JPS5836090B2 - Wet spinning method of poly(2,6-diphenyl-1,4-phenylene oxide) - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wet spinning method for poly(2,6-diphenyl-1,4 phenylene oxide).

Conventionally, various proposals have been made regarding wet spinning methods for 2',6-substituted baraphenylene ethers.

For example, in Japanese Patent Publication No. 43-8983, poly(2
．． 6-dimethyl-1,4-phenylene oxide) as an aliphatic halogenated hydrocarbon, especially chloroform solvent, and a method of spinning using ethanol, acetone, or a mixture of these and chloroform as a coagulating liquid;
Furthermore, in Japanese Patent Publication No. 44-28249, poly(2,6-
A method of spinning diphenyl-1,4-phenylene oxide) using methylene chloride as a solvent and isopropyl alcohol as a coagulating liquid is disclosed.

However, both methods use poly(2) with a high degree of polymerization.
．． When applied to the spinning of 6-cyphenyl-1,4-phenylene oxide), there were problems in that the dissolution operation to obtain a concentrated solution suitable for spinning became difficult and the spinnability decreased. .

That is, [η] is 0.8 or more (chloroform, 25°C
(intrinsic viscosity), the dissolution rate of the polymer in the solvent decreases and it takes time to obtain a homogeneous solution, and the application conditions for spinning are limited to a narrow range, and variations in spinning conditions occur during the spinning operation. This increased the chances of yarn breakage, making spinning operations difficult.

As a result of intensive studies to improve these drawbacks, the present inventors found that by using mainly N-methylpyrrolidone as a solvent and mainly water as a coagulating liquid, a polymer with [η] of 0.8 or more was produced. It was discovered that the method can also be applied to spinning, and the present invention was achieved.

That is, the present invention involves dissolving PoIJ (2.6-diphenyl-1,4-phenylene oxide) in N-methylpyrrolidone or a mixed solvent mainly composed of N-methylpyrrolidone, extruding it into a gas, and then aqueous coagulation. The present invention relates to a wet spinning method for poIJ (2.6-diphenyl-1,4-phenylene oxide), which is characterized by passing it through a liquid.

PolyJ (2.6-diphenyl-1,4-phenylene oxide) used in the method of the present invention is not particularly limited in its degree of polymerization, but [η] is 0.8 or more (chloroform at 25°C). It can also be applied to polymers with a high degree of polymerization that are difficult to spin using conventional wet spinning methods (intrinsic viscosity).

The solvent used is N-methylpyrrolidone, but in some cases aromatic and aliphatic halogenated hydrocarbons such as chlorobenzene, 0-dichlorobenzene, methylene chloride, chloroform, and tetrachloroethane, and aromatic carbonates such as benzene, toluene, and styrene. Hydrogen, dioxane, tetrahydrofuran, etc. may be added.

The appropriate amount of these hydrocarbons to be used is up to the same amount as N-methylpyrrolidone.

The spinning stock solution was poIJ (2.6-diphenyl-1,
4phenylene oxide) in N-methylpyrrolidone or a mixed solvent mainly composed of N-methylpyrrolidone.

The concentration of the polymer in the solvent varies depending on the degree of polymerization of the polymer, but is generally preferably in the range of 20 to 4 wt%.

At a concentration below this lower limit, the spinning dope extruded from the spinneret has poor spinnability, making it difficult to form filaments.

At a concentration above this upper limit, the entire spinning dope undergoes rapid gelation and becomes transparent.

Further, the temperature of the spinning dope needs to be maintained at 60° C. or lower.

At temperatures above this temperature, the spinning dope undergoes gelation and devitrification.

Note that the spinning dope is subjected to filtration, defoaming treatment, etc., as necessary.

The spinning dope thus prepared is extruded into gas through a spinneret.

As the gas, a non-solidifying gas such as air or nitrogen is used.

In the method of the present invention, it is an important step that the filament extruded through a spinneret is run through a gas and then passed through a coagulation liquid to effect coagulation.

This is because, if the filament is introduced directly into the coagulation liquid without being passed through the gas, only a thick, devitrified and brittle filament can be obtained.

The travel distance of the filament in gas is, for example, approximately 1 to 50.

The temperature of the gas is suitably about room temperature.

The threads extruded into the gas are then introduced into an aqueous coagulation liquid.

This aqueous coagulation liquid dissolves and removes a solvent such as N-methylpyrrolidone contained in the filaments to coagulate the filaments.

As the aqueous coagulating liquid, water, an aqueous solution of calcium chloride, lithium chloride, sodium sulfate, etc., an aqueous solution of N-methylpyrrolidone, methanol, ethanol, acetone, etc. can be used.

