JP3196460B2 - Method for producing polycyano aryl ether monofilament - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a polycyano aryl ether monofilament. More specifically, the present invention relates to a method for producing a polycyanoaryl ether monofilament having excellent mechanical strength, heat resistance, chemical resistance, and the like, excellent knot strength, and excellent quality without cross-sectional deformation and void inclusion.

[0002]

2. Description of the Related Art Polycyanoaryl ether fibers are excellent in thermoplasticity, heat resistance, chemical resistance, mechanical strength, etc., and take advantage of these characteristics as fibers themselves or as composite materials. Is used in various fields as a matrix precursor or industrial material. For example, as a composite material, a fiber reinforced material or a molded article having a complicated shape is used. Industrial materials are used as fiber materials such as heat-resistant filters, heat-resistant clothing, heat-resistant fabrics (eg, belt conveyors), brushes, fishing lines, and the like. When used as this fiber material,
Not only physical properties such as tensile strength, but also practically important are knot strength. Conventionally, as a method for improving the physical properties of fibers, studies have been made on drawing conditions, atmosphere heating conditions during spinning, and the like, but no studies have been made on knot strength. The knot strength of the heat-resistant resin filament is described in JP-A-2-234913 and JP-A-4-234913.
343710 and "Plastic Age", Masayuki Makihara, 39 (9) , 112 (1993), all of which are directed to polyetherketone (PEEK) fibers, and are therefore disclosed therein. Stretching conditions and spinning conditions that are suitable for the PEEK fiber are selected.

[0003]

Means for Solving the Problems The present inventors have solved the above-mentioned problems of the prior art for polycyano aryl ether fibers, and have found that not only mechanical strength such as tensile strength but also practical use can be tolerated. At the same time, for the purpose of producing a fiber having particularly excellent knot strength, intensive studies have been made especially on spinning conditions. As a result, the reduced viscosity [η _sp /
It has been found that the above object can be achieved by selecting a spinning temperature condition and a surface cooling temperature condition of the spun fiber when spinning a polycyanoaryl ether having c) of 0.5 to 3.0 deciliters / g. The present invention has been completed based on such findings.

That is, the present invention provides a compound represented by the general formula (I)

[0005]

Embedded image

[Wherein, Ar has 6 to 20 carbon atoms and has an aromatic ring in its main chain;

[0007]

Embedded image

A divalent group represented by the formula: And the reduced viscosity [η _sp / c] at 60 ° C. of a 0.2 g / deciliter solution using p-chlorophenol as a solvent is 0.5 to 3.0 deciliters. /
g of the polycyanoaryl ether is melt-spun and drawn to produce a monofilament .
Before performing the immersion treatment with a cooling medium, the spinning temperature in the immersion treatment is set to the melting point (Tm) of the polycyanoaryl ether.
To "Tm + 50 ° C.", wherein the monofilament after spinning in the immersion treatment is cooled such that the temperature difference between the surface temperature and the cooling medium temperature is 150 to 300 ° C., thereby producing a polycyano aryl ether monofilament. It provides a method.

First, in the present invention, the polycyano aryl ether has the general formula (I)

[0010]

Embedded image

[In the formula, Ar has 6 to 20 carbon atoms and has an aromatic ring in the main chain;

[0012]

Embedded image And a divalent group represented by And a reduced viscosity [η _sp / c] of 0.5 to 3.0 deciliters / g, preferably 0.6 to 2.0 deciliters / g.
Is a compound. Here, the reduced viscosity [η _sp / c]
Is a value at 60 ° C. using p-chlorophenol as a solvent. If the reduced viscosity [η _sp / c] is less than 0.5 deciliters / g, the average molecular weight is small, and excellent mechanical strength and heat resistance cannot be obtained. Viscosity increases, making molding difficult. Then, in the repeating unit represented by the general formula (I),

[0013]

Embedded image

The cyanophenylene group represented by the formula is preferably a group represented by the formula:

