JPH07116293B2 - Method for producing transparent hydrophilic polyamide elastomer and polyamide elastomer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a hydrophilic polyamide elastomer having excellent transparency and a polyamide elastomer obtained by this method. More specifically, a hydrophilic and transparent polyamide elastomer, which is suitable for imparting excellent antistatic properties by kneading with various resins, especially acrylic resins, or for obtaining a molded article having excellent water vapor permeability, is efficiently prepared. The present invention relates to a method for producing and a polyamide elastomer obtained by this method.

[0002]

2. Description of the Related Art Conventionally, a polyether ester amide type polyamide elastomer in which polyether is a soft segment and polyamide is a hard segment and both are connected by an ester bond has been widely used as an industrial material. In particular, a hydrophilic elastomer using polyoxyethylene glycol as a soft segment is used as a modifier for imparting antistatic properties to general resins, and is also used as a film having excellent water vapor permeability. Is being considered.

When used as such a resin modifier for antistatic purposes, it is sometimes required to have hydrophilicity, transparency and low hardness. To reduce the hardness, it is necessary to reduce the content of the hard segment.
Such a low hard segment content elastomer is
Since the water swelling property is remarkably large, it is difficult to recover by cooling with water like a general resin when polymerized and then cooled and solidified. Therefore, in such a case, it has been difficult to economically manufacture it because it has to be cooled by a special method such as contacting with a large amount of inert gas or contacting with a cooling drum.

Further, an elastomer having a low hard segment content, which uses a polyoxyalkylene glycol having a number average molecular weight of 1000 or less in the soft segment, has a drawback that the polyamide molecular weight becomes too small and is hard to harden even when cooled. . On the other hand, as a method for producing such a polyether ester amide type polyamide elastomer, for example, a method of condensing polyoxyalkylene glycol and polyamide dicarboxylic acid is known (Japanese Patent Publication No. 56-45419).

However, since polyamide and polyoxyalkylene glycol, especially polycapramide or polyhexamethylene adipamide and polyoxytetramethylene glycol, have low compatibility, they are not phase-separated even when they are mixed, and therefore, they are not mixed together. The system containing is disadvantageous in that a homogeneous polymer cannot be obtained. In order to improve such drawbacks, a method has been proposed in which, for example, polyoxytetramethylene glycol, caprolactam and dicarboxylic acid are reacted while controlling the water content of the reaction system to homopolymerize them (Japanese Patent Laid-Open Publication No. Sho. 61-24773
No. 2, JP-A-62-70422).

However, in this method, when polyoxyethylene glycol is used instead of polyoxytetramethylene glycol, it is difficult to obtain a high molecular weight polymer. Therefore, a method of obtaining a high molecular weight elastomer by using polyphosphoric acid as a catalyst is also available. Although proposed (Japanese Patent Laid-Open No. 63-278930), this method has a drawback that the obtained polymer is easily hydrolyzed because polyphosphoric acid remains in the polymer.

On the other hand, as a method for producing a polyamide elastomer containing polyoxyethylene glycol as a soft segment, a polyamide elastomer containing polyoxyethylene glycol having a number average molecular weight of 250 to 1000 as a polyether component and hexamethylene adipamide as an amide component. Has been proposed (JP-A-58-210926).
Issue).

However, in this case, when polyoxyethylene glycol having a number average molecular weight of 400 is used, a transparent elastomer can be obtained, but when 1000 is used, a semitransparent elastomer is obtained, and when it is 1500, phase separation is achieved. It is unavoidable that it will become an opaque elastomer. As described above, polyoxyethylene glycol has a stronger affinity with polyamide and is more compatible with polyoxytetramethylene glycol than polyoxytetramethylene glycol, but is difficult to be compatible with polyamide when its number average molecular weight exceeds 1,000. have.

Various methods for producing a hydrophilic polyamide elastomer containing polyoxyethylene glycol as a soft segment have been proposed (Japanese Patent Laid-Open No. 60-112).
826, JP-A-60-49028, JP-A-60-49029, JP-A-60-53537, and JP-A-59-221327), and in these methods, the transparent elastomer is All were obtained when only polyoxyethylene glycol having a number average molecular weight of 600 to 1000 was used, and when a polyoxyethylene glycol having a higher molecular weight than that was used or a mixture with polyoxytetramethylene glycol was used. In some cases it is not known to obtain transparent elastomers.

