JP2007009370A - Method for producing blend type conjugate fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a blend type conjugate fiber in which rapid raise of melting viscosity is suppressed and yarn-making property is improved and feed of a product which is stable over a long time is made possible by suppressing reaction of a melted liquid crystal-forming polyester (A) with a polyphenylene sulfide (B). <P>SOLUTION: In the production method of a blend type conjugate fiber composed of the melted liquid crystal-forming polyester (A) and the polyphenylene sulfide (B), an aromatic dicarboxylic acid monomer and/or its esterified derivative is added to a mixing system of these polymers (A) and (B) and then, melt-spinning is carried out. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for producing a blend type composite fiber having high strength and high elastic modulus and excellent in wear resistance, fatigue resistance and chemical resistance, and the composite fiber obtained by the present invention includes: It is widely used for general industrial materials, especially ropes, rubber reinforcement, geotextiles, FRP applications, computer ribbons, printed circuit board fabrics, air bags, bag filters, fishery materials such as fishing nets, screen rods, etc.

  It is known that fibers obtained by melt spinning a melt liquid crystal forming polyester are excellent in high strength, high elastic modulus, dimensional stability, and the like.

  Molten liquid crystal forming polyester fiber has high strength and high elastic modulus due to the highly oriented molecular chain in the fiber axis direction, but only weak intermolecular force works in the direction perpendicular to the fiber axis. Therefore, it is easy to be fibrillated by friction, and the occurrence of this fibril has caused troubles such as fiber strength being lowered and being damaged. Further, kink bands due to buckling tend to occur, and since they tend to localize, they have drawbacks such as poor wear resistance.

  Therefore, blend type composite fibers (see Patent Documents 1, 2, and 3) composed of a melt liquid crystal-forming polyester and other polymers have been proposed as fibers in which these defects are improved.

  Thus, the processability of LCP is improved by using a composite fiber composed of a molten liquid crystal forming polyester and another polymer. In particular, when polyphenylene sulfide is used as another polymer, the abrasion resistance is improved, the appropriate spinning temperature is approximated, and characteristics such as chemical resistance can be further imparted. is there.

  However, melted liquid crystal forming polyester blended with polyphenylene sulfide has a large increase in viscosity in the melted state, and when heated for a long time at an abnormal residence part or the like, the melt viscosity becomes high, resulting in foreign matter, which deteriorates the yarn-making property. There is a problem that the loss of raw materials increases when trying to obtain a homogeneous product because it takes a long time until the melt viscosity gradually increases and stabilizes from the start of spinning.

  When the melted liquid crystal-forming polyester is subjected to thermal processing after forming a polymer, the end groups react with each other and the polymer chain tends to continue to grow, and the melt viscosity increases as the polymer chain grows.

  As a method for solving such a problem, an excess aromatic dicarboxylic acid monomer and / or an esterified derivative thereof is added at the time of polymerization, and the polymer chain end of the molten liquid crystal forming polyester is substantially substituted with a carboxylic acid end group and / or A method for producing the esterified derivative has been proposed (see Patent Document 4).

However, even when a molten liquid crystalline polyester having a terminal modified by the above method is used, the increase in viscosity in the state of melt blending with polyphenylene sulfide cannot be suppressed. In other words, the increase in melt viscosity when heated for a long time in a melt-blended state with polyphenylene sulfide cannot be solved by simply modifying the melt-forming liquid crystal forming polyester alone, and avoid changes in physical properties and deterioration of yarn-making properties over time. I couldn't.
JP-A-11-293522 (second page) JP 2000-119952 A (page 3) Japanese Patent Laying-Open No. 2003-239137 (FIG. 1 on page 6) JP 60-40127 A (page 6)

  Regarding the cause of this problem, a mixed polymer of molten liquid crystal forming polyester (A) and polyphenylene sulfide (B) is heat-treated in a molten state, and S ( As a result of comparing the sulfur content, it can be seen that the S content is greatly increased by the heat treatment, and the molten polymer-forming polyester (A) and the polyphenylene sulfide (B) are obtained by heat-treating the mixed polymer. It is presumed that there is some reaction.

  Furthermore, the product and product gas resulting from the thermal decomposition of polyphenylene sulfide (B) act as a catalyst, and it is considered that when both polymers are mixed, the increase in melt viscosity becomes significant. This is because the melting temperature is increased. It can be inferred from the fact that the increase in melt viscosity is further promoted. For example, when an acidic gas is generated as the generated gas, it may act as a polymerization catalyst for the molten liquid crystal forming polyester (A).

  In the present invention, for this problem, by suppressing the reaction between the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B), the rapid increase in melt viscosity is suppressed, and the yarn-making property is improved. It is possible to provide a stable product supply.

  The present invention relates to a method for producing a composite fiber composed of a melt liquid crystal forming polyester (A) and a polyphenylene sulfide (B), wherein an aromatic dicarboxylic acid monomer and / or an esterified derivative thereof is added and then melt-spun. It is the manufacturing method of the blend type composite fiber characterized.

  ADVANTAGE OF THE INVENTION According to this invention, the blend type composite fiber which has high intensity | strength and a high elasticity modulus, and was excellent also in abrasion resistance and chemical-resistance can be manufactured stably for a long time.

  The molten liquid crystal forming polyester (A) used in the present invention refers to a polymer that exhibits optical anisotropy when heated and melted. This characteristic can be recognized by, for example, heating a sample made of molten liquid crystal forming polyester (A) on a hot stage and heating it under a nitrogen atmosphere, and observing the transmitted light of the sample under polarized light. When the sample is forced to flow, the amount of transmitted light changes, but this type of sample exhibits optical anisotropy even if it is stationary. In contrast, common polymers that do not exhibit optical anisotropy are essentially isotropic, with virtually no light transmission upon inspection in a stationary state.

