KR101612916B1 - Cyclic olefin resin fiber, and non-woven cyclic olefin resin fabric - Google Patents

Abstract

Ultrafine cyclic olefin based resin fibers, and cyclic olefin based resin nonwoven fabric. A polymer solution containing a volatile solvent and a cyclic olefin resin is spun by an electrostatic spinning method. The volatile solvent to be used preferably contains at least one solvent selected from the group consisting of chloroform, toluene, xylene, cyclohexane and decalin. In addition, by using a cyclic olefin resin having a glass transition point of 160 캜 or higher, it is possible to impart high heat resistance to the cyclic olefin resin fiber.

Description

CYCLIC OLEFIN RESIN FIBER, AND NON-WOVEN CYCLIC OLEFIN RESIN FABRIC}

The present invention relates to a cyclic olefin resin fiber and a cyclic olefin resin nonwoven fabric obtained by an electrostatic spinning method.

When the fiber diameter of the fibers constituting the nonwoven fabric is reduced, various performances such as separation performance, liquid holding performance, wiping performance, hiding performance, insulation performance, and flexibility are excellent. For this reason, it is required to further reduce the fiber diameter of the fibers constituting the nonwoven fabric.

As a method for producing such a nonwoven fabric made of fibers having a small fiber diameter, electrostatic spinning can be mentioned. In the electrostatic spinning method, a high voltage is applied between a tip of a nozzle containing a polymer solution and a collector substrate, the polymer solution is ultrafine due to the electrostatic repulsion force, the volatile solvent contained in the polymer solution evaporates, Ultrafine fibers and nonwoven fabrics. Examples of the resin included in the polymer solution include polypropylene resin and polyethylene resin.

In recent years, however, the development of organic materials in the fields of electronics, environment and energy has been remarkable, and the performance required for organic materials has been variously found in heat resistance, dimensional stability, and electrical characteristics. Various processing forms are also required in accordance with the demand for miniaturization and weight reduction of parts. Among them, the cyclic olefin resin has attracted attention as a material which is amorphous and excellent in transparency, heat resistance and electrical properties at high frequencies. Therefore, when the cyclic olefin resin is used, the performance of the nonwoven fabric made of the ultrafine fibers and the ultrafine fibers can be improved.

However, there are no reports of actually producing cyclic olefin resin fibers and cyclic olefin resin nonwoven fabrics having a fiber diameter of nano order by electrospinning. Further, the practical use of the cyclic olefin-based resin as a fiber has not progressed.

As the cyclic olefin-based resin fiber, for example, there is a fiber having a fiber diameter of 10 mu m to 100 mu m obtained by melt spinning (Patent Document 1: JP-A-2005-171404). However, no nonwoven fabric composed of ultrafine fibers and microfine fibers has been obtained.

1. Japanese Patent Application Laid-Open No. 2005-171404

As described above, the cyclic olefin-based resin has excellent electrical properties and heat resistance. For this reason, the production of ultrafine cyclic olefin based resin fibers and the nonwoven fabric made of the ultrafine fibers are expanded, and the development of various applications is expanded. Therefore, ultrafine cyclic olefin based resin fibers and nonwoven fabrics made of the ultrafine fibers are required.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and an object of the present invention is to provide an ultrafine cycloolefin resin fiber and a cyclic olefin resin nonwoven fabric.

DISCLOSURE OF THE INVENTION The present inventors have conducted intensive studies in order to solve the above problems. As a result, a polymer solution containing a volatile solvent and a cycloolefin resin was emulsified by electrospinning to obtain an aggregate of cyclic olefin resin fibers and cyclic olefin resin fibers having an average fiber diameter of 0.01 mu m to 10 mu m And have reached the present invention. More specifically, the present invention provides the following.

 (1) A cyclic olefin based resin fiber obtained by spinning a polymer solution having an average fiber diameter of 0.01 탆 to 10 탆 and containing a volatile solvent and a cyclic olefin resin by an electrospinning method.

 (2) The cyclic olefin based resin fiber according to (1), wherein the average fiber diameter is 0.1 占 퐉 to 0.5 占 퐉.

 (3) The cycloolefin resin fiber according to (1) or (2), wherein the volatile solvent contains at least one solvent selected from the group consisting of chloroform, toluene, xylene, cyclohexane and decalin.

 (4) The cycloolefin-based resin fiber according to any one of (1) to (3), wherein the cyclic olefin-based resin has a glass transition point of 160 ° C or more.

(5) A cyclic olefin resin nonwoven fabric comprising the cyclic olefin based resin fiber according to any one of (1) to (4).

