WO2021177168A1

WO2021177168A1 - Polyetherimide-based fibers, method for producing same, and textile product and composite material both including same

Info

Publication number: WO2021177168A1
Application number: PCT/JP2021/007363
Authority: WO
Inventors: 哲也友杉; 小泉　聡
Original assignee: 株式会社クラレ
Priority date: 2020-03-03
Filing date: 2021-02-26
Publication date: 2021-09-10

Abstract

Provided are: polyetherimide-based fibers useful as a matrix for composite materials; a textile product; and a composite material. The polyetherimide-based fibers are configured from a polyetherimide-based resin containing a polymerization solvent having a boiling point of 100°C or higher and have a content of the polymerization solvent of 250 ppm or less. The textile product is configured of the polyetherimide-based fibers. The composite material included a melt of the polyetherimide-based fibers as a matrix.

Description

Polyetherimide-based fibers and their manufacturing methods, as well as textile products and composite materials using them.

Related application

This application claims the priority of Japanese Patent Application No. 2020-35498, which was filed in Japan on March 3, 2020, and is cited as a part of this application by reference in its entirety.

The present invention uses polyetherimide-based fibers useful as a matrix of composite materials, various fiber products using polyetherimide-based fibers (for example, cloth), and composite materials using melts of the polyetherimide-based fibers as a matrix. Regarding.

Polyetherimide is a polymer that has excellent heat resistance and is also excellent in moldability because it has thermoplasticity. In addition, polyetherimide has high strength, high heat resistance, high elastic modulus and wide chemical resistance, and is widely used in various applications such as automobiles, telecommunications, aerospace, electrical / electronics, transportation, and healthcare. in use.

In general, polyetherimide is difficult to be fibrotic. For example, in Patent Document 1 (Patent No. 5659148), an amorphous polyetherimide having a molecular weight distribution (Mw / Mn) of less than 2.5. Disclosed are amorphous polyetherimide-based fibers which are fibers composed of a polymer and have a dry heat shrinkage rate of 5% or less at 200 ° C. and a single fiber fineness of 3.0 dtex or less. ing. In this document, even if it is a polyetherimide that is difficult to be fiberized, fine fibers having a single fiber fineness of 3.0 dtex or less can be obtained.

Japanese Patent No. 5659148

However, in the polyetherimide-based fiber described in Patent Document 1, a polymerization solvent having a high boiling point may remain in the polymer, and the fiber characteristics under high temperature (particularly the mechanical properties under high temperature tension conditions). There was a risk of affecting.

An object of the present invention is to use a polyetherimide-based fiber capable of achieving a breaking elongation similar to a breaking elongation at room temperature even under high-temperature tension conditions, a method for producing the same, and a polyetherimide-based fiber. To provide the product.
Another object of the present invention is to provide a composite material comprising a melt of such a polyetherimide-based fiber as a matrix.

As a result of diligent studies to solve the above problems, the present inventors have used a polymerization solvent having a high boiling point in (i) polyetherimide suitable for fibrosis, and for that purpose, a fibrosis step was carried out. In this case, it was found that a polymerization solvent having a high boiling point remains in the polymer, and (ii) degassing performed in a normal fibrosis step is not sufficient to solve this problem. Then, in the (iii) spinning step, when a specific degassing treatment is performed to reduce the content of the polymerization solvent, surprisingly, in the obtained fiber, the amount of the high boiling point polymerization solvent remaining in the polymer is reduced. Perhaps because of this, we found that the breaking elongation of polyetherimide fibers under tension conditions at high temperatures can be maintained at the same level as room temperature, and as a result, the breaking elongation retention rate can be improved compared to conventional products. The invention was completed.

That is, the present invention may be configured by the following aspects.
[Aspect 1]
A polyetherimide-based fiber made of a polyetherimide-based resin containing a polymerization solvent having a boiling point of 100 ° C. or higher (preferably 150 ° C. or higher), wherein the content of the polymerization solvent in the fiber is 250 ppm or less (preferably 200 ppm). It may be less than or equal to, more preferably 150 ppm or less), and is a polyetherimide-based fiber.
[Aspect 2]
The polyetherimide-based fiber according to the first aspect, which has a breaking elongation retention rate of 80% or more (preferably 82% or more) in an atmosphere of 190 ° C. with respect to an atmosphere of room temperature (20 ° C.), more preferably. Is 85% or more), a polyetherimide-based fiber.
[Aspect 3]
The polyetherimide-based fiber according to

aspect

1 or 2, wherein the polymerization solvent is dichlorobenzene, dichlorotoluene, trichlorobenzene, diphenylsulfone, monoalkoxybenzene, dialkoxybenzene, diphenyl ether, dimethylformamide, dimethylacetamide, dimethyl sulfoxide. , And a polyetherimide-based fiber which is at least one selected from the group consisting of N-methylpyrrolidinone.
[Aspect 4]
The method for producing a polyetherimide-based fiber according to any one of aspects 1 to 3.
It includes a step of melt-kneading a polyetherimide-based resin containing a polymerization solvent having a boiling point of 100 ° C. or higher, and a step of spinning.
In the melt-kneading step, the polyetherimide-based resin passes through a solid zone, a mixed zone of a solid and a melt, and a melt zone.
Vent openings are provided, at least in the solid zone and the melt zone.
A production method in which vacuum degassing is performed at a pressure of 0 to 50 mmHg (preferably 0 to 40 mmHg, more preferably 0 to 30 mmHg) at least in the melt zone at the vent port.
[Aspect 5]
The method for producing a polyetherimide-based fiber according to aspect 4, wherein vent ports are arranged in a solid zone, a mixing zone, and a melt zone.
[Aspect 6]
The method for producing a polyetherimide-based fiber according to aspect 4 or 5, wherein at least one kneading portion is arranged at a position between the vent openings.
[Aspect 7]
A textile product composed of the polyetherimide-based fiber according to any one of aspects 1 to 3.
[Aspect 8]
A composite material comprising the melt of the polyetherimide-based fiber according to any one of aspects 1 to 3 as a matrix.

