JP3222227B2 - Polyamide resin and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel polyamide resin and a method for producing the same. More specifically, the present invention relates to an aliphatic or aromatic polyamide copolymer having excellent heat resistance and mechanical properties and capable of being melt-molded, and a method for producing the same.

[0002]

2. Description of the Related Art A wholly aromatic polyamide (aramid) is a crystalline polymer generally having a high melting point, and is widely used as a material suitable for fibers and the like because of its excellent heat resistance and strength. However, the melting point of these wholly aromatic polyamides is higher than the decomposition onset temperature, so that melt molding is practically impossible, and there are limitations on molding conditions, such as solution molding. As a method for solving these problems, attempts have been made to introduce an aliphatic chain into one of the monomer components to impart melt fluidity. For example, JP
JP-A-53536 discloses a molding polyamide comprising an aromatic dicarboxylic acid containing terephthalic acid as a main component and a linear aliphatic alkylenediamine.
No. 428 discloses a crystalline copolyamide from terephthalic acid, isophthalic acid and C6 diamine.
Japanese Unexamined Patent Publication No. 200402/2004 proposes a method for producing a polyamide mainly composed of an aliphatic dicarboxylic acid mainly composed of adipic acid and metaxylylenediamine. However, in the method of introducing a large amount of an aliphatic chain into one of the diamine component forming these polyamides or the monomer component of the carboxylic acid or the carboxylic acid derivative, the melt fluidity is imparted, but the thermal stability, heat resistance and the like are increased. There was a problem that it decreased.

As for the synthesis of polyamide using isocyanate and carboxylic acid, it has been difficult to obtain a high molecular weight polymer by ordinary methods.
By using a mono-alkali metal salt of a dicarboxylic acid as already proposed in JP-A-7-151615, a high molecular weight polymer can be obtained. However, the polymers synthesized here, such as adipic acid and aromatic diisocyanate, are also unsatisfactory in terms of heat resistance because they contain a large amount of aliphatic groups in the main chain. In any case, the polyamide resin has a drawback that it is hard and brittle in terms of mechanical properties.

On the other hand, polyamides containing no aliphatic chain in the main chain and having improved melt fluidity include monomers containing an ether bond as proposed in JP-A-62-177021. , Method of using
Attempts have been made to impart melt flowability by using special monomers, such as a method using an indane ring-containing monomer as proposed in JP-A-172732, but these monomers are expensive in any case. However, when used in large quantities, the cost was not satisfactory.

[0005]

SUMMARY OF THE INVENTION The present invention provides a polyamide resin which can solve at least a part of the above-mentioned disadvantages of the prior art, for example, a polyamide resin having excellent heat resistance and mechanical properties and capable of being melt-molded. It is another object of the present invention to provide a method for producing such a resin.

[0006]

As a result of the research, the present inventors have found that a polyamide resin which can solve the object of the present invention can be obtained by sealing the terminal of the polymer molecule with a specific terminal blocking group. They succeeded and completed the present invention. According to the present invention, such a polyamide resin has two kinds of aromatic dicarboxylic acids and an aromatic diisocyanate,
And using an aliphatic diisocyanate and a terminal blocking agent,
It can be obtained by reacting in an aprotic polar solvent in the presence of an alkali metal compound as a catalyst.

The first invention of the present invention provides the following formula (I)

Embedded image And a structural unit represented by the following formula (II)

Embedded image And a structural unit represented by the following formula (III)

Embedded image And the following formula (IV)

Embedded image Wherein the molar ratio of the total of the groups having the structural units of the formulas (I) and (II) to the total of the groups having the structural units of the formulas (III) and (IV) is 0.1. 10: 0.90
0.90: 0.10, the molar ratio of the total of the groups having the structural units of the formulas (I) and (III) to the total of the groups having the structural units of the formulas (II) and (IV) is 0.50 : 0.50 to 0.75:
An aromatic ring which is randomly arranged at 0.25 and has no substituent at the molecular terminal of the polymer, or
Isocyanate, a melt-moldable polyamide resin characterized by being sealed with an aromatic group substituted with a group having no reactivity with carboxylic acid,

