JP2015193953A - Composite fiber comprising thermoplastic elastomer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite fiber having extremely excellent property in vibration damping performance.SOLUTION: There is provided a composite fiber constituted by at least one kind of polymer selected from a polymer having a glass transition temperature in a range of -40 to 30°C, a polymer having a polymer part having a glass transition temperature in a range of -40 to 30°C in its molecule structure, a thermoplastic elastomer having a melting viscosity at 250°C of 700 to 3000 poise (A Component) and easily soluble or easily degradable thermoplastic polymer (B Component) where the B Component coats 80% or more of fiber cross section peripheral length in a fiber cross section. The sheath component may be an easily resolvable polyester, a thermoplastic polyvinyl alcohol-based polymer or the like. A composite ratio (mass ratio) of a core part and a sheath part may be core:sheath=90:10 to 40:60.

Description

  The present invention relates to a composite fiber made of a thermoplastic elastomer having extremely excellent vibration damping performance.

In recent years, with the change of lifestyle, the demand for quietness has attracted attention, and a better damping material has become necessary. As fiber materials, various uses such as walls, flooring materials, and carpet materials are expected.
However, as described in Patent Document 1, conventional fiber materials are those in which synthetic fibers are arranged in the length and width directions and weight-laminated to define the arrangement ratio, and as in Patent Document 2, polyethylene terephthalate There are things that can be expected as a vibration damping material, such as those in which the fibers are unstretched with non-stretched fibers and then heat-shrinked into a dense structure, but the effect is not sufficient because the constituent fibers themselves do not have vibration damping performance It was. A material such as rubber can be considered as the material itself having vibration damping performance, but when unraveling a fiber that is produced by severe fiber sticking even if this material is spun in the same way as conventional synthetic fibers. However, there was a problem that yarn unwinding from a package was inferior in so-called unwinding property, fluff was generated, and fibers were cut.

Japanese Patent Publication No.55-42175 JP-A-60-199958

  An object of the present invention is to provide a fiber material itself that is excellent in vibration damping performance in the operating temperature range, and that has excellent unwinding properties from the package.

  As a result of intensive studies on fibers having excellent vibration damping performance and excellent unwinding properties from the package, the present inventors have determined that a specific thermoplastic elastomer and a readily soluble or easily decomposable heat The present inventors have found that a composite fiber composed of a plastic polymer exhibits excellent vibration damping performance near normal temperature and exhibits good unwinding properties, and has reached the present invention.

  That is, the present invention is selected from a polymer having a glass transition temperature in the range of −40 to 30 ° C. or a polymer having a polymer portion in the molecular structure having a glass transition temperature in the range of −40 to 30 ° C. And a thermoplastic elastomer (component A) having a melt viscosity of 700 to 3000 poise at 250 ° C. and a readily soluble or easily decomposable thermoplastic polymer (component B). In the fiber cross-section, the B component is a composite fiber covering 80% or more of the fiber cross-sectional circumference.

  In the composite fiber, the thermoplastic elastomer is a polymer block (a) having a number average molecular weight of 2500 to 60000 comprising a vinyl aromatic compound and a polymer block having a number average molecular weight of 10,000 to 200,000 comprising a conjugated diene compound (b And a block copolymer having a number average molecular weight of 30,000 to 300,000 and / or a hydrogenated product thereof.

  In the composite fiber, the component B is preferably formed of at least one selected from a readily soluble polyester and a thermoplastic polyvinyl alcohol polymer.

  The composite fiber preferably has a single fiber fineness of 0.3 to 50 dtex.

  The composite fiber preferably has a composite ratio (mass ratio) of the A component and the B component of A: B = 90: 10 to 40:60.

  The composite fiber preferably has a core-sheath structure in which the A component is a core component and the B component is a sheath component.

  The present invention also includes a preparation step for preparing the conjugate fiber, a conjugate fiber fabric producing step for producing a fabric composed of conjugate fibers using the conjugate fiber, and removing B component from the fabric to heat And a removal step of obtaining a thermoplastic elastomer fabric.

  Furthermore, this invention includes the thermoplastic elastomer fabric manufactured with the said manufacturing method.

  It should be noted that any combination of at least two components disclosed in the claims and / or the specification and / or the drawings is included in the present invention. In particular, any combination of two or more of the claims recited in the claims is included in the present invention.

  According to the present invention, a fiber having excellent vibration damping performance and excellent unwinding property can be obtained, and can be suitably used for various applications that require these characteristics.

