JP2001139804A - Copolyamide, fiber and molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain copolyamides which inhibit gelation to reduce the formation of gel even when retained in the molten state under heating for a long period of time. SOLUTION: The copolyamides are obtained by copolymerizing a dicarboxylic acid and/or a diamine and contain titanium oxide having been coated with a metal and/or a metallic compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a copolymerized polyamide,
The present invention relates to a fiber and a molded product comprising the same. More specifically, the present invention relates to a copolymerized polyamide in which gelation is suppressed, a fiber comprising the same, and a molded article.

[0002]

2. Description of the Related Art Polyamide, particularly polyhexamethylene adipamide (hereinafter, nylon 66) is liable to gel when heated and melted, resulting in poor appearance of a molded product due to mixing with a polymer and clogging at a discharge port. It is also the cause. For this reason, various studies for suppressing gelation have been made conventionally.

For example, Japanese Patent Application Laid-Open No. S49-38950 discloses the addition of an appropriate amount of a phosphinic acid compound or a phosphonous acid compound having a specific structure and an alkali compound. However, when a phosphorus compound is added, although there is an effect of preventing gelation, the effect is small, and there is a problem that increasing the amount of addition promotes gelation.

[0004] Japanese Patent Application Laid-Open No. 6-502671 discloses that
A method for copolymerizing -methylpentamethylenediamine is disclosed. However, the copolymerized nylon 66 obtained by copolymerizing 2-methylpentamethylenediamine is less likely to gel than the non-copolymerized nylon 66, but its effect is insufficient and further improvement is required.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems in the prior art, that is, a copolymerized polyamide in which gelation is suppressed even when staying in a heated and molten state for a long time, and gelation is suppressed. The task is to obtain

[0006]

In order to solve the above-mentioned problems, the polyamide of the present invention mainly has the following constitution. That is, it is a copolymerized polyamide obtained by copolymerizing a dicarboxylic acid and / or a diamine, and is characterized by containing titanium oxide coated with a metal and / or a metal compound. Further, the fiber of the present invention mainly has the following configuration. That is, it is a fiber made of the above copolymerized polyamide. The fiber molded product of the present invention mainly has the following configuration. That is, a molded article comprising the above copolymerized polyamide,
It is.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below.
Although the copolymer polyamide of the present invention is not particularly limited, a copolymer polyamide having a basic skeleton of nylon 66 whose main repeating unit is hexamethylene adipamide is preferably used.

[0008] The copolymerized polyamide of the present invention needs to copolymerize a dicarboxylic acid and / or a diamine. When not copolymerizing these copolymer components,
The decomposition of the amide bond cannot be effectively suppressed,
The effect of gel suppression cannot be achieved.

Examples of the dicarboxylic acid include isophthalic acid, terephthalic acid, sebacic acid, and 2,6-naphthalenedicarboxylic acid, and isophthalic acid is particularly preferred in terms of suppressing gelation.

In the copolymerization of a dicarboxylic acid, it is preferable to add an equivalent of a dicarboxylic acid to the dicarboxylic acid to be copolymerized for copolymerization in order to stabilize the amount of terminal groups of the polymer. Hexamethylene diamine is preferably used.

The copolymerization amount of dicarboxylic acid is preferably 0.5 to 5% by weight based on the copolymer. More preferably, it is 1 to 3% by weight. When the copolymerization amount is in such a range, the properties of the polyamide before copolymerization can be sufficiently maintained, and the manifestation of the gel suppressing effect becomes sufficient.

On the other hand, examples of the diamine include isophorone diamine and 1,4-diaminobutane. Isophorone diamine is particularly preferable in terms of suppressing gelation. Upon copolymerization of the diamine, it is preferable to add a dicarboxylic acid and an equivalent amount of a dicarboxylic acid for copolymerization to stabilize the amount of terminal groups of the polymer, and as such a dicarboxylic acid, adipic acid is preferable. Used.

The amount of the diamine to be copolymerized is preferably 0.5 to 5% by weight based on the copolymer. More preferably, it is 1 to 3% by weight. When the copolymerization amount is in such a range,
The properties of the polyamide before copolymerization can be sufficiently maintained, and the manifestation of the gel suppressing effect is sufficient.

Further, in the present invention, the copolymerized polyamide contains
It is important to contain a titanium oxide coated with a metal and / or a metal compound, and if such a specific titanium oxide is not contained, it is possible to effectively suppress radical generation during heating and melting which causes gelation. I ca n’t,
As a result, gelling of the copolymerized polyamide cannot be suppressed.

The metal used for the coating of titanium oxide is preferably Mn, Si, Al, Zn or the like. In the case of a metal compound, the form of an oxide or hydroxide of such a metal is preferably used.

The amount of coating is not particularly limited, but is preferably 5% by weight or less of the weight of titanium oxide to be coated for each metal and / or metal compound. With such a coating amount, agglomeration between the coated titanium oxides can be effectively prevented, and deterioration in the appearance of the molded product and increase in the filtration pressure during spinning can be prevented.

The amount of titanium oxide coated with the metal and / or metal compound is not particularly limited, but is preferably 60% by weight or less based on the copolymerized polyamide. Within this range, the inherent properties of the polyamide resin can be sufficiently exhibited. If the content is within this range, it may be used in combination with titanium oxide having different amounts and types of coated metal and / or metal compound.