According to a second aspect of the present invention, the following formula (I)

Embedded image And a structural unit represented by the following formula (II)

Embedded image And a structural unit represented by the following formula (III)

Embedded image And the following formula (IV)

Embedded image Wherein the molar ratio of the total of the groups having the structural units of the formulas (I) and (II) to the total of the groups having the structural units of the formulas (III) and (IV) is 0.1. 10: 0.90
0.90: 0.10, the molar ratio of the total of the groups having the structural units of the formulas (I) and (III) to the total of the groups having the structural units of the formulas (II) and (IV) is 0.50 : 0.50 to 0.75:
An aromatic ring which is randomly arranged at 0.25 and has no substituent at the molecular terminal of the polymer, or
In producing a melt-moldable polyamide resin characterized in that it is sealed with an aromatic group substituted with a group having no reactivity with isocyanate and carboxylic acid, the total amount of aromatic dicarboxylic acid is 1 mol. The aromatic dicarboxylic acid represented by the following formula (V): HOOC-Ar ₁ -COOH (V) (wherein, Ar ₁ represents a divalent monocyclic or condensed polycyclic aromatic group) 0.10
0.90 mole of the following formula _{(VI) HOOC-Ar 3 -COOH} (VI) (2 divalent non fused polycyclic aromatic wherein Ar ₃ is the aromatic radical connected each other with a direct bond or a bridge member 0.90 to 0.10 mol of an aromatic dicarboxylic acid represented by the following formula (VII): OCN-Ar ₂ -NCO (VII) (wherein Ar ₂ is a divalent aromatic group) 0.5 to 0.75 mol of an aromatic diisocyanate represented by the following formula (VII):
_{I) OCN-CH 2 -R 1} -CH 2 -NCO (VIII) ( wherein, 2 R _1, including a direct or 1 or more carbon atoms
Represents a valence group. 0.5 to 0.25 mol of the aliphatic diisocyanate represented by the formula (V) and 0.1 mol or less per 1 mol of the aromatic dicarboxylic acid of the formula (VI) And, at least one terminal blocking agent selected from the group consisting of isocyanates and aromatic monocarboxylic acids having a substituent that is not reactive with the carboxylic acid, in the presence of an alkali metal compound as a catalyst, aprotic polarity A method for producing a polyamide resin, wherein the reaction is carried out at 140 ° C. or higher in a solvent.

In the present invention, the substituent Ar ₁ is a divalent monocyclic or condensed polycyclic aromatic group. Examples of the aromatic group include a bifunctional aromatic group derived from benzene, naphthalene, anthracene, phenanthrene and the like. Ar ₁ may be a bifunctional monocyclic or fused polycyclic aromatic group of the formula:

Embedded image

The substituted Ar ₂ is a divalent aromatic group such as phenylene, substituted phenylene (eg, alkyl-substituted phenylene, alkoxy-substituted phenylene, halo-substituted phenylene), unsubstituted or substituted diphenylalkane, triphenyl Examples include divalent aromatic groups derived from alkanes, diphenyl sulfide, diphenyl sulfone, diphenyl ether, benzophenone, biphenyl, naphthalene, anthraquinone, anthracene, azobenzene, and the like. Ar ₂ may be a divalent group represented by the following formula.

Embedded image

Further, the substituent Ar ₃ is a divalent non-condensed polycyclic aromatic group in which aromatic groups are connected to each other directly or by a bridging member, such as diphenylalkane, diphenylsulfone, diphenylsulfoxide, diphenyl Examples include divalent aromatic groups derived from sulfide, diphenyl ether, benzophenone, biphenyl, and the like. Ar ₃ may be a divalent group represented by the following formula.

Embedded image

The substituent R ₁ is a direct bond or a divalent group containing one or more carbon atoms. Examples of the divalent group containing one or more carbon atoms include an alkylene group, an alkylene group containing an element other than carbon, and a divalent aromatic group such as phenylene, naphthylene, and divalent bicyclo (bicyclic Condensed ring) and the like. R ₁ may be a direct bond or a divalent group as shown in the following formula.