Sectional drawing which shows the composite form of the composite fiber of this invention. The other sectional view showing the compound form of the conjugate fiber of the present invention. The other sectional view showing the compound form of the conjugate fiber of the present invention. The other sectional view showing the compound form of the conjugate fiber of the present invention. The other sectional view showing the compound form of the conjugate fiber of the present invention.

  Hereinafter, embodiments of the present invention will be described in detail. The composite fiber of the present invention is a polymer having a glass transition temperature in the range of −40 to 30 ° C. or a polymer having a polymer portion in the molecular structure having a glass transition temperature in the range of −40 to 30 ° C. A thermoplastic elastomer (component A) that is at least one polymer selected and has a melt viscosity at 250 ° C. of 700 to 3000 poise, and a readily soluble or easily decomposable thermoplastic polymer (component B) It is important that The A component and the B component may be compatible with each other at the interface, but are preferably incompatible with each other. First, details of each component will be described.

(Component A)
The thermoplastic elastomer forming the component A of the composite fiber of the present invention includes a polymer having a glass transition temperature in the range of −40 ° C. to 30 ° C. and a polymer having a glass transition temperature in the range of −40 ° C. to 30 ° C. It is comprised from the at least 1 sort (s) of polymer chosen from the polymer which has a part in the molecular structure. In addition, the glass transition temperature here means a glass transition temperature when measured by a differential scanning calorimetry (DSC), and details thereof are as described in the section of the following examples.

  The thermoplastic elastomer (component A) of the present invention has a glass transition temperature in the range of −40 ° C. to 30 ° C. or a glass transition temperature in the range of −40 ° C. to 30 ° C. described above. By having the coalescence part, it has a large tangent loss (hereinafter sometimes referred to as “tan δ”) at around room temperature, which is high in the conjugate fiber of the present invention and the thermoplastic elastomer fabric obtained therefrom. Gives vibration control performance. Instead of the thermoplastic elastomer (component A), a polymer having a glass transition temperature lower than −40 ° C. or higher than 30 ° C., or a polymer portion having a glass transition temperature in the range of −40 ° C. to 30 ° C. Even if a similar composite fiber is produced using a polymer that does not have a molecular structure, the thermoplastic elastomer fabric obtained from such a composite fiber does not exhibit vibration damping performance at the use temperature, and is an object of the present invention. Cannot be achieved.

  In the present invention, as the thermoplastic elastomer (component A), a polymer having a glass transition temperature in the range of −40 ° C. to 30 ° C. and / or a polymer portion having a glass transition temperature in the range of −40 ° C. to 30 ° C. Any polymer can be used as long as it has a molecular structure. Examples of the polymer having a glass transition temperature of −40 ° C. to 30 ° C. and the polymer portion having a glass transition temperature in the range of −40 ° C. to 30 ° C. include 1 of conjugated diene compounds such as butadiene, isoprene, and chloroprene. A homopolymer obtained from a seed, a random copolymer comprising two or more of the conjugated diene compounds, a block copolymer, a graft copolymer; or a polymer portion comprising the above-described polymer or copolymer Can be mentioned in the molecular structure.

  And in this invention, the polymer which has the polymer part which has a glass transition temperature in the range of -40 degreeC-30 degreeC in a molecular structure as a thermoplastic elastomer (A component) is used preferably. Among them, a polymer block (b) having a polymer block (a) made of a vinyl aromatic compound in the molecule and having a glass transition temperature in the range of −40 ° C. to 30 ° C. is included. A copolymer contained in the molecule (hereinafter sometimes referred to as a block copolymer (A1)) is preferably used. In the block copolymer (A1), the polymer block (a) includes not only a vinyl aromatic compound alone but also a polymer block obtained by polymerization of a monomer mixture mainly composed of a vinyl aromatic compound. Can be mentioned. Specific examples of the vinyl aromatic compound at that time include styrene, α-methylstyrene, 1-vinylnaphthalene, 2-vinylnaphthalene, 3-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, Examples thereof include 2-ethyl-4-benzylstyrene and 4- (phenylbutyl) styrene, and styrene is most preferable. In addition, as the polymer block (b) having a glass transition temperature in the range of −40 ° C. to 30 ° C. in the block copolymer (A1), one kind of conjugated diene compounds such as butadiene, isoprene and chloroprene or A polymer block composed of a polymer and / or copolymer obtained by polymerizing two or more kinds (hereinafter sometimes referred to as a conjugated diene polymer block (b)) is preferred.

