JPH0373652B2 - - Google Patents

Description

[Detailed description of the invention]

(a) Industrial Application Field The present invention relates to a method for producing poly(aryletherketone) fibers. More specifically, fibers made of high-performance poly(aryletherketone) with excellent heat resistance and chemical resistance are drawn and heat treated to have sufficient mechanical potential (especially high silk factor) as industrial fibers. The present invention relates to a method for producing fibers with stable drawability. (b) Prior art Poly(aryletherketone) is a crystalline super heat-resistant thermoplastic resin, and has excellent heat resistance, hydrolysis resistance, (chemical) resistance, electrical properties, radiation resistance, etc. It is known that these useful properties are being utilized in fields such as engineering plastics and films, which are being developed. In the 1980s, ICI began marketing poly(aryletherketone) of formula (1) below under the name polyetheretherketone (hereinafter abbreviated as PEEK), and its manufacturing method and properties are well known. (For example, Japanese Patent Publication No. 60-32642, U.S. Patent No. 4320224)
issue) This PEEK polymer has a glass transition temperature (Tg) of 143
℃, has a melting point (Tm) of 334℃. Further, the poly(aryletherketone) of the following formula (2) is known from literature such as JP-A-52-38000, U.S. Pat. No. 3,953,400, etc., and Tg154
℃, Tm is a polymer with 365℃. (below,
(abbreviated as PEK) Furthermore, the poly(aryletherketone) of the following formula (3) is a polymer known from literature such as JP-A-60-240726 and US Pat. No. 4,398,020. (hereinafter referred to as PEKK) Furthermore, poly(aryletherketone) of the following formula (4) is also a known polymer from literature such as US Pat. No. 3,956,240. (hereinafter abbreviated as PEEKK) These poly(aryletherketones) are
As mentioned above, it has a well-balanced combination of various properties that are at the highest level among thermoplastic resins, and making it into fibers is of great industrial significance. Fiberization of these poly(aryletherketones) has been studied in various places, but it is historically new and there are no documents, and it is hard to say that the manufacturing technology is sufficiently established. Among them, PEEK fiberization research is quite advanced, and there are many documents (for example, ()
Publication No. 191322; () Res. Disclosure, April,
PP104 (1982); () Journal of the Japan Textile Society, Vol, 41, No.
1, 59 (1985), etc.), the only PEEK fibers currently on the market are monofilaments, and the mechanical properties of these monofilaments are still far from satisfactory. There are some documents (for example, Japanese Patent Publication No. 56-33419) regarding the fiberization of PEK (a polymer represented by the above formula (2)).
It is only seen in The basis of the poly(arylether) ketone fiberization method disclosed in the above-mentioned known literature, particularly the method of drawing melt-spun yarn, is to draw at a drawing temperature higher than the Tg of the polymer or spun yarn. This in itself is understood to be the general principle of conventionally known methods for drawing thermoplastic fiber-forming polymers. That is, according to these documents, stretching is
A method is used in which the heating is carried out in a heating medium at a temperature higher than Tg and lower than Tm, or in contact with a heating body at the above temperature. (c) Purpose of the Invention The present inventors have focused on the outstanding properties of various poly(aryletherketones) including PEEK, and have attempted to make them into fibers and have conducted various studies. When drawing at a drawing temperature higher than Tg, it is true that the tensile strength of the drawn yarn increases as the drawing temperature increases, but on the other hand, the tensile elongation rapidly decreases as the drawing temperature increases. The silk factor decreases, and at the same time, fuzz and flops occur frequently during stretching, making it difficult to obtain stable stretchability.
