, 0
- Chlorphenol, water and the like.

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

When benzenedicarbonyl chlorides are used as monomers as reaction raw materials, a dehydrohalogenating agent is usually used in combination.

Dehydrohalogenation agents used include triethylamine, tributylamine, tripentylamine, N, N
-dimethylaniline, N,N-diethylaniline, pyridine, γ-picoline, β-picoline, α-picoline, 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. .

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

The condensing agents used include sulfuric anhydride, thionyl chloride, sulfite ester, vicryl chloride, phosphorus pentoxide, phosphite-pyridine condensing agent, triphenylphosphine-
Hexachloroethane condensing agent, propyl phosphoric anhydride
Examples include N-methyl-2-pyrrolidone condensing agents.

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 dehydrohalogenating agent, the type of condensing agent, and the reaction temperature, but usually, the reaction time of the aromatic polyamide represented by formula (I) Allow the reaction to occur for a sufficient period of time to complete production. Usually, IO minutes to 24 hours is sufficient.

Through such a reaction, the formula (1) () (wherein, the two carbonyl groups are substituted at the ortho, meta, or para positions of the benzene nucleus, and n is 1-1,00
An aromatic polyamide having a repeating structural unit represented by 0 (an integer of 0) is obtained.

The aromatic polyamide of the present invention can also be obtained by conventional polyamide synthesis methods such as low-temperature solution polycondensation, interfacial polycondensation, and direct polycondensation.

The aromatic polyamide of the present invention contains 1,4-bis[4-(4-aminophenoxy)] as a reaction raw material monomer.
-α, α-dimethylbenzyl 1-benzene and/or 1,3-bis[4-(4-aminophenoxy)-α.

It is characterized in that it uses α-dimethylbenzyl-1 benzene and benzenedicarboxylic acid or a benzenedicarboxylic acid derivative such as benzenedicarboxylic chloride.

However, in order to improve the thermal stability and moldability of the aromatic polyamide, the ends of the polymer molecules may be capped using a -valent amine, a monovalent acid, or an acid derivative.

To obtain such aromatic polyamides, part of the diamine component is an aromatic, aliphatic or cycloaliphatic monoamine, and part of the benzenedicarboxylic acid or benzenedicarboxylic acid derivative is an aromatic, aliphatic or cycloaliphatic monoamine. prepared by replacing the formula with a monocarboxylic acid or a monocarboxylic acid derivative such as monocarbonyl chloride.

Monoamines that can be used as partial substitutes include, for example,
Aniline, toluidines, chloroanilines, aminophenols, naphthylamines, aminobiphenyls,
Examples include aminophenyl phenyl ethers, alkyl amines, and cyclohexyl amines. Further, examples of monocarboxylic acids include benzoic acid, naphthalene carboxylic acids, benzophenone carboxylic acids, diphenyl ether carboxylic acids, propionic acid, cyclohexane carboxylic acid, and the like. Examples of monocarboxylic acid derivatives include benzoyl chloride, naphthalene carbonyl chloride, benzophenone carbonyl chloride, diphenyl ether carbonyl chloride, propionyl chloride, cyclohexane carbonyl chloride, and the like.

The aromatic polyamide of the present invention can be subjected to melt molding.

In this case, fillers and the like used in ordinary resin compositions may be used to the extent that the purpose of the invention is not impaired. That is, abrasion resistance improving materials such as graphite, carborundum, silica powder, molybdenum disulfide, fluororesin, glass fiber, carbon fiber, boron fiber, silicon carbide fiber,
Reinforcing materials such as carbon whiskers, asbestos, metal fibers, and ceramic fibers, flame retardant improving materials such as antimony trioxide, magnesium carbonate, and calcium carbonate, and clay mica.
Electrical property improving materials such as asbestos, silica, graphite and other anti-tracking improving materials, barium sulfate,
Acid resistance improvers such as silica and calcium metasilicate; thermal conductivity improvers such as iron powder, zinc powder, aluminum powder, and copper powder;
Other materials include glass peas, glass bulbs, talc, diatomaceous earth, alumina, shirasu balloons, hydrated alumina, metal oxides, and colorants.

〔Example〕

EXAMPLES Hereinafter, the present invention will be explained in detail with reference to Examples and Comparative Examples to explain production examples of the aromatic polyamide of the present invention and the physical properties and performance of the obtained aromatic polyamide.

In the examples, various physical properties were measured by the following methods.

Logarithmic viscosity: 0.50g of polyamide powder with N-methyl-2
After dissolving in -pyrrolidone 100-, it was measured at 35°C.

Glass transition temperature (Tg): Measured by DSC (Shimadzu DT-40 series, DSC-41M).

5% weight dehumidification temperature: DTA-TG (Shimadzu DT-
40 series, DTG-40M).