  In particular, in the present invention, the block copolymer (A1) is conjugated with a polymer block (a) comprising a vinyl aromatic compound polymer block having a number average molecular weight of 2500 to 60000 comprising a vinyl aromatic compound as described above. And a polymer block comprising a diene polymer block having a glass transition temperature of -40 ° C to 30 ° C and a number average molecular weight of 10,000 to 200,000, the number average molecular weight of which is 30000 to A block copolymer of 300,000 is preferred.

  At that time, in the block copolymer (A1), the content ratio of the polymer block (a) made of the vinyl aromatic compound is 5 to 60% by mass based on the mass of the block copolymer (A1). Preferably there is. When the proportion of the polymer block (a) composed of a vinyl aromatic compound in the block copolymer (A1) is less than 5% by mass, the block copolymer (A1) and, consequently, the block copolymer (A1) are thermoplastic. There exists a tendency for the mechanical property of the composite fiber made into an elastomer (A component) to become inadequate. On the other hand, when it exceeds 60% by mass, the viscosity of the block copolymer (A1) becomes high and the high-speed spinnability at the time of fiberization becomes extremely poor. Further, the effect of improving the vibration damping performance of the obtained thermoplastic elastomer fabric may not be sufficiently exhibited.

  In the block copolymer (A1), the conjugated diene polymer block (b) is a homopolymer block of isoprene, a copolymer block of isoprene and butadiene, or both. preferable. When the conjugated diene polymer block (b) is a copolymer block of isoprene and butadiene, the copolymer form of isoprene and butadiene is random, block, tapered or a copolymer form in which two or more of them are mixed Any of these may be used. And when a block copolymer (A1) consists of a polymer block (a) which consists of an above-mentioned vinyl aromatic compound, and a conjugated diene polymer block (b), the number average molecular weight of a block copolymer (A1) Is more preferably in the range of 80000 to 250,000 from the viewpoint of high-speed spinnability at the time of fiberization.

  Further, when the thermoplastic elastomer (component A) is a block copolymer in which the polymer block (a) and the polymer block (b) are combined in a block shape as described above, the block form is , A (ba) n or (ab) n (wherein n is an integer of 1 or more, preferably an integer of 1 to 10) is preferably used. Among these, as the thermoplastic elastomer (component A), a block copolymer having a block form represented by aba is more preferably used.

  In the block copolymer as described above that is preferably used as the thermoplastic elastomer (component A), in the conjugated diene polymer block (b), a part or all of the carbon-carbon double bonds in the block are present. Hydrogenation (hereinafter sometimes referred to as “hydrogenation”) may be performed. The hydrogenation rate when used after hydrogenation can be appropriately selected according to the heat resistance and weather resistance required for the composite fiber and the thermoplastic elastomer fabric obtained therefrom. From the viewpoint of heat resistance and weather resistance, the hydrogenation rate is generally preferably 50% or more, more preferably 70% or more, and 80% or more when higher heat resistance and weather resistance are required. It is more preferable that the hydrogenation rate is. When the conjugated diene polymer block (b) in the thermoplastic elastomer (component A) is hydrogenated, the thermal stability during fiberization is also improved.

  It is important that the thermoplastic elastomer (component A) of the present invention has a melt viscosity at 250 ° C. of 700 to 3000 poise. When the melt viscosity exceeds 3000 poise, the high-speed spinnability at the time of fiberization is remarkably poor, whereas when it is less than 700 poise, not only is the fiber easily broken during spinning, but the productivity is poor, and it was obtained. Since the strength of the fiber is low, it is not suitable.

  Moreover, the thermoplastic elastomer (component A) of the present invention may contain an additive as necessary as long as the effects of the present invention are not impaired. Examples of additives include mineral oil softeners such as paraffinic oil and naphthenic oil for improving fluidity during molding; calcium carbonate for the purpose of improving or increasing heat resistance, weather resistance, etc. Inorganic fillers such as talc, carbon black, titanium oxide, silica, clay, barium sulfate, magnesium carbonate; glass fiber for reinforcement, inorganic fiber or organic fiber such as carbon fiber; heat stabilizer; antioxidant; light stability An adhesive; an adhesive; a tackifier; a plasticizer; an antistatic agent; and a foaming agent. Among these additives, in order to further improve heat resistance and weather resistance, it is practically preferable to add a heat stabilizer, an antioxidant and the like.