  A conventionally well-known method can be used for the polymerization prescription of molten liquid crystal forming polyester (A) used for this invention.

  Examples of the melt liquid crystal forming polyester (A) used in the present invention include a. A polymer of aromatic oxycarboxylic acid, b. Polymer of aromatic dicarboxylic acid and aromatic diol, aliphatic diol, c. and a copolymer of a and b.

  Where: a. Examples of the aromatic oxycarboxylic acid include hydroxybenzoic acid and hydroxynaphthoic acid, and alkyl, alkoxy and halogen substituted products of the above aromatic oxycarboxylic acid.

  B. Aromatic dicarboxylic acids include terephthalic acid, isophthalic acid, diphenyldicarboxylic acid, naphthalenedicarboxylic acid, diphenylether dicarboxylic acid, diphenoxyethanedicarboxylic acid, diphenylethanedicarboxylic acid, etc., or alkyl, alkoxy, halogen substituted products of the above aromatic dicarboxylic acids Etc.

  And b. Examples of the aromatic diol include hydroquinone, resorcin, dioxydiphenyl, naphthalenediol, and the above aromatic alkyl, alkoxy, and halogen-substituted products. Examples of the aliphatic diol include ethylene glycol, propylene glycol, butanediol, neodymium, and the like. Examples include pentyl glycol.

  Preferable examples of the molten liquid crystal forming polyester (A) used in the present invention include a copolymer of a p-hydroxybenzoic acid component and an ethylene terephthalate component, a p-hydroxybenzoic acid component and 4,4′-dihydroxybiphenyl. And terephthalic acid or isophthalic acid are copolymerized, p-hydroxybenzoic acid component and 6-hydroxy 2-naphthoic acid component are copolymerized, p-hydroxybenzoic acid component and 6-hydroxy 2-naphthoic acid Examples include those obtained by copolymerizing an acid component, hydroquinone and terephthalic acid.

  The melting point (hereinafter referred to as MP) of the molten liquid crystal forming polyester (A) used in the present invention is preferably in the range of 220 to 380 ° C., more preferably so as not to cause processing problems in spinning, solid phase polymerization and the like. MP is 250-350 degreeC.

  The present invention provides a blend type composite fiber that exhibits the high strength and high elastic modulus of the molten liquid crystal forming polyester (A) and has excellent dimensional stability by using the molten liquid crystal forming polyester (A) as one component. Can be provided.

  The present invention is characterized in that polyphenylene sulfide (B) is used as a composite target polymer of molten liquid crystal forming polyester (A). Polyphenylene sulfide (B) has a melting point of molten liquid crystal forming polyester (A). Because of its close heat resistance and excellent heat resistance, it is difficult to be thermally deteriorated even at the spinning temperature of the melted liquid crystal forming polyester (A) and stable spinning is possible. In addition, when heat-treating the obtained fiber, it is necessary to perform treatment at a temperature in the vicinity of the melting point of the melted liquid crystal-forming polyester (A). In addition, it is difficult to fuse between fibers, and a fiber excellent in handleability in a weaving process or the like can be obtained.

  The polyphenylene sulfide (B) has a branched or linear form, and the present invention is effective when any form of the polyphenylene sulfide (B) is used. It is preferable to use linear polyphenylene sulfide (B) in order to obtain good spinning properties and to obtain better physical properties such as chemical resistance, mechanical properties, and fibrillation resistance.

  Furthermore, although it varies depending on the polymerization conditions, polyphenylene sulfide (B) generally contains metals such as Na, Ca, Mg and Fe, and the terminal of the polymer chain is the terminal derived from the polymerization raw material and the catalyst in addition to these metals. Group, for example, when p-dichlorobenzene is used as a polymerization raw material, it becomes a Cl group, and when N-methylpyrrolidone is used as a polymerization catalyst, it becomes an N-alkylpyridine group or a pyridine group which is a decomposition product thereof. Yes. The present invention is effective when polyphenylene sulfide (B) having any terminal is used, but enhances the adhesiveness of the composite interface with molten liquid crystal forming polyester (A), and suppresses the interfacial peeling of sea-island components. From the point that the effect is obtained, after polymerizing the polyphenylene sulfide (B) having these polymer chain ends, the polymer is acid washed with an inorganic acid such as hydrochloric acid, an organic acid such as acetic acid, etc. It is preferable to use terminal polyphenylene sulfide (B).

  The molten liquid crystal-forming polyester (A) and polyphenylene sulfide (B) used in the present invention may be blended with other polymers as long as the effects of the present invention are not impaired. Other polymers include, for example, polyethylene terephthalate, polytetramethylene terephthalate, polytrimethylene terephthalate, poly-1,4-cyclohexanedimethylene terephthalate, polyester such as polycaprolactone, or copolymers thereof, polyethylene, polypropylene, polystyrene. , Polyolefins such as polymethyl methacrylate, or copolymers thereof, polyamides such as nylon 6, nylon 66, nylon 46, nylon 6T, nylon 9T, or copolymers thereof, polyethylene glycol, polypropylene glycol, polytetramethylene glycol And polyether such as polycarbonate, polyether imide, polyketone, and polysulfone.

  The molten liquid crystal-forming polyester (A) and polyphenylene sulfide (B) used in the present invention include various metal oxides, kaolin, silica and other inorganic substances, colorants, matte, and the like within the range not impairing the effects of the present invention. A small amount of additives such as an agent, a flame retardant, an antioxidant, an ultraviolet absorber, an infrared absorber, a crystal nucleating agent, and a fluorescent brightening agent may be contained.