Embedded image

The aromatic dicarboxylic acids represented by the above general formula (V) include, for example, isophthalic acid, terephthalic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,5
-Dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, perylene-1,9-dicarboxylic acid, perylene-2,9-dicarboxylic acid and the like.

Examples of the aromatic dicarboxylic acid represented by the general formula (VI) include diphenyl-4,4'-dicarboxylic acid, diphenylsulfone-4,4'-dicarboxylic acid, and diphenylether-4,4'- Dicarboxylic acid, benzophenone-4,4'-dicarboxylic acid, 4,4'-doxycarbonyldiphenylmethane, 2- (4,4 '
-Dicarboxyphenyl) propane and the like.

The aromatic diisocyanate represented by the general formula (VII) includes, for example, phenylene-1,3-diisocyanate, phenylene-1,4-diisocyanate,
Tolylene-2,6-diisocyanate, tolylene-2,4-
Diisocyanate, 1-methoxybenzene-2,4-diisocyanate, 1-chlorophenylene diisocyanate, tetrachlorophenylene diisocyanate, meta-xylylene diisocyanate, para-xylylene diisocyanate, diphenylmethane-4,4'-diisocyanate,
Diphenyl sulfide-4,4'-diisocyanate, diphenyl sulfone-4,4'-diisocyanate, diphenyl ether-4,4'-diisocyanate, diphenyl ether-3,4'-diisocyanate, diphenyl ketone-4,4 '
-Diisocyanate, naphthalene-2,6-diisocyanate, naphthalene-1,4-diisocyanate, naphthalene-1,5-diisocyanate, 2,4'-biphenyl diisocyanate, 4,4'-biphenyl diisocyanate, 3,3 '
-Methoxy-4,4'-biphenyl diisocyanate, anthraquinone-2,6-diisocyanate, triphenylmethane-4,4'-diisocyanate, azobenzene-4,4'-
And diisocyanates.
-Diisocyanate, diphenylmethane-4,4'-diisocyanate and naphthalene-1,5-diisocyanate are preferred because they are industrially easily available and inexpensive.

Examples of the aliphatic diisocyanate represented by the general formula (VIII) include 1,2-diisocyanatoethane, 1,3-diisocyanatopropane, tetramethylene-1,4-diisocyanate, and pentane. Methylene-1,5-
Aliphatic diisocyanate derivatives such as diisocyanate, hexamethylene-1,6-diisocyanate, nonamethylene-1,9-diisocyanate, decamethylene-1,10-diisocyanate, ω, ω′-dipropyl ether diisocyanate, and meta-xylylene diisocyanate; Aromatic diisocyanate derivatives having a substituent on the side chain such as xylylene diisocyanate, and 2,4-diisocyanatomethyl [2,2,1] heptane, 2,5-diisocyanatomethyl [2,2, 1] Bicyclo (bicyclic condensed ring) compounds such as heptane are exemplified, and hexamethylene-1,6-diisocyanate and metaxylylene diisocyanate are particularly preferred because they are industrially easily available and inexpensive.

The molecular terminal blocking group of the polymer used in the present invention is an unsubstituted aromatic ring group or an aromatic ring group substituted with a group having no reactivity with isocyanate or carboxylic acid. The aromatic ring can be a monocyclic aromatic group, a condensed polycyclic aromatic group, or a polycyclic aromatic group in which aromatic groups are connected to each other directly or by a bridge member. For example,
Benzene, diphenylalkane, diphenylsulfone,
Unsubstituted aromatic ring groups derived from diphenyl sulfoxide, diphenyl sulfide, diphenyl ether, benzophenone, naphthalene and the like, and alkyl-, alkoxy-, and halogen-substituted aromatic ring groups thereof, for example, methyl-substituted, methoxy-substituted, and chloro-substituted aromatic Group. In particular, it is preferable to seal the molecular terminal of the polymer with an unsubstituted aromatic group derived from benzene, since heat resistance is improved.

