JP2815260B2 - Fiber manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing fibers.
In particular, the present invention relates to a method for producing fibers used for fishing lines, fishing nets and the like.

[0002]

2. Description of the Related Art Conventionally, as a method for producing fibers, for example, a method shown in FIG. 3 is known (European Patent No. 0 10
4 731).

[0003] Reference numeral 1 in the figure denotes a die for feeding the extrudate 2 into water in a water tank 3. The extrudate 2 is water-cooled while moving in water along the guides 4 and 5, and then becomes a monofilament 6 and is conveyed to the pins 8 and the heating plate 9 via the first take-off roller 7. After the monofilament 6 is drawn in the region on the heating plate 9, it passes through the second take-up roller 10 and takes up
It is wound up by 1. Cooled in a water bath after melt extrusion
Crystallization starts from the surface and stays in a water bath or extends
Partial crystallization state that can be stretched by fine adjustment of time
A certain undrawn yarn is drawn by the pin 8. Table 1 shows the quenching time (seconds), the conditioning time (seconds), the toughness (MPa) when the maximum elongation ratio was changed, and the elongation at break (%) using these methods.

[0004]

[Table 1]

[0005] In Table 1, "quick cooling time" indicates the length of time that the monofilament 6 is in the water tank 4, and "conditioning time" indicates that the fiber 8 is removed after the extrudate 2 leaves the die 1. Shows the total elapsed time before leaving.

[0006]

However, there is a large difference in brittleness and viscosity depending on the crystal state (crystallinity, crystal grain size, degree of orientation), and the crystallization speed is slow (necessary for several days). According to this, the range of the optimum processing temperature and time at the time of drawing is narrow, and it is difficult to control to appropriate conditions in continuous spinning and drawing, and the spinning speed and the draw ratio are limited.

[0007] The present invention has been made in view of the above circumstances, to allow a wider range of allowable processing conditions, to be able to set an arbitrary spinning speed and draw ratio, and to obtain a high-strength fiber with high magnification. It is an object of the present invention to provide a method for producing a fiber that can be used.

The present invention discloses that a thermoplastic resin comprising a homopolymer or a copolymer of hydroxyalkanoates is melt-extruded at 100 ° C. to 180 ° C. by an extruder, and then melt extruded.
Forcibly cooling in a water bath at 80 ° C. to 80 ° C .;
After preheating at 0 ° C. to 170 ° C., stretching at 20 ° C. to 160 ° C., and performing a heat treatment.
A method for producing a fiber, which is performed discontinuously and independently .

In the present invention, for example, the above-mentioned thermoplastic resin is melt-extruded in an extruder at a temperature in the range of 100 ° C. to 180 ° C., crystallized in a water bath at 20 ° C. to 80 ° C., and then stretched in another discontinuous step. It is mentioned. The reason for defining the temperature range in this way is that the melting point and the thermal decomposition temperature differ depending on the resin composition and additives (nucleating agent, plasticizer, etc.), and the low temperature is defined by the melting point and the high temperature is defined by the thermal decomposition temperature. Because it is done. Similarly, the range of the water bath temperature is the temperature at which the crystallization speed is the highest, and is defined by the resin composition and the like. As a result, the non-rolled
Make a drawn yarn.

In the present invention, the stretching step is performed at 100 ° C. to 1 ° C.
After preheating at 70 ° C, it is preferable to stretch at 20 ° C to 160 ° C. Here, the reason why the temperature range of the preheating is defined as described above is that if the temperature is lower than 100 ° C., the molecular fluidity due to the melting of the amorphous portion is small, and the orientation and crystallization do not proceed by the rearrangement of the molecules during stretching. This is because if the temperature exceeds 170 ° C., it melts to the crystal part and breaks due to stretching at a high magnification.

The reason why the temperature range at the time of stretching is specified as described above is that, when the temperature is less than 20 ° C. or more than 160 ° C., the crystallization speed becomes extremely slow, and even if the molecules are aligned, the orientation, This is because immobilization does not proceed.

According to the present invention, a thermoplastic resin composed of a homopolymer or a copolymer of hydroxyalkanoates is melt-spun with an extruder, preheated in a separate step , stretched, and stretched.
By performing heat treatment, the allowable range of processing conditions can be expanded compared to conventional ones, and any spinning speed and draw ratio can be specified.
High strength and high strength fibers can be obtained.