  The present invention is characterized by adding an aromatic dicarboxylic acid monomer and / or an esterified derivative thereof when melt-spun the melt liquid crystal forming polyester (A) and the polyphenylene sulfide (B). By adding, even if it heats for a long time in the state which mixed both polymers, a raise of melt viscosity is not seen, but the physical-property change and deterioration of a spinning property over time can be improved. This suppresses the growth of the polymer chain of the molten liquid crystal forming polyester (A) itself during spinning and suppresses the reaction between the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B). This seems to be because the rapid increase in melt viscosity generated by mixing the slag could be suppressed. When we separated the molten liquid crystal-forming polyester (A) in the sample heat-treated with both polymers mixed in a model, and measured the S (sulfur) component content, it increased significantly compared to before heating. It is considered that the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B) have undergone some reaction by the heat treatment. Further, the thermal decomposition product of polyphenylene sulfide (B), particularly an acidic gas, causes an increase in melt viscosity as a catalyst, and these are considered to be a complex factor in increasing the melt viscosity.

  In the present invention, the aromatic dicarboxylic acid monomer and / or the esterified derivative thereof not only reacts with the terminal of the molten liquid crystal forming polyester (A) but also heat that is likely to occur in the presence of polyphenylene sulfide (B). It seems that it reacts quickly with the ester bond cleavage site generated by decomposition and suppresses the generation of branched chains due to the bond with polyphenylene sulfide (B), thereby suppressing the increase in melt viscosity of this mixed polymer. .

  Among the aromatic dicarboxylic acid monomers and / or esterified derivatives thereof used as additives in the present invention, aromatic dicarboxylic acid monomers include terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid. 1,4-naphthalenedicarboxylic acid, 2-phenylterephthalic acid, 4,4′-biphenyldicarboxylic acid, methylterephthalic acid, methylisophthalic acid, diphenylether-4,4′-dicarboxylic acid, diphenylsulfone-4,4′- Examples thereof include dicarboxylic acid, diphenyl ketone-4,4′-dicarboxylic acid, 2,2′-diphenylpropane-4,4′-dicarboxylic acid and the like.

  An ester derivative of an aromatic dicarboxylic acid is an ester compound obtained from an aromatic dicarboxylic acid and a monovalent or polyhydric alcohol as shown above. Examples of the monohydric alcohol include methanol, ethanol, 1-propanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, s-butyl alcohol, t-butyl alcohol, pentanol, neopentyl alcohol, hexanol, heptanol, Examples include saturated or unsaturated aliphatic monohydric alcohols such as octanol, alicyclic monohydric alcohols such as cyclohexanol, and aromatic monohydric alcohols such as benzyl alcohol. Examples of the polyhydric alcohol include ethylene glycol, 1,3-propanediol, propylene glycol, neopentyl glycol (2,2-dimethyl-1,3-propanediol), 1,4-butanediol, and 1,5-pentane. In addition to aliphatic diols such as diol and 1,6-hexanediol, cycloaliphatic polyhydric alcohols such as cyclohexanediol and cyclohexanedimethanol, ethylene oxide adducts of bisphenol A, glycerin, pentaerythritol, dipentaerythritol, etc. , 3-bis (2-hydroxyethoxy) benzene, 1,4-bis (2-hydroxyethoxy) benzene, aromatic polyhydric alcohols such as aromatic diols such as bis (4-β-hydroxyethoxyphenyl) sulfone, diethylene glycol Dihydric alcohols such as alkylene glycols such as triethylene glycol, tetraethylene glycol and dipropylene glycol, trihydric alcohols such as glycerin, trimethylolethane, trimethylolpropane and trimethylolmethane, and tetrahydric alcohols such as pentaerythritol. Can be mentioned.

  The aromatic dicarboxylic acid monomer and / or esterified derivative thereof may be used alone or in combination of two or more. Among these, terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid are preferable from the viewpoint of availability.

  The number average molecular weight Mn of the aromatic dicarboxylic acid monomer and / or esterified derivative thereof is preferably 1000 or less. By being 1000 or less, it can disperse | distribute uniformly in a fiber and can suppress a viscosity raise effectively and can improve a yarn-making property. The number average molecular weight Mn of the aromatic dicarboxylic acid monomer and / or esterified derivative thereof is more preferably 100 or more and 400 or less. For example, the molecular weight of a solute and its content can be determined by incorporating an ultraviolet / visible absorption detector into the GPC device and measuring the ultraviolet / visible absorption intensity of the size-sorted molecular chain solution with elution time. It is obtained by calculating sequentially.

  Preferred examples of the aromatic dicarboxylic acid monomer and / or esterified derivative thereof used as the additive of the present invention include terephthalic acid and dimethyl terephthalate and diphenyl terephthalate which are esterified derivatives of terephthalic acid.

  More preferably in the present invention, terephthalic acid is used as it is without esterification. When terephthalic acid is used as an additive, the effect of the present invention appears more remarkably.

  In the present invention, the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B) may be mixed either in a solid state or in a molten state, and the shape of each polymer is preferably a chip shape. However, it may be powder or flakes. Further, the melted liquid crystal forming polyester (A) and the polyphenylene sulfide (B), and the aromatic dicarboxylic acid monomer and / or the esterified derivative thereof may be mixed at the same time. One component may be mixed.