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

According to the present invention, it is possible to obtain a polyetherimide-based fiber having better fiber properties than before even when exposed to a high temperature. Further, since such a polyetherimide-based fiber can maintain the elongation at break at a high temperature, it can be usefully used in designing various fiber products used at a high temperature.
Furthermore, when the polyetherimide is melted and used as a matrix, for example, even if a non-planar portion is present, it is possible to suppress defects that occur in the composite material due to the breakage of the stretched fibers. This makes it possible to obtain a composite material that can be easily molded into a complicated shape such as an automobile seat, a tank, or an aircraft air duct.

The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are for illustration and description purposes only and should not be used to define the scope of the invention. The scope of the present invention is determined by the appended claims.
It is schematic cross-sectional view for demonstrating an example of a mixing apparatus used in the melt kneading step of a polyetherimide-based fiber.

Hereinafter, the present invention will be described in detail. The first embodiment of the present invention is a polyetherimide-based fiber.

(Polyetherimide fiber)
The polyetherimide-based fiber is a polyetherimide-based fiber made of a polyetherimide-based resin containing a polymerization solvent having a boiling point of 100 ° C. or higher, and the content of the polymerization solvent in the fiber is 250 ppm or less. The polyetherimide-based fiber can be obtained by melt-spinning a polyetherimide-based resin.

(Polyetherimide resin)
The polyetherimide-based resin is a polymer containing an aliphatic, alicyclic or aromatic ether unit and a cyclic imide as repeating units, and has a fiber forming ability by melting. Further, as long as the effect of the present invention is not impaired, the main chain of the polyetherimide-based resin contains a cyclic imide, a structural unit other than the ether unit, for example, an aliphatic, alicyclic or aromatic ester unit, or an oxycarbonyl unit. Etc. may be contained.

As a specific polyetherimide, a polymer having a unit represented by the following general formula is preferably used. However, in the formula, R1 is a divalent aromatic residue having 6 to 30 carbon atoms; R2 is a divalent aromatic residue having 6 to 30 carbon atoms, and 2 to 20. 2 selected from the group consisting of a polydiorganosiloxane group chain-terminated with an alkylene group having 2 to 20 carbon atoms and an alkylene group having 2 to 8 carbon atoms. It is a valent organic group.

As the above R1 and R2, for example, those having an aromatic residue or an alkylene group (for example, m = 2 to 10) represented by the following formula group are preferably used.

The resin constituting the polyetherimide-based fiber preferably contains at least 50% by mass or more, more preferably 80% by mass or more, and 90% by mass or more of the polymer having the unit represented by the above general formula in the resin. It is more preferable, and it is particularly preferable to contain 95% by mass or more.

In the present invention, as the polyetherimide-based resin forming the polyetherimide-based fiber, a solvent having a boiling point of 100 ° C. or higher, particularly 150 ° C. or higher is used as the polymerization solvent. Examples of such a polymerization solvent include dichlorobenzene (eg, o-dichlorobenzene), dichlorotoluene, trichlorobenzene (eg, 1,2,4-trichlorobenzene), diphenylsulfone, monoalkoxybenzene (eg, anisole, etc.). Phenotor and the like), dialkoxybenzene (eg, veratrol, etc.), diphenyl ether, dimethylformamide, dimethylacetamide (eg, N, N-dimethylacetamide), dimethyl sulfoxide, N-methylpyrrolidinone and the like can be exemplified. These solvents may be used alone or in combination of two or more. The upper limit of the boiling point of the polymerization solvent is not particularly limited, but may be, for example, about 250 ° C.
Among these, particularly preferable polymerization solvents include o-dichlorobenzene and anisole.

The polyetherimide-based resin may contain various additives generally used for obtaining fibers. For example, as additives, a heat stabilizer, an antioxidant, an antistatic agent, and a radical inhibitor , Matters, UV absorbers, flame retardants, inorganic substances, and other polymers may be contained. These additives may be used alone or in combination of two or more. The amount of the additive may be generally about 0.005 to 10% by mass, specifically about 0.01 to 5% by mass, based on the total mass of the composition.

Such a polyetherimide-based resin contains 2,2-bis [4- (3,4-dicarboxyphenoxy) phenyl] propane dianhydride and m-phenylenediamine, which mainly have the structural unit represented by the above formula. The condensate of is preferably used. Such polyetherimides are commercially available from SABIC Innovative Plastics under the trademark "Ultem".

The polyetherimide-based resin obtained by polymerization is then subjected to a fibrosis step.
The method for producing a polyetherimide-based fiber of the present invention includes a step of melt-kneading a polyetherimide-based resin containing a polymerization solvent having a boiling point of 100 ° C. or higher, and a step of spinning. In the melt-kneading step, the polyetherimide-based resin can be melt-kneaded to obtain a molten polymer having a predetermined melt viscosity for spinning, and in the spinning step, the molten polymer can be melt-kneaded from a spinning nozzle in a predetermined amount. It can be discharged to form threads (or molten raw yarn).