According to the present invention, a polymer solution containing a volatile solvent and a cyclic olefin resin is emulsified by electrospinning to obtain an aggregate of the ultrafine cyclic olefin resin fiber and the cyclic olefin resin fiber.

1 is a schematic view showing an example of an electrostatic spinning device.

Hereinafter, one embodiment of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, but can be appropriately modified within the scope of the object of the present invention.

The cyclic olefin resin fibers and the cyclic olefin resin nonwoven fabric of the present invention are characterized by being obtained by spinning a polymer solution containing a volatile solvent and a cyclic olefin resin by electrospinning.

The polymer solution used in the present invention includes a cyclic olefin resin and a volatile solvent. The present invention is characterized by using a cyclic olefin resin.

<Cyclic Olefin Resin>

The cyclic olefin resin used in the present invention contains a cyclic olefin component as a copolymerization component and is not particularly limited as long as it is a polyolefin-based resin containing a cyclic olefin component in its main chain. Examples thereof include addition polymers of cyclic olefins or hydrogenated products thereof, addition copolymers of cyclic olefins and? -Olefins or hydrogenated products thereof.

The cyclic olefin resin (A) containing the cyclic olefin component as the copolymerization component used in the present invention includes those obtained by grafting and / or copolymerizing an unsaturated compound having a polar group further in the polymer.

Examples of the polar group include a carboxyl group, an acid anhydride group, an epoxy group, an amide group, an ester group and a hydroxyl group. Examples of the unsaturated compound having a polar group include (meth) acrylic acid, maleic acid, maleic anhydride, (Meth) acrylate, glycidyl (meth) acrylate, alkyl (meth) acrylate (having 1 to 10 carbon atoms) ester, alkyl acrylate (having 1 to 10 carbon atoms) Ethyl and the like.

In the present invention, an addition copolymer of a cyclic olefin and an? -Olefin or a hydrogenated product thereof can be preferably used.

A commercially available resin can be used as the cyclic olefin resin (A) containing the cyclic olefin component as a copolymerization component used in the present invention. Examples of the commercially available cycloolefin resin (A) include TOPAS (registered trademark) (TOPAS Advanced Polymers), APEL (registered trademark) (Mitsui Chemicals), Zeonex (registered trademark) ), Zeonoa (registered trademark) (manufactured by Nippon Zeon Co., Ltd.), ATON (registered trademark) (manufactured by JSR Corporation), and the like.

The addition copolymer of the cyclic olefin and the? -Olefin preferably used in the present invention is not particularly limited. Particularly preferred examples thereof include copolymers comprising [1] an? -Olefin having 2 to 20 carbon atoms and [2] a cyclic olefin having the following general formula (I).

(Wherein R ¹ to R ¹² may be the same or different and each is selected from the group consisting of a hydrogen atom, a halogen atom and a hydrocarbon group,

R ⁹ and R ¹⁰ , and R ¹¹ and R ¹² may be monovalent to form a divalent hydrocarbon group,

R ⁹ or R ¹⁰ and R ¹¹ or R ¹² may form a ring with each other.

N represents 0 or a positive integer,

When n is 2 or more, R ⁵ to R ⁸ may be the same or different from each other in each repeating unit.)

[1]? -Olefin component having 2 to 20 carbon atoms]

The? -Olefin having 2 to 20 carbon atoms which is a copolymerization component of the addition polymer of the cyclic olefin component preferably used in the present invention and other copolymerizable components such as ethylene is not particularly limited. For example, the same as in Japanese Patent Application Laid-Open No. 2007-302722. These? -Olefin components may be used singly or in combination of two or more. Of these, ethylene alone is most preferable

[(2) Cyclic Olefin Component Represented by Formula (I)]

The cyclic olefin component represented by the formula (I) which is a copolymerizable component in the addition polymer of the cyclic olefin component preferably used in the present invention and other copolymerizable components such as ethylene will be described.

R ¹ to R ¹² in the formula (I) may be the same or different and are each selected from the group consisting of a hydrogen atom, a halogen atom and a hydrocarbon group.

Specific examples of R ¹ to R ⁸ include, for example, a hydrogen atom; Halogen atoms such as fluorine, chlorine and bromine; And a lower alkyl group such as a methyl group, an ethyl group, a propyl group, and a butyl group, and they may be different from each other, may be partially different, and may be all the same.