Therefore, the soft segment consists of polyoxyethylene glycol having a number average molecular weight of 1000 or more and diols such as polyoxytetramethylene glycol, and the hard segment polyamide is particularly caprolactam and hexamethylenediamine-adipate. It is the actual situation that a hydrophilic and transparent polyamide elastomer composed of the above copolymer has not been obtained so far.

[0011]

Under these circumstances, the present invention uses inexpensive diols having a number average molecular weight of 1,000 or more, has hydrophilicity, low hardness, and is transparent. Thus, it is an object of the present invention to provide a polyamide elastomer that can be easily recovered by cooling with water.

[0012]

The inventors of the present invention have completed the present invention as a result of intensive studies to achieve the above-mentioned object. That is, the present invention provides (A) a polyamide-forming monomer containing at least 50% by weight of caprolactam, (B) a dicarboxylic acid having 6 to 20 carbon atoms, and (C) a polyoxyalkylene glycol and an α, ω dihydroxy hydrocarbon. And a diol having a polyoxyethylene glycol segment content of 30 to 99% by weight and a number average molecular weight of 1000 to 4000, which is composed of at least one diol selected from Under an inert gas stream or 100-75
At a temperature of 180-280 ° C. under reduced pressure of 0 Torr,
The reaction is carried out while removing the water generated in the reaction, and the pressure is reduced to 100 Torr or less to distill off most of the unreacted caprolactam, and then titanium alkoxide and / or zirconium alkoxide is added to the reaction system. 5,
A method for producing a transparent hydrophilic polyamide elastomer, which comprises further polymerizing at a temperature of 220 to 280 ° C. under a reduced pressure of 0 Torr or less, and a relative viscosity of 1.5 or more and a wall thickness of 1 mm obtained by this method. Haze number is 50
% And 50 to 80% by weight of the component (C), the hydrophilic and transparent polyamide elastomer is provided.

The present invention will be described in detail below. In the present invention, the polyamide-forming monomer used as the component (A) of the raw material needs to contain at least 50% by weight, preferably 70% by weight or more of caprolactam. This is one in which the capramid unit is preferably 50% by weight or more of the units derived from the polyamide moldable monomer of the polyamide segment in the obtained polyamide elastomer, and a part of the charged caprolactam is recovered as unreacted caprolactam. It is important that the amount of unreacted caprolactam is taken into consideration during the preparation.

Examples of polyamide moldable monomers other than caprolactam include lauryllactam and 11-
Aminoundecanoic acid, 12-aminododecanoic acid, 6-aminocaproic acid, hexamethylenediamine-adipate, hexamethylenediamine-sebacate, hexamethylenediamine-isophthalate, hexamethylenediamine-terephthalate and the like can be mentioned. These may be used alone or in combination of two or more.

By copolymerizing these polyamide-forming monomers with caprolactam, (1) a different structure is introduced into the polyamide segment to become amorphous, (2)
The melting point of the elastomer is lowered, the kneading temperature with the resin is widened, and advantages such as (3) molding at a lower temperature occur. Further, the caprolactam also has a function as a compatibilizer, and in order to keep the polymerization system in a homogeneous molten state, it is necessary that the content of all the polyamide-forming monomers is 50% by weight or more. In the polyamide segment of the polyamide elastomer, the content of the capramide unit is 5 among the units derived from the polyamide-forming monomer.
If it is less than 0% by weight, the transparency of the elastomer tends to be lowered, which is not preferable, though it depends on the polyamide-forming monomer combined with caprolactam.

In particular, when hexamethylenediamine-adipate is used as the polyamide-forming monomer to be combined with caprolactam, the transparency of the resulting elastomer is likely to decrease, so that the content of caprolactam in all the polyamide-forming monomers should be reduced. It is advantageous to use 70% by weight or more. Even with the same content, if the molecular weight of diols becomes large, the molecular weight of polyhexamethylene adipamide also tends to become large, and the transparency tends to decrease. In addition, in terms of another index, it is preferable to use hexamethylenediamine-adipate in an equimolar amount or less to the diol.

In the present invention, a dicarboxylic acid having 6 to 20 carbon atoms is used as the raw material (B). Examples of such substances include adipic acid, sebacic acid, decanedicarboxylic acid, terephthalic acid, isophthalic acid, cyclohexanedicarboxylic acid and the like. These may be used alone or in combination of two or more. Good. By using the dicarboxylic acid as the component (B) in substantially equimolar amounts with the diols as the component (C) shown below, a polyamide elastomer having a high molecular weight can be obtained.