When producing a polyetherimide-based fiber, the present invention is characterized in that the high boiling point polymerization solvent contained in the melted polyetherimide-based resin is highly removed in the melt-kneading step. First, the polyetherimide-based resin is usually sufficiently dried and then subjected to a melt-kneading step.

In the melt-kneading step, melt-kneading is performed in a mixing device that can strongly apply a shearing force to the material together with deaeration. Examples of the mixing device include a screw extruder (for example, a single-screw screw extruder and a twin-screw screw extruder), preferably a twin-screw screw extruder and the like. In the mixing apparatus, the polyetherimide-based resin is subjected to a spinning process through a solid zone, a mixing zone of a solid and a melt, and a melt zone.
For example, in a screw extruder, a polyetherimide-based resin is supplied as a solid (for example, a chip) such as a granular material, and the rotation of the screw inside the cylinder advances to a solid zone, a mixing zone, and a melt zone.

Here, the solid zone includes a solid bed which is a mass of resin granules and the like and a stage where a melt film obtained by melting the surface of the resin granules is formed, but a melt pool in which the melts are aggregated is formed. The stage of formation is not included.
The mixing zone includes the stage where the melt pool is formed, but the unmelted resin remains as a solid bed. Therefore, the mixing zone does not include a step in which the solid bed formed of the solid resin is destroyed and the unmelted material floats in the melted material.
The melt zone includes both the stage where the solid bed is broken and the unmelt floats in the melt and the stage where the resin is completely melted.

In the mixing device, a plurality of vent ports are provided in order to highly remove the high boiling point polymerization solvent contained in the polyetherimide-based resin. The plurality of vent ports are provided in any two or more zones selected from the solid zone, the mixed zone, and the melt zone, and are provided in at least the solid zone and the melt zone, and are provided in the solid zone, the mixed zone, and the melt zone. It is preferably provided in all of the zones. When the vent port is provided in the solid zone, it is possible to effectively utilize the first degassing of the polymerization solvent generated by the rapid temperature rise. By providing a vent port in the melt zone, it is possible to ensure that the polymerization solvent generated in the melt kneading step is finally degassed within a predetermined range. Further, a plurality of vent ports may be provided in one zone.

Of these vent ports, at least in the melt zone, vacuum degassing is performed while maintaining a pressure of 0 to 50 mmHg, preferably maintaining a pressure in the range of 0 to 40 mmHg, more preferably 0 to 30 mmHg. Deaeration may be performed. The vent ports where the vacuum degassing is performed are arranged at least in the melt zone, and preferably all of the vent ports may be vacuum degassed.

The melt-kneading step may be carried out at, for example, 290 ° C. or higher, more preferably 300 ° C. or higher, from the viewpoint of obtaining a close polymer mixture having no unmelted material as the resin to be used in the spinning step. Further, in order to avoid excessive polymer decomposition, it may be carried out at 370 ° C. or lower, more preferably 350 ° C. or lower.

In the screw extruder, for example, the L / D (L: screw length, D: screw diameter) may be 20 or more, preferably 25 or more, and more preferably 32 or more. The upper limit is not particularly limited, but may be 50 or less from the viewpoint of handling the screw.

For example, FIG. 1 is a schematic cross-sectional view for explaining an example of a mixing device used in a melt-kneading step of a polyetherimide-based fiber. As shown in FIG. 1, in a mixing device 10 such as a screw extruder, a polyetherimide-based resin is supplied as a resin chip 1, and the supplied resin is directed toward the traveling direction X by the rotation of the screw 6 inside the cylinder. , Solid zone 2, mixing zone 3, and melt zone 4.

Vent ports

5a, 5b, and 5c are arranged in the solid zone 2, the mixing zone 3, and the melt zone 4, respectively, and the polymerization solvent generated in the melt kneading step is discharged from these

vent ports

5a, 5b, and 5c. ..

Further, from the viewpoint of giving a strong shearing force, it is preferable to provide at least one kneading portion in the mixing device. Since a plurality of vent ports are provided, a kneading portion may be provided between the vent ports. In that case, for example, after vacuum degassing at the first vent port, the surface of the mixture and / or the melt at the kneading portion is renewed to further discharge the undegassed mood at the first vent port, and the second Vacuum degassing is possible from the vent port of.

The at least one kneading portion is preferably provided in the melt zone, and more preferably provided in the mixing zone and the melt zone. In the kneading section, the surface of the mixture of the solid / melt and / or the melt can be renewed by the kneading segment or the like, so that the melt can be evacuated more efficiently.

The screw rotation speed may be, for example, 100 to 500 rotations / minute for kneading, preferably 150 to 450 rotations / minute, and more preferably 200 to 400 rotations / minute.

For example, as shown in FIG. 1, in the mixing device 10, the kneading portion 7 is arranged between the vent port 5b arranged in the mixing zone 3 and the vent port 5c arranged in the melt zone 4. The kneading portion 7 renews the surface of the mixture and / or the melt, and the undisturbed mood can be discharged at the vent port 5c.

Next, in the spinning step, the content of the polymerization solvent having a high boiling point is reduced, the polyetherimide-based resin having a predetermined melt viscosity is weighed by a gear pump, and a predetermined amount is discharged from the spinning nozzle to spin.

The melt viscosity of the melt-kneaded polyetherimide-based resin may be, for example, 1000 to 5000 poise, more preferably 1500 to 4000 poise at ^{a shear rate of 1200 sec -1 at 390 ° C.}

The size of the spinning hole (single hole) in the spinneret is, for example, ^{about 0.01 to 0.07 mm 2} , preferably about 0.02 to 0.06 mm ² , and more preferably 0.03 to 0.05 mm ^2. It may be about. The shape of the spinning hole can be appropriately selected according to the required fiber cross-sectional shape.