Melt viscosity: Measured with a load of 100 kg using Shimadzu Koka flow tester CFT500A.

Example 1 1.4-bis[4-(4-aminophenoxy)-α,
α-Dimethylbenzyl 1-benzene 26.43g (0,0
After charging and dissolving 296 g of N-methyl-2-pyrrolidone and 296 g of N-methyl-2-pyrrolidone, 10.12 g of triethylamine (0
, 10 mol) and cooled to 5°C. After that, the stirring was strengthened and 10.15 g of terephthalic acid chloride (0,050
mol) was charged in batches, and stirring was continued at room temperature for 3 hours. The viscous polymer liquid thus obtained was discharged into methanol under vigorous stirring to precipitate a white powder.

After filtering this white powder, it was washed with methanol and heated to 180°
After drying under reduced pressure for 12 hours at C, 32.81 g (yield 99.
6%) polyamide powder was obtained.

The logarithmic viscosity of this polyamide powder is 2.04 dl/g, the glass transition temperature is 238.0°C, and the 5% weight loss temperature is 48.
The temperature was 0°8°C.

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

CHN O Calculated value (%) 80.22 5.81 4.25 9
．． 71 Actual value (%) 80.0 5.9 4.2 9
．． 9 In addition, FIG. 1 shows an infrared absorption spectrum diagram of the obtained polyamide powder.

In this spectrum diagram, 16 is the characteristic absorption band of amide.
Remarkable absorption was observed near 60 cm-' and 1510 cm-'.

Furthermore, after dissolving the obtained polyamide powder in N-methyl-2-pyrrolidone, it was cast onto a glass plate and heated at 150°.
C. for 1 hour and 250.degree. C. for 2 hours to obtain a colorless and transparent polyamide film. The tensile strength of this polyamide film is 1320kg/cm! The tensile elongation rate was 31%. Both measurement methods are based on ASTM D-882.

Moreover, the water absorption rate of this film was 0.72%.

The measurement method is based on ASTM D-750-63.

Example 2 The same procedure as Example 1 was carried out except that terephthalic acid chloride in Example I was replaced with isophthalic acid chloride, and 31.89 g (yield 96.8%) of polyamide powder with a logarithmic viscosity of 1.32 dl/g was obtained. Ta.

The glass transition temperature of this polyamide powder is 230.6℃,
The 5% weight loss temperature was 482.3°C. The results of the elemental distribution of the obtained polyamide powder are as follows.

CIN O Calculated value (%) 80.22 5.81 4.25 9.7
1 Actual value (%) 80.1 6.0 4.1 9.8
Moreover, an infrared absorption spectrum diagram of the obtained polyamide powder is shown in FIG.

In this spectrum diagram, 16 is the characteristic absorption band of amide.
Remarkable absorption was observed around 60 cm-' and around 1500 cm-'.

Furthermore, using the obtained polyamide powder, a colorless and transparent polyamide film was obtained in the same manner as in Example 1. The tensile strength of this polyamide film is 1280 kg/cm
'', the tensile elongation rate was 40%, and the water absorption rate was 0.65%.

Example 3 Example 1 10.15 g of terephthalic acid chloride
(0,050 mol), terephthalic acid chloride 5.08
g (0,025 mol) and isophthalic acid chloride 5.08
The same procedure as in Example 1 was carried out except that the polyamide powder 3 with a logarithmic viscosity of 1.61 cf//g was used, except that the
1.98 g (yield 97.1%) was obtained.

The glass transition temperature of this polyamide powder is 233.2°C
1 The 5% weight loss temperature in air was 480.5°C.

A colorless and transparent 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 290 kg/cm'', the tensile elongation was 40%, and the water absorption was 0.75%.

Example 4 1,4-bis[4-(4-aminophenoxy)-α,α-dimethylbenzyl 1benzene in Example 1 was converted to 1°3-bis[4-(4-aminophenoxy)-α,α- The same procedure as in Example 1 was carried out except that dimethylbenzyl was replaced with benzene, and 32.71 g of polyamide powder having a logarithmic viscosity of 1.55 dl/g was obtained.

The glass transition temperature of this polyamide powder is 200.1°C
The 15% weight loss temperature was 480.0°C.

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

CIN O Calculated value (%) 80.22 5.81 4.25 9.7
1 Actual value (%) 80.2 5.9 4.2 9.7 Furthermore, the infrared absorption spectrum of the obtained polyamide powder is shown in FIG. In this spectrum diagram, remarkable absorption was observed near 1660 cm-' and 1510 cl', which are characteristic absorption bands of amide.

Furthermore, using the obtained polyamide powder, a colorless and transparent polyamide film was obtained in the same manner as in Example 1. The tensile strength of this polyamide film is 1270 kg/cm
”, the tensile elongation rate was 37%, and the water absorption rate was 0.77%.