(B component)
The easily soluble or easily decomposable thermoplastic polymer that is the B component of the conjugate fiber of the present invention can be melt-spun and is relatively soluble in a solvent or a drug as compared to the thermoplastic elastomer that is the A component. Or anything that can be easily decomposed can be used.
Examples of such a readily soluble polymer include thermoplastic polymers that can be dissolved and decomposed by water (including warm water), alkali, acid, and the like, and preferably an easily soluble polyester that can be dissolved and decomposed in alkali. Examples thereof include thermoplastic polymers and thermoplastic polyvinyl alcohol polymers that can be dissolved and decomposed in water. Examples of the easily decomposable polymer include biodegradable aliphatic polyester and polylactic acid.

  When using an easily soluble polyester-based polymer as the component B of the present invention, it is preferable to use a polyester having a high alkali dissolution rate. For example, a polar group-containing copolymer polyester or an aliphatic polyester can be employed.

Examples of the polar group-containing copolymer polyester include 1 to 5 mol% of an ester-forming sulfonic acid metal salt compound (for example, 5-sodium sulfoisophthalic acid, 5-potassium sulfoisophthalic acid, etc.) and a polyalkylene glycol (for example, polypropylene glycol). And a copolyester formed by copolymerizing 5-30 mol% of a poly _C1-4 alkylene glycol such as polyethylene glycol) and a conventionally used diol component and dicarboxylic acid component.

  Examples of the aliphatic polyester include polylactic acid; a polyester of an aliphatic diol and an aliphatic carboxylic acid such as poly (ethylene succinate), poly (butylene succinate), poly (butylene succinate-co-butylene adipate); Poly (glycolic acid), poly (3-hydroxybutyric acid), poly (3-hydroxyvaleric acid), poly (6-hydroxycaproic acid) and other polyhydroxycarboxylic acids; poly (ε-caprolactone) and poly (δ-valero) Poly (ω-hydroxyalkanoate) such as lactone). Of these aliphatic polyesters, polylactic acid is preferable, and polylactic acid may be poly D-lactic acid, poly L-lactic acid, or a mixture thereof.

  As the easily soluble polyester polymer, for example, when immersed in a 2% sodium hydroxide aqueous solution at 100 ° C. at a bath ratio of 1:30, for example, within 60 minutes, preferably within 45 minutes, more preferably within 30 minutes, Particularly preferred is an alkali-soluble polyester that dissolves (decomposes) almost completely within 15 minutes.

  On the other hand, when a water-soluble thermoplastic polyvinyl alcohol polymer is used as component B of the present invention, the polyvinyl alcohol polymer used has a viscosity average polymerization degree of 200 to 500 and a saponification degree of 90 to 99.99 mol% ( Polyvinyl alcohol having a melting point of 160 to 230 ° C. is preferable, and it may be a homopolymer or a copolymer, but from the viewpoint of melt spinnability, water solubility, and fiber properties. It is preferable to use a copolymerized polyvinyl alcohol modified with 0.1 to 20 mol% (preferably 5 to 15 mol%) of an α-olefin having 4 or less carbon atoms such as ethylene and propylene.

  As the water-soluble thermoplastic polyvinyl alcohol polymer, for example, when immersed in hot water at 100 ° C. at a bath ratio of 1:30, for example, within 60 minutes, preferably within 50 minutes, more preferably within 30 minutes, especially A thermoplastic polyvinyl alcohol polymer that dissolves (decomposes) almost completely within 15 minutes is preferred.

(Manufacturing method of composite fiber)
As long as the combination of the component A and the component B is determined, the composite fiber of the present invention can be fiberized using a conventionally known composite spinning apparatus. It can be produced by any spinning method such as a method of drawing after melt spinning at a low speed or a medium speed, a method of direct spinning and spinning at a high speed, and a method of drawing and false twisting simultaneously or subsequently after spinning.

  In the composite fiber of the present invention, the composite ratio of the A component and the B component is preferably such that A: B is 90:10 to 40:60 (mass ratio), more preferably 85:15 to 60:40 (mass). Ratio). When the component A exceeds 90% by mass, the high-speed spinnability at the time of fiberization becomes extremely poor, and when it is less than 40% by mass, the vibration damping performance becomes extremely poor.

In the cross section of the conjugate fiber of the present invention, the B component needs to cover the fiber surface. In order to secure a fiber product having good unwinding properties from the fiber package, it is important that the B component covers 80% or more of the fiber cross-sectional circumference. If the coverage is less than 80%, the yarn release from the package, so-called unwinding property, is inferior, which is not suitable. Preferably it is 90 to 100%, more preferably 95 to 100%.