The discharge amount from the spinning nozzle can be appropriately set according to the number of holes and the hole diameter of the nozzle, but may be, for example, about 35 to 300 g / min, preferably about 40 to 280 g / min.

The take-up speed (spinning speed) at that time can be appropriately set according to the nozzle hole diameter and the discharge amount, but from the viewpoint of suppressing the occurrence of molecular orientation on the spinning line, it is from 500 m / min. It is preferable to pick up in the range of 4000 m / min, more preferably 1000 m / min to 3500 m / min, and even more preferably 1500 m / min to 3000 m / min.
The discharged spun yarn can be stretched, if necessary, to obtain the polyetherimide-based fiber of the present invention.

However, the polyetherimide-based fiber of the present invention is preferably an unstretched fiber that has not been substantially stretched. The term "drawing" means a step of stretching the fibers by using a tensioning means such as a roller with respect to the cooled fibers after melt spinning, and the molten raw yarn is wound in the step of being discharged from the nozzle and then wound up. The stretching process is not included.

Since the polyetherimide-based fiber of the present invention thus obtained can reduce the content of the polymerization solvent having a high boiling point that cannot be removed by a usual melt spinning method, the content of the polymerization solvent in the fiber can be reduced. , 250 ppm or less. The content of the polymerization solvent in the fiber may be preferably 200 ppm or less, and more preferably 150 ppm or less. The lower limit of the polymerization solvent is not particularly limited, but may be, for example, about 1 ppm. The amount of the polymerization solvent is a value measured by the method described in Examples described later.

When a plurality of polymerization solvents are used, for example, the content is measured only in the high boiling point polymerization solvent (for example, dichlorobenzene (particularly o-dichlorobenzene), anisole, etc.) which is most often used in terms of molar ratio. Then, it may be judged as the content of the polymerization solvent.

As described above, the polyetherimide-based fiber of the present invention has a higher elongation at break at high temperatures than the fiber not subjected to the degassing treatment, probably because the content of the polymerization solvent having a high boiling point can be reduced. It is possible to suppress the decrease. The reason for this is not clear, but perhaps unless the content of the high boiling point polymerization solvent is reduced by a particular degassing step, the fibers will polymerize when exposed to a high temperature environment above the boiling point of the polymerization solvent. It is considered that the solvent becomes gaseous and volatilizes, and as a result, the fine structure of the fiber changes, and the breaking elongation of the fiber decreases as compared with that at room temperature.

On the other hand, in the fiber production method, when a high-level degassing treatment is performed in a melt-kneading step, the obtained fiber is a polymerization solvent even when the fiber is exposed to a high temperature environment equal to or higher than the boiling point of the polymerization solvent. It is possible to reduce the amount of gas that becomes gaseous from the fiber and volatilizes as much as possible, and as a result, it is possible to suppress the occurrence of changes in the microstructure of the fiber. It is thought that the decrease can be suppressed.

For example, the polyetherimide-based fiber may have a breaking elongation retention rate of 80% or more, preferably 82% or more, in an atmosphere of 190 ° C. with respect to an atmosphere of room temperature (20 ° C.). More preferably, it may be 85% or more. The upper limit is not particularly limited, but may be 110% or less, for example.

Further, the fineness of the single fiber of the polyetherimide-based fiber of the present invention can be appropriately set depending on the intended purpose, for example, 0.1 to 15 dtex, preferably 0.1 to 10 dtex, more preferably 0.2. It may be up to 9 dtex, more preferably 0.3 to 8 dtex, and particularly preferably 0.3 to 5 dtex.

Further, the total fineness of the multifilament of the polyetherimide-based fiber of the present invention may be, for example, 50 to 5000 dtex, preferably 100 to 3000 dtex, and more preferably 200 to 2000 dtex.

The polyetherimide-based fiber may be either a continuous fiber or a non-continuous fiber, and when it is a non-continuous fiber, for example, the average fiber length of the single fiber is 0.5 to 60 mm, preferably 5 to 50 mm. It may be a short fiber. The cross-sectional shape of the fiber is not particularly limited, and may be circular, hollow, flat, polygonal, T-shaped, L-shaped, I-shaped, cross-shaped, multi-leaf-shaped, star-shaped, or other irregular cross-section. It doesn't matter.

Polyetherimide-based fibers show excellent heat resistance in all fiber forms such as staple fibers, shortcut fibers, filament yarns, spun yarns, cords, ropes, and fabrics, so they can be used in a wide variety of applications. Further, in the above fiber form, the polyetherimide-based fiber of the present invention may be combined with other fibers, if necessary.

(Products containing polyetherimide-based fibers)
Polyetherimide-based fibers are used in many applications such as industrial materials, electrical and electronic fields, agricultural materials, apparel, optical materials, aircraft, automobiles, and ships as various textile products used at high temperatures. It can be used extremely effectively, and is useful in many applications such as insulating paper, work clothes, fireproof clothes, seat cushioning materials, and hook-and-loop fasteners.

The polyetherimide-based fiber of the present invention can suppress a decrease in breaking elongation of the fiber at a high temperature (for example, 150 ° C. or higher and 200 ° C. or lower) as compared with a fiber not subjected to degassing treatment. Is. Therefore, various textile products can be designed on the premise that they have a breaking elongation similar to that at room temperature, which is advantageous.

(binder)
The polyetherimide-based fiber may be used in combination with a binder (for example, a binder fiber), if necessary.

For example, examples of the binder include polyolefin fibers, polyamide fibers, polyester fibers, and liquid substances such as powders and emulsions of these resins, of which polyester fibers are preferable.