As the polyoxyalkylene glycol of the diol as the component (C), polyoxyethylene glycol and polyoxypropylene glycol, polyoxytetramethylene glycol, polyoxyhexamethylene glycol and polyoxyethylene polyoxypropylene block can be used. A polymer or the like is used. As these polyoxyalkylene glycols, those obtained by copolymerizing other diols such as butanediol, propylene glycol, neopentyl glycol and hydroquinone as an ether component can also be used.

As the α, ω dihydroxy hydrocarbon, for example, polyolefin glycol obtained by polymerizing olefin or butadiene to hydroxyl group the terminal and hydrogenating its double bond, hydrogenated polybutadiene glycol, 1,3 -Propanediol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, 1,4-bis- (hydroxymethyl) cyclohexane, dibutylene glycol and the like can be used.

Among these diols, in particular, a combination of polyoxyethylene glycol and polyoxytetramethylene glycol or polyoxypropylene glycol, a polyoxyethylene polyoxypropylene block copolymer, and further polyoxyethylene polyoxypropylene. A combination of a block copolymer and polyoxyethylene glycol is preferable because a transparent elastomer can be obtained in a relatively wide range of constitution ratio.

Of the above-mentioned diols, polyoxyalkylene glycols other than polyoxyethylene glycol or α, ω dihydroxy hydrocarbons have the effect of appropriately reducing the hydrophilicity of the elastomer obtained, and the hydrophilicity depends on the amount. It can be adjusted, but the amount of the polyoxyethylene glycol segment in the diol in the present invention needs to be selected to be 99 to 30% by weight, and further to be 95 to 50% by weight. Is preferred. When the amount of the polyoxyethylene glycol segment exceeds 99% by weight, the effect of lowering the hydrophilicity is not sufficient, and if water is used when cooling from a high temperature state, it swells remarkably and stickiness occurs, which makes recovery difficult. ,
If the amount is less than 30% by weight, it becomes difficult to obtain a transparent elastomer.

The diols have a number average molecular weight of 1000 to 4000, more preferably 1000 to 3 as a whole.
It is necessary to be in the range of 000, and it is necessary to select the number average molecular weight of each diol so as to be within this range depending on the constitutional ratio of each diol. This number average molecular weight is 1
When it is less than 000, the number average molecular weight of the polyamide segment in the elastomer becomes small, the melting point of the obtained elastomer becomes low, and it becomes difficult to solidify. On the other hand, if the number average molecular weight exceeds 4000, it becomes difficult to form a transparent elastomer.

The elastomer of the present invention must have a soft segment, that is, the content of the component (C) in the range of 55 to 80% by weight, preferably 60 to 75% by weight. If this amount is less than 55% by weight, a transparent composition cannot be obtained when kneaded with a resin, particularly an acrylic resin,
It is not flexible due to the large proportion of hard segments. On the other hand, if it exceeds 80% by weight, an elastomer having sufficient strength cannot be obtained.

By selecting the components (A), (B) and (C) as described above, an elastomer which is soft and transparent and has an appropriate hydrophilicity can be obtained, and the elastomer has a swelling property in water. Since it is small, it is easy to collect even if it is cooled with water. In the present invention, the above-mentioned components (A), (B) and (C) are treated with an inert gas stream or under a reduced pressure of 100 to 750 Torr, preferably 300 to 700 Torr to generate water out of the system. 180-280 ° C., preferably 220-while removing
It is necessary to react at temperatures in the range of 270 ° C. If the water generated in the reaction is not removed, the water content in the reaction system increases, homopolymerization of the polyamide-forming monomer takes precedence, and phase separation occurs, making it impossible to obtain a transparent elastomer. If it is 750 torr or more, the produced water is not sufficiently removed and a transparent elastomer cannot be obtained. If it is 100 torr or less, caprolactam is distilled off, and an elastomer having a predetermined composition cannot be obtained.

Further, when the reaction is carried out under an inert gas flow, as the inert gas, for example, nitrogen, argon, helium or the like can be used, but nitrogen is preferable from the economical point of view. Depending on the composition, the structure of the reaction vessel, etc., the flow rate of the inert gas and the degree of pressure reduction may be appropriately selected so that the produced water is removed. Furthermore, when the reaction is carried out under reduced pressure, for example, a partial condenser may be attached to reflux the caprolactam so that water can be removed to the outside of the system.

