JPH06136615A - Production of polyether ester elastomer yarn - Google Patents

Abstract

PURPOSE:To efficiently produce a polyether ester elastomer yarn having excellent characteristics. CONSTITUTION:A polyether ester elastomer containing polyethylene terephthalate and/or polybutylene terephthalate as hard segment and a linear polyalkylene glycol as soft segment is melt-spun at a spinning speed of >=400m/min and, without winding, continuously drawn at a draw ratio(DR) expressed by the following formula and wound while applying a relax of >=5%. (800/sq. rt. sq. rt. V)+1>=DR>=(20/sq. rt. sq. rt. V)+1 [V is spinning speed (m/min)].

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention efficiently manufactures a polyetherester-based elastic yarn having excellent elastic recovery performance which is used as a garment and an industrial material, and has excellent chemical resistance, weather resistance and heat resistance. It is about how to do it.

[0002]

2. Description of the Related Art Heretofore, polyurethane elastic yarns have been generally used as elastic yarns for clothing and industrial materials. However, although the polyurethane elastic yarn has excellent elastic recovery performance, it has the drawback of being inferior in heat resistance, chemical resistance, and weather resistance. In recent years, as a solution to the drawbacks of polyurethane-based elastic yarns, polyetherester-based elastic yarns have been developed that use highly crystalline polyesters such as polyethylene terephthalate and polybutylene terephthalate as hard segments and polyarylene glycol as soft segments. , Various research has been done. In the case of producing a polyetherester-based elastic yarn, it is usually necessary to stretch after melt spinning in order to improve elastic recovery (see, for example, JP-A-56-118911 and JP-A-58-91820). ).

As a method of drawing after melt spinning, a two-step method in which an undrawn yarn is once wound and then drawn and a spin draw method in which the undrawn yarn is continuously drawn without being wound (direct spinning drawing Method), and the latter is preferred for efficient fiber production. However, in the case of the polyetherester-based elastic yarn, if the spin draw method is adopted, there is a problem that unwinding failure due to winding tightness or winding collapse after winding on cheese occurs, and the spin draw method has not been put to practical use. Is the actual situation.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a polyetherester-based elastic yarn having excellent elastic recovery performance, heat resistance, chemical resistance, and weather (light) resistance, which is generally used for the production of polyester fibers for clothing. It is intended to provide a method that can be used and efficiently manufactured.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the inventors have found that melt spinning is performed at a high spinning speed, followed by spinning and stretching at a specific draw ratio. It has been found that this object can be achieved by the above, and has reached the present invention.

That is, the gist of the present invention is as follows. Polyether terephthalate and / or polybutylene terephthalate is used as a hard segment and a linear polyalkylene glycol is used as a soft segment, and a polyether ester-based elastic body is melt-spun at a spinning speed of 400 m / min or more and continuously without winding. And a drawing ratio (DR) represented by the following formula, followed by winding while giving a relaxation of 5% or more. (80 / √V) + 1 ≧ DR ≧ (20 / √V) +1 [V represents a spinning speed (m / min). ]

The present invention will be described in detail below. The polyether ester-based elastic body constituting the elastic yarn of the present invention needs to have polyethylene terephthalate (PET) and / or polybutylene terephthalate (PBT) as hard segments. The ratio of PET to PBT is not particularly limited, but when the PBT is large, the elastic recovery performance is excellent, and when the PET is large, the strength / elongation property is excellent. Therefore, depending on the intended use of the elastic yarn,
PET and PBT may be used alone or as a mixture of both at an appropriate ratio.

On the other hand, a linear polyalkylene glycol is used as the soft segment, but has a molecular weight of 500.
~ 3000 polytetramethylene glycol (PTMG) is the most practical.

The copolymerization ratio of the hard segment and the soft segment is not particularly limited, but when the hard segment is large, the strength / elongation property is excellent but the elastic recovery performance is poor, and when the amount of the soft segment is large, the performance is opposite. Therefore, it is necessary to select the copolymerization ratio according to the purpose of use of the elastic yarn, but the copolymerization ratio (weight ratio) of the hard segment and the soft segment is generally 8/2 to 2/8.

Additives such as antioxidants, pigments, light stabilizers, reinforcing agents, and modifiers may be added as long as the characteristics of the elastic yarn are not impaired.

Next, the spinning speed at the time of melt spinning is 400 m /
It should be more than a minute. If it is less than 400 m / min, the degree of orientation of the spun yarn will be low, and it will be necessary to draw at a high draw ratio in continuous drawing, and yarn breakage will easily occur. Further, when the polymer discharged from the nozzle is cooled when the polymer is taken out at a low spinning speed, the polymer is gently cooled, and the thickness unevenness in the length direction of the yarn increases, which is not preferable. The upper limit of the spinning speed is not particularly limited and can be up to about 3000 m / minute. However, if the final winding speed is too high because of stretching after spinning, problems such as defective winding form occur. Is preferably 2500 m / min or less.