(Reinforcing fiber)
The reinforcing fibers used in the present invention are not particularly limited as long as the effects of the present invention are not impaired, and may be organic fibers or inorganic fibers, or may be used alone or in combination of two or more. May be good. For example, examples of the inorganic fiber include glass fiber, carbon fiber, silicon carbide fiber, alumina fiber, ceramic fiber, genbuiwa fiber, and various metal fibers (for example, gold, silver, copper, iron, nickel, titanium, stainless steel, etc.). Examples of organic fibers include total aromatic polyester fibers, polyphenylene sulfide fibers, para-aramid fibers, polysulphonamide fibers, phenol resin fibers, total aromatic polyimide fibers, and fluorine fibers. can do. The organic fiber may be a stretched fiber that has been stretched, if necessary.

Of these reinforcing fibers, carbon fibers, glass fibers, all-aromatic polyester fibers, and para-aramid fibers are preferably used from the viewpoints of mechanical properties, flame retardancy, heat resistance, and availability.

The fineness of the single fiber of the reinforcing fiber can be appropriately set according to the fineness of the polyetherimide-based fiber, and may be, for example, 0.01 to 10 dtex, preferably 0.1 to 8 dtex, and more preferably 0.1 to 8 dtex. It may be 1 to 6 dtex.

The ratio of the single fiber fineness of the polyetherimide-based fiber to the single fiber fineness of the reinforcing fiber (PEI fiber / reinforcing fiber) is, for example, about 10/90 to 90/10, more preferably about 30/70 to 70/30. It may be.

Further, the total fineness of the multifilament of the reinforcing fiber may be, for example, 50 to 5000 dtex, preferably 100 to 3000 dtex, and more preferably 200 to 2000 dtex.

The reinforcing fiber may be either a continuous fiber or a non-continuous fiber, and when the reinforcing fiber is a non-continuous fiber, the average fiber length of the single fiber is, for example, 1 to 40 mm, preferably 5 to 35 mm, and more preferably 10 to. It may be a short fiber having a thickness of 30 mm.
The cross-sectional shape of the fiber is not particularly limited, and may be circular, hollow, flat, polygonal, T-shaped, L-shaped, I-shaped, cross-shaped, multi-leaf-shaped, star-shaped, or other irregular cross-section. It doesn't matter.

(Fiber products)
The textile product composed of polyetherimide-based fibers may be composed of a woven or knitted fabric, a non-woven fabric, or the like. The textile product may be formed of a polyetherimide-based fiber alone, or may be used in combination with other fibers, if necessary.

For example, a woven fabric may include a polyetherimide-based fiber or a mixed fiber yarn thereof as a warp and / or a weft yarn, and a knitting may include a polyetherimide-based fiber or a mixed fiber yarn thereof as a knitting yarn. May be good. The non-woven fabric may contain polyetherimide-based fibers and may be integrated by chemical or physical bonding. For example, the non-woven fabric to which the polyetherimide-based fibers are adhered by a binder (for example, binder fibers). It may be a non-woven fabric to which a polyetherimide-based fiber and a reinforcing fiber are adhered by a binder (for example, a binder fiber).

The method for producing the non-woven fabric of the present invention is not particularly limited, and examples thereof include known or conventional non-woven fabric manufacturing methods such as spunlace non-woven fabric, needle punched non-woven fabric, steam jet non-woven fabric, dry papermaking method, and wet papermaking method. Of these, the wet papermaking method is preferable from the viewpoint of production efficiency and uniform dispersion of the reinforcing fibers in the non-woven fabric.
For example, in the wet papermaking method, an aqueous slurry containing at least the polyetherimide-based fiber, the reinforcing fiber and, if necessary, a binder (for example, a polyester-based binder fiber) is prepared, and then this slurry is subjected to a normal papermaking process. Just do it.

In the papermaking process, a drying process under heating is performed to dry the slurry. The heating temperature at this time is, for example, equal to or higher than the softening point of the polyester-based binder fiber, and in this drying step, the polyester-based binder fiber in the slurry fuses the polyetherimide-based fiber and the reinforcing fiber, and paper or web. A non-woven fabric having a shape can be formed.
Further, when producing a non-woven fabric, in order to improve the adhesiveness of the polyester-based binder fiber, it is preferable to further perform a thermal bond process such as hot pressing and through air bond on the once obtained web. Further, in order to improve the uniformity and pressure-bonding property of the non-woven fabric, a binder may be applied by spray-drying.

The basis weight of the textile product of the present invention can be appropriately set depending on the presence or absence of a reinforcing material, for example, ^{preferably 5 to 5000 g / m 2} , more preferably 10 to 2000 g / m ² , and even more preferably. May be 20 to 500 g / m ² .

The textile product of the present invention may have an appropriate thickness depending on the application, from thick to thin. For example, in the case of a thin textile product, the thickness may be, for example, 200 μm or less, preferably 30 to 150 μm, and more preferably 50 to 120 μm.

(Composite material)
The composite material of the present invention is not particularly limited as long as it contains a melt of a polyetherimide-based fiber as a matrix, and may be a composite material containing various materials. For example, the composite material of the present invention may be provided as a matrix by melting the polyetherimide-based fibers in the textile product.

The polyetherimide-based fiber of the present invention can suppress a decrease in the breaking elongation of the fiber at a high temperature as compared with a fiber not subjected to the degassing treatment, and thus can be used as a matrix material for forming a composite material. Is also useful. In particular, in forming a composite having a non-planar shape, the polyetherimide-based fiber of the present invention is useful as a matrix material even if a non-planar portion such as a step or an angular portion is present.