[0015]

Embedded image

## EQU1 ##

In the polycyano aryl ether having a repeating unit represented by the general formula (I), Ar represents a compound represented by the formula:

[0018]

Embedded image

Preferably, Ar is represented by the formula

[0020]

Embedded image

The general formula (II)

[0022]

Embedded image

Containing at least 80 mol% of a repeating unit represented by the formula: and 0.2 g / p-chlorophenol as a solvent.
Reduced viscosity [η _SP / c] of dl concentration solution at 60 ° C
Is preferably 0.5 to 3.0 dl / g.
Here, the content of the repeating unit represented by the general formula (II) is 8
If it is less than 0 mol%, it may be amorphous,
Those having 0 mol% or more are preferably used. This general formula (I
The polycyano aryl ether having a repeating unit represented by I) may be a copolymer containing other repeating units in a range of less than 20 mol%.

The polycyano aryl ether having the above-mentioned characteristics is constituted such that the repeating unit represented by the general formula (I) is linearly, or randomly or regularly, linearly continuous. Both ends are hydrogen, halogen or formula

[0025]

Embedded image

[Wherein, X represents a halogen atom. ] Is blocked by the terminal group represented by

Among the above polycyanoaryl ethers, for example, a polycyanoarylether (polyether nitrile) having a repeating unit of the general formula (II) can be produced as follows. That is, the general formula (III)

[0028]

Embedded image

[In the formula, X represents a halogen atom. A dihalogenobenzonitrile represented by the general formula (IV)

[0030]

Embedded image

[Wherein, M represents an alkali metal atom. ]
By reacting, in a neutral polar solvent, an alkali metal salt of resorcin represented by the general formula (I) and optionally an alkali metal salt of a divalent phenol having Ar in the general formula (I) as an aromatic skeleton. Can be. Where the general formula (II
As the dihalogenobenzonitrile represented by I), for example, 2,4-dichlorobenzonitrile; 2,4-difluorobenzonitrile; 2,6-dichlorobenzonitrile; 2,6-difluorobenzonitrile and the like are preferably used. Can be In the reaction, one or more of these compounds can be used. As the alkali metal salt of resorcin represented by the general formula (IV) and the alkali metal salt of the divalent phenol, a sodium salt or a potassium salt is preferably used. The polycyanoaryl ether thus obtained has a repeating unit represented by the general formula (II) and satisfies the above condition of the reduced viscosity [η _sp / c].

The polycyanoaryl ether monofilament of the present invention is obtained by melt-spinning and stretching the above-mentioned polycyanoaryl ether from a nozzle.
The target polycyanoaryl ether monofilament can be obtained by setting the spinning temperature and the cooling temperature of the monofilament after spinning to specific conditions when melt-spinning the above polycyanoaryl ether. First, in the present invention, the polycyano aryl ether is melt-spun and a monofilament is manufactured. For example, as a nozzle, to manufacture a monofilament of 0.1 to 2 mmφ, the nozzle diameter is 0.5 to 5 mm.
φ, preferably 1 to 4 mmφ is used. If the nozzle diameter is less than 0.5 mmφ, the pressure of the spinning machine will be too high during operation of the apparatus, and stable spinning may not be performed, and it may be difficult to manufacture the nozzle. On the other hand, 5m
If it exceeds mφ, the draft ratio becomes large, and it becomes difficult to draw. Although there is no particular limitation on the shape of the nozzle, it may be a simple circular tube as described above. However, at the time of quenching, the use of an annular (for example, a double tube) nozzle is effective in preventing cross-sectional deformation and void generation. It is. This double tube nozzle has a polymer (polycyano aryl ether) flow path and a gas (gas) flow path, and the gas flow path is provided at a more central portion in a cross section than the polymer flow path. . In this way, by forming a double pipe, voids gather at the center due to the effect of the wake of the inner pipe, forming a cavity and absorbing the stress of deformation, which is effective in preventing cross-sectional deformation and void generation it is conceivable that. In addition, even if gas is not blown into the inner tube, that is, even if the annular nozzle is used, the incorporation of voids can be prevented, but if gas is blown into the inner tube, the cavity becomes large and a tubular monofilament can be obtained. At this time, as the blowing gas,
An inert gas or air can be used, but an inert gas such as nitrogen is preferably used from the viewpoint of preventing deterioration of the polycyanoaryl ether. And it is effective if the temperature of the gas is set close to the spinning temperature of the polycyano aryl ether to be used.