Next, the stretching after spinning must be carried out at the stretching ratio represented by the above general formula. If the draw ratio is smaller than this range, the elastic recovery rate of the obtained drawn yarn is inferior, and since the draw tension is low and uniform drawing is not achieved, the thickness unevenness in the length direction of the yarn becomes large, which is not preferable. . On the other hand, if the draw ratio is larger than this range, the residual elongation of the obtained drawn yarn may be too small to be used as an elastic yarn. That is, when it is used as an elastic yarn, it often covers another fiber while being stretched in a later step or mixes with another fiber, and it is necessary to set the residual elongation to a certain level or more. Is. It is necessary to set the residual elongation according to the purpose, but in order to determine this, it is only necessary to wind the undrawn yarn, draw a strong elongation curve, and set the draw ratio.

The presence or absence of heat treatment during stretching and the heat treatment temperature are not particularly limited, but heat treatment may be preferable in some cases depending on the composition of the polyetherester elastic material used. In addition, depending on the application, heat treatment may be preferable in order to control the heat shrinkage rate. However, when PET is used as the hard segment or when the soft segment ratio is high, it is preferable to perform the heat treatment. preferable. For example, using PET as the hard segment,
The weight ratio of hard segment and soft segment is 5/5
In the case of, the heat treatment temperature is around 150 ° C, and when PBT is used as the soft segment and the weight ratio of the hard segment and the soft segment is 3/7, heat treatment at a heat treatment temperature of around 110 ° C makes the elastic yarn easy to use. You can

Next, at the time of winding, it is necessary to provide relaxation of 5% or more between the stretching roller and the winding roller. If the relaxation rate is less than 5%, it is not preferable because the cheese after winding may be wound tightly, collapsed or unwound. The upper limit of the relaxation rate is not particularly limited, but a maximum relaxation rate of about 20% is possible, and a higher relaxation rate is required as the draw ratio increases and the final winding speed increases.

FIG. 1 is a schematic process diagram showing one embodiment of the method of the present invention. Yarn Y spun from the spinneret 1.
Is cooled by the cold air from the cooling cylinder 2, and the oiling device 3
After being imparted with the oil agent by (1), it is guided to the first godet roller (take-up roller) 4. Then, the first godet roller 4 and the second godet roller (stretching roller) 5 are stretched at a predetermined stretching ratio while being in contact with the heater 6 for heat treatment, and 5% between the second godet roller 5 and the winding device 7. It is wound by the winding device while giving the above relaxation. (The speed of the first godet roller 4 becomes the spinning speed.) The heater 6 for heat treatment may be installed as necessary.

[0016]

When the unstretched yarn is wound up, the polyetherester type elastic yarn is tightly wound, and the unwinding property is remarkably deteriorated. On the other hand, if the undrawn yarn is drawn before being drawn, the tightening is reduced and handling becomes easier. This can be understood from the fact that in the strong elongation curve, the yield point of the undrawn yarn is located on the higher elongation side than that of the drawn yarn. Then, when the spinning speed is increased and the undrawn yarn having advanced orientation is drawn at an appropriate draw ratio according to the spinning speed, winding tightness is almost eliminated. Further, winding with high tension also causes the occurrence of winding tightening, but this can be eliminated by winding while winding it relaxed.

[0017]

EXAMPLES Next, the present invention will be described in detail with reference to examples. The measurement and evaluation methods in the examples are as follows. (1) Intrinsic viscosity [η] Using an equal weight mixture of phenol and ethane tetrachloride as a solvent, measurement was performed at a temperature of 20 ° C. (2) Elastic recovery rate Using Tensilon UTM-4-100 type manufactured by Oriental Co.,
After stretching to 100% or 200% at a sample length of 10 cm and a pulling speed of 10 cm / min, return to the original length at the same speed, and when stretching again, find the length when stress appears, and recover the elasticity by the following formula. I asked for the rate. The number of measurements was 10 and the average value was used. Elastic recovery rate (%) = [(E0-E1) / E0] x 100 E0: Length of extension E1: Length when stress appears when stretched again (3) Fineness Leave the fiber in a relaxed state for 30 minutes After that, a 90 cm-long sample was collected, weighed, and converted into a weight of 9000 m. (4) Tensile strength Tensilon UTM-4-100 type manufactured by Oriental Co.,
The sample length was 10 cm and the tensile speed was 10 cm / min. The number of measurements was 10 and the average value was used. (5) Winding shape 500 g of the drawn yarn was wound, and the winding shape of the obtained cheese was observed, and the ear height and twill drop were observed. In addition, the quality of the winding appearance is
The evaluation was made in two grades of "○: neither twill drop nor ear height, x: at least one of twill drop and ear height". (6) Unwinding The unwound yarn was unwound by hand from the cheese of which the winding shape was observed, and the quality of unwinding was evaluated in two stages of "○: smooth unwinding, ×: catching". . (7) Thickness variation in the length direction The drawn yarn was used as a tubular knitted fabric, and after dyeing with a disperse dye, the presence or absence of shading was visually determined. The determination was performed in three stages of "3: frequent occurrence of shading, 2: slight presence of shading, 1: no shading".