It was found that there were problems as an industrial manufacturing method. Therefore, an object of the present invention is to eliminate the drawbacks of conventionally known drawing methods and to produce poly(aryletherketone) fibers having balanced and satisfactory quality as industrial fibers in an industrially stable manner. The purpose is to provide a method. (d) Structure of the present invention That is, the present invention provides a spun yarn obtained by melt-spinning a poly(aryletherketone) consisting essentially of at least one type of repeating unit of the following formulas () to (). , the spun yarn is stretched at a temperature below Tg and above (Tg - 50°C), and if necessary, following the stretching, the spun yarn is
Poly(aryletherketone) characterized by heat treatment at a temperature higher than Tc and lower than Tm
It is a method of manufacturing fibers. In the above formula, Ar is independently a divalent aromatic group selected from phenylene, biphenylene or naphthalene, and X is independently O, or a direct bond, n is an integer from 0 to 3, b,
c, d and e are 0 or 1, a is an integer from 1 to 4, and preferably d is 0 when b is 1. Preferred poly(aryletherketones) include those having repeating units of the following formula. These poly(arylketones) are made by methods well known in the art. One such method involves heating a substantially equimolar mixture of at least one bisphenol and at least one dihalobenzoid compound or at least one halophenol compound as described in Canadian Patent No. 847,963. It becomes more. Preferred bisphenols in such a method include hydroquinone, 4,4-dihydroxybenzophenone, 4,4-dihydroxyphenyl, and 4,4-dihydroxydiphenyl ether. Preferred dihalo and dihalobenzoide compounds include 4-(4-chlorobenzoyl)phenol, 4,4-difluorobenzophenone, 4,4-dichlorobenzophenone, 4-chloro-4'-fluorobenzophenone, and can be mentioned. These poly(arylketones) can be made, for example, by methods such as those described in US Pat. No. 4,176,222. This method uses a substantially equimolar mixture of (1) at least one bisphenol and at least one dihalobenzoid compound, or (2) at least one halobenzoid compound, at a temperature range of 100°C to 400°C. In phenols (dihalobenzoid compounds or halophenols, the halogen atoms are in the ortho or para position to these atoms -CO
- group activated by the above-mentioned sodium carbonate or bicarbonate group) and a mixture of sodium carbonate or bicarbonate and a second alkali metal salt of carbonate or bicarbonate (activated by said second carbonate or bicarbonate group).
The alkali metal of the alkali metal salt has a higher atomic number than sodium, and the amount of the secondary alkali metal carbonate or bicarbonate salt is between 0.001 and 0.2 gram atom of the higher atomic number alkali metal present per gram atom of sodium. and the total amount of alkali metal carbonate or bicarbonate is such that at least one alkali metal is present for each phenol group present), followed by separation of the polymer from the alkali metal halide. It becomes more. Also, the formula: Poly(aryl ketones), such as those having repeating units of , can be prepared by the Friedel-Crafts reaction utilizing a hydrogen fluoride-boron trifluoride catalyst, as described, for example, in U.S. Pat. No. 3,953,400. Furthermore, the following formula: The poly(aryl ketone) of
3441538; 3442857 and 3516966 by a Friedel-Crafts reaction using a boron fluoride-hydrogen fluoride catalyst. These polyketones are listed in US Defense Bulletin No. T103703.