By removing the water produced in the reaction in this way, the reaction of esterification and amidation can occur at the same time, and even if a polyamide is produced, the caprolactam present in the system is compatibilized and the polymer is formed. Since the reaction is carried out so as to be incorporated in the system, the reaction progresses while maintaining the system in a homogeneous and transparent state, and a transparent elastomer is obtained. Then, because some caprolactam remains unreacted, 10
The unreacted caprolactam is distilled out of the system by reducing the pressure to 0 torr or less. The optimum degree of reduced pressure is appropriately selected according to the reaction temperature. The polymer obtained by this reaction has a relatively low molecular weight and needs to have a higher molecular weight. Therefore, titanium alkoxide and / or zirconium alkoxide is added to the reaction system as a catalyst, and the amount is 50 Torr or less, preferably 2 torr. 220-28 under reduced pressure below torr
It is necessary to carry out post-polymerization at a temperature in the range of 0 ° C, preferably 240-270 ° C. The pressure at this time is 50
When the pressure is higher than the torr, the polymerization time becomes long, which is not economical.

Since the titanium alkoxide and zirconium alkoxide are easily hydrolyzed and deactivated in the presence of water, in the present invention, most of the esterification reaction is completed, that is, a relatively low molecular weight. These catalysts are added after the water remaining in the reaction system is removed to the outside of the reaction system when the caprolactam is distilled off when the polyamide elastomer is formed. By doing so, the reaction time can be shortened and coloring or the like can be prevented.

The method of adding the catalyst is not particularly limited, and the reaction system may be returned to normal pressure, then added, and the pressure reduced again. Further, in the case of adding under reduced pressure, it is preferable to use it after diluting it with a melt of caprolactam because the catalyst is not distilled out of the reaction system. Furthermore, when added in this way, it is advantageous that white foreign matter due to the catalyst does not occur in the polymer.

In the present invention, known esterification catalysts such as antimony compounds and tin compounds may be used in combination so long as the transparency of the elastomer is not impaired. In the present invention, the degree of polymerization of the polyamide elastomer can be arbitrarily changed as needed, but the concentration is 0.5
It is necessary to polymerize so that the relative viscosity of the weight / volume% meta-cresol solution at a temperature of 30 ° C. is 1.5 or more. When the relative viscosity is less than 1.5, the mechanical properties of the elastomer are not sufficient, and more preferably, the elastomer having the relative viscosity of 1.6 or more is suitable.

The polyamide elastomer of the present invention obtained as described above has hydrophilicity and a wall thickness of 1 m.
The haze number at m is 50% or less and is transparent. To the polyamide elastomer, various heat stabilizers such as a heat resistant antioxidant and an antioxidant may be added in order to improve heat stability. There is no particular restriction on the timing of this addition,
It may be added at any stage of the initial, middle and final stages of the polymerization, or may be added after the completion of the polymerization. As the heat stabilizer, for example, N, N'-hexamethylenebis (3,5-di-t-butyl-4-hydroxycinnamic acid amide), 4,
4'-bis (2,6-di-t-butylphenol),
2,2'-methylenebis (4-ethyl-6-t-butylphenol), pentaerythrityl-tetrakis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate] various hindered phenols,
Aromatic such as N, N'-bis (β-naphthyl) -p-phenylenediamine, N, N'-diphenyl-p-phenylenediamine, poly (2,2,4-trimethyl-1,2-dihydroquinoline) Amines and the like are used. Further, an ultraviolet absorber, a coloring agent and the like can be optionally contained.

[0031]

The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto. The physical properties of the elastomer were determined as follows. (1) Relative viscosity Measured in meta-cresol under the conditions of 30 ° C and 0.5% by weight / volume. (2) Tensile breaking strength An elastomer is sandwiched between Teflon sheets, a sheet with a thickness of 1 mm is formed by hot pressing, and a dumbbell-shaped test piece is punched out in accordance with JIS K6301. )) Was measured. (3) Haze Number 0.4 mm thick polycarbonate transparent film [manufactured by Teijin Kasei Co., Ltd., trade name: Panlite Sheet] is sandwiched with an elastomer to create a sheet with an elastomer wall thickness of 1 mm. Number of haze is A
Based on STM D1003-61, it measured by the haze meter. (4) Shore hardness An elastomer was sandwiched between Teflon sheets and a sheet having a thickness of 5 mm was formed by hot pressing. Asker rubber hardness tester (A type) [Kobunshi Keiki Co., Ltd.]
Manufactured].