As the molecular terminal blocking agent used in the present invention, a compound having an unsubstituted aromatic ring group or an aromatic ring group substituted with a group having no reactivity with isocyanate or carboxylic acid may be used. it can. The aromatic ring can be a monocyclic aromatic group, a condensed polycyclic aromatic group, or a polycyclic aromatic group in which aromatic groups are connected to each other directly or by a bridge member. As the molecular end capping agent, for example, benzoic acid, diphenylmethanecarboxylic acid, diphenylsulfoncarboxylic acid, diphenylsulfoxidecarboxylic acid,
Monocarboxylic acids such as diphenyl sulfide carboxylic acid, diphenyl ether carboxylic acid, benzophenone carboxylic acid, biphenyl carboxylic acid, naphthalene carboxylic acid, and anthracene carboxylic acid, and alkyl-, alkoxy-, and halogen-substituted monocarboxylic acids thereof. Preferably a monocarboxylic acid represented by the following formula,

Embedded image And derivatives in which the aromatic ring is substituted with a group having no reactivity with isocyanate or carboxylic acid. The above molecular terminal blocking agents may be used alone or in combination of two or more.

It will be apparent to those skilled in the art that in various aspects of the present invention, the reactants described in the present invention used to form the resin may have isomers. Thus, unless stated otherwise, references to reactants shall include all such isomers.

As the molecular terminal blocking agent, benzoic acid is particularly preferred because it is industrially easily available and inexpensive.
The thermal stability of polymers using these molecular endcapping agents is much better than those not using them.

The alkali metal compound used as a catalyst in the process of the present invention includes, for example, mono- and / or di- and / or tri- and / or tetralithium salts of dicarboxylic acids, tricarboxylic acids and tetracarboxylic acids, sodium salts, potassium salts. Alkali metal salts of polyvalent carboxylic acids such as salts, rubidium salts, cesium salts, and francium salts; alkali metal carbonates such as lithium carbonate, sodium carbonate, potassium carbonate, rubidium carbonate, cesium carbonate, and furanium carbonate; lithium hydrogen carbonate; Sodium hydrogen carbonate, potassium hydrogen carbonate, rubidium hydrogen carbonate,
Alkali metal bicarbonate such as cesium hydrogen carbonate, francium hydrogen carbonate, lithium hydroxide, sodium hydroxide,
Potassium hydroxide, rubidium hydroxide, cesium hydroxide,
Examples thereof include alkali metal hydroxides such as francium hydroxide, and alkali metal fluorides such as lithium fluoride, sodium fluoride, potassium fluoride, rubidium fluoride, cesium fluoride, and francium 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
-Dimethylformamide, N-methylpyrrolidone, γ-
Linear or cyclic amides or phosphorylamides such as butyrolactone and hexamethylphosphoric triamide, or sulfoxides or sulfones such as dimethylsulfoxide, diphenylsulfone and tetramethylenesulfone, tetramethylurea, N, N'-dimethylethyleneurea Ureas such as These solvents need to be used in a substantially anhydrous state.
Other solvents inert to the polymerization reaction, for example, benzene, toluene, xylene and the like can be mixed and used.

In the present invention, in order to produce a polyamide having excellent heat resistance and mechanical properties and capable of being melt-molded, an aromatic dicarboxylic acid represented by the general formula (V) and a general formula (V)
When the total amount of the aromatic dicarboxylic acid represented by the formula (I) is 1 mol, the aromatic dicarboxylic acid of the formula (V) is 0.10 to 0.1.
90 moles of the aromatic dicarboxylic acid of formula (VI) 0.90 to 0.90
0.10 mol, 0.5 to 0.75 mol of the aromatic diisocyanate represented by the general formula (VII), 0.5 to 0.25 mol of the aliphatic diisocyanate represented by the general formula (VIII), Further, it is necessary to carry out a heating reaction at a temperature of 140 ° C. or more in an aprotic polar solvent in the presence of an alkali metal compound in the presence of an additive of a molecular terminal blocking agent of 0.1 mol or less.