and US Pat. No. 4,396,755. In this method, reactants such as (a) an aromatic monocarboxylic acid, (b) a mixture of at least one aromatic dicarboxylic acid, and a combination of (a) and (b) are combined with a fluoroalkanesulfonic acid, particularly trifluoromethane. React in the presence of sulfonic acid. Furthermore, the following formula: or The poly(aryl ketone) of
It can also be produced by a method such as that described in No. 4398020. In such a method, (a) (1) formula YOC-Ar-COY (in the above formula, -Ar- is a divalent aromatic group,
Y is a halogen and COY is an acyl halide group bonded to an aromatic nucleus. at least one aromatic diacyl halide of (which is polymerizable with at least one aromatic compound of () below) of the formula H-Ar'-H (in the above formula, -Ar'- is is a divalent aromatic group,
And H is a hydrogen atom bonded to an aromatic nucleus. ) and at least one aromatic compound in substantially equimolar amounts. (b) Formula H-Ar''-COW (in the above formula, -Ar''- is a divalent aromatic group,
And H is a hydrogen atom bonded to an aromatic nucleus,
W is a halogen and COW is an acyl halide group bonded to an aromatic nucleus. ) and (c) a combination of (a) and (b) are reacted in the presence of a fluoroalkanesulfonic acid. As used herein, the term "poly(aryletherketone)" collectively refers to homopolymers, copolymers, terpolymers, graft polymers, and the like. For example, any two or more of repeating units () to () can be combined to form a copolymer or the like. Polymers suitable for fiber applications require a certain degree of polymerization, and polymers with an intrinsic viscosity (..) of 0.7 or more are preferred. here. ．． is concentrated sulfuric acid 100
The intrinsic viscosity is calculated by dissolving 0.1g of polymer per cc and measuring at 25°C. It goes without saying that the above polymer may contain various additives to improve its stability, color tone, physical properties, adhesive properties, etc. Next, a method for producing poly(aryletherketone) fiber will be described in detail. When melt spinning poly(aryletherketone) polymer,
The polymer is supplied to a melt extrusion device that can raise the temperature to approximately 500℃, and the final temperature is 30 to 70 degrees below its melting point (Tm).
℃ higher temperature, i.e. (Tm + 30℃) ~ (Tm + 70℃)
After completely melting the spinning material, use a spinneret normally used as a melt spinning nozzle or a special spinning nozzle having a needle-like object in the discharge hole as described in JP-A No. 60-259619, which was previously proposed by the present inventors. It is spun through a spinning pack equipped with a spinneret and the like. The spun yarn is wound up using a conventionally known cooling and winding method. That is, when spinning a thick denier yarn with a spun yarn (undrawn yarn) having a single yarn denier of about 1000 de or more,
After the spun yarn is cooled and solidified in a hot water bath with a liquid temperature of 40 to 95°C provided directly below the spinneret, an ethylene glycol bath, a silicone oil bath, etc., it is wound up using a torque winder or the like. On the other hand, the single yarn denier of spun yarn (undrawn yarn) is approximately
When spinning fine denier yarn of 1000 de or less,
After spinning, it is cooled and solidified in the air, then oiled and wound up. The poly(aryletherketone) used in the present invention is a high melting point, high viscosity polymer, and since it rapidly solidifies by cooling after spinning, especially in the case of a fine denier, it is usually used in melt spinning of high viscosity polymers. By providing a heating cylinder (hood) for slowly cooling the spun yarn directly under the spinneret, it is possible to impart stringiness at higher speeds. Furthermore, if the air entanglement treatment is performed immediately before taking off the spinning yarn, the subsequent handling properties such as stretchability will be improved. Poly(aryletherketone) is a high-melting point, high-viscosity polymer, but the amount of gel-like substances that are generated and mixed in during the polymerization process and high-temperature melting process during spinning is larger than that of ordinary low-melting point polymers. ,
In particular, when spinning fine denier filaments, the influence of gel-like substances is at a level that cannot be ignored. The adverse effects of gel-like substances can be improved by a combination of reinforcement and the cap described in JP-A-60-259619. The thus obtained spun yarn (undrawn yarn) is then subjected to stretching, and a conventionally known stretching device can be used as the stretching device. That is, one or more stages of heating and multi-stage stretching are carried out using a non-contact type or contact type heater using heated steam, a heating medium electric heater, etc., and heat treatment is performed under tension or without tension as required. Now, poly(aryletherketone) fiber,
For example, for drawing PEEK undrawn yarn, as described above, drawing at a drawing temperature higher than Tg has been conventionally employed, as with fibers made of general thermoplastic fiber-forming polymers. The present inventors initially considered drawing poly(aryletherketone) fibers in accordance with this conventional basic common sense, but as mentioned above, they found that there were the following problems. That is, as the stretching temperature becomes higher than Tg,