[0032]

Example 1 A 10-liter SUS reactor equipped with a stirrer, a nitrogen inlet, a distillation tube, and a catalyst charging pot was provided with 2020 g of polyoxyethylene glycol having a number average molecular weight of 1980 and polyoxytetramethylene having a number average molecular weight of 1830. 860 g of glycol, 248 g of terephthalic acid,
1300 g of caprolactam and 8 g of pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] were charged, and 500
The reaction was carried out at 250 ° C. for 3 hours while reducing the pressure to Torr.

Then, the pressure was gradually reduced to 2 torr to distill off unreacted caprolactam, and then a solution of 8 g of tetrabutoxyzirconium in 50 g of caprolactam was added to the reaction system from the catalyst pot under reduced pressure, and the reaction system was heated at 260 ° C. and The reaction was carried out for 2.5 hours with Tall. Molten polymer is made into a strand from the bottom of the reactor, extracted into water and cooled,
It was cut with a pelletizer to obtain transparent polyamide elastomer chips.

This elastomer has a soft segment content of 72% by weight, of which 70% by weight of a polyoxyethylene glycol segment is contained, and a haze number of 8%,
Relative viscosity 2 . 2, the tensile breaking strength was 230 kg / cm ² , and the shore hardness was 74A.

Example 2 A 500 ml glass reactor equipped with a stirrer, a nitrogen inlet, and a distillation tube had a number average molecular weight of 149.
0 polyoxyethylene glycol 64.0 g, number average molecular weight 1830 polyoxytetramethylene glycol 64.0 g, sebacic acid 15.8 g, caprolactam 7
7.5 g, hexamethylenediamine-adipate 2.
0 g and pentaerythrityl-tetrakis [3- (3,3
5-di-t-butyl-4-hydroxyphenyl) propionate] 0.4 g was charged, and nitrogen was supplied at 90 ml / min.
The mixture was allowed to react at 260 ° C. for 4 hours while flowing in. Then 5
The unreacted caprolactam was distilled off by gradually reducing the pressure to room temperature, the pressure was returned to normal pressure, and 0.4 g of tetrabutoxyzirconium was added to the mixture.
Reacted for hours. The molten polymer was made into a strand form from the reactor, extracted into water, cooled, and cut with a pelletizer to obtain transparent polyamide elastomer chips.

This elastomer has a soft segment content of 63% by weight, of which polyoxyethylene glycol segment is 50% by weight, and the haze number is 9%.
The relative viscosity was 2.1, the tensile strength at break was 260 kg / cm ² , and the shore hardness was 84A.

[0036]

Example 3 In a reactor similar to that of Production Example 1, 1920 g of polyoxyethylene glycol having a number average molecular weight of 1490,
480 g of polyoxytetramethylene glycol having a number average molecular weight of 1830, 239 g of adipic acid, 1750 g of caprolactam, hexamethylenediamine-adipate 1
17 g and pentaerythrityl-tetrakis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate] 8 g was charged, and nitrogen was 1 liter / m 2.
The mixture was reacted at 250 ° C. for 3 hours while flowing in. After that,
A polyamide elastomer chip was obtained in the same manner as in Example 1 except that the polymerization time after addition of the catalyst was 2 hours.

This elastomer had a soft segment content of 59% by weight, of which polyoxyethylene glycol segment was 80% by weight and had a haze number of 11
%, Relative viscosity 2.1, tensile breaking strength 330 kg / c
The m ² and the Shore hardness were 89A.

[0038]

Example 4 126 g of polyoxyethylene glycol having a number average molecular weight of 1490, 14 g of polyoxypropylene glycol having a number average molecular weight of 2000, and 18.5 of sebacic acid.
g, caprolactam 57 g, hexamethylenediamine-
Reaction was conducted in the same manner as in Example 2 except that 2.3 g of adipate and 0.4 g of pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] were charged. Then, unreacted caprolactam was distilled off, a catalyst was added, and polymerization was carried out at 260 ° C. and 1 Torr for 2 hours. Then, a polyamide elastomer chip was obtained in the same manner as in Example 2.