Next, in the present invention, when the polycyanoaryl ether is melt-spun using the above nozzle to produce a monofilament, the spinning temperature of the melt-spinning conditions is adjusted to the melting point (T.sub.T) of the polycyanoarylether.
m) to “Tm + 50 ° C.” (temperature higher than melting point by 50 ° C.),
Preferably, it is in the range of Tm to “Tm + 40 ° C.”. If the spinning temperature is lower than Tm, the viscosity of the polymer at the time of spinning increases, and the pressure loss increases. In addition, the monofilaments are liable to undergo cohesive breakage, which makes it difficult to spin.
On the other hand, when the spinning temperature exceeds “Tm + 50 ° C.”, thermal decomposition and gelation of the polycyanoaryl ether occur, causing yarn breakage, and making it impossible to stably spin for a long time. In addition, capillary breakage occurs, and it may not be possible to draw the string, which is not preferable. Here, in order to carry out spinning by adjusting the spinning temperature to Tm of the polycyanoaryl ether to “Tm + 50 ° C.”, it is only necessary to attach a heating device to the nozzle and spin while controlling the temperature. Needless to say, a monofilament can be obtained without attaching a heating device to the nozzle, but in this case, it is necessary to raise the temperature of the portion other than the nozzle, which may cause thermal degradation of the polymer. For this reason, it may not be possible to stably mold for a long time. Further, precise temperature control of the nozzle cannot be performed, which causes a non-uniform diameter of the obtained monofilament.

After being melt-spun in the above temperature range, it is drawn.
Before the treatment, a dipping treatment with a cooling medium is performed. The monofilament is cooled so that the spinning temperature in the immersion treatment becomes a specific value . In addition , the surface temperature of the monofilament, the temperature of the cooling medium, and the temperature difference therebetween become important. That is, the spinning temperature in the immersion treatment is suitably from “glass transition temperature (Tg) + 20 ° C.” to Tm. If the spinning temperature in this immersion treatment is lower than “Tg + 20 ° C.”, the effect of rapid cooling does not appear, and crystals are generated before cooling, so that uniform stretching in the subsequent step cannot be performed, and the knot strength decreases. I do. On the other hand, if it exceeds Tm, yarn breakage will occur during the production of the filament, and large deformation of the yarn cross section and entrainment of voids will be observed, which is not preferable. On the other hand, the temperature of the cooling medium is desirably cooled below Tg. If it exceeds Tg, the effect of rapid cooling does not appear, and no improvement in nodule strength is observed. Although the cooling temperature is preferably low, it is preferably 0 ° C. or higher from the viewpoint that a cooling device is required. And in the immersion process
The temperature difference between the surface temperature of the monofilament after spinning and the temperature of the cooling medium is 150 to 300 ° C., preferably 16 to 300 ° C.
0-280 ° C. If this temperature difference is less than 150 ° C,
An air cooling step is required before immersion in the cooling medium. Alternatively, the cooling medium must be heated to a high temperature, and crystallization proceeds, which adversely affects the improvement of the knot strength, which is not preferable. On the other hand, if the temperature difference exceeds 300 ° C., the deformation of the cross section of the monofilament or the inclusion of voids is caused by thermal strain, which is not preferable. The cooling medium used to obtain such a temperature difference is not particularly limited,
It is desirable to use a liquid in terms of the heat transfer coefficient. 0-9
In the low temperature region of 0 ° C., water is most easily handled and suitable.
On the other hand, on the high temperature side of 90 ° C. to Tg, for example, ethylene glycol is suitable.