The tensile elongation of the drawn yarn decreases, and the silk factor decreases. b. As a result, fuzz and wraps occur frequently during stretching,
Stable stretching is not possible. In order to solve the above-mentioned problems, the present inventors searched for the optimal conditions for stretching temperature and found that, contrary to conventional wisdom and theory, "stretching at a temperature below Tg" is effective. This result means that the conventional drawing theory of synthetic fibers, that is, the concept of "drawing at a temperature higher than Tg" is not necessarily universal. The exact reason why drawing at temperatures higher than Tg is undesirable for poly(aryletherketone) fibers has not been fully elucidated, but the answer lies in the thermal properties of poly(aryletherketone). It seems that there are. The results of differential thermal analysis (DTA^; heating rate 10°C/min) of samples with mostly amorphous parts, such as poly(aryletherketone) quenched polymer and poly(aryletherketone) undrawn yarn, are shown below. Shown in Figure 1. Figure 1 shows the DTA curve of PEEK, which shows a small endothermic peak (Tg) indicating a glass transition at around 145-150°C from the low temperature side, and a small endothermic peak (Tg) showing a glass transition at around 160-170°C very close to this. A large exothermic peak (Tc) indicating oxidation and 340-345℃
There is an endothermic peak (Tm) nearby that indicates melting. Unlike other common polymers, PEEK has a Tg
It can be seen from Figure 1 that and Tc are extremely close to each other. Therefore, when drawing PEEK undrawn yarn at a temperature above Tg, especially when drawing at a temperature considerably higher than Tg, oriented drawing is performed while crystallization occurs in parallel, resulting in low elongation, fluff, and It is surmised that this is connected to the occurrence of the rupture. The thermal properties of poly(aryletherketones) such as PEEK are similar to those of PEEK, that is, Tg and Tc tend to be close to each other (for example, PEK has a Tg of approximately 154°C). , Tc approx. 169℃
According to the present invention, as a method for producing fibers with high silk factor and good drawability, Tg ~ (Tg
-50℃), preferably (Tg-10℃) to (Tg-50
Suppress crystallization at temperatures as low as 1.5 °C), e.g.
It is sufficiently oriented and stretched at a drawing ratio of ~2.5 times, and then as necessary (for example, when obtaining high strength, low heat shrinkage yarn), Tc ~ Tm, preferably Tc ~
It is appropriate to carry out crystallization by heat treatment at a temperature of (Tm - 30°C) under tension or in a relaxed state. Note that the drawing temperature and heat treatment temperature in the present invention both refer to the temperature of the yarn during drawing or heat treatment, and the yarn temperature immediately after the drawing and heat treatment heater was measured using a yarn thermometer manufactured by Transmet Corporation in the United States. It does not refer to the temperature of the heating medium. The method of the invention is preferably applicable to multifilaments and monofilaments. In addition, it is possible to take one or more spindles for both multifilament and monofilament, and a spin-draw method in which drawing is directly connected to spinning may be adopted. The drawn yarn or drawn/heat-treated yarn obtained by the method of the present invention can be treated with a finishing oil or other treatment agent to improve handling in post-processing such as weaving or knitting, or depending on the intended use. Air entanglement treatment can also be performed if necessary. (e) Effects of the Invention According to the method of the present invention, high toughness fibers that can be used as industrial fibers can be produced over a wide range from multifilaments with a single filament denier of several deniers to monofilaments with a diameter of about 1 mm. It is possible to stably produce poly(aryletherketone), and it can maximize the inherent excellent properties (heat resistance, chemical resistance, radiation resistance, hydrolysis resistance, etc.) of poly(aryletherketone). This is an industrially extremely useful method that can provide fibers. Poly(aryletherketone) fibers including PEEK obtained by the method of the present invention can be widely used as industrial fibers, for example, as monofilaments, heat-resistant and abrasion-resistant brushes,
Heat-resistant, heat-resistant water weight cloth joint core materials for dryer canvases, abrasion-resistant, high-elastic guts, etc. Multifilaments include heat-resistant, chemical-resistant filters and packings, radiation-resistant filters and packings, as well as glass fibers, carbon fibers, It is useful for resin matrices for composite materials with inorganic fibers such as ceramic fibers and metal fibers, and high strength and high elasticity organic fibers such as aromatic polyamide fibers and heterocyclic polymer fibers. (F) Examples The present invention will be further explained in detail with reference to Examples, but the following Examples are intended to specifically illustrate the present invention, and are not intended to limit the scope of the present invention in any way. isn't it. Example 1 PEEK resin (ICI) with an intrinsic viscosity (..) of 0.96
After melting VICTREX) at 400℃, the diameter is 0.45.