This elastomer had a soft segment content of 70% by weight, contained 90% by weight of a polyoxyethylene glycol segment, and had a haze number of 18
%, Relative viscosity 2.2, tensile breaking strength 230 kg / c
The m ² and the Shore hardness were 81A.

[0040]

Example 5 104 g of polyoxyethylene glycol having a number average molecular weight of 1490, 26 g of polyoxypropylene glycol having a number average molecular weight of 1030, and sebacic acid 19.2.
g, caprolactam 70 g, hexamethylenediamine-
1.8 g of adipate and N, N'-hexamethylene-
A polyamide elastomer chip was obtained in the same manner as in Example 4 except that 0.4 g of bis- (3,5-di-t-butyl-4-hydroxycinnamic acid amide) was charged.

This elastomer had a soft segment content of 65% by weight, of which polyoxyethylene glycol segment was 80% by weight and had a haze number of 20.
%, Relative viscosity 2.0, tensile breaking strength 260 kg / c
The m ² and the Shore hardness were 84A.

[0042]

Example 6 Polyoxyethylene polyoxypropylene glycol block copolymer having a number average molecular weight of 3330 [Nippon Yushi Co., Ltd., trade name: Pronone 204] 134
g, 8.2 g of sebacic acid, 85 g of caprolactam, and pentaerythrityl-tetrakis [3- (3,5-di-
Polyamide elastomer chips were obtained in the same manner as in Example 4 except that 0.4 g of t-butyl-4-hydroxyphenyl) propionate] was charged.

This elastomer had a soft segment content of 67% by weight, of which polyoxyethylene glycol segment was 40% by weight and had a haze of 15
%, Relative viscosity 2.1, tensile breaking strength 250 kg / c
The m ² and the Shore hardness were 82A.

[0044]

[Example 7] 117 g of polyoxyethylene glycol having a number average molecular weight of 1490, 13 g of polyolefin glycol having a number average molecular weight of 2200 (manufactured by Mitsubishi Kasei Co., Ltd., trade name: POLYTERH H), 17.1 g of sebacic acid, 78 g of caprolactam, and penta Erythrichyl tetrakis [3
A polyamide elastomer chip was obtained in the same manner as in Example 4 except that 0.4 g of-(3,5-di-t-butyl-4-hydroxyphenyl) propionate] was charged.

This elastomer had a soft segment content of 65% by weight, of which polyoxyethylene glycol segment was 90% by weight, and had a haze of 35.
%, Relative viscosity 2.0, tensile breaking strength 240 kg / c
The m ² and the Shore hardness were 83A.

[0046]

Example 8 101 g of polyoxyethylene glycol having a number average molecular weight of 1980, 25 g of polyoxytetramethylene glycol having a number average molecular weight of 1100, and adipic acid 1
0.8 g, caprolactam 87 g, hexamethylene diamine-sebacate 2.2 g and pentaerythrityl-
Charge 0.4 g of tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate],
After reacting and distilling off unreacted caprolactam in the same manner as in Example 2, 0.4 g of tetrabutoxytitanium was added, and polymerization was carried out at 260 ° C. and 1 Torr for 3 hours. Then
A chip of polyamide elastomer was obtained in the same manner as in Example 2.

This elastomer had a soft segment content of 63% by weight, of which polyoxyethylene glycol segment was 80% by weight and had a haze number of 8%,
The relative viscosity was 2.0, the tensile strength at break was 260 kg / cm ² , and the Shore hardness was 86A.

[0048]

Example 9 67 g of polyoxytetramethylene glycol having a number average molecular weight of 1000, 45 g of polyoxyethylene polyoxypropylene glycol copolymer having a number average molecular weight of 3330, 11.8 g of adipic acid, and caprolactam 1
06 g, hexamethylenediamine-sebacate 2.0
g and pentaerythrityl-tetrakis [3- (3,5
[Di-t-butyl-4-hydroxyphenyl) propionate] 0.4 g was prepared in the same manner as in Example 8 except that 0.4 g of the charged material was charged.

This elastomer has a soft segment content of 56% by weight, of which polyoxyethylene glycol segment is 76% by weight, and the haze number is 14%.
The relative viscosity was 2.0, the tensile strength at break was 330 kg / cm ² , and the shore hardness was 90 A.