  The composite form of the present invention may be a concentric type, an eccentric type, or a multi-core type as long as the B component can be dissolved and removed by alkali treatment, water treatment, etc., and the A component does not crack. A core-sheath type composite structure in which the A component as shown in FIG. 1 is a core component and the B component is a sheath component, and an A-island component as shown in FIG. The structure is a composite structure in which the A component as shown in FIG. 3 is the core, and the periphery is intermittently covered by the B component, and the triangular structure as shown in FIG. 4 is a composite structure in which the B component is covered. Also good. In addition, the fiber cross-sectional shape of the component A may be a circular cross-sectional shape, or may be an irregular cross-sectional shape such as a triangle, a flat shape, or a multi-leaf type. Furthermore, it is possible to provide a hollow portion inside the component A as shown in FIG. 5, and there is no problem even if it has various cross-sectional shapes such as a hollow shape such as a hollow with a single hole or a hollow with two or more holes. Among these, the composite fiber preferably has a core-sheath type composite structure in which the A component is a core component and the B component is a sheath component.

  The single fiber fineness of the conjugate fiber of the present invention can be appropriately set according to the purpose, and is not particularly limited, and can be selected from the range of, for example, 0.3 to 50 dtex, preferably 0.3 to 40 dtex. In the composite fiber of the present invention, a fiber having a fineness of 6 dtex or less can be obtained while preventing yarn breakage. These fibers can be used not only as long fibers but also as short fibers or shortcuts.

  The composite fiber of the present invention obtained as described above can be used as various fiber assemblies (fiber structures). Here, examples of the fiber assembly include various woven and knitted fabrics and fabrics such as nonwoven fabrics.

  In addition, by removing the B component from these fiber aggregates, it is possible to obtain a final product having excellent vibration damping performance, that is, a fabric composed only of the thermoplastic elastomer (A component).

  For example, a fabric made of such a thermoplastic elastomer includes a preparation step of preparing the conjugate fiber, a conjugate fiber fabric production step of producing a fabric composed of conjugate fibers using the fibers, and the fabric. And removing the component B to obtain a fabric made of a thermoplastic elastomer.

  The composite fiber fabric may be formed of the composite fiber of the present invention alone, but a woven or knitted fabric or non-woven fabric made of a part of the composite fiber of the present invention, such as natural fiber, chemical fiber, synthetic fiber, etc. It may be a cross-woven fabric with other fibers such as a fiber, a blended yarn, a woven or knitted fabric used as a blended yarn, a mixed cotton nonwoven fabric, or the like. For example, when used in combination with other fibers, the proportion of the component A of the composite fiber of the present invention in the woven or knitted fabric or nonwoven fabric may be, for example, 14% by mass or more, preferably 15% by mass or more, preferably It may be 18% by mass or more, more preferably 23% by mass or more. When used as a blended yarn or a blended yarn, the proportion of the component A in the yarn may be, for example, 14 to 95% by mass, preferably 20% by mass or more, preferably 30% by mass or more, and more preferably. 40 mass% or more may be sufficient.

  A fabric made of a thermoplastic elastomer fiber obtained by removing the B component from a composite fiber fabric by alkali treatment, water treatment or the like has excellent vibration damping properties. In addition, by using the composite fiber used in the present invention, the single fiber fineness of the fiber made of the thermoplastic elastomer constituting the fabric is, for example, in the range of 0.3 to 50 dtex, preferably 0.3 to 40 dtex. When the fineness is reduced, it is possible to obtain a fineness fiber of 0.3 to 10 dtex, preferably 0.3 to 5 dtex.

  The composite fiber fabric or the fabric made of the thermoplastic elastomer may be subjected to a raising process such as raising a needle cloth or other finishing process as necessary after passing through the fabric forming step.

  The fiber of the present invention can be used as a long fiber, or can be cut as appropriate and used as a short fiber. And since fabrics, such as a woven fabric, a knitted fabric, and a nonwoven fabric, can be manufactured, it uses suitably for various textiles.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In addition, each physical property value in an Example means what was measured with the following measuring methods.

[Glass transition temperature (℃)]
The glass transition temperature (Tg) of the thermoplastic elastomer was obtained by collecting a part of polymer pellets and using a differential thermal scanning calorimeter (“TA-4000” manufactured by METTLER) with a temperature increase rate of 10 ° C. / Measured in minutes.

[Melt viscosity]
The melt viscosity of the thermoplastic elastomer was measured using a Capillograph 1C PMD-C manufactured by Toyo Seiki Seisakusho under the conditions of 250 ° C. and a shear rate of 1000 sec ⁻¹ .