Specific examples of R ⁹ to R ¹² include, for example, a hydrogen atom; Halogen atoms such as fluorine, chlorine and bromine; An alkyl group such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, hexyl group and stearyl group; A cycloalkyl group such as a cyclohexyl group; Substituted or unsubstituted aromatic hydrocarbon groups such as a phenyl group, a trityl group, an ethylphenyl group, an isopropylphenyl group, a naphthyl group, and an anthryl group; A benzyl group, a phenethyl group, and an aralkyl group in which the alkyl group is substituted with an aryl group, and they may be different from each other, may be partially different, and may be all the same.

Specific examples of the case where R ⁹ and R ¹⁰ , or R ¹¹ and R ¹² are combined to form a bivalent hydrocarbon group include alkylidene groups such as ethylidene group, propylidene group and isopropylidene group, .

The ring formed when R ⁹ or R ¹⁰ and R ¹¹ or R ¹² form a ring with each other may be a monocyclic ring, a polycyclic ring, a polycyclic ring having a bridge, or a ring having a double bond, Or a combination of rings. These rings may have a substituent such as a methyl group.

Specific examples of the cyclic olefin component represented by the formula (I) include the same ones as in JP-A-2007-302722.

These cyclic olefin components may be used singly or in combination of two or more kinds. Of these, bicyclo [2.2.1] hept-2-en (synonym: norbornene) is preferably used alone.

The glass transition point of the cyclic olefin based resin is preferably 160 ° C or higher. The glass transition point (Tg) is a value measured by a DSC method (method described in JIS K7121) at a heating rate of 10 캜 / min. By using a cyclic olefin resin having a glass transition point of 160 캜 or higher, it is possible to impart sufficient heat resistance to the cyclic olefin resin fiber and the cyclic olefin resin nonwoven fabric.

In order to produce the ultrafine cyclic olefin based resin fiber by the electrospinning method, it is necessary to adjust the viscosity of the polymer solution to a viscosity suitable for electrostatic spinning. As described later, since the preferable range of the polymer concentration of the polymer solution is fixed, it is necessary to have a desired viscosity within the range of the polymer concentration. The content of the cyclic olefin component in the cyclic olefin resin is in the range of 60% by mass to 90% by mass, since it is easy to realize the desired viscosity.

The method of polymerizing the [1]? -Olefin having 2 to 20 carbon atoms with the cyclic olefin represented by the formula (2) and the hydrogenation of the obtained polymer are not particularly limited and may be carried out according to a known method . May be random copolymerization or block copolymerization, but is preferably a random copolymer.

The polymerization catalyst to be used is not particularly limited, and can be obtained by a known method using a conventionally known catalyst such as a Ziegler-Natta catalyst, a Metacis catalyst, a metallocene catalyst or the like. The addition copolymer of the cyclic olefin and the? -Olefin, which is preferably used in the present invention, or the hydrogenated product thereof is preferably produced using a metallocene catalyst.

As the metathesis catalyst, a known molybdenum or tungsten-based metathesis catalyst as a catalyst for ring-opening polymerization of cycloolefins (for example, JP-A-58-127728, JP-A-58-129013 ). The polymer obtained by the metathesis catalyst can be obtained by using an inorganic carrier-carrying transition metal catalyst or the like, and by hydrogenating at least 90% of the double bond in the main chain and 98% or more of the carbon-carbon double bond in the aromatic ring in the side chain .

[Other copolymerizable components]

The cyclic olefin resin (A) may contain, in addition to the above-mentioned [1] -olefin component having 2 to 20 carbon atoms and [2] the cyclic olefin component represented by the formula (I) , And may contain other copolymerizable unsaturated monomer components as required.

Examples of the unsaturated monomer that can be optionally copolymerized include, but are not limited to, a hydrocarbon-based monomer containing two or more carbon-carbon double bonds in one molecule. Specific examples of hydrocarbon-based monomers containing two or more carbon-carbon double bonds in one molecule are the same as those in Japanese Patent Application Laid-Open No. 2007-302722.

 [Other ingredients]

The cyclic olefin-based resin used in the present invention may contain other resins to the extent that the effects of the present invention are not impaired, and thus the cyclic olefin-based resin composition may be used. Compositions to which desired characteristics are imparted by adding additives such as pigments such as nucleating agent, carbon black and inorganic calcining pigment, antioxidants, stabilizers, plasticizers, lubricants, mold release agents and flame retardants are also added within the scope of not hindering the effects of the invention Based resin to be used in the present invention.