The monofilament obtained by melt-spinning under the above-mentioned temperature and cooling conditions is then subjected to a drawing treatment to obtain a desired monofilament. Here, among the stretching treatment conditions, the stretching temperature is usually from Tg to
It is desirable to process in the range of “Tm−20 ° C.”. As the stretching temperature, cold stretching below Tg is possible, but Tg or more is desirable from the viewpoint of controlling the stretching ratio and preventing whitening during stretching. On the high-temperature side, when the temperature is close to Tm, the material is melt-ruptured during stretching or stretch stress is not applied, and the effect of stretching is lost. Therefore, the temperature is preferably "Tm-20C" or less. More preferably, “Tg + 10 ° C.” to “Tm-40”
° C ”. The stretching ratio is usually 2 to 7 times, preferably 3 to 6 times, and the elongation of the stretched monofilament in a tensile test is desirably 40 to 5%. If the stretching ratio is too small, the strength at the time of knotting is increased, but the tensile strength is reduced, and it cannot be put to practical use. On the other hand, when the stretching ratio is too large, not only breakage of the monofilament occurs at the time of stretching, but also the elongation of the stretched monofilament becomes small, and the once increased knot strength may decrease. The stretching treatment may be performed in one stage under the above treatment conditions, or may be performed in two or more stages a plurality of times. Economically, one- or two-stage treatment is usually preferred. Further, after stretching, if necessary, treatment at 180 to 300 ° C. (annealing)
May be. The polycyano aryl ether monofilament obtained as described above has a tensile strength of 4 (g / g).
d) or more, the knot strength is 2 (g / d) or more, which is excellent in mechanical strength and knot strength, and can be effectively used for composite materials or industrial materials.

[0036]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. Example 1 The polycyano aryl ether used has the formula

[0037]

Embedded image

A compound having a repeating unit represented by the formula: reduced viscosity [η _sp /c]=1.0 deciliter / g, T
g = 145 ° C. and Tm = 340 ° C. The above polycyano aryl ether was melt-spun at a melting temperature of 360 ° C. using an extruder equipped with a nozzle of 3 mmφ, and 1.2
A monofilament of mmφ was obtained. The monofilament was wound at a room temperature of 25 ° C. 2 m away from the nozzle. It was cooled in a water tank containing hot water at 65 ° C. at a position 75 cm from the nozzle. The surface temperature of the monofilament immediately before the cooling water tank was 253 ° C. In addition, the surface temperature of the monofilament was measured using a contact type thermometer manufactured by Anritsu Corporation. Next, the monofilament was drawn at 200 ° C. at a draw ratio of 5.1 times to obtain a 530 μm monofilament. Some of the monofilaments were annealed at 240 ° C. About the obtained monofilament, tensile strength (g / d), elongation (%)
And knot strength (g / d) were measured. Table 1 shows the results.

Comparative Example 1 The same polycyano aryl ether as in Example 1 was melt-spun in the same manner as in Example 1 to obtain a monofilament of 1.2 mmφ. The monofilament was wound at room temperature 25 ° C. The surface temperature of the monofilament at the time of winding was 110 ° C. Next, the monofilament was stretched at 200 ° C. at a stretching ratio of 4.8 times to
m monofilaments were obtained. Some of the monofilaments were annealed at 240 ° C. About the obtained monofilament, tensile strength, elongation, and knot strength were measured. Table 1 shows the results.