[Vibration control performance]
The vibration damping performance (tan δ) at 25 ° C. was measured using a Leo vibron manufactured by Orientik.

[Basis weight of fabric (g / m ² )]
It measured according to JIS P8124.

[Thickness of fabric (mm), density of fabric (g / m ³ )]
The woven fabric composed of the obtained fibers is left in a standard environment (temperature 20 ° C., relative humidity 65%) for 4 hours or more, and then PEACOCK Dial-Thickness Gauge H Type (manufactured by Yasuda Seiki Seisakusho; φ10 mm × 180 g / cm ² ). The thickness is measured at 5 points, and the average value is expressed as the thickness of the fabric. The density was calculated by dividing the basis weight by the thickness.

[Unsolvability from the package]
Using a take-up machine, take up the unwound fiber at a speed of 200 m / min.
The unraveling property was evaluated according to the following criteria.
○: 300 breaks at a breaking speed of 200 m / min, no breakage occurs, and no fluff or loops occur in the obtained fiber.
X: 300 resolving wrinkles are carried out at a unwinding speed of 200 m / min, yarn breakage occurs one or more times, and one or more fluffs and loops occur in the obtained fiber, resulting in poor unwinding properties.

[B component coverage in fiber cross section (%)]
From the fiber cross-section photograph, for 10 randomly selected filaments, the length of the fiber coating portion of each filament is measured, and the percentage of the coating portion length with respect to the fiber cross-section circumference is calculated as the coverage, and the average coverage of each filament The value was determined.

[Spinnability evaluation]
The evaluation was based on the occurrence of fluff and breakage when spinning 100 kg.
○: No fluff or yarn breakage during spinning △: Fluff or yarn breakage during spinning is recognized twice or less ×: Fluff or yarn breakage during spinning three or more times

[Reference Example 1]
A pressure-resistant container purged with nitrogen and dried was charged with 3000 ml of cyclohexane as a solvent and 4.6 ml of sec-butyllithium (cyclohexane solution) with a concentration of 10.5% by mass as an initiator. After heating to 50 ° C., styrene was added. 320 ml was added and polymerized for 60 minutes.
Thereafter, the temperature is lowered to 40 ° C., 25 ml of THF is added, 10 ml of a 50/50 (mass ratio) mixture of isoprene and butadiene is added and reacted, and after 3 minutes, the same amount of isoprene and butadiene is 50/50. (Mass ratio) is added and reacted repeatedly. Finally, a total of 450 ml of a mixture of isoprene and butadiene is added, and then the reaction is continued for another 150 minutes. Then, the polymerization is stopped with 0.26 ml of methanol. A polymerization reaction solution containing a block copolymer was obtained. A Ziegler-type hydrogenation catalyst formed from nickel octylate and triethylaluminum was added to the polymerization reaction solution obtained above in a hydrogen atmosphere, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and 80 ° C. for 5 hours. Then, a hydrogenated product (1) of a block copolymer was obtained.

[Reference Example 2]
A pressure-resistant container purged with nitrogen and dried was charged with 3000 ml of cyclohexane as a solvent and 10.5 ml of sec-butyllithium (cyclohexane solution) with a concentration of 10.5% by mass as an initiator. After heating to 50 ° C., styrene was added. 90 ml was added and polymerized for 60 minutes.
Thereafter, the temperature was lowered to 40 ° C., 17 ml of THF was added, 900 ml of isoprene was added, polymerization was performed for 4 hours, and 90 mL of styrene was further added for polymerization for 3 hours. Thereafter, the polymerization was stopped with 0.60 ml of methanol to obtain a polymerization reaction solution containing a block copolymer. A Ziegler-type hydrogenation catalyst formed from nickel octylate and triethylaluminum was added to the polymerization reaction solution obtained above in a hydrogen atmosphere, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and 80 ° C. for 5 hours. Then, a hydrogenated product (2) of a block copolymer was obtained.

[Reference Example 3]
A pressure-resistant container purged with nitrogen and dried was charged with 3000 ml of cyclohexane as a solvent and 2.9 ml of sec-butyllithium (cyclohexane solution) with a concentration of 10.5% by mass as an initiator. After heating to 50 ° C., styrene was added. 30 ml was added and polymerized for 60 minutes.
Thereafter, 1.7 ml of TMEDA was added, 650 ml of butadiene was added and polymerization was performed for 4 hours, and further 30 mL of styrene was added and polymerization was performed for 3 hours. Thereafter, the polymerization was stopped with 0.16 ml of methanol to obtain a polymerization reaction solution containing a block copolymer. A Ziegler-type hydrogenation catalyst formed from nickel octylate and triethylaluminum was added to the polymerization reaction solution obtained above in a hydrogen atmosphere, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and 80 ° C. for 5 hours. Then, a hydrogenated product (3) of a block copolymer was obtained.