For example, when fibers are applied to a non-planar portion such as a step or a square portion to form a matrix, the fibers are stretched by a predetermined tension in the non-planar portion. As a result, if the stretched fibers break during the heating process, the portions of the composite may cause defects such as wrinkles and holes.

On the other hand, in the polyetherimide-based fiber of the present invention, the elongation at break retention rate at high temperature is good, so that the elongation at break changes under heating even if a non-planar portion is present. Can be suppressed. Therefore, the composite material of the present invention is advantageous in that it can be easily molded into a complicated shape such as a seat or tank of various vehicles and an air duct (particularly an air duct for an aircraft).

When the reinforcing fiber is contained in the composite material, the composite material preferably comprises a melt of a polyetherimide-based fiber as a matrix, and the reinforcing fiber is contained in the matrix, and more preferably, the reinforcing fiber is used. , Preferably dispersed in the matrix.

For example, the composite material may be provided with melting of the polyetherimide-based fiber as a matrix by laminating one or a plurality of fabrics containing the polyetherimide-based fiber and then heating the composite material.

The composite material of the present invention may be formed, for example, by heat molding in which the polyetherimide-based fiber is heated above the flow start temperature. Here, the flow start temperature means the melting point of the crystalline resin and the glass transition temperature of the amorphous resin.

The heat molding method is not particularly limited, and for example, various molding methods by heat compression, particularly compression molding such as stampable molding, pressure molding, vacuum pressure molding, and GMT molding are preferably used. The molding temperature at that time may be set according to the flow start temperature and the decomposition temperature of the polyetherimide-based fiber to be used.

For example, when the polyetherimide-based fiber is crystalline, the molding temperature is preferably in the range of the melting point of the polyetherimide-based fiber or higher and (melting point +100) ° C. or lower. When the polyetherimide-based fiber is amorphous, the molding temperature is preferably in the range of the glass transition temperature of the polyetherimide-based fiber or more and (glass transition temperature +200) ° C. or less. If necessary, it can be preheated with an IR heater or the like before heat molding.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the present Examples.

[Content of polymerization solvent (ppm)]
The content of the polymerization solvent was measured using thermal decomposition GC / MS. Measurements were performed using a GC / MS apparatus "7890GC / 5977MSD" manufactured by Agilent Technologies and a thermal decomposition apparatus "Single Shot Pyrolyzer PY-3030S" manufactured by Frontier Lab.

(Device / measurement conditions)
・ Pyrolysis equipment conditions Pyrolysis furnace: 300 ° C, interface: 280 ° C
-GC / MS device Column: UA-5MS (30m-0.25mm-0.25μm)
Oven: 50 ° C (hold for 1 minute) → 20 ° C / min → 290 ° C (hold for 17 minutes)
Injection port: 280 ° C, split injection (20: 1)
Ionization: EI +
Detection method: SIM method (m / z = 146)
-Sample fiber: 0.500 mg
First, a fiber sample was collected in a pyrolysis sample cup (0.500 mg), and the sample was set in a pyrolysis GC / MS pyrolysis furnace. After 3 minutes, the sample cup was dropped into a pyrolysis furnace, GC / MS measurement was started, and ions at m / z = 146 were measured. After the measurement was completed, the o-dichlorobenzene content (ppm) was calculated from the peak area value. As a sample for the calibration curve, 25 ppm, 50 ppm, and 100 ppm o-dichlorobenzene solutions were prepared with an acetone solution and measured.

[Single fiber fineness (dtex)]
100 fibers were randomly extracted from the multifilament, the fineness of each single fiber was measured, and the average value was calculated and used as the single fiber fineness.

[Fiber length (mm)]
100 fibers were randomly extracted from the cut yarn, the fiber lengths of each were measured, and the average value was calculated and used as the fiber length.

[Metsuke of textile products (g / m ² )]
The measurement was performed according to the JIS L 1913 test method, and the average value of n = 3 was adopted.

[Example 1]
(1) A polyetherimide-based resin (“Ultem 9011” manufactured by Savik Innovative Plastics Co., Ltd.) was prepared and dried at 150 ° C. for 12 hours.
(2) The resin of (1) above is put into a twin-screw extruder and kneaded with a screw while melting at 390 ° C. One vent port is provided in each of the solid zone, the mixing zone, and the melt zone, and venting is performed. The mouth was kept at about 20 mmHg and degassed. Further, in the mixing zone and the melt zone, a kneading segment is provided at the screw segment position between these vent positions, and the spinning segment is discharged from the round hole nozzle under the conditions of a spinning speed of 2000 m / min and a discharge rate of 50 g / min, and 220 dtex / min. A multifilament of 100 filaments was obtained. Table 1 shows the results of measuring various physical properties of the obtained fibers.

[Example 2]
(1) A polyetherimide-based resin (“Ultem 9011” manufactured by Savik Innovative Plastics Co., Ltd.) was prepared and dried at 150 ° C. for 12 hours.
(2) The resin of (1) is put into a twin-screw extruder and kneaded with a screw while melting at 390 ° C. There are one vent port in each of the solid zone and the mixing zone, and two in the melt zone. The vent port was maintained at about 20 mmHg and degassed, and the mixture was discharged from a round hole nozzle under the conditions of a spinning speed of 2000 m / min and a discharge rate of 50 g / min to obtain a multifilament of 250 dtex / 100 filaments. Table 1 shows the results of measuring various physical properties of the obtained fibers.

