TWI707995B - Spinning method and device - Google Patents

Abstract

A nozzle device for spinning and a spinning method using the nozzle device for spinning, the nozzle device for spinning is provided with a nozzle, a polymer solution supply means, and a solvent vapor supply means, and the polymer solution supply means supplies the nozzle The polymer solution is sprayed from the tip of the nozzle; the solvent vapor supply means supplies gas at least around the polymer solution immediately after spraying, and the gas contains vapor of the same solvent as the solvent of the polymer solution. The solidification of the spinning solution at the tip of the nozzle used to discharge the spinning solution can be suppressed.

Description

Spinning method and device

The present invention relates to a spinning method of a polymer-containing fiber, which includes the step of spraying a polymer solution from the tip of a nozzle. It is a spinning method in which gas is supplied around the polymer solution immediately after being sprayed, and the spinning is performed. The gas contains vapor of the same solvent as the solvent of the polymer solution; and is related to the device used in the spinning method.

In recent years, formed bodies such as sheets composed of nanofibers have attracted attention as materials having characteristics that cannot be achieved by conventional formed fiber bodies because of their high specific surface area. As a manufacturing method (spinning method) of such nanofibers, the electrospinning method is well known.

In the electrospinning method, a solution (spinning solution) made by dissolving a polymer in a solvent is supplied to the tip of the spinning solution discharge nozzle, and a high voltage is applied between the tip of the nozzle and the electrode (collector), thereby on the collector A method of obtaining a fiber formed body. This method includes the steps of dissolving a polymer in a solvent to produce a solution (spinning solution), supplying the spinning solution to the tip of the nozzle and applying a high voltage, and directing the spinning solution from the tip of the nozzle toward the electrode (collecting In the step of spraying in the direction of the spray, the solvent is evaporated from the sprayed spinning solution to form a fiber. The step of forming the body, the step of eliminating the charge of the formed fiber formed body as an optional step, and the step of causing the fiber formed body to accumulate on the collector by eliminating the charge.

The problem of electrospinning is that continuous production can be carried out even when a volatile solvent is used in the spinning solution. In this regard, Patent Document 1 discloses a technique in which the nanofibers that are being produced are surrounded by a solvent near the conventional single-tube nozzle, and the produced nanofibers are physically prevented and/or washed by the solvent flow. The adsorption of rice fiber to the nozzle enables continuous production.

Patent Document 1: Japanese Patent Application Publication No. 2010-236133

The inventors found that in the electrospinning method, when a volatile solvent is used as the solvent of the spinning solution, the Taylor cone (Taylor cone) formed at the tip of the nozzle in the step of ejecting the spinning solution from the tip of the nozzle , Generated at the tip of the nozzle during spinning, by applying a voltage exceeding the surface tension of the droplet supplied to the tip of the nozzle, so that the droplet is stretched in the direction of the voltage to produce a generally cone-shaped one) to produce solidification , Its solid content grows over time, which is the cause of the deterioration of spinning stability, the reduction of spinning yield, and even the inability of continuous production. Moreover, it is known that this problem is not limited to the electrospinning method, which is a common problem of the spinning method in which the polymer solution is spun in the air.

The purpose of the present invention is to provide a method to solve this problem And devices, such as suppressing the solidification and growth of Taylor cones in electrospinning, and suppressing the solidification of the spinning solution at the tip of the nozzle in the spinning method where the polymer solution is spun in air.

In view of the above-mentioned problems, the inventors of the present invention have conducted intensive studies and found that the nozzle device of a spinning machine is equipped with a means for supplying a polymer solution as a raw material of the fiber to the nozzle and supplying the polymer to the tip of the nozzle. The method of solvent vapor of the solution, while supplying the solvent vapor of the polymer solution near the tip of the nozzle, the polymer solution as the raw material of the fiber is supplied to the nozzle to produce the fiber, thereby spitting out the spinning solution in the gas In the spinning method, the solidification of the spinning solution at the tip of the nozzle is suppressed, and the present invention is completed.