[0040]

[Table 1]

Examples 2-1 to 4 and Comparative Examples 2-1 to 2 The polycyanoaryl ether used had a reduced viscosity [η
_sp / c] = 1.2 deciliters / g, Tg = 146 ° C. and Tm = 340 ° C. The above polycyano aryl ether was mixed with a double-tube nozzle shown in FIG.
The melt spinning was performed at a melting temperature of 363 ° C. using an extruder equipped with an inner diameter of 1.2 mmφ. The filament take-off speed (110 m / min) was kept constant, and nitrogen gas was blown into the inner tube of the double tube nozzle so that the same monofilament having a reduced yarn diameter of 791 μm was obtained as shown in Table 2. Melt spinning was performed under the conditions. Note that 45 ° C. water is used for cooling, and the cooling position indicates the distance from the nozzle. Next, the obtained monofilament was heated at 220 ° C.
And stretched at a stretch ratio of 4.1 times. About the obtained monofilament, tensile strength, elongation, and knot strength were measured. Table 3 shows the results.

[0042]

[Table 2]

[0043]

[Table 3]

Example 3 and Comparative Example 3 Using the same polycyano aryl ether as in Example 2,
Using an extruder equipped with a nozzle having a diameter of mmφ, the melt spinning was performed in the same manner as in the cooling method under the conditions shown in Table 4, and the spun monofilament was immersed in water at 45 ° C. and wound up. Then
The monofilament was drawn at 220 ° C. at a draw ratio of 3.9. About the obtained monofilament, tensile strength, elongation, and knot strength were measured. Table 5 shows the results.

[0045]

[Table 4]

[0046]

[Table 5]

Example 4 and Comparative Example 4 Using the same polycyano aryl ether as in Example 2,
Using an extruder equipped with a 0 mmφ nozzle, melt spinning was performed under the conditions shown in Table 6 to wind up a monofilament.
Ethylene glycol was used as a cooling medium, and the cooling position was 75 cm from the nozzle. Then
The obtained monofilament was stretched at 280 ° C. at a draw ratio of 4.
The film was stretched by a factor of one. About the obtained monofilament, tensile strength, elongation, and knot strength were measured. Table 7 shows the results.

[0048]

[Table 6]

[0049]

[Table 7]

[0050]

According to the production method of the present invention, a monofilament excellent in mechanical properties, heat resistance, chemical resistance and knot strength can be obtained. Therefore, the monofilament obtained according to the present invention is used as a composite material for a fiber-reinforced material or a molded article having a complicated shape, and as an industrial material, a heat-resistant filter, a heat-resistant garment, a heat-resistant woven fabric (for example, a belt conveyor). Etc.), a brush or a fishing line can be effectively used.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional end view of a double tube nozzle used in Example 2.

FIG. 2 is a cross-sectional view of a double tube nozzle used in Example 2.

[Explanation of symbols]

 P: Polymer G: Inert gas Di: Inner tube outer diameter of double tube nozzle (1.2 mmφ) Do: Outer tube inner diameter of double tube nozzle (3 mmφ) 1: Polymer channel 2: Gas channel

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-174419 (JP, A) JP-A-61-231219 (JP, A) JP-A-63-28914 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) D01F 6/66 D01D 5/088

Claims (1)

(57) [Claims] 1. A compound of the general formula (I) [Wherein, Ar has 6 to 20 carbon atoms, has an aromatic ring in the main chain, and has the formula: And a divalent group represented by And a repeating unit represented by the formula (1), and p-chlorophenol is used as a solvent.
In producing a monofilament by melt-spinning and drawing a polycyanoaryl ether having a reduced viscosity [η _sp / c] of 0.5 g / d of 3.0 d / g of a 2 g / dL solution at 60 ° C./g , Before cooling medium
And the spinning temperature in the immersion treatment is set to the melting point (Tm) of the polycyano aryl ether to “Tm + 5”.
And 0 ℃ ", the temperature difference between the monofilament after spinning, and its surface temperature cooling medium temperature in the immersion treatment is 150
A method for producing a polycyano aryl ether monofilament, which is cooled to a temperature of about 300 ° C.