The molar ratio of the aromatic dicarboxylic acid represented by the general formula (V) to the aromatic dicarboxylic acid represented by the general formula (VI) used in the present invention is such that the total of each dicarboxylic acid is 1 mol. In this case, the range of 0.90 to 0.10 mol of the aromatic dicarboxylic acid of the formula (VI) is preferably based on 0.10 to 0.90 mol of the aromatic dicarboxylic acid of the formula (V). 0.30 to 0.70 of an aromatic dicarboxylic acid
0.70 to 0.70 mol of the aromatic dicarboxylic acid of the formula (VI)
A range of 0.30 mol is more preferred. When the molar ratio of the aromatic dicarboxylic acid of the formula (V) is less than 0.10, or when the molar ratio of the aromatic dicarboxylic acid of the formula (VI) exceeds 0.90, the obtained polymer has poor heat resistance. And the cost increases. If the molar ratio of the aromatic dicarboxylic acid of the formula (V) exceeds 0.90, or if the molar ratio of the aromatic dicarboxylic acid of the formula (VI) is less than 0.10, the mechanical properties will decrease.

The molar ratio of the aromatic diisocyanate represented by the general formula (VII) is preferably in the range of 0.5 to 0.75 mol, when the total amount of the aromatic dicarboxylic acid is 1 mol. A range of 0.55 to 0.65 mol is more preferred. When the molar ratio is less than 0.5, the heat resistance of the obtained polymer deteriorates, and when the molar ratio exceeds 0.75, the polymer melt fluidity deteriorates.

Further, the molar ratio of the aliphatic diisocyanate represented by the general formula (VIII) is preferably in the range of 0.5 to 0.25 mol when the total amount of the aromatic dicarboxylic acid is 1 mol, A range of .45 to 0.35 mol is more preferred. If the molar ratio is less than 0.25, the melt fluidity of the obtained polymer becomes poor, and if the molar ratio exceeds 0.5, a polymer having excellent heat resistance cannot be obtained.

The amount of the molecular terminal blocking agent is preferably 0.1 mol or less, more preferably 0.08 mol or less, when the total amount of the aromatic dicarboxylic acid is 1 mol. The amount of the molecular end-capping agent is 0.1 mol / mol of the aromatic dicarboxylic acid.
If it exceeds 1 mol, the molecular weight of the obtained polymer decreases,
Heat resistance decreases.

The polymerization of the polyamide resin of the present invention is carried out by dissolving the above-mentioned two kinds of aromatic dicarboxylic acids, a molecular end-capping agent and a polymerization catalyst in an aprotic polar solvent and adding aromatic diisocyanate and aliphatic diisocyanate. , By heating.

The polycondensation reaction usually requires a temperature of 140 ° C. or higher, and more preferably a temperature range of 180 to 260 ° C. If the temperature is lower than 140 ° C., the reactivity between the carboxylic acid and the isocyanate decreases, which is not preferable. The reaction time is usually 1-2.
0 hours. 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 is preferably in the range of 0.5 to 20 mol%, more preferably 1.0 to 10 mol%, based on the aromatic dicarboxylic acid.

Generally, the starting monomer (dicarboxylic acid +
The concentration of the diisocyanate) is selected in the range of 50 to 400 g / l, and this concentration is selected depending on the reactivity of the starting monomers, the solubility of the polymer in the polymerization solvent, and the like. When the polymerization is started at a high concentration, it is preferable to add the solvent continuously or discontinuously depending on the case so that the stirring does not hinder the polymerization during the polymerization. In the present invention, the average molecular weight (weight average molecular weight according to the polystyrene standard of GPC) of the obtained polyamide resin is preferably 10,000 or more, particularly preferably 20,000 or more.