The temperature range is suitably from room temperature to boiling point.

The filamentous body that has come out of the coagulation liquid is wound up at a high speed, and according to the method of the present invention, it is possible to wind up the filament at a speed of 200 m/min or more.

The winding speed of the filament, that is, the draw ratio, relative to the linear speed at which the spinning stock solution is extruded through the spinneret, that is, the draw ratio, can be up to about 100 times, so stable spinning can be achieved under the normally practiced spinning conditions at a draw ratio of about 40 to 50. is carried out, and almost no thread breakage occurs.

As described above, by carrying out the method of the present invention, even if polyIJ (2,6-diphenyl-1,4 phenylene oxide) with a high degree of polymerization is used, spinning can be performed at a high draw ratio. The filaments have high strength and can be spun into extremely fine filaments.

Next, the present invention will be explained by examples.

Note that [η] in the examples indicates the intrinsic viscosity of chloroform at 25°C.

Example 1 Poly(2,6-diphenyl 1,4-
phenylene oxide) and 64.5 g of N-methylpyrrolidone solvent. ! After almost dissolving in i' for 20 minutes, the dissolution operation was continued for another 2 hours to completely dissolve.

This spinning stock solution is passed through a spinneret with a diameter of 0.2 mm and 10 holes into the air at a speed of 0. It was extruded at a rate of 78 WLl/min.

Bring the threads to room temperature. After running 9 crrL in the air, 20
It was introduced into a water tank with a length of 2 m containing a water coagulating solution at °C and coagulated, and then wound up at a speed of 100 m/min.

The stretching ratio under these conditions was 40, the single fiber fineness of the obtained filament was 3d, and the strength was o. sg/d, and the elongation was 5φ.

Example 2 The same spinning dope used in Example 1 was prepared using a spinning dope with a diameter of 0. 2mm
From a spinneret with 25 holes to air at a speed of 1.83 mm/mi
It was extruded at a rate of n.

After running the filament for 4.5 crrL in room temperature air, 2
It was introduced into a 2 m long water tank containing a water coagulation solution at 0° C. to solidify it, and then wound up at a speed of 170 m/min.

The stretching ratio under these conditions was 73, and the single fiber fineness and ld1 strength of the obtained filament were O. 'i'/d, elongation was 6%.

Example 3 The same spinning dope used in Example 1 was prepared with a diameter of 0.2 tra.
y, velocity 1.83 il in air from a spinneret with 25 holes.
It was extruded at a rate of /min.

After the filament was run in the air for 4.5 minutes, it was introduced into a 2 m long water tank containing a 30 wt % calcium chloride aqueous solution to solidify it, and then wound up at a speed of 150 m/min.

Under these conditions, the drawing ratio was 65, and the single fiber fineness of the filament obtained was 2d and the strength was 0. i/d, elongation was 5φ.

Example 4 Poly(2,6-diphenyl-1,4
-Phenylene oxide) 315+ was completely dissolved in 69 g of N-methylpyrrolidone-benzene mixture solvent (1:1 vol). It was extruded into air from a spinneret with 10 2 am holes at a rate of 0.78 ml/min.

After running the filamentous body in the air for 9 cIrL, it was introduced into a water tank containing a water coagulation solution at 20°C and solidified, at a speed of 88 m/m.
It was wound up at a rate of in.

Under these conditions, the stretching ratio was 35, the single fiber fineness of the obtained filament was 3d, and the strength was 0.7g/d1, and the elongation was 5φ.

Example 5 Poly(2,6-diphenyl-1,4-
Phenylene oxide) 24,! A spinning stock solution in which il was dissolved in 76 g of N-methylpyrrolidone solvent was prepared into a spinning solution with a diameter of 0.2 mm.
From a spinneret with 25 holes into the air at a speed of 1. 6 7 m
It was extruded at a rate of //min.

After running the filament for 7 crrL in air at room temperature,
It was introduced into a water tank with a length of 2 m containing a water coagulating liquid at .degree. C. for solidification, and then wound up at a speed of 20 m/min.

The stretching ratio under these conditions was 9.4, the single fiber fineness of the obtained filament was 8 d, the strength was 0.9 g/d, and the elongation was 5 φ.

For comparison, the polymer having [η] of 2.0 was dissolved in methylene chloride, chloroform, or benzene, but a uniform solution could not be obtained and spinning could not be performed.

Claims (1)

[Claims] 1. Poly(2,6-diphenyl-1,4-phenylene oxide) is dissolved in N-methylpyrrolidone or a mixed solvent mainly composed of N-methylpyrrolidone and extruded into a gas.
The poly(2,6
-diphenyl-1,4-phenylene oxide) wet spinning method.