  Moreover, either a method of performing mixing and spinning by a kneading machine in different steps, or a method of performing mixing and spinning in one step using a spinning machine directly equipped with a kneading machine may be used. As a specific method, for example, a three-component mixed polymer is prepared by mixing three components with a kneader, and then the polymer is melt-spun, and a molten liquid crystal forming polyester (A) and a polyphenylene sulfide (B) are mixed. A method of adding an aromatic dicarboxylic acid monomer and / or an esterified derivative thereof when melt-spinning the polymer after preparing a two-component mixed polymer mixed in a kneader, and using a spinning machine directly equipped with a kneader For example, a method in which the three components are mixed and added simultaneously in a solid state and then spun as it is.

  In the present invention, the time for which the polymer is in a molten state may be such that the additive can react. From the viewpoint of general melt spinning, it is preferable that the time in the molten state is short. A method in which a spinning machine provided directly is used in one step is preferable.

  Examples of the kneader used for mixing include a single-screw kneader, a twin-screw kneader, and various kneaders, and a biaxial kneader is preferable from the viewpoint of kneadability. Further, in order to keep the fiber quality uniform, it is preferable to adopt a screw configuration that reduces the decrease in viscosity and abnormal retention due to thermal degradation and hydrolysis of the polymer.

  The aromatic dicarboxylic acid monomer and / or esterified derivative thereof used as an additive of the present invention is 0.1% by weight of the total weight of the dried molten liquid crystal forming polyester (A) and polyphenylene sulfide (B): 100 parts by weight of WA + WB. It is preferable to add 2 to 3.0 parts by weight.

  By making the addition amount 0.2 parts by weight or more, the effect of suppressing the increase in melt viscosity becomes sufficient, and the effect of improving the yarn-making property becomes clear. On the other hand, by using 3.0 parts by weight or less, for example, when terephthalic acid is used, terephthalic acid that cannot be completely dissolved cannot pass through the filtration filter of the spinning pack and is deposited on the filter, causing an increase in filtration pressure. The possibility of occurrence of such a problem is reduced, and a polymer chain end which is a reaction site of solid-phase polymerization of the molten liquid crystal-forming polyester (A) can be secured, so that the strength of the obtained fiber becomes sufficient.

  As a range in which these effects can be sufficiently exerted, the addition amount of the aromatic dicarboxylic acid monomer and / or esterified derivative thereof is more preferably 0.5 to 2.0 parts by weight.

  The blend type composite fiber obtained by the present invention has a sea-island structure composed of a melt liquid crystal-forming polyester (A) and a polyphenylene sulfide (B), and has a branching state as a dispersed state of island components. Alternatively, a portion where the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B) form a co-continuous phase may be included.

  Regarding the sea-island structure, the characteristics of both polymers such as the high strength and high elastic modulus characteristic of the molten liquid crystal forming polyester (A) and the chemical resistance characteristic of the polyphenylene sulfide (B) can be expressed simultaneously. From the above, it is preferable to have a sea-island structure in which the molten liquid-crystal forming polyester (A) is an island component and the polyphenylene sulfide (B) is a sea component. (A) is substantially covered with polyphenylene sulfide (B), and good wear resistance can be obtained.

  In the present invention, the combined weight ratio of the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B) is the weight of the molten liquid crystal forming polyester (A) is WA and the weight of the polyphenylene sulfide (B) is WB. It is a value represented by WA / WB at the time, and is a ratio when both polymers are weighed in terms of weight in a solid state or a molten state.

  In the present invention, it is preferable that WA / WB is larger than 1, that is, the weight of the molten liquid crystal-forming polyester (A) is larger than the weight of the polyphenylene sulfide (B), thereby having excellent wear resistance. Sufficiently high strength and high elastic modulus that can be applied to various industrial uses can be obtained.

  Furthermore, in order to obtain high strength and high elastic modulus and good wear resistance, WA / WB is more preferably 1.2 or more and 3.0 or less.

  In the cross section of the blend type composite fiber in which the island component obtained by the present invention is a melt liquid crystal forming polyester (A) and the sea component is polyphenylene sulfide (B), the fiber diameter is (R) and the island component diameter is (r). , It is preferable in terms of wear resistance that all island components satisfy r / R ≦ 0.3 and are dispersed throughout the fiber cross section. Here, the fiber diameter (R) is the diameter of the circumscribed circle of the fiber, and the island component diameter (r) is the diameter of the circumscribed circle of the island component. Here, in order to suppress the interfacial peeling between the sea component and the island component, it is more preferable that all the island components satisfy r / R ≦ 0.2. Moreover, since both polymers do not compatibilize, it is preferable that all island components satisfy r / R ≧ 0.00001, and more preferably satisfy r / R ≧ 0.00005.

  The present invention can also be produced using a known single-component spinning die, and the cross-section of the obtained fiber can be any shape such as a round shape or various irregular shapes.

  In the present invention, when melt spinning the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B), the spinning temperature is preferably 280 to 340 ° C. Since the reaction between the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B) is accelerated in proportion to the temperature, the spinning temperature is more preferably 320 ° C. or less from the viewpoint of suppressing this reaction.

  The blend type composite fiber obtained by the present invention already has sufficient strength and elastic modulus just by spinning. However, the blend type composite fiber is improved in the degree of polymerization by relaxation heat treatment or constant length heat treatment to further improve the strength and elastic modulus. A phase polymerization process can be performed.