 [Physical Properties of Cyclic Olefin Resin]

The weight average molecular weight of the cyclic olefin based resin measured by the method described in the embodiment is preferably 50,000 to 200,000. For filamentization by the electrospinning method, polymers must be entangled with each other in the polymer solution. When the weight average molecular weight of the cyclic olefin resin is within the above range, the polymers are sufficiently intertwined with each other to easily obtain the ultraclea cyclic olefin resin fiber . Also, from the viewpoint that the polymer solution exhibits a viscosity suitable for spinning by electrospinning, the weight average molecular weight is preferably in the above range.

A melt viscosity measured at 260 占 폚 and a shear rate of 1216 / sec in accordance with ISO 11443 of a cycloolefin resin is preferably in the range of 50 to 400 Pa 占 퐏 in the range of the polymer concentration to be described below in order to adjust the viscosity of the polymer solution to a desired range. s. &lt; / RTI &gt;

<Volatile Solvent>

The volatile solvent is not particularly limited as long as it dissolves the cyclic olefin resin. The volatile solvent may be mixed for two or more solvents. The cycloolefin resin is liable to be dissolved in a solvent such as chloroform, toluene, xylene, cyclohexane, decalin and the like. The cyclic olefin resin is likewise liable to be dissolved in these volatile solvents.

As described above, the cyclic olefin resin is liable to be dissolved in various solvents. As a result, it is also a feature of the cyclic olefin based resin fiber of the present invention that it is easy to conduct electrostatic radiation. Conventionally, polyethylene and polypropylene can be cited as main resins used in the electrospinning, but these resins have a problem that they can not be dissolved unless they are heat (heat) solvents. In the cyclic olefin based resin fiber of the present invention, there is no such a problem.

Especially, when the ultrafine fibers are produced by the electrostatic spinning method, the evaporation rate of the volatile solvent becomes important property. As a solution for the problem of the evaporation rate of the volatile solvent, a method of adjusting the shape of the nozzle, a method of using a mixed solvent, a method of adjusting the atmosphere temperature and humidity, and the like can be given. Particularly, a solution using a mixed solvent is simple. In order to implement a solution using a mixed solvent, it is preferable that the resin composition is dissolved in various solvents. The cycloolefin resin used in the present invention dissolves in various volatile solvents as described above and is easily dissolved in a mixed solvent obtained by mixing them. As a result, the problem of the evaporation rate can be easily solved, and ultrafine cyclic olefin based resin fibers can be easily produced.

In the anti-static method, when the polymer solution is supplied to the nozzle, when the volatile solvent is only a low boiling point component having an atmospheric pressure boiling point of 100 DEG C or lower, contamination or clogging of the nozzle needle tends to occur. Therefore, this problem can be solved by using a volatile solvent containing at least 20 mass% of a solvent having a boiling point of 140 ° C or higher at normal pressure. As described above, even when a volatile solvent having a low boiling point is used, mixing of a volatile solvent having a high boiling point prevents nozzle needle clogging and nozzle needle contamination, thereby making it possible to continuously and stably produce microfine fibers. Since the cyclic olefin resin used in the present invention is dissolved in various solvents, the range of solvent selection is wide and problems such as clogging of the needle are easily solved.

<Polymer solution>

The polymer solution is obtained by dissolving the cyclic olefin resin in the volatile solvent.

The polymer concentration of the polymer solution used in the present invention depends on the molecular weight of the polymer to be used. For example, when the polymer having a weight-average molecular weight of about 90000 is used, the polymer concentration is preferably in the range of 3% by mass to 20% desirable. And more preferably 7% by mass to 10% by mass. If the polymer concentration is less than 3% by mass, the viscosity of the solution becomes too low to form a fiber structure, which is not preferable. On the other hand, if it exceeds 20 mass%, the viscosity of the polymer solution becomes excessively large, and the fiber diameter of the resulting fiber becomes large, which is not preferable.

As the viscosity of the polymer solution, it is preferable that the viscosity of the polymer solution measured by the rotary clay system is in the range of 400 cps to 1000 cps.

&Lt; Electrospinning &

It is possible to radiate using the electrostatic spinning apparatus 1 as shown in Fig. The polymer solution is poured into the solution tank 11 and the polymer solution is pushed out from the nozzle needle 12 at an arbitrary flow rate and a high voltage is applied to the nozzle needle 12 by the high voltage generator 13, And the grounded copper plate 14, as shown in Fig. The polymer solution extruded into the electric field is split and further stretched by the Coulomb repulsion, so that the cyclic olefin based resin fiber is collected on the copper plate as shown in Fig.

The magnitude of the applied voltage is not particularly limited, but is preferably 5 kV to 100 kV. If the applied voltage is less than 5 kV, the Coulomb repulsion becomes small and fiberization tends to become difficult, which is not preferable. If it is more than 100 kV, sparking may occur between electrodes, which may result in inability to spin, which is not preferable. A more preferable range of the applied voltage is 10 kV to 30 kV.