Using a normal spinneret with a diameter of 1.35 mm, a length of 1.35 mm, and 60 holes, the yarn is spun at a spinneret temperature of 380°C, and then passed through a heating tube with a length of 30 cm and a surface temperature of 280°C installed directly below the spinneret.
After air cooling, refuel and wind at a speed of 150 m/min.
A PEEK spun yarn (undrawn yarn) of 800 de/60 fils was obtained. The result of differential thermal analysis (DTA: temperature increase rate 10°C/min) of this spun yarn (undrawn yarn) was Tg = 149
℃, Tc=159℃, Tm=340. Using this spun yarn, drawing and heat treatment conditions were investigated. That is, the spun yarn (undrawn yarn) is supplied to a heating supply roller, and the stretching ratio is adjusted between the next room temperature stretching rollers.
2.0 to 2.25 at a stretching speed of 200 m/min, then heat treated with a hot plate heater and wound up via a take-up roller. Table 1 shows the results of examining the properties and stretchability of drawn yarns or drawn heat-treated yarns using the above-mentioned drawing equipment and varying the drawing temperature and heat treatment temperature. Here, the words and symbols used in Table 1 will be briefly described. (a) Silk factor: (Tensile strength (g/de)) ×
√ (expressed as tensile elongation (%). This value is a guideline for the mechanical properties of the fiber. (b) Dry heat shrinkage rate: Shrinkage rate (%) measured under no load at 180℃ for 30 minutes (c ) Differential thermal properties: DTA results, Tg or Tc
× indicates that a considerable amount of peak remains, △ indicates that a small amount of peak remains, ○ indicates that there is no peak at all.
This is used as a guideline for the heat setting properties of drawn yarn. (d) Stretchability: ○ indicates that no fluff or flops appear during 30 minutes of stretching, △ indicates that some fuzz or flops occur, and × indicates that they occur frequently and are difficult to stretch.

【table】

[Table] (Note) Experiment numbers marked with * indicate comparative examples.
In Table-1, experiments No. 1 to 21 had a stretching ratio of 2.0;
Nos. 22 to 26 were tested for stretchability and heat setability at a draw ratio of 2.25. As can be seen from Table 1, when stretched at a temperature higher than Tg (160°C or higher in this example),
As the stretching temperature increases, the tensile strength generally increases little by little, but on the other hand, the tensile strength decreases, the silk factor tends to decrease, and due to the lower elongation, fuzz and lapping occur. Stretchability deteriorates. In particular, when the stretching speed reached 190°C, the slack of the yarn on the heated supply roller (due to self-stretching) was added, resulting in extremely poor stretching properties (Experiment No.
5, 10, 15, 21, 26). When the stretching temperature is below Tg, the stretchability is good and the silk factor is above the desired level. However, those whose heat treatment temperature is Tc or lower (150℃ or lower in this example) (Experiments No. 1 to 3, No. 6 to 8)
As the heat setting is insufficient and the dry heat shrinkage rate is high, it is still recommended as a general industrial fiber.
It is preferable to perform sufficient heat treatment at a temperature higher than Tc so that the tensile strength silk factor is high and the dry heat shrinkage rate is low. Example 2 After melting the same PEEK resin as Example 1 at 400℃,
Using a regular monofilament spinneret with a diameter of 4 mm, a length of 8 mm, and one hole, the spinneret temperature was 375.