  In this case, the treatment can be carried out under any condition such as in an inert gas atmosphere such as nitrogen, an active gas atmosphere containing oxygen such as air, or under reduced pressure or in vacuum. The heat treatment atmosphere is preferably a low-humidity gas having a dew point of −40 ° C. or less. The heat treatment condition is preferably performed in a temperature pattern in which the temperature is gradually increased from a temperature of 40 ° C. or lower from the melting point to a temperature not exceeding the melting point, based on the melting point of the melt-forming liquid crystal-forming polyester (A). Can be any temperature as long as it is 40 ° C. or less from the melting point. At this time, in order to prevent fusion between single fibers, it is preferable to treat the final treatment temperature at a melting point of about 5 ° C. or less. Furthermore, the processing time is several minutes to several tens of hours depending on the target performance. When the treatment temperature is about 5 ° C. or lower and the treatment temperature is about several tens of hours, the melting point of the melt-forming liquid crystal forming polyester may be improved, and this enables treatment at a higher temperature.

  In the heat treatment, various additives may be added in order to promote solid-state polymerization of the molten liquid crystal forming polyester (A).

  Supply of heat during heat treatment is a method using a medium such as liquid and gas, a method using radiation by a heating plate, an infrared heater, etc., a method of making contact with a heat roller, a heat plate, etc., an internal using a high frequency, etc. A heating method or the like can be used. The heat treatment is performed under tension or non-tension depending on the purpose, and the heat treatment is performed in the form of a drum, casserole, tow (for example, on a metal net) or continuously as a yarn between rollers. It is also possible to do. Furthermore, the form of the fiber can be either filament or cut fiber, and can be heat-treated after forming a fiber molded body such as a fabric or woven or knitted fabric.

  The blend type composite fiber obtained by the present invention has a high strength and a high elastic modulus which are the characteristics of the melt liquid crystal forming polyester (A), and the tensile strength of the fiber is preferably 12 cN / dtex or more. More preferably, it is 14 cN / dtex or more.

  In addition, in order to ensure sufficient dimensional stability and durability of the product in various applications, the elastic modulus is preferably 270 cN / dtex or more, more preferably 300 cN / dtex or more.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited at all by this. The various characteristics of the present invention were evaluated by the following methods.
-Tensile strength / elongation, elastic modulus: Measured using Tensilon UCT-100 manufactured by Orientec Co., Ltd. according to the method described in JIS L1013.
Melt viscosity: A shear viscosity determined using a Capillograph Type 1B manufactured by Toyo Seiki Co., Ltd. under the conditions of a measurement temperature of 300 ° C. and a shear rate of 100 sec ⁻¹ .
Melting point MP: In the differential calorimetry performed by a differential scanning calorimeter (DSC) manufactured by PerkinElmer Co., Ltd., the endothermic peak temperature (Tm ₁ ) observed when the temperature is measured at room temperature from 16 ° C./min. After observation, after holding for 5 minutes at a temperature of Tm ₁ + 20 ° C., after rapidly cooling to room temperature (holding for 5 minutes by combining the rapid cooling time and room temperature holding time), when measuring again at 16 ° C./min. The observed endothermic peak temperature (Tm ₂ ) was defined as the melting point MP.
・ Abrasion resistance: As the evaluation sample, a monofilament obtained by heat-treating a spun sample (multifilament) and then separating it is used, and the contact angle is set on a φ5 mm satin metal rod installed on a horizontally moving pulley. The end of the sample applied at 35 ° is held by a stroke device, a load of 2.0 cN / dtex is suspended in the horizontal movement direction of the pulley, and the stroke device is operated at a stroke length of 30 mm and a speed of 100 times / min. The sample was rubbed with a stick, and the number of strokes when fluff (component peeling, fibrillation) occurred was measured. The measurement was carried out five times, and the case where all the five measurements were 500 times or more was evaluated as ◯, and the case where less than 500 times was even one time was evaluated as x.
・ Dispersion state and component confirmation of sea component and island component, ratio of island component diameter to fiber diameter r / R: Observe fiber cross section using transmission electron microscope (TEM (H-800 type manufactured by Hitachi, Ltd.)) Was determined by Regarding the ratio r / R of the island component diameter to the fiber diameter, for the three fiber cross sections arbitrarily selected per sample, the circumscribed circle (R) of the fiber diameter in the fiber cross section and the fiber cross section By calculating the circumscribed circle (r) of the island component in the largest island component, the ratio r / R is calculated from the diameters of both circumscribed circles, and the average value of the ratio r / R determined for each of the three fiber cross sections. Was used as an evaluation value.
-Effect of suppressing increase in melt viscosity: After the polymer was discharged, the amount of increase in pack pressure for 5 hours after the spinning pack pressure was stabilized was used as an index of the effect of suppressing the increase in melt viscosity, and the increase amount was less than 1.0 MPa.
-Spinning property: The case where there was no spinning trouble during spinning for 5 hours and stable winding was evaluated as ○, and the case where spinning trouble occurred even once during spinning was evaluated as x.

Example 1
The molten liquid crystal forming polyester (A) is composed of a structural unit (1) generated from p-hydroxybenzoic acid and a structural unit (2) generated from 6-hydroxy-2-naphthoic acid. A molten liquid crystal forming polyester in which 72 mol% and the structural unit (2) accounted for 28 mol% was used. The melt viscosity of the molten liquid crystal forming polyester (A) was 115 Pa · s and the melting point was 278 ° C. under the measurement conditions of a measurement temperature of 300 ° C. and a shear rate of 100 sec ⁻¹ .

As polyphenylene sulfide (B), linear polyphenylene sulfide having a polymer chain terminal at the COOH terminal was used. This polyphenylene sulfide (B) had a melt viscosity of 51 Pa · s and a melting point of 280 ° C. under measurement conditions of a measurement temperature of 300 ° C. and a shear rate of 100 sec ⁻¹ .