The inner diameter of the nozzle needle 12 is not particularly limited, but is preferably 0.05 mm to 2 mm, and more preferably 0.1 mm to 1 mm in consideration of productivity and harmony with the fiber diameter obtained.

The feed rate of the polymer solution is not particularly limited, and is set to an appropriate value while changing various conditions according to the fiber diameter of the desired fine fiber. If the feed rate is too high, desired ultrafine fibers may not be obtained due to an insufficient evaporation of the volatile solvent and an insufficient Coulomb repulsion of droplets. If the feed rate is too low, the productivity of the fiber is lowered, which is not preferable. The preferable range of the feeding rate of the polymer solution is 0.01 ml / min to 0.1 ml / min per one nozzle needle.

The distance between the tip of the nozzle needle 12 and the copper plate 14 is preferably 5 cm to 30 cm for the solvent and the cyclic olefin resin used.

&Lt; Cyclic olefin-based resin fiber &

According to the present invention, by setting the conditions of the cyclic olefin resin, the volatile solvent and the electrostatic spinning appropriately, ultrafine cyclic olefin based resin fibers can be obtained. "Ultrafine fiber" refers to a fiber having an average fiber diameter of 0.01 μm to 100 μm. According to the present invention, an average fiber diameter of 0.1 탆 to 0.5 탆 can be easily realized.

In the electrostatic spinning method, since fine fibers are usually obtained in the form of being laminated on the copper plate 14, they can be used as a nonwoven fabric. Accordingly, the present invention provides a nonwoven fabric comprising the fibers of the present invention. The nonwoven fabric can be used as a battery separator, a culture medium for cell culture, and the like.

Example

Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited by these examples.

<Material>

[Cyclic olefin-based resin]

Cyclic olefin resin 1: TOPAS 8007F-04 (manufactured by TOPAS Advanced Polymers)

Cycloaliphatic resin 2: TOPAS 6013F-04 (manufactured by TOPAS Advanced Polymers)

Cycloaliphatic resin 3: TOPAS 6015F-04 (manufactured by TOPAS Advanced Polymers)

Cycloaliphatic resin 4: TOPAS 6017F-04 (manufactured by TOPAS Advanced Polymers)

Cyclic olefin resin 5: TOPAS 5013S-04 (manufactured by TOPAS Advanced Polymers)

[Volatile solvent]

A mixed solvent of chloroform (boiling point 62 ° C) and xylene (boiling point 144 ° C) (mixing ratio 80:20)

[Electrostatic Spinning Apparatus]

Electrostatic Spinning Apparatus: Nanofiber Electro Spinning Unit (manufactured by Kato Tech Co., Ltd.)

<Examples>

The materials shown in Table 1 were spun by the electrostatic protection method under the conditions described in Table 1 using the above-described electrostatic spinning device. A nonwoven fabric comprising a cyclic olefin based resin fiber was obtained. No clogging or contamination of the nozzle needle occurred even if the irradiation continued for more than 8 hours.

 [Measurement of Average Fiber Diameter]

The average fiber diameter of the cyclic olefin based resin fibers contained in the nonwoven fabric made of the cyclic olefin based resin fibers of Examples 1 to 5 was measured using a scanning electron microscope. Concretely, arbitrary ten fiber diameters were measured at a magnification of 5,000 to 10,000 times, and an average value thereof was defined as an average fiber diameter. The measurement results are shown in Table 1.

As shown in Table 1, it was confirmed that ultrafine cyclic olefin based resin fibers could be obtained by electrospinning.

1 Electrostatic radiator
11 solution tank
12 nozzle needle
13 High voltage generator
14 copper plate

Claims (5)

A step of spinning a polymer solution containing a volatile solvent and a cyclic olefin resin by electrospinning,
The fibers obtained after the spinning have an average fiber diameter of 0.01 탆 to 10 탆,
Wherein the volatile solvent contains at least two or more mixed solvents selected from the group consisting of chloroform, toluene, xylene, cyclohexane, and decalin
A method for producing a cyclic olefin based resin fiber.
The method according to claim 1,
Wherein the average fiber diameter is 0.1 占 퐉 to 0.5 占 퐉.
3. The method according to claim 1 or 2,
Wherein the mixed solvent contains chloroform and xylene.
3. The method according to claim 1 or 2,
Wherein the cyclic olefin resin has a glass transition point of 160 ° C or higher.
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