JPH0137486B2 - - Google Patents

Description

[Detailed description of the invention]

<Technical Field> The present invention relates to a method for producing polyamide fibers that facilitates the production of irregular cross-section fibers or hollow fibers. <Prior art> In order to improve the stain resistance, gloss, and bulkiness of polyamide fibers for carpet applications, etc.,
Although irregular cross-section fibers or hollow fibers are used, in order to increase the degree of irregularity or hollowness during production,
Low temperature spinning or high viscosity polymer spinning is required. However, in the former method, an extreme decrease in the spinning temperature impairs the spinning properties, and in the latter method, the productivity of polymerization and spinning is disadvantageous. <Objective> The object of the present invention is to provide a method for producing polyamide fibers that can produce irregular cross-section yarns with a high degree of irregularity or hollow fibers with a high hollowness ratio using a low viscosity polymer without drastically lowering the spinning temperature. It is in. <Solution Means> As a result of intensive studies to achieve the above object, the present inventors surprisingly found that by copolymerizing a polyamine compound containing a specific secondary amino group, the spinning temperature did not decrease. It was discovered that polyamide fibers with high irregularity or high hollowness can be produced using low viscosity polymers. Thus, according to the present invention, when spinning polyamide irregular cross-section fibers or hollow fibers, a polyamine compound represented by the following general formula () is copolymerized as a polymer to add secondary amino groups to 20
A method for producing a polyamide fiber, characterized by using a copolyamide containing ~100meq/Kg. _H2N (-( _CH2 ) _-2NH )-nH...() (where n is an integer from 2 to 8) is provided. The copolyamide used in the present invention has both terminals represented by the following general formula () H ₂ N (-(CH ₂ )- ₂ NH)-nH ... () (where n is an integer from 2 to 8). A polyamine of a primary amine can be produced by addition copolymerization before the polyamide polycondensation is completed. Here, as the polyamine compound, for example, the following compounds are preferably used.・Diethylenetriamine H ₂ N—(CH ₂ ) ₂ —NH—(CH ₂ ) ₂ —NH ₂・Triethylenetetramine H ₂ N—(CH ₂ ) ₂ —NH—(CH ₂ ) ₂ —NH—(CH ₂ ) ₂ ―NH ₂・Tetraethylenepentamine H ₂ N—(CH ₂ ) ₂ ―NH—(CH ₂ ) ₂ ―NH—(CH ₂ ) ₂ ―NH—(CH ₂ ) ₂ ―NH ₂・Heptaethyleneoctamine H ₂ N― (CH ₂ ) ₂ ―NH― (CH ₂ ) ₂ ―NH― (CH ₂ ) ₂ ―NH― (CH ₂ ) ₂ ―NH― (CH ₂ ) ₂ ―NH― (CH ₂ ) ₂ ― NH-( _CH2 ) _{2 -} NH2Additionally, when a polyamine compound is added alone, the polymerization rate decreases due to the terminal blocking effect, so dicarboxylic acids such as succinic acid, glutaric acid, terephthalic acid, sebacic acid, adipic acid, etc. It is preferable to use them together. The amount of the above-mentioned polyamine compound copolymerized in such a copolymer varies depending on the type of polyamine compound used, but the amount of secondary amino groups in the resulting copolyamide is 20 to 100 meq/Kg.
It is necessary to make the amount such that When it is less than 20 meq/Kg, the effect of improving the degree of irregularity and hollowness is small, while when it exceeds 100 meq/Kg, the resulting yarn tends to be weak. When spinning such a copolyamide into irregular cross-section fibers and hollow fibers, for example, Fig. 1 and Fig. 2
Although there is a cross section as shown in the figure, the present invention is not limited thereto. Figure 1 shows an example a in which a circular hollow portion 1 is provided in each hollow fiber, an example b in which three rectangular hollow portions 1' are provided in each hollow fiber, and an example b in which three rectangular hollow portions 1' are provided.
This is an example c in which four rectangular hollow portions 1' are provided. or,
Figure 2 shows triangular cross sections a,
Examples of trilobal b and hexalobal c are shown. In the present invention, the polyamide that serves as the base material to which the polyamine compound is added and copolymerized includes ordinary polyamides such as nylon 6, 8, 12, 310, and 66, copolymers of polyamides with other polymers, and mixtures thereof, but are not particularly limited thereto. <Functions/Effects> In the present invention, as described above, a specific polyamine compound is copolymerized to introduce -NH- groups that are not involved in amide bonding into the main chain of polyamide, and the concentration thereof is 20 to 100 meq. /Kg, we succeeded in producing irregularly shaped yarns and hollow fibers, particularly in achieving a high degree of irregularity and a high hollowness ratio. The effect of improving the degree of irregularity or hollowness by such copolymerization of a specific polyamine compound is still unknown and will be clarified in the future, but it can be estimated as follows.
As a result of the secondary amino group of the polyamine compound introduced into the polymer main chain having hydrogen bonding ability,
It is thought that an interaction different from the normal interaction between polymers occurs, and as a result, the polymer surface tension changes during melting and cooling, contributing to an improvement in the degree of irregularity and hollowness ratio. <Examples> The present invention will be explained below using examples. Example 1 A nylon hexapolymer with an intrinsic viscosity of 1.17 was obtained by mixing ε-caprolactam and the additives shown in Table 1, polymerizing it according to a conventional method, washing with hot water, and drying it at a spinning temperature.
The hollow fiber was wound at 240°C at a spinning speed of 1000 m/min and stretched to 3.2 times to obtain an 830 denier 46 filament hollow fiber of the type shown in Fig. 1b, and its hollow ratio and fiber quality were measured. The results are shown in the table. From the same table, it can be seen that polyamide copolymerized with the polyamine compound of the present invention and having a secondary amine concentration of 20 to 100 meq/Kg not only has an improved hollow ratio but also has a practical hollow fiber in terms of strength and elongation. It turns out that you can get it.

[Table] Example 2 The spinning temperature of the nylon hexapolymer obtained in Example 1
It was wound at 250°C and a spinning speed of 1000 m/min and stretched 3.3 times to obtain a 1300 denier 68 filament irregular shaped yarn of the type shown in Figure 2b.The irregularity and yarn quality were measured. The results are shown in Table 2, and it can be seen that according to the present invention, irregularly shaped yarns having a high degree of irregularity and homogeneous physical properties can be obtained.

【table】

【table】 [Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an example of a hollow fiber spun according to the present invention, and FIG. 2 is a cross-sectional view showing an example of a hollow fiber similarly spun according to the present invention. 1,1'...Hollow part.

Claims (1)

[Claims] 1. When spinning polyamide irregular cross-section fibers or hollow fibers, a polyamine compound represented by the following general formula () is copolymerized to add secondary amino groups in the molecule at 20 to 100 meq/Kg. A method for producing a polyamide fiber, characterized by using a copolymerized polyamide containing the copolyamide. H ₂ N(−(CH ₂ )− ₂ NH)−nH …() [However, n is an integer from 2 to 8]