[0031]

The present invention will be described below in detail 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: dilute the polymerization solution with N-methylpyrrolidone,
The molecular weight distribution curve was measured using GPC, and the average molecular weight was obtained using a polystyrene standard. Flow temperature: Temperature at which the apparent melt viscosity measured by using a flow tester (manufactured by Shimadzu Corporation) reaches 10,000 Poise. Example 1

In a 500 ml separable flask equipped with a stirrer, thermometer, cooling condenser and dropping funnel, 10.49 g (0.06314 mol) of isophthalic acid, diphenyl ether-
16.31 g (0.06316 mol) of 4,4'-dicarboxylic acid, 0.147 g (0.00253 mol) of potassium fluoride, 0.0285 g (0.00023 g) of benzoic acid
3 mol) and 200 ml of N, N'-dimethylethyleneurea were charged and dissolved in a nitrogen atmosphere, and the internal temperature was raised to 140 ° C. while stirring this solution. 13.20 g (0.07579 mol) of tolylene-2,4-diisocyanate and hesamethylene-1,6
8.50 g (0.05054 mol) of diisocyanate was weighed and added all at once to the flask, and when the internal temperature was raised to 220 ° C, the reaction was violent and generation of carbon dioxide was recognized. 220
When stirring is continued for 2 hours at ℃, the color of the solution changes to yellow,
The viscosity increased. After heating and aging for another hour,
After cooling to room temperature, the polymerization liquid was poured into water under high-speed stirring to obtain a polymer powder. This polymer powder is further heated with hot water
After washing twice, and finally washing with methanol, it was dried in an inert oven at 180 ° C. for 8 hours to obtain 38.9 g of a polymer powder.

The average molecular weight of this polymer was 96,000. The glass transition temperature measured by DSC was 211 ° C., and the decomposition temperature in air was 5% at 429 ° C., indicating excellent heat resistance.
Further, it had a flow starting temperature of 294 ° C. and had a heat melting property capable of injection molding. Furthermore, the obtained polymer powder is
After dissolving in N-methyl-2-pyrrolidone, it was cast on a glass plate and heated at 150 ° C. for 1 hour and at 250 ° C. for 2 hours to obtain a transparent polyamide film. The tensile strength of this polyamide film was 1150 kg / cm ² , and the tensile elongation was 18%. This measurement method is based on ASTM D-882.

Examples 2 to 5 Two kinds of aromatic dicarboxylic acids, aromatic diisocyanates and aliphatic diisocyanates were similarly polymerized and post-treated in the experimental apparatus shown in Example 1 under the respective conditions. The physical properties of the obtained polymers and the results of the tensile test of the cast film are shown in Table 1 below.

[0035]

[Table 1]

Comparative Example 1 Terephthalic acid 20.98 was placed in a 500 ml separable flask equipped with a stirrer, thermometer, cooling condenser and dropping funnel.
g (0.163 mol), 0.147 g (0.00253 mol) of potassium fluoride, and 200 ml of N, N'-dimethylethylene urea were charged and dissolved in a nitrogen atmosphere. Only 21.99 g (0.1263 mol) of tolylene-2,4-diisocyanate was lightened in the dropping funnel and added to the flask at one time. When this solution was stirred and the internal temperature was raised to 200 ° C., it violently reacted at 140 ° C., and generation of carbon dioxide was recognized. When stirring was continued at 200 ° C. for 1 hour, the color of the solution turned yellow 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. This powder was further washed with hot water three times, and finally washed with methanol, and then dried in an inert oven at 200 ° C. for 8 hours.
5 g of a polymer powder were obtained.

The average molecular weight of this polymer was 230,000, the glass transition temperature was as high as 250 ° C. or higher, and it had sufficient heat resistance as a heat-resistant resin. A cast film was prepared in the same manner as in Example 1 and subjected to a tensile test. As a result, the tensile strength was 960 kg / cm ² and the tensile elongation was 9%, and the mechanical properties were excellent. It did not have the melt flowability that could be injection molded.