[Reference Example 4]
A pressure-resistant container purged with nitrogen and dried was charged with 3000 ml of cyclohexane as a solvent and 19 ml of sec-butyllithium (cyclohexane solution) with a concentration of 10.5% by mass as an initiator. After heating to 50 ° C., 120 ml of styrene was added. For 60 minutes.
Thereafter, 750 ml of isoprene was added for polymerization for 2 hours, and 120 mL of styrene was further added for polymerization for 3 hours. Thereafter, the polymerization was stopped with 1.1 ml of methanol to obtain a polymerization reaction solution containing a block copolymer. A Ziegler-type hydrogenation catalyst formed from nickel octylate and triethylaluminum was added to the polymerization reaction solution obtained above in a hydrogen atmosphere, and a hydrogenation reaction was carried out at a hydrogen pressure of 0.8 MPa and 80 ° C. for 5 hours. Then, a hydrogenated product (4) of a block copolymer was obtained.

  The block copolymer hydrogenated products (1) to (4) obtained in Reference Examples 1 to 4 are summarized in Table 1 below. The block (a) represents a polymer block composed of a styrene polymer block, and the block (b) represents a conjugated diene polymer block. The number average molecular weight was calculated by polystyrene conversion using GPC.

(Example 1)
As the component A, the hydrogenated product (1) of the block copolymer obtained in Reference Example 1 was used. On the other hand, as the component B, 8 mol% of polyethylene glycol having a molecular weight of 2000 and 5 mol% of 5-sodium sulfoisophthalic acid were used. Using a copolymerized polyethylene terephthalate having an intrinsic viscosity [η] of 0.52, the composite ratio of component A and component B is 75:25, and each is melted in a separate extruder, and the core shown in FIG. The composite fiber was discharged from the composite spinning nozzle at the sheath cross section.

  Next, after the yarn discharged from the spinneret was cooled by a horizontal blowing type cooling air device having a length of 1.0 m, it was continuously installed at a position of 1.3 m from directly below the spinneret and an inner diameter of 1.0 m. After introducing into a 30 mm tube heater (inner wall temperature: 180 ° C.) and drawing in the tube heater, an oil agent is applied to the fiber coming out of the tube heater, and subsequently at a take-up speed of 3000 m / min via a roller. The composite fiber of 111 dtex / 24 filament was manufactured by winding.

The fiberization and knitting processability was good and no problem. A woven fabric having a basis weight of 46.4 g / m ² and a thickness of 0.296 mm was obtained from the obtained composite fiber. After scouring this fabric, it was immersed in an aqueous alkaline solution (liquid temperature: 100 ° C.) having a potential soda of 20 g / L and a bath ratio of 1:30 for 30 minutes to selectively dissolve and remove the component B. The vibration damping performance of the obtained fabric was good as shown in Table 2.

(Example 2)
Fibrosis, production of fabric and evaluation were performed in the same manner as in Example 1 except that the hydrogenated product (2) of the block copolymer obtained in Reference Example 2 was used as the component A of the composite fiber. The fiberization / weaving processability of the composite fiber was good, and the resulting woven fabric had excellent vibration damping performance as shown in Table 2.

(Example 3)
Fibrosis, creation of fabric and evaluation were performed in the same manner as in Example 1 except that polylactic acid (Cargill Dow, 6200D) was used as the B component of the composite fiber. The fiberization / weaving processability of the composite fiber was good, and the resulting woven fabric had excellent vibration damping performance as shown in Table 2.

Example 4
Thermoplastic modified polyvinyl alcohol (modified PVA) (manufactured by Kuraray Co., Ltd., degree of saponification: 98.5, ethylene content: 8.0 mol%, degree of polymerization: 380) is used as component B of the composite fiber, and water is used as the spinning oil. Except for using an antistatic agent component and a smoothing agent component that does not contain a fiber, fiberization was carried out in the same manner as in Example 1, and a woven fabric was produced in the same manner. Thereafter, the fabric was treated in hot water at 100 ° C. with a bath ratio of 1:30 for 40 minutes to dissolve and remove the component B. As shown in Table 2, the fiberization / knitting processability of the composite fiber was good, and the obtained woven fabric had good vibration damping performance.

