JPH07116290B2 - Method for producing polyamide elastomer - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a polyamide elastomer.

[0002]

2. Description of the Related Art Polyamide elastomer having polyamide 6 as a hard segment and polyalkylene oxide as a soft segment is a material widely used as an industrial material. As a method for producing this polyamide elastomer, for example, a dicarboxylic acid and ε-caprolactam are first reacted to synthesize a polyamide oligomer having carboxyl groups at both ends, and this is dehydrated and condensed with polyalkylene glycol. 50-5095
No. 86, JP-A No. 54-47798, etc.) and ε
-Method for dehydration condensation of caprolactam, dicarboxylic acid and polyalkylene glycol at the same time (Industrial Chemistry Magazine)
Vol. 62, No. 8, page 33 (1959), JP-A-58-210925, JP-A-62-81419, JP-A-63-278930) and the like are known.

Further, in the production of the above polyamide elastomer, a dehydration condensation catalyst is usually used to accelerate the reaction and increase the molecular weight. Examples of such a catalyst include titanium tetraalkoxide (Japanese Patent Publication No. 56-454).
19), zirconium tetraalkoxide, or hafnium tetraalkoxide (Japanese Patent Publication No. 58-114).
59), tin compounds (Japanese Patent Publication No. 63-6520).
6), antimony oxide (Japanese Patent Publication No. 63-65207), pyrophosphoric acid, triphosphoric acid, polyphosphoric acid, metaphosphoric acid and their esters (JP-A-63-278930). However, with these conventionally known catalysts, when the resulting polyamide elastomer does not have a high molecular weight, when a high molecular weight polymer is obtained, coloring is intense, when the reaction time is long, or a large amount of the catalyst is used. In some cases, it is necessary to do so, and a satisfactory catalyst has not been found yet.

[0004]

SUMMARY OF THE INVENTION The present invention provides a method for producing a high molecular weight polyamide elastomer which has a short reaction time and can reduce the amount of catalyst, and is transparent and less colored.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems of the prior art, the inventors of the present invention have conducted extensive studies focusing on dehydration condensation catalysts used in the production of polyamide elastomers, and as a result, various The present invention has been completed by finding that the above problems can be completely solved when a zirconyl compound is selected and used among dehydration condensation catalysts.

That is, the present invention is (A) having 4 to 2 carbon atoms.
0 dicarboxylic acid, (B) number average molecular weight 200-200
In a method for producing a polyamide elastomer by dehydration-condensing polyalkylene glycol of No. 00 and (C) ε-caprolactam, a method for producing a polyamide elastomer, which comprises using a zirconyl compound as a catalyst.

First, the constituent components of the present invention will be described.

Examples of the (A) dicarboxylic acid having 4 to 20 carbon atoms include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid and decalindicarboxylic acid. Examples thereof include various known dicarboxylic acids such as acids, succinic acid, adipic acid, sebacic acid, dodecanedioic acid and other aliphatic dicarboxylic acids, each of which may be used alone or in combination of two or more.

As the polyalkylene glycol (B) of the present invention, various known ones can be used, for example, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, block copolymers of ethylene oxide and propylene oxide, ethylene oxide. And a random copolymer of propylene oxide,
Examples thereof include alkylene oxide adducts of bisphenols. Examples of alkylene oxide adducts of bisphenols include those described in JP-A-1-144417.

The number average molecular weight of these polyalkylene glycols is 200 to 20,000, preferably 400 to 40.
00. When it is less than 200, the obtained polyamide elastomer becomes liquid at room temperature and does not exhibit elasticity as a thermoplastic elastomer, and when it exceeds 20,000, it becomes too hard and the time required for producing the polyamide elastomer becomes long, which is not realistic.

The molar ratio of the above component (A): component (B) is usually in the range of 1: 0.95 to 1.05.
When the ratio of the component (B) is less than 0.95 or exceeds 1.05, the molecular weight does not increase.

The polyester having a polyalkylene oxide in the main chain, which comprises these components (A) and (B), is a soft segment introduced into the polyamide elastomer of the present invention. The proportion of such a soft segment in the polyamide elastomer is usually 20 to 80% by weight.
The amount is preferably about 25 to 75% by weight. Two
If it is less than 0% by weight, it does not exhibit rubber elasticity at room temperature and becomes hard.
If it exceeds 0% by weight, the melting point is lowered to cause blocking, or heat resistance and mechanical strength are extremely deteriorated.

Further, (C) ε-caprolactam is introduced into the polyamide elastomer of the present invention as polyamide 6 which is a hard segment, and the proportion thereof is usually 20.
It is about 80 to 80% by weight, preferably 25 to 75% by weight. If it is less than 20% by weight, heat resistance and mechanical strength are weak, and if it exceeds 80% by weight, flexibility is lowered, which is not preferable. Since a portion of ε-caprolactam remains unreacted, it is preferable to use more than the desired amount introduced into the polyamide elastomer.