Comparative Example 2 The same reaction and post-treatment as in Comparative Example 1 except that the diisocyanate of Comparative Example 1 was changed to 21.2 g (0.1263 mol) of hexamethylene-1.6-diisocyanate and the catalyst was changed to 0.23 g (0.0017 mol) of potassium carbonate. Was done. The average molecular weight of the obtained polymer was 96,000, and the glass transition temperature was as low as 110 ° C., and did not have sufficient heat resistance as a heat-resistant resin. Also,
Using the obtained polyamide powder, a polyamide film was obtained in the same manner as in Example 1. The tensile strength of this polyamide film was 450 kg / cm ² , the tensile elongation was 3%, and the mechanical properties were not excellent.

Comparative Example 3 21.35 g (0.1461 mol) of adipic acid, 27.48 g (0.1460 mol) of meta-xylylene diisocyanate and 0.1% of potassium fluoride
Polymerization and post-treatment were carried out in the same manner as in Comparative Example 1 except that 6 g (0.0027 mol) was used. The average molecular weight of the obtained polymer is 6.
The glass transition temperature was as low as 50,000 and as low as 60 ° C., and it did not have sufficient heat resistance as a heat-resistant resin. 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 380 kg / cm ² , the tensile elongation was 3%, and the mechanical properties were not excellent.

Comparative Example 4 21.02 g of isophthalic acid (0.
1265 mol), 0.148 g (0.00255 mol) of potassium fluoride, 0.0321 g (0.000263 mol) of benzoic acid, and 200 ml of N, N'-dimethylethyleneurea were charged and dissolved in a nitrogen atmosphere, and the solution was stirred. The internal temperature was raised to 140 ° C. 6.61 g (0.03795 mol) of tolylene-2,4-diisocyanate and 14.89 g of hexamethylene-1,6-diisocyanate in the dropping funnel
(0.08853 mol), add all at once to the flask,
When the internal temperature was raised to 220 ° C., a vigorous reaction occurred and generation of carbon dioxide was recognized. When the stirring was continued at 220 ° C. for 2 hours, the color of the solution changed to yellow, 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. This polymer powder was further washed with hot water three times, and finally washed with methanol, and then dried in an inert oven at 140 ° C. for 8 hours to obtain 29.8 g of a polymer powder. The average molecular weight of this polymer was 83,000. The glass transition temperature measured by DSC was 159 ° C and the decomposition temperature in air was 5% at 426 ° C. However, the strands obtained by the flow tester showed that many bubbles were decomposed, indicating heat resistance. It did not have sufficient properties as a conductive resin.

[0041]

Industrial Applicability The polyamide resin of the present invention has excellent heat resistance and mechanical properties, and has hot-melt properties that can be melt-molded. In addition, the method for producing a polyamide resin in the present invention is practical and economical, and a polyamide resin having excellent heat resistance and mechanical properties and having heat melting properties capable of being melt-molded can be obtained.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Akihiro Yamaguchi 1190 Kasama-cho, Sakae-ku, Yokohama City, Kanagawa Prefecture Inside Mitsui Toatsu Chemicals Co., Ltd. (56) References JP-A-62-209123 (JP, A) JP-A-2 -206618 (JP, A) JP-A-2-274729 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 18/00-18/87 C08G 69/00-69/50

Claims (13)