The copolymerized polyamide of the present invention is most conveniently used by a known polymerization method, and if necessary, a known light fastening agent, viscosity stabilizer, and electrostatic agent as long as the object of the present invention is not hindered. , Plasticizers, heat stabilizers, pigments, and other polymers (polyethylene, polyester, polypropylene, polycarbonate, ABS resin, modified products thereof, etc.) may be added to the polymer during or after polymerization.

[0019]

EXAMPLES The present invention will be specifically described below with reference to examples. The measurements described in Examples and Comparative Examples were performed according to the following methods. <Relative viscosity: ηr>
The relative viscosity of a 98% sulfuric acid solution of 01 g / mL / 25 ° C. was measured. <Amino end group concentration (μmol / g)> Sample 0.5
g was dissolved in 25 mL of a mixed solution of phenol / ethanol = 84/16% by weight, and the amino terminal group concentration was determined using N / 50 N hydrochloric acid using thymol blue as an indicator. <Geling time> 20 g of a completely dried sample was placed in a 25 mmφ test tube, and was replaced with nitrogen. Under nitrogen seal / 290
C. and sampled every 0.5 hour. 0.1 g of the sample taken out was added to 19.9 g of 65% sulfuric acid, and the dissolution state when stirring at 50 ° C. for 15 hours was observed.
The heat treatment time at which insolubles began to be observed was taken as the gelation time.

Example 1 An equimolar salt of adipic acid and hexamethylenediamine (hereinafter referred to as AH salt) was charged into a 5 L autoclave together with water so as to form an 80% aqueous solution, and then isophthalic acid was used as a copolymer component. Hexamethylenediamine was added in an amount equivalent to 2% by weight based on the copolymer after the copolymerization, and an equivalent amount of added isophthalic acid was added. At the same time, acetic acid 5/1000 mol /
After charging the mol salt, the pressure was increased by heating to 1.7 MPa, and the pressure was controlled until the internal temperature of the autoclave reached 255 ° C. so as to maintain 1.7 MPa. Immediately after the suppression was started, titanium oxide coated with a metal or a metal compound was added in the form of a water slurry. Thereafter, the pressure was released to the atmospheric pressure in one hour. Thereafter, the inside of the autoclave was depressurized to adjust ηr, and then pressurized to discharge the copolymerized nylon 66 onto the strand to form chips. Table 1 shows the results of the evaluation of the obtained polymer.

[0021]

[Table 1]

Example 2 A chip was obtained in the same manner as in Example 1 except that the amount of isophthalic acid was changed to 3% by weight. Table 1 also shows the results of the evaluation of the obtained polymer.

Example 3 A chip was obtained in the same manner as in Example 1 except that isophoronediamine was added as a copolymer component in an amount of 3% by weight based on nylon 66, and an equivalent amount of adipic acid was added. Table 1 also shows the results of the evaluation of the obtained polymer. From Examples 1 to 3, it is understood that the gelation time can be extended by using titanium oxide coated with a copolymer and a metal.

(Comparative Example 1) A chip was obtained in the same manner as in Example 1 except that no copolymerization was carried out and titanium oxide having no metal coating was used. Table 1 also shows the results of the evaluation of the obtained polymer. From the results of Comparative Example 1, it can be seen that the gelation time cannot be extended when titanium oxide having no copolymerization and no metal coating is used.

Comparative Example 2 A chip was obtained in the same manner as in Example 1 except that titanium oxide having no metal coating was used.
Table 1 also shows the results of the evaluation of the obtained polymer. From the results of Comparative Example 2, it is understood that the gelation time cannot be extended only by copolymerization.

[0026]

The polyhexamethylene adipamide of the present invention is excellent in heat resistance and has little gel generation, so that the yarn breakage is small even in melt spinning for a long time, and the appearance is not impaired when it is formed into a molded product.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) D01F 1/02 D01F 1/02 6/80 321 6/80 321B 6/90 301 6/90 301 F term ( Reference) 4F071 AA55 AB06 AB09 AB10 AB18 AE22 AH19 BA01 BC07 4J001 DA01 DB02 DB04 DC14 EB34 EB36 EB37 EB46 EB55 EC07 EC08 EC15 FB03 FB05 FC05 FD01 GA13 JA01 JA10 JC01 4J002 CL031 DA097 DA107 DA136 DE077DE107 DJ117 DE1361 DJ07 JJ05

Claims (6)

[Claims] 1. A copolyamide obtained by copolymerizing a dicarboxylic acid and / or a diamine, wherein the copolyamide comprises titanium oxide coated with a metal and / or a metal compound. 2. The copolymerized polyamide according to claim 1, wherein the dicarboxylic acid is isophthalic acid. 3. The copolymerized polyamide according to claim 1, wherein the main repeating unit of the copolymerized polyamide is hexamethylene adipamide. 4. The method according to claim 1, wherein the amount of the dicarboxylic acid and / or diamine to be copolymerized is 0.5% by weight or more and 5% by weight or less based on the copolymer. Copolymerized polyamide. 5. A fiber comprising the copolymerized polyamide according to claim 1. 6. A molded article comprising the copolymerized polyamide according to claim 1.