  Both the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B) were dried at 150 ° C. for 10 hours under vacuum.

  The dried molten liquid crystal forming polyester (A) chip and the polyphenylene sulfide (B) chip were mixed at a composite weight ratio: WA / WB = 60/40 (wt%) while blowing nitrogen gas. This total weight: 100 parts by weight of WA + WB was added, 0.5 parts by weight of terephthalic acid (TPA) was added as an aromatic dicarboxylic acid monomer, and further mixed while blowing nitrogen.

  The mixed polymer is supplied to a twin screw extruder with a screw diameter of 30 mm directly connected to the melt spinning apparatus, melted and kneaded, then measured with a metering pump and supplied to the spinning pack, and the filtration diameter in the spinning pack is 15 μm. After filtration through a non-woven fabric filter, it was discharged from a single component die having a nozzle diameter of 0.13 mm, a nozzle length of 0.26 mm, and a hole number of 24 holes at a spinning temperature of 315 ° C., wound at a spinning speed of 600 m / min, and a 240 dtex filament Got.

  At this time, there is no discharge hole clogging, no discharge bending, etc., the spinning property is good, and the spinning pack pressure is 11.5 MPa at the initial stable time, 11.8 MPa after 5 hours from the stabilization, an increase of 0.3 MPa. And it was good. During this time, it was possible to perform stable spinning without breaking the yarn.

  In the obtained filament, the island component was composed of molten liquid crystal forming polyester (A) and the sea component was polyphenylene sulfide (B), and the dispersion state of the sea island component was good. Further, the ratio r / R of the maximum island component diameter to the fiber diameter was 0.13.

  A solid phase polymerization oil was applied to the filament, and solid phase polymerization was performed by heat treatment in a nitrogen gas atmosphere at 250 ° C. for 5 hours, 260 ° C. for 4 hours, and 280 ° C. for 12 hours. The obtained heat treated yarn had the following performance.

Strength 14.1 cN / dtex
Elongation 3.9%
Elastic modulus 335cN / dtex
Moreover, when the heat-treated yarn was divided and the abrasion resistance was evaluated as a monofilament, all of the five measurements achieved 500 times or more, which was regarded as acceptable.

Example 2
A filament is obtained by spinning in the same manner as in Example 1 except that the composite weight ratio of the melt liquid crystal forming polyester (A) and the polyphenylene sulfide (B) is changed to WA / WB = 15/85 (% by weight). It was. At this time, there is no discharge hole clogging, no discharge bending, etc., the spinning property is good, and the spinning pack pressure is initially stable: 7.8 MPa, after 5 hours of stabilization: 8.1 MPa, an increase of 0.3 MPa Met. During this time, it was possible to perform stable spinning without breaking the yarn.

  In the obtained filament, the island component was composed of molten liquid crystal forming polyester (A) and the sea component was polyphenylene sulfide (B), and the dispersion state of the sea island component was good. The ratio r / R of the island component diameter to the fiber diameter was 0.02.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. As a result of dividing the obtained heat-treated yarn and evaluating the wear resistance as a monofilament, all of the five measurements achieved 500 times or more, which was regarded as acceptable. Various evaluation results are shown in Table 1.

Example 3
A filament was obtained by spinning in the same manner as in Example 1 except that the composite weight ratio of the melt liquid crystal forming polyester (A) and the polyphenylene sulfide (B) was changed to WA / WB = 85/15 (wt%). It was. At this time, there is no discharge hole clogging, no discharge bending, etc., and the spinning property is good, and the spinning pack pressure is 10.4 MPa at the initial stable time, and 11.1 MPa after a lapse of 5 hours, and increases by 0.7 MPa. Met. During this time, it was possible to perform stable spinning without breaking the yarn.

  The obtained filament was composed of polyphenylene sulfide (B) as the island component and melted liquid crystal-forming polyester (A) as the sea component, and exhibited a mode opposite to the dispersed state of Example 1. The dispersion state of polyphenylene sulfide (B), which is an island component, was good, and the ratio r / R of the island component diameter to the fiber diameter was 0.03.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. The obtained heat-treated yarn had interfiber sticking and had poor unwinding properties. Moreover, when the heat-treated yarn was divided and the abrasion resistance was evaluated as a monofilament, fibrils were easily generated, and all the five measurements could not be achieved because the condition of 500 times or more could not be achieved. Various evaluation results are shown in Table 1.

Example 4
As polyphenylene sulfide (B), the same method as in Example 1 was used, except that the polyphenylene sulfide (B) had a melt viscosity of 242.0 Pa · s and a melting point of 283 ° C. under measurement conditions of a measurement temperature of 300 ° C. and a shear rate of 100 sec ^−1. A filament was obtained by spinning. At this time, there is no discharge hole clogging, no discharge bending, etc., the spinning property is good, and the spinning pack pressure is 13.8 MPa at the time of initial stabilization: 14.6 MPa after 5 hours of stabilization: an increase of 0.8 MPa Met. During this time, it was possible to perform stable spinning without breaking the yarn.

  Although the obtained filament had a co-continuous phase in which the dispersed state was not clear, the island component was generally composed of a melt liquid crystal forming polyester (A) and the sea component was composed of polyphenylene sulfide (B).

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. When the obtained heat-treated yarn was separated and the abrasion resistance was evaluated as a monofilament, fibrils were easily generated, and all the five measurements could not be performed because the conditions of 500 times or more could not be achieved. Various evaluation results are shown in Table 1.