(57) [Claims] (1) The following formula (I): And a structural unit represented by the following formula (II): And a structural unit represented by the following formula (III): And a structural unit represented by the following formula (IV): And the total of the groups having the structural units of the formulas (I) and (II) and the formula (I
II) and a group having a structural unit of the formula (IV) having a total molar ratio of 0.10: 0.90 to 0.90: 0.10, and a group having a structural unit of the formula (I) and the formula (III) And the formula (II) and the formula (I
The total molar ratio of the groups having the structural unit of V) is 0.50:
0.50 to 0.75: 0.25, randomly arranged in each other, and the molecular end of the polymer substituted with an aromatic ring having no substituent or a group having no reactivity with isocyanate or carboxylic acid. A melt-moldable polyamide resin, which is sealed with an aromatic group. 2. Ar ₁ in the formulas (I) and (II) is represented by the following formula: The polyamide resin according to claim 1, which is a divalent group represented by the formula: 3. Ar ₂ in the formulas (I) and (III) is represented by the following formula: The polyamide resin according to claim 1, which is a divalent group represented by the formula: 4. R ₁ in the formulas (II) and (IV) is represented by the following formula: The polyamide resin according to claim 1, which is a direct bond or a divalent group represented by the formula: 5. Ar ₃ in the formulas (III) and (IV) is represented by the following formula: The polyamide resin according to claim 1, which is a divalent group represented by the formula: 6. The polymer molecule end capping group is one selected from the group consisting of an unsubstituted aromatic monocarboxylic acid or an aromatic monocarboxylic acid having a substituent that is not reactive with isocyanate or carboxylic acid. The polyamide resin according to claim 1, which is an aromatic group derived from 7. The polymer molecule end capping group is: The polyamide resin according to claim 1, which is an aromatic group derived from the compound having a substituent that is not reactive with isocyanate and carboxylic acid. 8. The polyamide resin according to claim 1, wherein the polymer molecule terminal capping group is a group derived from benzoic acid. 9. A compound represented by the following formula (I): And a structural unit represented by the following formula (II): And a structural unit represented by the following formula (III): And a structural unit represented by the following formula (IV): And the total of the groups having the structural units of the formulas (I) and (II) and the formula (I
II) and a group having a structural unit of the formula (IV) having a total molar ratio of 0.10: 0.90 to 0.90: 0.10, and a group having a structural unit of the formula (I) and the formula (III) And the formula (II) and the formula (I
The total molar ratio of the groups having the structural unit of V) is 0.50:
0.50 to 0.75: 0.25, randomly arranged in each other, and the molecular end of the polymer substituted with an aromatic ring having no substituent or a group having no reactivity with isocyanate or carboxylic acid. In producing a melt-moldable polyamide resin characterized by being sealed with an aromatic group, the following formula (V) HOOC-Ar ₁ when the total amount of aromatic dicarboxylic acid is 1 mol. —COOH (V) (wherein, Ar ₁ represents a divalent monocyclic or condensed polycyclic aromatic group).
0.90 mole of the following formula _{(VI) HOOC-Ar 3 -COOH} (VI) (2 divalent non fused polycyclic aromatic wherein Ar ₃ is the aromatic radical connected each other with a direct bond or a bridge member aromatic dicarboxylic acids from 0.90 to 0.10 mole represented by a group.), the following equation (VII) OCN-Ar ₂ -NCO
(VII) (wherein Ar ₂ represents a divalent aromatic group) 0.5 to 0.75 mol of an aromatic diisocyanate represented by the following formula (VII)
_{I) OCN-CH 2 -R 1} -CH 2 -NCO (VIII) ( wherein, 2 R _1, including a direct or 1 or more carbon atoms
Represents a valence group. 0.5 to 0.25 mol of the aliphatic diisocyanate represented by formula (I) and 0.1 mol or less per mole of the total of the aromatic dicarboxylic acids of the formulas (V) and (VI) Acid, and isocyanate, at least one terminal blocking agent selected from the group consisting of aromatic monocarboxylic acids having a substituent that is not reactive with carboxylic acid, in the presence of an alkali metal compound as a catalyst, aprotic A method for producing a polyamide resin, wherein the reaction is carried out at 140 ° C. or higher in a polar solvent. 10. The end capping agent is: 10. The method according to claim 9, wherein the compound is a member selected from the group consisting of a compound having a substituent that is not reactive with isocyanate and carboxylic acid. 11. The method according to claim 9, wherein the terminal blocking agent is benzoic acid. 12. The alkali metal compound is at least one selected from the group consisting of alkali metal polycarboxylates, alkali metal carbonates, alkali metal bicarbonates, alkali metal hydroxides and alkali metal fluorides. The method according to claim 9, wherein: 13. The aprotic polar solvent comprises an amide,
The method according to claim 9, wherein the method is at least one selected from the group consisting of phosphorylamides, sulfones, sulfoxides, and ureas.