Spun at 50°C and then cooled in a 50°C hot water bath to increase speed
It was wound up at 20 m/min to obtain an undrawn monofilament of 15,300 de. The results of differential thermal analysis of this undrawn monofilament were Tg = 146°C, Tc = 167°C, and Tm = 342°C. A non-contact heating heater (for stretching) is provided between the supply roller (room temperature) and the drawing roller (room temperature) for this undrawn monofilament, and another non-contact heating heater is provided between the drawing roller and the take-up roller (room temperature). (for heat treatment) with a stretching ratio of 3.4,
Stretching and heat treatment were performed at a stretching speed of 20 m/min.
In this equipment, the stretching temperature is 140℃ and the heat treatment temperature is 250℃.
The atmospheric temperature of each heater was controlled so that The resulting PEEK monofilament has a thread diameter of 0.7
mm, tensile strength 5.8 g/de, tensile elongation 18%, and dry heat shrinkage rate 6.1%. As a comparative example, a monofilament obtained in the same manner as above except that the drawing temperature was changed to 180°C has a tensile strength of 5.7 g/de, but a low tensile elongation of 8% and a low silk fabric. It was hot. Example 3 PEK (repeating unit melted at 425℃, diameter 0.6mm, length 1.8mm, number of holes.
Spinneret temperature 410 using 36 ordinary spinnerets
℃, the surface temperature is 305℃, and the surface temperature is 305℃, and it is air-cooled through a 30cm-long heating cylinder, then oiled and wound at a speed of 150m/min. ) was obtained. This undrawn yarn has Tg=
It had thermal properties of 161°C, Tc = 178°C, and Tm = 370°C. This undrawn yarn was drawn using the same drawing equipment as in Example 1 at a drawing ratio of 1.9, a drawing speed of 100 m/min, and a drawing temperature of 150°C.
The fiber obtained by drawing heat treatment at 250℃ has a tensile strength of 402 de/36 fils, a tensile strength of 5.5 g/de, and a tensile elongation.
It has good physical properties of 22% and dry heat shrinkage rate of 5.6.
Moreover, there were no particular problems with stretchability.

[Brief explanation of drawings]

Figure 1 shows differential thermal analysis (DTA) of PEEK undrawn yarn.
FIG. 1 is a schematic diagram showing the results. Tg: glass transition peak, Tc: crystallization peak,
Tm: melting peak.

Claims (1)

[Scope of Claims] 1 A spun yarn obtained by melt-spinning a poly(aryletherketone) consisting essentially of at least one repeating unit of the following formulas () to (),
Below the glass transition point (Tg) of the spun yarn, (Tg-50
℃) or higher, and if necessary, subsequent to the stretching, the poly(aryl ether) is heat-treated at a temperature higher than the crystallization temperature (Tc) and lower than the melting point (Tm) of the spun yarn. Ketone) fiber manufacturing method. (However, the glass transition point (Tg), crystallization temperature (Tc), and melting point (Tm) each indicate the peak temperature of glass transition, crystallization, and melting in differential analysis.) [In the above formula, Ar is independently a divalent aromatic group selected from phenylene, biphenylene or naphthalene, and X is independently O, or a direct bond, n is an integer from 0 to 3, b, c, d and e are 0 or 1, and a
is an integer from 1 to 4. ] 2 Poly(aryletherketone) has the following formula: The manufacturing method according to claim 1, wherein the manufacturing method has a repeating unit of. 3 Poly(aryletherketone) has the following formula: The manufacturing method according to claim 1, wherein the manufacturing method has a repeating unit of. 4 Poly(aryletherketone) has the following formula: The manufacturing method according to claim 1, wherein the manufacturing method has a repeating unit of. 5 Poly(aryletherketone) has the following formula: The manufacturing method according to claim 1, wherein the manufacturing method has a repeating unit of. 6. The manufacturing method according to claim 1 or 2, wherein the stretching temperature is within the range of (Tg - 10°C) to (Tg - 50°C).