Example 5
A filament was obtained by spinning in the same manner as in Example 1 except that the addition amount of terephthalic acid was changed to 0.2 parts by weight. At this time, there is no discharge hole clogging, no discharge bending, etc., and the spinning property is good, and the spinning pack pressure is 12.1 MPa at the initial stability, and after 1 hour 5 hours after the stabilization, it rises by 0.9 MPa at 13.0 MPa. Met. During this time, it was possible to perform stable spinning without breaking the yarn.

  In the obtained filament, the island component was composed of molten liquid crystal forming polyester (A) and the sea component was polyphenylene sulfide (B), and the dispersion state of the sea island component was good. The ratio r / R of the island component diameter to the fiber diameter was 0.13.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. As a result of dividing the obtained heat-treated yarn and evaluating the wear resistance as a monofilament, all of the five measurements achieved 500 times or more, which was regarded as acceptable. Various evaluation results are shown in Table 1.

Example 6
A filament was obtained by spinning in the same manner as in Example 1 except that the addition amount of terephthalic acid was changed to 3.0 parts by weight. At this time, there is no discharge hole clogging, no discharge bending, etc., the spinning property is good, and the spinning pack pressure is initially stable: 12.3 MPa, after 5 hours of stabilization: 13.1 MPa, an increase of 0.8 MPa Met. During this time, it was possible to perform stable spinning without breaking the yarn.

  In the obtained filament, the island component was composed of molten liquid crystal forming polyester (A) and the sea component was polyphenylene sulfide (B), and the dispersion state of the sea island component was good. The ratio r / R of the island component diameter to the fiber diameter was 0.13.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. As a result of dividing the obtained heat-treated yarn and evaluating the wear resistance as a monofilament, all of the five measurements achieved 500 times or more, which was regarded as acceptable. Various evaluation results are shown in Table 1.

Example 7
A filament is obtained by spinning in the same manner as in Example 1 except that dimethyl terephthalate (DMT), which is an esterified terephthalic acid, is used as the aromatic dicarboxylic acid monomer and / or its esterified derivative added during spinning. It was. At this time, there is no discharge hole clogging, no discharge bending, etc., and the spinning property is good, and the spinning pack pressure is 9.5 MPa at the initial stable time, and after 10 hours of stabilization, it is 10.4 MPa and increases by 0.9 MPa. Met. During this time, it was possible to spin stably without breaking the yarn.

  In the obtained filament, the island component was composed of molten liquid crystal forming polyester (A) and the sea component was polyphenylene sulfide (B), and the dispersion state of the sea island component was good. The ratio r / R of the island component diameter to the fiber diameter was 0.13.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. As a result of dividing the obtained heat-treated yarn and evaluating the wear resistance as a monofilament, all of the five measurements achieved 500 times or more, which was regarded as acceptable. Various evaluation results are shown in Table 1.

Example 8
A filament is obtained by spinning in the same manner as in Example 1 except that diphenyl terephthalate (DPT), which is an esterified terephthalic acid, is used as the aromatic dicarboxylic acid monomer and / or its esterified derivative added during spinning. It was. At this time, there is no discharge hole clogging, no discharge bending, etc., and the spinning property is good, and the spinning pack pressure is 9.0 MPa at the time of initial stabilization, 9.9 MPa after 5 hours from stabilization, and increases by 0.9 MPa. Met. During this time, it was possible to spin stably without breaking the yarn.

  In the obtained filament, the island component was composed of molten liquid crystal forming polyester (A) and the sea component was polyphenylene sulfide (B), and the dispersion state of the sea island component was good. The ratio r / R of the island component diameter to the fiber diameter was 0.14.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. As a result of dividing the obtained heat-treated yarn and evaluating the wear resistance as a monofilament, all of the five measurements achieved 500 times or more, which was regarded as acceptable. Various evaluation results are shown in Table 1.

Example 9
A filament was obtained by spinning in the same manner as in Example 1 except that the composite weight ratio of the melt-liquid crystal forming polyester (A) and the polyphenylene sulfide (B) was changed to WA / WB = 55/45 (wt%). It was. At this time, there is no discharge hole clogging, no discharge bending, etc., the spinning property is good, and the spinning pack pressure is 10.9 MPa at the initial stable time, and after 11 hours, it is 11.3 MPa and increases by 0.4 MPa. Met. During this time, it was possible to spin stably without breaking the yarn.

  In the obtained filament, the island component was composed of molten liquid crystal forming polyester (A) and the sea component was polyphenylene sulfide (B), and the dispersion state of the sea island component was good. The ratio r / R of the island component diameter to the fiber diameter was 0.11.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. As a result of dividing the obtained heat-treated yarn and evaluating the wear resistance as a monofilament, all of the five measurements achieved 500 times or more, which was regarded as acceptable. Various evaluation results are shown in Table 1.

Example 10
A filament is obtained by spinning in the same manner as in Example 1 except that the composite weight ratio of the melt liquid crystal forming polyester (A) and the polyphenylene sulfide (B) is changed to WA / WB = 75/25 (wt%). It was. At this time, there is no discharge hole clogging, no discharge bending, etc., and the spinning property is good, and the spinning pack pressure is 12.7 MPa at the time of initial stabilization, and after 1 hour of stabilization, it is 13.5 MPa and increases by 0.8 MPa. Met. During this time, it was possible to spin stably without breaking the yarn.

  In the obtained filament, the island component was composed of molten liquid crystal forming polyester (A) and the sea component was polyphenylene sulfide (B), and the dispersion state of the sea island component was good. The ratio r / R of the island component diameter to the fiber diameter was 0.22.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. As a result of dividing the heat-treated yarn obtained and evaluating the abrasion resistance as a monofilament, it was rejected only three times out of five measurements, which was rejected. Various evaluation results are shown in Table 1.

