JPH0649758B2 - Butadiyne polyamide - Google Patents

Description

The present invention relates to a butadiyne-based polyamide, and more specifically, due to crosslinking of diacetylene groups, it has high strength and high elastic modulus not only in the molecular chain direction but also in the vertical direction of the molecular chain. The present invention relates to a butadiyne-based polyamide, which is a useful raw material for a polymer material that expresses.

[Prior art]

In recent years, application of compounds having a diacetylene group to optical materials, conductive materials and the like has been attempted. (D. Bloer, AR Earl Chance, "Polydiacetylene" NATO ASI Series E, Applied Science 102) In addition, the inventors of the present invention synthesized various compounds having a diacetylene group and used these as raw materials. We have been developing high modulus polymer materials.

[Problems that the invention is trying to solve]

Recently, wholly aromatic polyamide (aramid), which has been attracting attention as a high-strength, high-modulus fiber, has a number of excellent physical properties, but its strength and elastic modulus in the direction perpendicular to the molecular chain represented by fibrillation, etc. Poor adhesion is a problem on a practical level.

Therefore, the present inventors have added to the main chain of wholly aromatic polyamide,
By introducing a diacetylene group with excellent cross-linking properties, it retains high strength and high elastic modulus in the molecular chain direction, and by cross-linking with a diacetylene group, it also exhibits excellent mechanical properties in the direction perpendicular to the molecular chain. I have found a possibility.

However, when the amount of the introduced diacetylene group is increased, it has become difficult to increase the degree of polymerization of the polyamide, the production cost is increased, and the weather resistance and the alkali resistance are deteriorated. Therefore, as a result of investigating a method capable of increasing the degree of polymerization of aramid having excellent crosslinkability without losing the original properties of the wholly aromatic polyamide, a diacetylene group was included in a part of the dicarboxylic acid component of the wholly aromatic polyamide. It has been found that the introduction of a dicarboxylic acid component having a can synthesize a highly polymerized aromatic polyamide having excellent cross-linking reactivity.

However, although a high degree of polymerization can be achieved by reducing the content of diacetylene groups, when the obtained polymer is subjected to a crosslinking reaction after molding, the crosslinking effect is excellent, but the effect of crosslinking, for example, chemical resistance. The degree of improvement in alkali resistance, dimensional stability due to moisture absorption, etc. is not sufficient.

Therefore, in order to sufficiently enhance the effect of crosslinking, it was found that the molar fraction x of the structural unit should be in the range of 0.5 or more. When x is 0.5 or more, there is a problem that the solubility of the monomer is low and it is difficult to increase the degree of polymerization, but when x is 0.5 or more,
As a result of earnest research to obtain a degree of polymerization capable of wet molding, Of ultrafine powder of We have obtained the prospect that a high degree of polymerization can be achieved even when the content of diacetylene groups increases due to innovations in the polymerization method, such as being dissolved in the melt and introduced into a polymerization kettle.

[Means for solving problems]

The present invention comprises the following structural unit (1) or structural units (1) and (2), where x is the range represented by (Formula a), where x is the mole fraction of the structural unit (1). , Butadiyne-based polyamide having an inherent viscosity of 3.0 or more 0.5 ≦ x ≦ 0.9 (formula a) (Here, Ar ¹ , Ar ² and Ar ³ are Represents an organic group selected from ) Is provided.

In the present invention, Ar ¹ , Ar ² and Ar ³ are Is an organic group selected from.

Among these Ar ¹ , Ar ² and Ar ³ , the topochemical property is preferable, Ortho body and meta body of, in terms of rigidity, It is a para body of.

As the method for synthesizing the polyamide of the present invention, synthesis of a general wholly aromatic polyamide can be applied. For example, butadiyne-based acid chloride. Or / and the second acid chloride ... The diamine H ₂ NAr ¹ NH ₂ and / or H ₂ NAr
³ NH ₂ can be synthesized by means of solution polycondensation or interfacial polycondensation. In the solution polycondensation, diamine is preliminarily NMP (N
-Methylpyrrolidone), HMPA (hexamethylphosphortriamide), etc. dissolved in an aprotic polar solvent, CaCl ₂ , LiCl, MgCl ₂ , NaCl, and other inorganic salts coexist as necessary, and only with vigorous stirring. Or, and are added at a constant ratio to carry out polymerization. In the interfacial polycondensation, diamine is dispersed or dissolved in an alkaline aqueous solution containing NaOH, KOH, Ca (OH) ₂ or the like, and this solution is mixed with an organic solvent immiscible with water containing or (for example, carbon tetrachloride, chloroform, benzene). , Toluene, etc.) and vigorously stirred to synthesize.