In the present invention, it is essential to use a zirconyl compound as a catalyst for dehydration condensation of the above-mentioned components (A), (B) and (C). That is, the object of the present invention has been achieved for the first time by selecting a zirconyl compound from among various dehydration condensation catalysts, and the object of the present invention cannot be achieved with a dehydration condensation catalyst other than a zirconyl compound. . The zirconyl compound refers to, among zirconium compounds, a compound which behaves as a zirconyl ion (ZrO ²⁺ ) or a complex of zirconyl ion. Examples of the zirconyl compound include zirconyl carbonate, zirconyl ammonium carbonate, zirconyl acetate, zirconyl ammonium acetate, zirconyl nitrate (or its hydrate), zirconyl sulfate, sodium zirconyl sulfate, zirconyl sulfate (or its hydrate), zirconyl phosphate. Typical examples thereof include zirconyl stearate, zirconyl octylate, zirconyl hydroxide, hydrated zirconyl oxide, and zirconyl chloride (or its hydrate). Among these, zirconyl carbonate, zirconyl acetate and zirconyl stearate are preferable. The amount of these zirconyl compounds used is 100 in total of the above components (A), (B) and (C).
0.001 to 5 parts by weight, preferably 0.
It is preferable to use 002 to 1 part by weight. If it is less than 0.001 part by weight, the molecular weight of the elastomer does not increase, and if it exceeds 5 parts by weight, gelation occurs or coloring becomes severe, which is not preferable. The zirconyl compound sufficiently functions as the catalyst of the present invention even when it is used in an amount of 0.001 to less than 0.01 part by weight. Thus, when a small amount of catalyst is used, the adverse effect on the performance of the obtained elastomer is very small.

The method for producing the polyamide elastomer of the present invention is not particularly limited, and either the above-mentioned two-step reaction or simultaneous reaction may be used. When the two-step reaction is adopted, first, ε-caprolactam and dicarboxylic acid are charged, and usually about 150 to 300 ° C., preferably 200
After reacting at a reaction temperature of ~ 280 ° C for about 2 to 24 hours to synthesize a polyamide oligomer having carboxyl groups at both ends, the above-mentioned predetermined amount of polyalkylene glycol and a catalyst are added to dicarboxylic acid at the same temperature. To react further. When the simultaneous reaction is adopted, a predetermined amount of ε-caprolactam, dicarboxylic acid, polyalkylene glycol and catalyst are charged in a batch, and usually 150-35.
At a reaction temperature of about 0 ° C, preferably 200 to 300 ° C,
Usually, the reaction is performed for about 2 to 24 hours. In addition, in any of the methods, a part of ε-caprolactam remains in the reaction system unreacted, and thus is removed under reduced pressure in a heated state after completion of the reaction. Further, when the polymerization degree of the obtained polyamide elastomer is to be increased, unreacted ε-
After removing caprolactam, 150-350 under reduced pressure
It is also possible to carry out post-polymerization at ° C.

During the reaction, an additive such as an antioxidant can be added in order to enhance the thermal stability of the obtained elastomer. Also, such additives may be added after the elastomer is manufactured. Examples of such additives include N, N′-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamide),
Pentaerythrityl-tetrakis [3- (3,5-di-
t-butyl-4-hydroxybutyl) propionate], 1,6-hexanediol-bis [3- (3,5
-Di-t-butyl-4-hydroxybutyl) propionate], 3,5-di-t-butyl-4-hydroxy-benzylphosphonate-diethyl ester, 1,3,5
-Trimethyl-2,4,6-tris (3,5-di-t-
Butyl-4-hydroxybenzyl) benzene, tris (2,4-di-t-butylphenyl) phosphite, tetrakis (2,4-di-t-butylphenyl) -4,
Hindered phenols such as 4′-biphenylene phosphite, phosphorus compounds such as triphenyl phosphite and tris (nonylphenyl) phosphite, amines such as N, N′-diphenyl-p-phenylenediamine, dilaurylthio Examples thereof include sulfur compounds such as dipropionate, alkali metal compounds, alkaline earth metal compounds and iodine compounds.

[0017]

According to the production method of the present invention, it is possible to produce a high-molecular-weight polyamide elastomer which is short in reaction time, can reduce the amount of catalyst, and is transparent and has little coloring.