Comparative Example 1
Spinning was carried out in the same manner as in Example 1 except that the aromatic dicarboxylic acid monomer and / or esterified derivative thereof was not added.

  At this time, the spinning pack pressure was 12.0 MPa at the time of initial stabilization, 13.9 MPa after 5 hours had elapsed since the stabilization, and increased significantly to 1.9 MPa. During this time, yarn breakage occurred several times, making it difficult to wind up.

  When the composition of the sea-island component was evaluated with the portion of the filament that could be wound up, the island component was composed of molten liquid crystal forming polyester (A), the sea component was composed of polyphenylene sulfide (B), and the sea-island component was dispersed. The condition was good. The ratio r / R of the island component diameter to the fiber diameter was 0.14.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. As a result of dividing the obtained heat-treated yarn and evaluating the wear resistance as a monofilament, all of the five measurements achieved 500 times or more, which was regarded as acceptable. Various evaluation results are shown in Table 2.

Comparative Example 2
Spinning was carried out in the same manner as in Example 2, except that the aromatic dicarboxylic acid monomer and / or the esterified derivative thereof was not added.

  At this time, the spinning pack pressure was 8.0 MPa at the time of initial stabilization, 9.2 MPa after 5 hours had passed since the stabilization, and increased greatly to 1.2 MPa. During this time, yarn breakage occurred several times, making it difficult to wind up.

  When the composition of the sea-island component was evaluated with the portion of the filament that could be wound up, the island component was composed of molten liquid crystal forming polyester (A), the sea component was composed of polyphenylene sulfide (B), and the sea-island component was dispersed. The condition was good. The ratio r / R of the island component diameter to the fiber diameter was 0.03.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. As a result of dividing the obtained heat-treated yarn and evaluating the wear resistance as a monofilament, all of the five measurements achieved 500 times or more, which was regarded as acceptable. Various evaluation results are shown in Table 2.

Comparative Example 3
Spinning was carried out in the same manner as in Example 3 except that the aromatic dicarboxylic acid monomer and / or its esterified derivative was not added.

  At this time, the spinning pack pressure was 10.5 MPa at the time of initial stabilization, 11.9 MPa after 5 hours had elapsed after stabilization, and increased significantly to 1.4 MPa. During this time, yarn breakage occurred several times, making it difficult to wind up.

  When the polymer configuration of the sea-island component was evaluated with the portion of the filament that could be wound, the island component was composed of polyphenylene sulfide (B), and the sea component was composed of molten liquid crystal-forming polyester (A). A similar dispersion state was shown. Moreover, the dispersion state of polyphenylene sulfide (B), which is an island component, was good, and the ratio r / R of the island component diameter to the fiber diameter was 0.03.

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. When the obtained heat-treated yarn was separated and the abrasion resistance was evaluated as a monofilament, fibrils were easily generated, and all the five measurements could not be performed because the conditions of 500 times or more could not be achieved. Various evaluation results are shown in Table 2.

Comparative Example 4
Spinning was carried out in the same manner as in Example 4 except that the aromatic dicarboxylic acid monomer and / or the esterified derivative thereof was not added.

  At this time, the spinning pack pressure was 12.0 MPa at the time of initial stabilization, 13.5 MPa after 5 hours had passed since the stabilization, and increased significantly to 1.5 MPa. During this time, yarn breakage occurred several times, making it difficult to wind up.

  When the polymer composition of the sea-island component was evaluated with the portion of the filament that could be wound up, a co-continuous phase with an unclear dispersion state was present, but the island component was generally a melt liquid crystal-forming polyester (A), The sea component was composed of polyphenylene sulfide (B).

  In the same manner as in Example 1, an oil for solid phase polymerization was applied to this filament and heat treated. When the obtained heat-treated yarn was divided and the abrasion resistance was evaluated as a monofilament, fibrils were easily generated, and all the five measurements could not be achieved because the condition of 500 times or more could not be achieved. Various evaluation results are shown in Table 2.

Claims (7)

  In the method for producing a blend type composite fiber comprising a melt liquid crystal forming polyester (A) and a polyphenylene sulfide (B), an aromatic dicarboxylic acid monomer and / or an esterified derivative thereof is added and then melt spinning is performed. A method for producing a blend type composite fiber.   The total weight of the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B) is 100 parts by weight, and the aromatic dicarboxylic acid monomer and / or esterified derivative thereof is 0.2 to 3.0 parts by weight with respect to this. The method for producing a blend type composite fiber according to claim 1, wherein the blend type composite fiber is added.   The method for producing a blend type composite fiber according to claim 1 or 2, wherein terephthalic acid is used as the aromatic dicarboxylic acid monomer.   The blend according to any one of claims 1 to 3, wherein the island component has a sea-island structure in which the liquid crystal-forming polyester (A) and the sea component are composed of polyphenylene sulfide (B). A method for producing a mold composite fiber.   5. The composite weight ratio WA / WB is greater than 1 when the weight of the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B) is WA and WB, respectively. 5. The manufacturing method of the blend type | mold composite fiber as described in any one of.   The method for producing a blend type composite fiber according to claim 5, wherein the composite weight ratio WA / WB of the molten liquid crystal forming polyester (A) and the polyphenylene sulfide (B) is 1.2 to 3.0.   In the fiber cross section, when the fiber diameter is (R) and the island component diameter is (r), all the island components satisfy r / R ≦ 0.3 and are dispersed throughout the fiber cross section. The manufacturing method of the blend type composite fiber of any one of Claims 1-6 characterized by these.