However, in view of improving the degree of polymerization, solution polycondensation is preferable. In solution polycondensation, it is important that the total number of moles of acid chloride be as close as possible to 1: 1 with the number of moles of diamine.

The polymerization temperature is preferably in the range of 0 ° C to 100 ° C, and the solubility of the polymer at high temperature decreases as the content of the diacetylene group increases, so 20 ° C or less is particularly preferable for improving the degree of polymerization. The solvent is preferably dehydrated and purified, and the amount used is preferably as small as possible in order to improve the polymerization degree. For example, the solvent is 5 ml to 50 ml, preferably 5 ml to 10 ml per 1 g of diamine. As for the reaction atmosphere, it is preferable that the reaction is carried out in an inert gas such as dry argon or dry nitrogen, taking care not to allow water to enter. The solvent used is NMP, D
Aprotic polar solvents such as MF (dimethylformamide), DMAc (dimethylacetamide) and HMPA are preferable, and a mixed system thereof may be used if necessary.
In order to improve the degree of polymerization, CaCl, LiCl, Ca (S
An inorganic salt such as CN) ₂ is preferably added, and the amount thereof is 0.1 to 10 molar equivalents, preferably 0.8 equivalent to 2 equivalents, relative to the diamine.

In the above synthesis example, As a synthesis example of By an oxidative coupling reaction (Kreiser reaction) Is synthesized and hydrolyzed with an acid or alkali according to a conventional method, And a reaction with a chlorinating agent such as thionyl chloride or phosphorus trichloride.

For the method of synthesizing the compound and converting the ester group into an acid chloride, see, for example, Journal of Polymer Science Polymer Chemistry Edition Vol.
The method disclosed on page 11 (1984) can be used.

The butadiyne-based polyamide of the present invention relates to a polyamide copolymer having a high crosslinking effect and a high degree of polymerization, and a high degree of polymerization, that is, ηinh reaches 3 or more, preferably 4 or more.

In order to achieve such a high degree of polymerization, the solution polymerization method is more preferable, but in this case, the acid chloride is used. Is a problem in that it is dissolved in the polymerization solvent.

Acid chloride Is generally soluble in the polymerization solvent and is not a problem, Has extremely low solubility in the polymerization solvent. Therefore, In order to dissolve the acid chloride in a high concentration in a polymerization solvent, the acid chloride should be pulverized to 50 μm or less, preferably 30 μm or less by using a grinder, or a powder larger than 50 μm should be removed using a sieve. The acid chloride thus obtained is preferably used for the reaction. Also, in this case, if copolymerization is performed, It may be finely pulverized together, and it is rather preferable. Also, The desired amount of melt It is also effective to melt the compound and solidify it as it is, or to charge it into the reaction system as it is as a melt.

But, Decomposes as soon as it melts, so Do not use melts of.

Also, once dissolved in a low boiling point solvent having a higher solubility than a polymerization solvent such as chloroform or carbon tetrachloride, the reaction system is charged,
A method of removing these low boiling point solvents by reducing the pressure while polymerizing is also excellent.

It is not preferable to increase the amount of the polymerization solvent in order to dissolve it in the polymerization solvent because impurities such as water tend to easily enter in order to increase the degree of polymerization, and it is important to melt it in a small amount of the polymerization solvent. As the method, the above-mentioned method can be mentioned.

In the polyamide used in the present invention, the molar ratio of the structural unit (1) is 0.5 ≦ x ≦ in order to improve the effect of crosslinking.
0.9, and more preferably 0.8 ≦ x ≦ 0.9.
In order to increase the degree of polymerization, 0.5 ≦ x ≦ 0.7 is preferable.

〔The invention's effect〕

The butadiyne-based polyamide of the present invention exhibits high strength and high elastic modulus in the molecular chain direction because the molecular chain is rigid, and further exhibits high mechanical properties in the direction perpendicular to the molecular chain due to the crosslinking reaction of diacetylene groups. You can. Therefore, the butadiyne-based polyamide of the present invention is extremely useful as a raw material for a cross-linking material, a conductive material, an optical functional material, a non-fibril fiber as well as a structural material.

〔Example〕

Hereinafter, the present invention will be described with reference to examples, but needless to say, the present invention is not limited to the following examples.