Example 1 ε-caprolactam 633.6 g (5.6 mol), adipic acid 58.4 g (0.4 mol), polyethylene glycol (number average molecular weight 1530) 612 g (0.4 m)
ol), 1.3 g of zirconyl carbonate and Irganox 1
098 (N, N'-hexamethylenebis (3,5-di-
6.4 g of t-butyl-4-hydroxy-hydrocinnamide) (manufactured by Ciba-Geigy) was placed in a 2-liter reaction vessel and kept at 250 ° C. for 4 hours in a nitrogen stream. Then, the pressure was gradually reduced to remove unreacted ε-caprolactam, and the reaction was further performed at 1 Torr. After 70 minutes, the rotational torque (rotation speed: 200 rpm) of the stirrer reached 10 Kg · cm, and a slightly yellow transparent resin was obtained. The results are shown in Table 1.
Shown in.

Example 2 ε-caprolactam 633.6 g (5.6 mol), adipic acid 21.9 g (0.15 mol), polyethylene glycol (number average molecular weight 4020) 603 g (0.1
5 mol), 1.3 g of zirconyl carbonate and 6.4 g of Irganox 1098 (manufactured by Ciba-Geigy) were placed in a 2-liter reaction vessel and kept at 250 ° C. for 8 hours in a nitrogen stream. Then, the pressure was gradually reduced to remove unreacted ε-caprolactam, and the reaction was further performed at 1 Torr. 40
After a minute, the rotation torque of the stirrer (rotation speed 200 rpm) is 1
It reached 0 Kg · cm, and a slightly yellow transparent resin was obtained. The results are shown in Table 1.

Example 3 ε-caprolactam 486.6 g (4.3 mol), adipic acid 219.2 g (1.5 mol), polyethylene glycol (number average molecular weight 398) 597 g (1.5 m)
ol), 0.065 g of zirconyl carbonate and 6.4 g of Irganox 1098 (manufactured by Ciba-Geigy) were placed in a 2-liter reaction vessel and kept at 250 ° C. for 2 hours in a nitrogen stream. Then, the pressure was gradually reduced to remove unreacted ε-caprolactam, and the reaction was further performed at 1 Torr. After 90 minutes, the rotation torque of the stirrer (rotation speed 200 rpm) was 10
Kg · cm was reached and a slightly yellow transparent resin was obtained. The results are shown in Table 1.

Example 4 ε-caprolactam 633.6 g (5.6 mol), adipic acid 58.4 g (0.4 mol), polyethylene glycol (number average molecular weight 1530) 459 g (0.3 m)
ol), tetramethylene glycol (number average molecular weight 14
88) 148.8 g (0.1 mol), 1.3 g of zirconyl carbonate and 6.4 g of Irganox 1098 (manufactured by Ciba Geigy) were placed in a 2-liter reaction vessel and kept at 250 ° C. for 4 hours in a nitrogen stream. Then, the pressure is gradually reduced to remove unreacted ε-caprolactam, and further 1 Tor
The reaction was carried out at r. After 45 minutes, the rotation torque (rotation speed 200 rpm) of the stirrer reached 10 Kg · cm, and a slightly yellow transparent resin was obtained. The results are shown in Table 1.

Example 5 ε-caprolactam 633.6 g (5.6 mol), adipic acid 58.4 g (0.4 mol), tetramethylene glycol (number average molecular weight 1488) 595.2 g
(0.4 mol), 1.3 g of zirconyl carbonate and 6.4 g of Irganox 1098 (manufactured by Ciba Geigy) were placed in a 2-liter reaction vessel and kept at 250 ° C. for 4 hours in a nitrogen stream. Then, the pressure was gradually reduced to remove unreacted ε-caprolactam, and the reaction was further performed at 1 Torr. After 40 minutes, the rotation torque of the stirrer (rotation speed 200 rp
m) reached 10 kg · cm, and a slightly yellow transparent resin was obtained. The results are shown in Table 1.

[0023]

[Table 1]

Examples 6 to 8 The reaction was carried out in the same manner as in Example 1 except that the catalyst shown in Table 2 was used instead of the zirconyl carbonate of Example 1, and the results shown in Table 2 were obtained.

[0025]

[Table 2]

Comparative Examples 1 to 3 Reactions were carried out in the same manner as in Example 1 except that the catalysts shown in Table 3 were used instead of the zirconyl carbonate of Example 1, and the results shown in Table 3 were obtained.

[0027]

[Table 3]

 ─────────────────────────────────────────────────── ─── Continued Front Page (56) References Japanese Patent Publication Sho 58-11459 (JP, B2)

Claims (2)

[Claims] 1. A dicarboxylic acid having 4 to 20 carbon atoms,
(B) A method for producing a polyamide elastomer by dehydration-condensing a polyalkylene glycol having a number average molecular weight of 200 to 20,000 and (C) ε-caprolactam, wherein a zirconyl compound is used as a catalyst. . 2. The zirconyl compound is used in an amount of 0.001 to 5 parts by weight per 100 parts by weight of the total weight of the components (A), (B) and (C). Production method.