[Example 3]
(1) A polyetherimide-based resin (“Ultem 9011” manufactured by Savik Innovative Plastics Co., Ltd.) was prepared and dried at 150 ° C. for 12 hours.
(2) The resin of (1) is put into a twin-screw extruder and kneaded with a screw while melting at 390 ° C. One vent port is provided in each of the solid zone, the mixing zone, and the melt zone, and the vent port is provided. Was degassed at about 20 mmHg and discharged from a round hole nozzle under the conditions of a spinning speed of 2000 m / min and a discharge rate of 50 g / min to obtain a multifilament of 250 dtex / 100 filaments. Table 1 shows the results of measuring various physical properties of the obtained fibers.

[Example 4]
(1) A polyetherimide-based resin (“Ultem 9011” manufactured by Savik Innovative Plastics Co., Ltd.) was prepared and dried at 150 ° C. for 12 hours.
(2) The resin of (1) is put into a twin-screw extruder and kneaded with a screw while melting at 390 ° C. One vent port is provided in each of the solid zone, the mixing zone, and the melt zone, and the vent port is provided. Was degassed at about 35 mmHg and discharged from a round hole nozzle under the conditions of a spinning speed of 2000 m / min and a discharge rate of 50 g / min to obtain a multifilament of 250 dtex / 100 filaments. Table 1 shows the results of measuring various physical properties of the obtained fibers.

[Example 5]
(1) A polyetherimide-based resin (“Ultem 9011” manufactured by Savik Innovative Plastics Co., Ltd.) was prepared and dried at 150 ° C. for 12 hours.
(2) The resin of (1) is put into a twin-screw extruder and kneaded with a screw while melting at 390 ° C. One vent port is provided in each of the solid zone and the melt zone, and the vent port is about 35 mmHg. The mixture was degassed at a speed of 2000 m / min and discharged from a round hole nozzle under the conditions of a spinning speed of 2000 m / min and a discharge rate of 50 g / min to obtain a multifilament of 250 dtex / 100 filaments. Table 1 shows the results of measuring various physical properties of the obtained fibers.

[Comparative Example 1]
(1) A polyetherimide-based resin (“Ultem 9011” manufactured by Savik Innovative Plastics Co., Ltd.) was prepared and dried at 150 ° C. for 12 hours.
(2) The polymer of (1) above is put into a twin-screw extruder and kneaded with a screw while melting at 390 ° C., one vent port is provided in each of the solid zone and the mixing zone, and the vent port is about 80 mmHg. The degassed product was discharged from a round hole nozzle under the conditions of a spinning speed of 2000 m / min and a discharge rate of 50 g / min to obtain a 250 dtex / 100 filament multifilament. Table 1 shows the results of measuring various physical properties of the obtained fibers.

[Comparative Example 2]
(1) A polyetherimide-based resin (“Ultem 9011” manufactured by Savik Innovative Plastics Co., Ltd.) was prepared and dried at 150 ° C. for 12 hours.
(2) The polymer of (1) above is put into a twin-screw extruder and kneaded with a screw while melting at 390 ° C. One vent port is provided in each of the solid zone and the mixing zone, and the vent port is about 80 mmHg. I kept it and degassed. Further, a kneading segment is provided at the screw segment position on the downstream side (resin advancing side) of the vent port of the mixing zone, and the spinning segment is discharged from the round hole nozzle under the conditions of a spinning speed of 2000 m / min and a discharge rate of 50 g / min, and 250 dtex. A multifilament of / 100 filaments was obtained. Table 1 shows the results of measuring various physical properties of the obtained fibers.

[Comparative Example 3]
(1) A polyetherimide-based resin (“Ultem 9011” manufactured by Savik Innovative Plastics Co., Ltd.) was prepared and dried at 150 ° C. for 12 hours.
(2) The polymer of (1) above is put into a twin-screw extruder, kneaded with a screw while melting at 390 ° C., one vent port is provided in each of the solid zone and the mixing zone, and the vent port is about 35 mmHg. The degassed product was discharged from a round hole nozzle under the conditions of a spinning speed of 2000 m / min and a discharge rate of 50 g / min to obtain a 250 dtex / 100 filament multifilament. Table 1 shows the results of measuring various physical properties of the obtained fibers.

[Comparative Example 4]
(1) A polyetherimide-based resin (“Ultem 9011” manufactured by Savik Innovative Plastics Co., Ltd.) was prepared and dried at 150 ° C. for 12 hours.
(2) The polymer of (1) above is put into a twin-screw extruder and kneaded with a screw while melting at 390 ° C. One vent port is provided in each of the solid zone, the mixing zone, and the melt zone, and venting is performed. A degassed product having a mouth kept at about 80 mmHg was discharged from a round hole nozzle under the conditions of a spinning speed of 2000 m / min and a discharge rate of 50 g / min to obtain a 250 dtex / 100 filament multifilament. Table 1 shows the results of measuring various physical properties of the obtained fibers.

[Comparative Example 5]
(1) A polyetherimide-based resin (“Ultem 9011” manufactured by Savik Innovative Plastics Co., Ltd.) was prepared and dried at 150 ° C. for 12 hours.
(2) The polymer of (1) above is put into a twin-screw extruder, kneaded with a screw while melting at 390 ° C., vent ports are provided in a mixing zone and a melt zone, and the vent port is kept at about 80 mmHg for removal. What was noticed was discharged from a round hole nozzle under the conditions of a spinning speed of 2000 m / min and a discharge rate of 50 g / min to obtain a multifilament of 250 dtex / 100 filaments. Table 1 shows the results of measuring various physical properties of the obtained fibers.