That is, the present invention is described below.

[1] A spinning nozzle device, which is equipped with a nozzle, a polymer solution supply means, and a solvent vapor supply means. The polymer solution supply means supplies a polymer solution to the nozzle and ejects the polymer solution from the tip of the nozzle; solvent vapor The supply means is to supply gas at least around the polymer solution immediately after spraying, and the gas contains vapor of the same solvent as the polymer solution.

[2] The spinning nozzle device described in [1] is configured to have a double tube structure composed of a nozzle, that is, an inner tube and an outer tube surrounding the inner tube. The gas in which the solvent is vapor of the same solvent is supplied from the space between the inner tube and the outer tube.

[3] A spinning method, which is a spinning method of a polymer-containing fiber, which includes the step of spraying a polymer solution from the tip of a nozzle, at least supplying gas around the polymer solution immediately after spraying, and spinning, The gas contains vapor of the same solvent as the solvent of the polymer solution.

[4] The spinning method described in [3], wherein the supplied gas contains a substance in the gas phase under spinning conditions, and the supplied gas contains the same solvent as the polymer solution solvent The vapor is saturated vapor.

The effect of the present invention is to suppress the solidification of the spinning solution at the tip of the nozzle for discharging the spinning solution in the spinning method in which the polymer solution is spun in the air. As a result, the clogging of the fiber components at the nozzle tip and poor ejection can be reduced, and the spinning stability and spinning yield can be improved, and continuous production can be performed.

1‧‧‧Dosing device

2‧‧‧Syringe

3‧‧‧Connecting hose

4‧‧‧Double nozzle

5‧‧‧Connecting hose

6‧‧‧Solvent foaming bottle

7‧‧‧Needle valve for control

8‧‧‧Volume Flowmeter

9‧‧‧Gas Supply Department

10‧‧‧Supply port of raw material solution (spinning solution)

11‧‧‧Supply port for gas containing solvent vapor

Fig. 1 is an overall view of a fiber manufacturing machine using an electrospinning method, which uses a double-tube nozzle as an example of the nozzle device of the present invention.

Fig. 2 shows a nozzle device having a double pipe structure as an example of the nozzle device of the present invention.

In the nozzle device of the present invention, as a means of supplying a polymer solution (spinning solution) as a raw material of fibers to the nozzle, it can be used as The nozzle device of a spinning device that spins a polymer solution is usually used. In addition, as a means for supplying the solvent vapor of the spinning solution to the tip of the nozzle, although there is no particular limitation, it is preferably one that does not hinder the formation of Taylor cones facing the spinning direction during spinning in the electrospinning method, for example, Adopted, it is configured to have an inner tube supplied with spinning solution as a nozzle, and an outer tube surrounding the inner tube. The gas containing the vapor of the spinning solution solvent flows from the space between the inner tube and the outer tube toward and from the nozzle The direction in which the spinning solution is ejected is supplied in the same direction. Thereby, at least the polymer solution immediately after spraying is in the atmosphere of the solvent vapor.

In the manufacturing method of the present invention, as the step of ejecting the polymer solution from the tip of the nozzle, a usual method among spinning methods in which the polymer solution is spun in a gas can be used. In addition, as a step of supplying a gas containing vapor of the same solvent as the solvent of the polymer solution around (near) the polymer solution at least immediately after being ejected, it is preferable that the electrospinning method does not interfere with the orientation during spinning. The method of forming Taylor cones in the spinning direction can be used, for example, a method of blowing a gas containing a solvent of the spinning solution around the spinning solution to be sprayed in the same direction as the direction in which the spinning solution is ejected from the nozzle. .

The present invention can be applied to any spinning technology as long as it is a spinning technology that produces fibers by gasifying its solvent from a spinning solution. For example, it can be applied to electrospinning, solution spinning, or force ) Spinning method, which is most suitable for electrospinning.