Example 5 The same procedure as in Example 4 was carried out except that terephthalic acid chloride in Example 4 was replaced with isophthalic acid chloride, and 31.98 g of polyamide powder with a logarithmic viscosity of 1.04 dl/g (
A yield of 97.1%) was obtained.

The glass transition temperature of this polyamide powder is 198.2°C
The 15% weight loss temperature was 497.9°C.

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

CHN O Calculated value (%) 80.22 5.81 4.25 9.7
1 Actual value (%') 80.3 5.8 4.0 9.
9 In addition, FIG. 4 shows an infrared absorption spectrum diagram of the obtained polyamide powder. This spectrum diagram shows the characteristic absorption band of amide near 1660 cm-' and 1500 cm-'.
A remarkable absorption was observed near '.

Furthermore, using the obtained polyamide powder, a colorless and transparent polyamide film was obtained in the same manner as in Example 1. The tensile strength of this polyamide film is 1140kg/cm
', the tensile elongation rate was 45%, and the water absorption rate was 0.81%.

Example 6 10.15 g of terephthalic acid chloride in Example 4 (
0,050 mol), 5.08 g of terephthalic acid chloride
(0,025 mol) and isophthalic acid chloride 5.08 g
The same procedure as in Example 4 was carried out except that (0,025 mol) was used, and polyamide powder with a logarithmic viscosity of 1.23 dl/g.
08g (yield 97.4%) was obtained.

The glass transition temperature of this polyamide powder is 199.0°C
The 15% weight loss temperature was 485.3°C.

A colorless and transparent polyamide film was obtained in the same manner as in Example I using the obtained polyamide powder. This polyamide film had a tensile strength of 1180 kg/cm'', a tensile elongation rate of 38%, and a water absorption rate of 0.80%.

Example 7 1.4-bis[4-(4-aminophenoxy)-α,
α-dimethylbenzyl]benzene 10.57 g (0,0
20 moles) and 75.3 g of N-methyl-2-pyrrolidone were charged and dissolved, and then 4.05 g of triethylamine (0
,040 mol) was added and cooled to 5°C. After that, the stirring was strengthened and 3.78 g (0,019 g) of terephthalic acid chloride was added.
mol) was charged in batches, and stirring was continued at room temperature for 2 hours.

Then, 0.590 g (0,004 g) of benzoyl chloride
2 mol) and continued stirring at room temperature for 2 hours. The obtained polymer liquid was discharged into methanol under vigorous stirring to precipitate a white powder. This white powder was separated by filtration, washed with methanol, and dried under reduced pressure at 180°C for 12 hours to obtain 13.10 g (yield: 98.6%) of polyamide powder. The logarithmic viscosity of this polyamide powder is 0.51 dl/
It was g. The melt viscosity of the obtained polyamide solution was measured and found to be 8000 poise at 350°C. The obtained strand was pale yellow and transparent, highly flexible, and extremely strong.

In addition, this polyamide powder was heated at 340℃ and 150kg/c.
The heat distortion temperature of the molded product obtained by compression molding for 15 minutes was measured at 220°C.The measurement method was ASTM
Based on Toro 48, load 18.6 kg/cm2.

Comparative Example 1 2.16 g (0.02 mol) of p-phenylenediamine was placed in a container equipped with a stirrer and a nitrogen inlet tube under a nitrogen atmosphere.
After charging and dissolving 56.2 g of N-methyl-2-pyrrolidone, 4.05 g (0,040 mol) of triethylamine was added, and the mixture was cooled to -15°C. After that, the stirring was strengthened and 3.80 g (0,0187 g) of terephthalic acid dichloride
mol) was charged in bulk and stirred at 0°C for 1.5 hours. Then, 0.548 g (0,0039 g) of benzoyl chloride
mol) and continued stirring at 0°C for 2 hours and then at room temperature for 1 hour. The resulting polymer solution was filtered and discharged into methanol with vigorous stirring to precipitate a white powder. After filtering this white powder, it was washed with methanol,
Drying under reduced pressure at 180°C for 12 hours gave 4.4g (yield: 97%).
．． 7%) polyamide powder was obtained. When the glass transition temperature of this polyamide powder was measured, it did not show a clear value.

Furthermore, the melt viscosity was measured at 370°C and 400°C, but no melt flow occurred 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]

FIG. 1, FIG. 2, FIG. 3, and FIG. 4 are examples of infrared absorption spectra of the polyamide powder of the present invention.

Claims (1)

[Claims] 1) Formula (I) ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (I) (In the formula, the two carbonyl groups are substituted at the ortho, meta or para positions of the benzene nucleus. , n is 1 to 1,00
an integer of 0).