The logarithmic viscosity ηinh described in the present invention means that 0.5 g of the polymer is 10
What was dissolved in 0 ml of solvent was measured using an Ostwald viscosity tube or Ubbelohde viscosity tube in a constant temperature bath at 30-40 ° C. (Ηr represents relative viscosity). As a solvent for dissolving the polymer, sulfuric acid, methanesulfonic acid, chlorosulfuric acid or the like is used, and it is possible to mix other solvents or to mix two-component solvents. The type is not particularly limited, but it is necessary to sufficiently confirm that the polymer is not modified during the measurement.

[Example 1] A copolymer consisting of Is dissolved in 500 ml of acetone, and this solution is mixed with 0.1 mol of CuC.
It was added to 200 ml of a pyridine solution containing 1 and the reaction was carried out at 30 ° C. for 5 hours while vigorously introducing oxygen gas.

After the reaction, the reaction product was poured into a large amount of water, and the separated solid was isolated by suction filtration. After recrystallizing this solid from methylene chloride, 4N-NaOHaq and a mixed solvent of methanol were reacted under reflux for 10 hours. After the reaction, it was treated with hydrochloric acid and separated. Was isolated by filtration and dried thoroughly. After drying, it was reacted with thionyl chloride for 12 hours at 70 ° C. in the presence of a catalytic amount of DMF. After the reaction, suction filtration in nitrogen, recrystallization from anhydrous toluene twice, Was synthesized.

Of this monomer The overall yield from was 88%.

Precisely weigh 1.0 mol of purified P-phenylenediamine and dry Ca
Dissolve in anhydrous NMP1.2 with Cl ₂ 1.4mol, 0-5
Cooled to ° C. The atmosphere is nitrogen. In this solution, What melt | dissolved xmol in 85 degreeC melt | dissolution of terephthalic acid chloride 1-xmol, and cooled to room temperature was added all at once, and also it vigorously stirred for 60 minutes with a homogenizer. After the reaction, the polymer was poured into a large amount of water to isolate the polymer that had broken out.
The yield of the obtained polymer was almost quantitative. After isolation, it was dried in a vacuum dryer at 50 ° C. for 2 days. The obtained polymer was pale yellow, was substantially insoluble in amide solvents such as NMP and DMAc, and was soluble in methanesulfonic acid. Table 1 shows ηinh when x is variously changed.
showed that.

Methanesulfonic acid was used as the solvent for ηinh measurement, and measurement was performed at 35 ° C.

As a result of IR (nujol) measurement of the obtained polymer, absorption was observed at 3303, 1639, 1310, 850 cm ^-1 .

Dissolves in 100% H ₂ SO ₄ , but runs from experiment numbers 1 to 5
The above copolymers are substantially insoluble in 100% H ₂ SO ₄ when heat-treated at 360 ° C. for 10 minutes in nitrogen. Moreover, no decomposition was observed from the elemental analysis results of the heat-treated polymer. Also, in this embodiment, Was not dissolved in the melt of terephthaloyl chloride, and when it was crushed and added to the reaction system, most of it did not dissolve, and η
The inh did not exceed 1.0.

[Example 2] When A copolymer consisting of Using the Journal of Polymer Science
Using the method of Polymer Chemistry Edition Vol. 22, p. 3011 (1984) and the method of Example 1, Was synthesized.

1.0 mol of purified m-phenylenediamine was precisely weighed and dissolved in anhydrous NMP1.0 together with 1.4 mol of dry CaCl ₂ .
Cooled to 5-10 ° C. The atmosphere is nitrogen. In this solution, Was dissolved in a melt of isophthalic acid chloride 1-xmol at 50 ° C, cooled to 0 ° C, added all at once, and further stirred vigorously for 60 minutes using a homogenizer. For the reaction treatment, the same method as in Example 1 was used. The yield of polymer is
It was almost quantitative. The obtained polymer was pale yellow and was soluble in NMP and methanesulfonic acid. The following table shows ηinh when x is variously changed. Methanesulfonic acid was used as the solvent for ηinh measurement, and ηinh was measured at 35 ° C.

As a result of IR (nujol) measurement of the obtained polymer, absorption was observed at 3300, 1640, 1608, 1310, 761 cm ^-1 .

Is soluble in NMP containing 5% CaCl ₂ , but the copolymers of Experiment Nos. 1 to 4 are substantially soluble in NMP containing 5% CaCl ₂ when heat-treated in helium at 360 ° C for 15 minutes. I didn't.

Claims (1)

[Claims] 1. The following structural unit (1) or structural units (1) and (2)
And the molar fraction of the structural unit (1) is X, X is in the range represented by (Formula a), and the butadiyne-based polyamide has an inherent viscosity of 3.0 or more. 0.5 ≦ X ≦ 0.9 (Formula a) (Here, Ar ¹ , Ar ² and Ar ³ are Represents an organic group selected from )