[0013]

【Example】

 (Example 1)

FIG. 1 is a schematic explanatory view showing a part of an apparatus used in the method for producing a fiber of the present invention. 21 in the figure
Is an extruder for feeding the extrudate 22 into the warm water in the water tank 23. 24, 25, and 26 are guides for guiding the extruded product 22,
27 is a take-up roller and 28 is a take-up roller.

FIG. 2 is a schematic explanatory view of an apparatus for drawing a fiber wound by a winding roll of the apparatus shown in FIG. 31 in the figure
Is a delivery roller for feeding the melt spun fiber 32 to the heating furnace 33.
La. In the figure, 34 and 35 are heating rollers, 36 and 37 are heating plates, 38 is a take-up roller, and 39 is a take-up roller. In this embodiment, a fiber is manufactured using such an apparatus as follows.

First, a copolymer of hydroxybutyrate and hydroxyvalerate (PHB / HV = 88/12) is extruded by an extruder 21 into hot water in a water tank 23 at 160 ° C. and melt-spun. Here, the temperature of the hot water in the water tank 23 is kept at 50 ° C. The fibers sent into the warm water are cooled and solidified,
It is wound by a take-up roller 28 via a guide 26 and a take-up roller 27 (see FIG. 1).

Next, as shown in FIG. 2, the present fiber is preheated at 130 ° C. in a separate step, then drawn at 80 ° C. by 8 times, and then heat-treated at 110 ° C. to produce a fiber. as a result,
The breaking strength (MPa) of the fiber was 242 , and the breaking elongation (%) was 138.

Fibers were produced under the same conditions as in Example 1 except that the draw ratio was changed to 9, 10, and 11. The breaking strength (MPa) and breaking elongation (%) of the fibers in these cases are as shown in Table 2 below. As a comparative example, the breaking strength and the breaking elongation at a draw ratio of 1 are also shown.

[0019]

[Table 2]

Thus, according to the above embodiment, the copolymer of hydroxybutyrate and hydroxyvalerate is melt-spun at 160 ° C. by the extruder 21.
Cooling and solidification in hot water at ℃ and preheating at 130 ℃
And stretched 8 to 11 times at 80 ° C and heat-treated at 110 ° C.
By performing this step as a separate step, the allowable range of the processing conditions is broadened as compared with the related art, and it is possible to set any spinning speed and drawing ratio. Therefore, high strength and high strength fibers can be obtained.

[0021]

[Table 3] Table 3 shows the maximum stretching ratio and the breaking state when the stretching temperature was variously changed without performing the preliminary heating.

[0022]

As described in detail above, according to the present invention, the allowable range of the processing conditions is expanded as compared with the conventional one, and the desired spinning speed,
It is possible to provide a method for producing a fiber, which can set a draw ratio and can obtain a fiber with high magnification and high strength.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of a fiber manufacturing apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic explanatory view of an apparatus for stretching a fiber wound by a winding roll of the apparatus of FIG.

FIG. 3 is a schematic explanatory view of a conventional fiber manufacturing apparatus.

[Explanation of symbols]

21: Extruder, 22: Extrudate, 23: Water tank, 27, 38: Take-off
La, 28, 39 ... winding roller, 32 ... fiber, 33 ... heating furnace.

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Yoshihiro Maekawa 200 Matsuo, Hirao, Chogawa-cho, Matsuura-shi, Nagasaki Pref.Matsuura Research Laboratory, Chuko Kasei Kogyo Co., Ltd. 1010, Chuo Chemical Industry Co., Ltd. Yokohama Research Laboratory (56) References JP 2-63055 (JP, B2) JP 2-63056 (JP, B2)

Claims (1)

(57) [Claims] 1. A thermoplastic resin comprising a homopolymer or a copolymer of a hydroxyalkanoate is extruded by an extruder.
After melting and extruding at 00 ° C to 180 ° C, 20 ° C to 80 ° C
Forcibly cooling in a water bath of
After preheating at 0 ° C, stretching at 20 ° C to 160 ° C,
Processing steps, and each step is discontinuously and independently performed.
A method for producing a fiber, wherein the method is performed upright .