As shown in Table 1, when the content (residual solvent amount) of the polymerization solvent present in the fiber decreases, the elongation at break retention rate increases as a whole. In Examples 1 to 5, since the vent ports are provided in the solid zone and the melt zone, the content of the polymerization solvent (residual solvent amount) present in the fiber is reduced, and the elongation at break retention rate is increased. It can be 80% or more.

More specifically, when Example 3, Example 4, and Comparative Example 4 are compared, it can be seen that the lower the pressure at the vent port, the more the residual solvent amount can be reduced. Further, comparing Example 2 and Example 3, it can be seen that the larger the number of vent ports, the more the amount of residual solvent can be reduced. Furthermore, when Example 1 and Example 3 are compared, it can be seen that the amount of residual solvent can be reduced by 70 ppm by providing a kneading portion and performing kneading between vents. Comparing Example 5 and Comparative Example 3, it can be seen that even if the number of vent ports is the same, if the positions are different, the amount of residual solvent also changes.

On the other hand, in Comparative Examples 1 to 5, the content of the polymerization solvent (residual solvent amount) present in the fiber is reduced because the vent port cannot be arranged appropriately or the pressure of the vent port is not sufficiently low. As a result, the elongation at break retention rate is lower than that of the examples.

More specifically, in Comparative Example 1, although vent ports are provided in the solid zone and the mixing zone, the vent ports are not arranged in the melt zone, and the vacuum degassing of the vent ports is insufficient. Therefore, it is difficult to reduce the amount of residual solvent.

Further, when Comparative Example 1 and Comparative Example 2 are compared, in Comparative Example 2, although the kneading portion is provided, the vent port is not arranged on the downstream side of the kneading portion, and the vacuum of the vent port is further increased. Since deaeration is also insufficient, it can be seen that there is almost no effect of reducing the amount of residual solvent.

Comparing Comparative Example 1 and Comparative Example 3, it can be seen that the amount of residual solvent cannot be reduced to 250 ppm or less simply by reducing the pressure at the vent port. Comparing Comparative Example 1 or 5 with Comparative Example 4, it can be seen that the amount of residual solvent cannot be reduced to 250 ppm or less simply by increasing the number of vent ports.

The polyetherimide-based fiber of the present invention can suppress a decrease in breaking elongation of the fiber at a high temperature (for example, 150 ° C. or higher and 200 ° C. or lower) as compared with a fiber that is not degassed. It is possible. Therefore, taking advantage of these characteristics of polyetherimide-based fibers, as textile products used under various high temperatures, industrial materials field, electrical / electronic field, civil engineering / construction field, agricultural material field, apparel field, optical material field, etc. It can be used extremely effectively in many applications such as aircraft, automobiles, ships, and medical materials. For example, it can be used in many applications such as insulating paper, work clothes, fireproof clothing, seat cushioning materials, and hook-and-loop fasteners. It is useful for.

Furthermore, the composite material obtained by melting polyetherimide-based fibers can be freely designed in shape according to the purpose as various molded products, and can be freely designed in the fields of industrial materials, electrical / electronic fields, civil engineering / construction. It can be used extremely effectively in many applications such as fields, aircraft / automobile / railway / ship fields, agricultural materials fields, optical materials fields, medical materials fields, etc. For example, seats, tanks, and air ducts for various vehicles. It is useful as a composite material for (especially air ducts for aircraft).

As described above, preferred embodiments of the present invention have been described, but those skilled in the art can make various additions, changes or deletions as long as they do not deviate from the gist of the present invention by looking at the present specification. , Such are also included within the scope of the present invention.

1 ... Resin tip 2 ... Solid zone 3 ... Mixing zone 4 ...

Melt zone

5a, 5b, 5c ... Vent port 6 ... Screw 7 ... Kneading part 10 ...・ Mixing device

Claims

A polyetherimide-based fiber made of a polyetherimide-based resin containing a polymerization solvent having a boiling point of 100 ° C. or higher, wherein the content of the polymerization solvent in the fiber is 250 ppm or less.
The polyetherimide-based fiber according to claim 1, wherein the breaking elongation retention rate in a 190 ° C. atmosphere with respect to a room temperature (20 ° C.) atmosphere is 80% or more.
The polyetherimide-based fiber according to claim 1 or 2, wherein the polymerization solvent is dichlorobenzene, dichlorotoluene, trichlorobenzene, diphenylsulfone, monoalkoxybenzene, dialkoxybenzene, diphenyl ether, dimethylformamide, dimethylacetamide, dimethyl. A polyetherimide-based fiber, which is at least one selected from the group consisting of sulfoxide and N-methylpyrrolidinone.
The method for producing a polyetherimide-based fiber according to any one of claims 1 to 3.
It includes a step of melt-kneading a polyetherimide-based resin containing a polymerization solvent having a boiling point of 100 ° C. or higher, and a step of spinning.
In the melt-kneading step, the polyetherimide-based resin passes through a solid zone, a mixed zone of a solid and a melt, and a melt zone.
Vent openings are provided, at least in the solid zone and the melt zone.
A manufacturing method in which vacuum degassing is performed at a pressure of 0 to 50 mmHg at the vent port, at least in the melt zone.
The method for producing a polyetherimide-based fiber according to claim 4, wherein vent ports are arranged in a solid zone, a mixing zone, and a melt zone.
The method for producing a polyetherimide-based fiber according to claim 4 or 5, wherein at least one kneading portion is arranged at a position between the vent openings.
A textile product composed of the polyetherimide-based fiber according to any one of claims 1 to 3.
A composite material comprising the melt of the polyetherimide-based fiber according to any one of claims 1 to 3 as a matrix.