[0050]

Example 10 116 g of polyoxyethylene glycol having a number average molecular weight of 1490, 6 g of polyoxytetramethylene glycol having a number average molecular weight of 2000, and 1 adipic acid
1.9 g, caprolactam 86 g, laurinlactam 6.5 g and pentaerythrityl-tetrakis [3-
(3,5-di-t-butyl-4-hydroxyphenyl)
Propionate] 0.4 g was charged and the nitrogen flow rate was 50 ml.
A chip of a polyamide elastomer was obtained in the same manner as in Example 8 except that / min was set.

This elastomer has a soft segment content of 61% by weight, of which polyoxyethylene glycol segment is 95% by weight, a haze number of 6%,
The relative viscosity was 2.0, the tensile breaking strength was 310 kg / cm ² , and the shore hardness was 87A.

[0052]

Example 11 A reactor similar to that of Example 1 was charged with polyoxyethylene glycol 1680 having a number average molecular weight of 1000.
g, polyoxytetramethylene glycol having a number average molecular weight of 1830, 720 g, 1,10-decanedicarboxylic acid 4
78 g, caprolactam 1550 g, hexamethylenediamine-adipate 54 g and 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4)
-Hydroxybenzyl) benzene (8 g) was charged and reacted at 250 ° C for 3 hours while flowing nitrogen at 1 liter / min. Next, the pressure was gradually reduced to 20 torr to distill off unreacted caprolactam, and then, under reduced pressure, 8 g of tetrabutoxytitanium was added to 50 g of caprolactam from the catalyst pot.
Was added to the reaction system and reacted at 250 ° C. and 1 torr for 3 hours. Thereafter, a polyamide elastomer chip was obtained in the same manner as in Example 1.

This elastomer has a soft segment content of 60%, of which 70% polyoxyethylene glycol segments are contained, a haze number of 7%, a relative viscosity of 2.0, a tensile breaking strength of 340 kg / cm ² , and a Shore hardness of 89A. Met.

[0054]

Example 12 The same reactor as in Example 1 was charged with polyoxyethylene glycol 2050 having a number average molecular weight of 1490.
g, polyoxytetramethylene glycol having a number average molecular weight of 1830, 510 g, sebacic acid, 335 g, caprolactam, 1520 g, hexamethylenediamine-adipate salt, 43 g and 1,3,5-trimethyl-2,4,6-tris (3,5- Charge 8 g of di-t-butyl-4-hydroxybenzyl) benzene, and add nitrogen at 1 liter / min.
The mixture was allowed to react at 250 ° C. for 3 hours while flowing in. Then 2
After evaporation of caprolactam gradually reduced to unreacted until Lumpur, was added a solution prepared by dissolving the catalyst pot tetrabutoxyzirconium 8g caprolactam 50g under reduced pressure in the reaction system, 240 ° C., 4 hours at 1 torr It was made to react.
Thereafter, a polyamide elastomer chip was obtained in the same manner as in Example 1.

This elastomer has a soft segment content of 64%, of which polyoxyethylene glycol segment is 80%, a haze number of 7%, a relative viscosity of 2.1, a tensile breaking strength of 300 kg / cm ² , and a Shore hardness of 84 A. Met.

[0056]

Example 13 The same reactor as in Example 1 was charged with polyoxyethylene glycol 2240 having a number average molecular weight of 1490.
g, a number average molecular weight 1830 polyoxytetramethylene glycol 560 g, terephthalic acid 3 01 g, caprolactam 1250 g, antimony trioxide 1g and 1,3,
5-trimethyl-2,4,6-tris (3,5-di-t
-Butyl-4-hydroxybenzyl) benzene (8 g) was charged, and the temperature was 220 ° C while flowing nitrogen at 1 liter / min.
For 2 hours and at 250 ° C. for 2 hours. Then 5
After the pressure was gradually reduced to torr and the unreacted caprolactam was distilled off, a solution of 8g tetrabutoxyzirconium in 50g caprolactam was added to the reaction system from the catalyst pot under reduced pressure and reacted at 250 ° C and 1 torr for 3 hours. Let Thereafter, a polyamide elastomer chip was obtained in the same manner as in Example 1.

This elastomer had a soft segment content of 70%, of which polyoxyethylene glycol segment was 80%, a haze number of 9%, a relative viscosity of 1.9, a tensile breaking strength of 260 kg / cm ² , and a Shore hardness of 79 A. Met.