Examples of the types of polymers that can be used in the present invention include: polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyacrylonitrile, poly Nylon series such as acrylonitrile-methacrylate copolymer, polymethyl methacrylate, polyvinyl chloride, polyvinylidene chloride-acrylate copolymer, polyethylene, polypropylene, nylon 12, nylon-4,6, etc. , Polyaramide, polybenzimidazole, polyvinyl alcohol, cellulose, cellulose acetate, cellulose acetate butyrate, polyvinylpyrrolidone-vinyl acetate, poly(bis-(2-(2-methoxy -Ethoxyethoxy)) phosphazene), polypropylene oxide, polyethyleneimine, polyvinyl succinate, polyaniline, polyethylene sulfide, polyoxymethylene-oligooxyethylene, SBS Copolymer, polyhydroxybutyrate, polyvinyl acetate, polyethylene terephthalate, polyethylene oxide, collagen, polylactic acid, polyglycolic acid, poly D,L-lactic acid-glycolic acid copolymer, polyarylate , Polypropylene fumarate, polycaprolactone and other biodegradable polymers, polypeptides, proteins and other biopolymers, coal tar pitch, petroleum pitch and other pitch systems, etc., which are soluble in certain solvents. molecular.

The solvent of the polymer solution is the same as the solvent used as the solvent vapor. Examples of the types of solvents that can be used include: acetone, chloroform, ethanol, 2-propanol, methanol, toluene, tetrahydrofuran, water, benzene, benzene Methanol, 1,4-dioxane, 1-propanol, carbon tetrachloride, cyclohexane, cyclohexanone, dichloromethane, phenol, pyridine, trichloroethane, acetic acid, N,N-dimethyl Formamide, dimethyl sulfide, N,N-dimethylacetamide, 1-methyl-2-pyrrolidone, ethylene carbonate, propylene carbonate, dimethyl carbonate, acetonitrile, N-methyl Morpholine-N-oxide, butene carbonate, 1,4-butyrolactone, diethyl carbonate, diethyl ether, 1,2-dimethyloxyethane, 1,3-dimethyl-2-imidazolidinium Ketone, 1,3-dioxalate, ethyl methyl carbonate, methyl formate, 3-methyloxazolidin-2-one, methyl propionate, 2-methyltetrahydrofuran, cyclobutane, and selected from These ones Two or more mixed solvents in the solvent group.

As the nozzle structure with the double tube structure of the present invention, the inner diameter of the nozzle is preferably 0.15 to 1.07 mm, more preferably 0.34 to 0.84 mm. The inner diameter of the outer ring of the double tube nozzle that becomes the part where the solvent vapor is ejected is preferably 1.00 to 2.00 mm, more preferably 1.30 to 1.70 mm. If the inner diameter of the nozzle and the inner diameter of the outer ring are outside this range, solidified products are likely to be generated at the tip of the nozzle.

The flow rate range of the polymer solution is not particularly limited as long as it is a spinnable range, and it is preferably set to a range of 20 ml/h or less.

Regarding the vapor partial pressure of the solvent used, for example, a range of 1/2 or more of the saturated vapor pressure of the solvent can be adopted, and the solvent vapor is preferably saturated vapor. If the saturated vapor of the solvent is outside this range, a cured product is likely to be generated at the tip of the nozzle.

The gas flow rate of the solvent vapor is preferably 100 to 1000 ml/min, more preferably 200 to 800 ml/min. If the gas flow rate is outside this range, solidified products are likely to be generated at the tip of the nozzle.

Example [Manufacturing Equipment]

Fig. 1 is an example of the overall structure of a fiber manufacturing machine using electrospinning using the nozzle device of the present invention. Fig. 2 is a cross-sectional conceptual view of an example of the nozzle device of the present invention. In these figures, the nozzle device is composed of a nozzle and its outer tube. The nozzle is connected to the fiber raw material solution supply device, and the outer tube is connected to the solvent vapor supply device of the raw material solution. The raw material solution of the fiber is ejected from the space between the nozzle and the outer tube so as to surround the ejected solution with solvent vapor of the raw material solution.