Reference Example 1 Dimethyl terephthalate 19.4 kg, 1,4 in an esterification reaction can
-Butanediol (11.7 kg) was charged, tetrabutyl titanate (catalyst) (10 g) was added, and transesterification reaction was carried out at 210 ° C for 2.5 hours under normal pressure. The obtained reaction product was transferred to a polymerization vessel, 33 kg of PTMG having an average molecular weight of 2000 was added, and then 2
The polycondensation reaction was carried out at a temperature of 50 ° C. for 4 hours under reduced pressure of 1 Torr or less. The polymer obtained had a weight ratio of PBT to PTMG of about 5/5, [η] 2.35 and a melting point (Tm) of 185 ° C. (This polymer is referred to as [P1].)

Reference Example 2 23.5 kg of terephthalic acid and 15.2 kg of ethylene glycol were charged into an esterification reactor and the esterification reaction was carried out at 250 ° C. for 6 hours. The obtained reaction product was transferred to a polymerization vessel, 10 g of tetrabutyl titanate and 33 kg of PTMG having an average molecular weight of 1500 were added, and a polycondensation reaction was carried out in the same manner as in Reference Example 1. The resulting polymer has a PET to PTMG weight ratio of about 5/5,
[Η] was 2.50 and Tm was 223 ° C. (This polymer is referred to as [P2].)

Reference Example 3 Dimethyl terephthalate 27.2 kg, 1,4-butanediol 1
A polymer was obtained under the same conditions as in Reference Example 1 except that 2.6 kg and 19.8 kg of PTMG having an average molecular weight of 2000 were used. The resulting polymer has a PBT to PTMG weight ratio of about 7/3,
[Η] was 2.65 and Tm was 225 ° C. (This polymer is referred to as [P3].)

Examples 1-8, Comparative Examples 1-7 Polymers of [P1]-[P3] were dried under reduced pressure, and then, as shown in FIG.
According to the process of 1. At this time, the spinning temperature was 270 ° C., spinning was carried out from a spinneret having six circular spinning holes with a diameter of 0.5 mm, silicone oil was applied, and the peripheral speed V1 of the first godet roller 4 and the peripheral speed of the second godet roller 5 were increased. The V2 and the temperature T of the heat treatment heater 6 were changed as shown in Table 1, and the discharge amount was adjusted so that the elastic yarn of 50d / 6f was finally obtained. Tables 1 and 2 show the results of evaluation of the strength and elongation of the obtained elastic yarn, the elastic recovery rate, and the winding shape and the unwindability.

[0022]

[Table 1]

[0023]

[Table 2]

The polymers of Examples 9 to 10 and Comparative Examples 8 to 9 [P1] were dried under reduced pressure and then spun into yarn according to the process shown in FIG. 1 (however, the heat treatment heater was turned off).
At this time, the spinning temperature was set to 260 ° C., spinning was carried out from a spinneret having one circular spinning hole with a diameter of 0.5 mm, silicone oil was added, V1 and V2 were changed as shown in Table 2, and the relaxation rate was 8 % And the discharge rate is adjusted to finally reach 50d.
An elastic yarn of 1 / f was obtained. Table 3 shows the results of evaluation of the strength and elongation of the obtained elastic yarn, the elastic recovery rate, the quality of the winding shape, and the degree of thickness unevenness in the length direction.

[0025]

[Table 3]

[0026]

According to the present invention, a polyetherester-based elastic yarn having excellent elastic recovery performance, heat resistance, chemical resistance, and weather (light) resistance is manufactured by using ordinary polyester fiber manufacturing equipment for clothing. It can be manufactured efficiently.

[Brief description of drawings]

FIG. 1 is a schematic process drawing showing one embodiment of the method of the present invention.

[Explanation of symbols]

 1 Spinneret 2 Cooling Tube 3 Oiling Device 4 First Godet Roller 5 Second Godet Roller 6 Heat Treatment Heater 7 Winder

Claims (1)

[Claims] 1. Polyethylene terephthalate and / or polybutylene terephthalate as a hard segment,
Melt-spinning a polyetherester-based elastic body having a linear segment of a polyalkylene glycol as a soft segment at a spinning speed of 400 m / min or more, and continuously with a draw ratio (DR) represented by the following formula without winding. A method for producing a polyetherester-based elastic yarn, which comprises drawing and stretching the fiber while relaxing it by 5% or more. (80 / √V) + 1 ≧ DR ≧ (20 / √V) +1 [V represents a spinning speed (m / min). ]