[0058]

Comparative Example 1 The distillation tube of the reactor of Example 2 was replaced with a reflux condenser, 139 g of caprolactam and 62.9 of sebacic acid.
g, hexamethylenediamine-adipate 8.2 g and pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] 0.4 g were charged, and 2 g of water was added. 250 ℃
And reacted for 5 hours. Then, the pressure was reduced and the unreacted caprolactam was distilled off to obtain a polyamide having carboxyl groups at both ends with a number average molecular weight of 600.

Next, 41 g of this polyamide, 60 g of polyoxyethylene glycol having a number average molecular weight of 1000, 15 g of polyoxytetramethylene glycol having a number average molecular weight of 1830 and 0.23 g of tetrabutoxyzirconium were placed in a reactor similar to that used in Example 2. After charging, the reaction was carried out at 260 ° C. and 1 Torr for 5 hours. The obtained polymer was slightly cloudy and many white foreign matters were recognized. Further, when the polymer was taken out and immersed in water, it became sticky, and it was difficult to collect it because it was hard to solidify even when cooled.

This polyamide elastomer has a soft segment content of 62.5% by weight, of which polyoxyethylene glycol segment is 80% by weight,
Haze number 54%, relative viscosity 1.8, tensile breaking strength 210
It was kg / cm ² and Shore hardness of 85A.

[0061]

Comparative Example 2 2880 g of polyoxyethylene glycol having a number average molecular weight of 1490, 250 g of terephthalic acid, 1300 g of caprolactam, and pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate]. Except for charging 8g,
Polymerization was carried out in the same manner as in Example 1. Then, when it was extracted into water in the form of a strand and cooled, remarkable stickiness was produced and it was difficult to take it out continuously.

This polyamide elastomer had a soft segment content of 72% by weight, the total amount was a polyoxyethylene glycol segment, a haze number of 6%, a relative viscosity of 2.2, a tensile breaking strength of 220 kg / cm ² , and a Shore hardness of 75 A. Met.

[0063]

Comparative Example 3 Polymerization was carried out in the same manner as in Example 3 except that the nitrogen flow rate was set to zero. When the unreacted caprolactam was distilled off, the reaction system became cloudy, and the obtained elastomer had a haze number of 80% and contained many white foreign substances.

[0064]

Comparative Example 4 1920 g of polyoxyethylene glycol having a number average molecular weight of 1490, 480 g of polyoxytetramethylene glycol having a number average molecular weight of 1830, 239 g of adipic acid, 700 g of caprolactam, 800 g of hexamethylenediamine-adipate and pentaerythrityl-tetrakis. Polymerization was carried out in the same manner as in Example 3 except that 8 g of [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] was charged.

The polymer obtained had a soft segment content of 60% by weight, of which 80% of polyoxyethylene glycol segments were contained, a haze number of 76%, a relative viscosity of 1.6, a tensile breaking strength of 120 kg / cm ² , The Shore hardness was 88A.

[0066]

According to the present invention, it has moderate hydrophilicity,
A flexible and transparent polyamide elastomer can be easily obtained, which is preferably used as an antistatic agent for various resins, particularly acrylic resins, and as a material for flexible sheets and films having excellent water vapor permeability. .

Claims (2)

[Claims] 1. (A) a polyamide-forming monomer containing at least 50% by weight of caprolactam, and (B)
A dicarboxylic acid having 6 to 20 carbon atoms and (C) a polyoxyalkylene glycol and at least one diol selected from α, ω dihydroxy hydrocarbons,
A diol having a polyoxyethylene glycol segment content of 30 to 99% by weight and a number average molecular weight of 1000 to 4000 in the diol is placed under an inert gas stream or under a reduced pressure of 100 to 750 torr. At a temperature of 180 to 280 ° C., the reaction is carried out while removing the water generated in the reaction from the system, and then the pressure is reduced to 100 Torr or less to distill off most of the unreacted caprolactam. A method for producing a transparent hydrophilic polyamide elastomer, which comprises adding a titanium alkoxide and / or a zirconium alkoxide and further polymerizing the mixture at a temperature of 220 to 280 ° C. under a reduced pressure of 50 Torr or less. 2. An elastomer obtained by the method according to claim 1, which has a relative viscosity of 1.5 or more, a haze number of 50% or less with a thickness of 1 mm, and a component (C) of 56 to 80% by weight.
A transparent hydrophilic polyamide elastomer characterized by containing.