[Preparation of polymer solution for spinning]

1 part by weight of polylactic acid glycolic acid copolymer (Purac (Purac) PURASORB PDLG5010), 1 part by weight of ethanol (Wako Pure Chemical Reagent Special Grade), and dye D&C Violet No. 2 (Spectrum Chemical Company (Spectrum) Chem.MFG.Corp)) 0.0042 parts by weight was weighed and put into the reagent bottle, and then stirred with a Vortex mixer (Vortex mixer) SI0286 at a scale of 10 for 5 minutes. Then, 8 parts by weight of dichloromethane was added, stirred with a vortex mixer SI0286 at a scale of 10 for 1 minute, and a high viscosity stirrer SNF-01 at 1000 rpm for 10 minutes to obtain a uniform polymer solution for spinning.

[Spinning using polymer solution for spinning]

Electrospinning was performed using the spinning solution obtained above. Using a double-tube nozzle with a nozzle inner diameter of 0.47mm and an outer ring inner diameter of 1.45mm, the number of nozzles is 12, the pitch interval between the nozzles is 70mm, the distance between spinning is 400mm, the spinning solution flow rate is 4ml/h, spinning A voltage of 35kV was applied, and spinning was performed under this condition. The fiber collection side uses a SUS304 collection plate 330 mm × 440 mm, and a voltage of -5 kV is applied to the collection plate. During spinning, 300ml/h of compressed air (0.3MPa) is supplied through a 3L glass airtight container filled with 500ml of dichloromethane to supply 300ml/h of saturated dichloride to the space between each nozzle and the outer tube Methane vapor. Under this condition, vertical The spinning continued for 25 minutes, and no solid matter was generated at the tip of the nozzle.

[Comparative example]

Except that saturated methylene chloride vapor was not supplied in the space between the nozzle and the outer tube during spinning, spinning was performed under the same conditions as in the above-mentioned example. Under this condition, solid content was generated at the tip of the nozzle right after spinning started, and 40 seconds after the start of spinning, the spinning could not continue due to the growth of the solid content at the tip of the nozzle.

[Industrial Utilization]

The present invention is suitable as a spinning method and device that has excellent spinning stability and spinning yield and can be continuously produced, for example, it can be used in the manufacturing of non-woven fabrics.

1‧‧‧Dosing device

2‧‧‧Syringe

3‧‧‧Connecting hose

4‧‧‧Double nozzle

5‧‧‧Connecting hose

6‧‧‧Solvent foaming bottle

7‧‧‧Needle valve for control

8‧‧‧Volume Flowmeter

9‧‧‧Gas Supply Department

Claims (4)

A spinning nozzle device is provided with a nozzle, a polymer solution supply means, and a solvent vapor supply means. The polymer solution supply means supplies a polymer solution to the nozzle and ejects the polymer solution from the tip of the nozzle; the solvent vapor supply The method is to supply gas at least around the polymer solution immediately after spraying. The gas is vapor containing the same solvent as the polymer solution and is used to suppress the solidification of the polymer solution at the tip of the nozzle. The spinning nozzle device according to claim 1, which is configured to have a double tube structure composed of a nozzle, that is, an inner tube and an outer tube surrounding the inner tube, containing the same solvent as the polymer solution The vapor of the solvent is supplied from the space between the inner tube and the outer tube. A spinning method is a spinning method of fiber containing polymer, which includes the step of spraying polymer solution from the tip of the nozzle, at least supplying gas around the polymer solution immediately after spraying and spinning, the gas is The vapor containing the same solvent as the polymer solution is used to suppress the curing of the polymer solution at the tip of the nozzle. The spinning method according to claim 3, wherein the supplied gas contains a substance that is in the gas phase under the conditions of spinning, and the supplied gas contains the same solvent as the polymer solution's solvent. Saturated vapor.

Images