(Examples 5-6)
Except that the composite ratio (mass ratio) of the A component and the B component of the composite fiber was changed as shown in Table 2, fiberization and production and evaluation of the woven fabric were performed in the same manner as in Example 1. As shown in Table 2, the fiberizing / knitting processability was good in any case, and the resulting woven fabrics all had excellent vibration damping performance.

(Examples 7 to 9)
Except that the cross-sectional shape of the composite fiber was changed as shown in Table 1, fiberization and production and evaluation of the woven fabric were performed in the same manner as in Example 1. In Example 8, fiber formation was performed using a modified nozzle for the spinneret. As shown in Table 2, the fiberizing / knitting processability was good in any case, and the resulting woven fabrics all had excellent vibration damping performance.

(Comparative Example 1)
It implemented by the method similar to Example 1 except not having used B component and not using it as the composite fiber. The fiberization processability was unsatisfactory, and the obtained fiber was inferior in unwinding property, making it impossible to produce a woven fabric.

(Comparative Example 2)
In the same manner as in Example 1 except that the A component and the B component were composite-spun in a side-by-side manner and the fiber cross section was changed so that the B component covered 50% of the total circumference of the A component. Carried out. The fiberization processability was unsatisfactory, and the obtained fiber was inferior in unwinding property, making it impossible to produce a woven fabric.

(Comparative Example 3)
In the same manner as in Example 1 except that the A component and the B component were composite-spun in a side-by-side manner and the fiber cross section was changed so that the B component covered 20% of the total circumference of the A component. Carried out. The fiberization processability was unsatisfactory, and the obtained fiber was inferior in unwinding property, making it impossible to produce a woven fabric.

(Comparative Example 4)
The same process as in Example 1 was performed using the product obtained in Reference Example 3. Spinning was impossible due to the high melt viscosity of the thermoplastic elastomer (component A).

(Comparative Example 5)
The same process as in Example 1 was performed using the product obtained in Reference Example 4. Although fiberization was good, only those with poor vibration damping performance were obtained.

  The main application of the composite fiber of the present invention is expected to be used in various ways such as walls, flooring materials and carpet materials by producing woven or knitted fabrics alone or in part.

  As described above, the preferred embodiment of the present invention has been described. However, those skilled in the art will readily consider various changes and modifications within the obvious scope by looking at the present specification. Accordingly, such changes and modifications are to be construed as within the scope of the invention as defined by the appended claims.

1: A component of composite fiber 2: B component of composite fiber 3: Hollow portion of composite fiber

Claims (8)

  At least one polymer selected from a polymer having a glass transition temperature in the range of −40 to 30 ° C. or a polymer having a polymer portion in the molecular structure having a glass transition temperature in the range of −40 to 30 ° C. And a thermoplastic elastomer (component A) having a melt viscosity of 700 to 3000 poise at 250 ° C. and a readily soluble or easily decomposable thermoplastic polymer (component B), and the component B in the fiber cross section Is a composite fiber that covers 80% or more of the fiber cross-sectional circumference.   The thermoplastic elastomer comprises a polymer block (a) having a number average molecular weight of 2500 to 60000 composed of a vinyl aromatic compound and a polymer block (b) having a number average molecular weight of 10,000 to 200,000 composed of a conjugated diene compound. The composite fiber according to claim 1, which is a block copolymer having a number average molecular weight of 30,000 to 300,000 and / or a hydrogenated product thereof.   The composite fiber according to claim 1 or 2, wherein the component B is formed of at least one selected from a readily soluble polyester and a thermoplastic polyvinyl alcohol-based polymer.   The composite fiber according to any one of claims 1 to 3, wherein the single fiber fineness is 0.3 to 50 dtex.   The composite fiber according to any one of claims 1 to 4, wherein a composite ratio (mass ratio) of the A component and the B component is A: B = 90: 10 to 40:60.   The composite fiber having a core-sheath structure according to any one of claims 1 to 5, wherein the A component is a core component and the B component is a sheath component.   A preparation step of preparing the conjugate fiber according to any one of claims 1 to 6, a conjugate fiber fabric production step of producing a fabric composed of conjugate fiber using the conjugate fiber, and B to B A method for producing a thermoplastic elastomer fabric, comprising a removing step of removing a component to obtain a thermoplastic elastomer fabric.   A thermoplastic elastomer fabric produced by the production method according to claim 7.

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