A method and apparatus for centrifugally producing nanofiber yarns

Abstract

The present application relates to a kind of centrifugal production nanofiber yarn method and device, method is: in the process of preparing nanofiber using centrifugal spinning method, the horizontal outward airflow generated by spinning disk rotation is converted into spiral airflow field to draft the spinning solution ejected from spinneret and is twisted to prepare nanofiber yarn;Device includes spinning disk (4), receiving device, driving device and self-twist device (5);Spinning disk (4) includes vertical cylinder I, cylinder I inside is equipped with spinning solution storage cavity, cylinder I peripheral surface is equipped with spinneret with spinning solution storage cavity communication, the liquid direction of spinneret is horizontal direction;Self-twist device (5) includes horizontal cylinder pipe I, horizontal cylinder pipe II, rolling ball (5-1), fan blade (5-4), wind collector and wind collector (5-2).The present application can effectively improve twisting effect, spin out special-shaped multi-component fiber, and can realize continuous liquid supply without shutdown.

Description

Technical Field

[0001] This invention belongs to the field of spinning equipment technology, and relates to a method and apparatus for centrifugal production of nanofiber yarn. Background Technology

[0002] There are two main types of nanofiber production and processing equipment. One type prepares nanofibers by electrospinning and then uses a twisting device to bundle and twist the fibers into yarn. The other type prepares nanofibers by centrifugal spinning and then uses a twisting device to bundle and twist the fibers into yarn.

[0003] Patent CN105734693A discloses a dual-electrode electrospinning device and its usage method, which twists nanofibers using a collector and rollers. However, the main drawback of the device based on electrospinning for nanofiber yarn is its low production efficiency and high requirements for spinning raw materials. Patent CN106811845B discloses a spherical brush-type batch nanofiber yarn processing device and its usage method. Although the needleless electrospinning method with a free liquid surface can greatly improve spinning efficiency, the evaporation of the spinning solution when exposed to air causes uneven spinning and clogging, affecting spinning efficiency. Therefore, the efficiency of preparing nanofibers by electrospinning is often low. Thus, centrifugal spinning is a more ideal method to improve spinning efficiency.

[0004] Patent CN108085758A discloses a nano-yarn production device. This device uses centrifugal spinning to prepare nanofibers. The fibers are bundled and twisted by rotating a disc. This method has high fiber preparation efficiency, but because the micro and nanofibers are not received according to the direction of centrifugal force when they come out, the fibers are disordered, resulting in low fiber orientation. Ultimately, this leads to low mechanical properties and makes multi-component spinning impossible.

[0005] Patent CN201910561697-2 discloses a composite centrifugal spinning device with two chamber structures. Two spinning solutions are poured in and the spinning machine rotates to produce composite fibers of the two materials. However, due to the limited number of spinning channels and the number of liquids supplied, the type of composite fiber membrane produced by this method is limited, and it can only produce fiber membranes composed of two materials.

[0006] Patent CN105887223A discloses a high-speed centrifugal spinning device and a method for preparing nanofiber yarn in one step. The fiber is collected by a cylindrical collector, which rotates and twists itself. Then, it is wound up and collected by rollers. However, the twisting effect of this device is poor, it only has a certain bundling function, and it cannot realize multi-component spinning and yarn spinning.

[0007] Patent CN108796687B discloses a device and method for continuous preparation of self-twisted nanofiber yarn, which twists and bundles the ejected fibers through airflow and electrostatic force. Because this device uses an air field and an electric field, the equipment requirements are complex, there are too many uncontrollable factors, it is difficult to achieve stable twisting, and it cannot achieve the function of multi-component nanospinning. Summary of the Invention

[0008] The purpose of this invention is to solve the problems existing in the prior art and to provide a method and apparatus for centrifugal production of nanofiber yarns.

[0009] To achieve the above objectives, the present invention adopts the following solution:

[0010] A method for producing nanofiber yarn by centrifugation involves converting the horizontal outward airflow generated by the rotation of the spinning disc into a spiral airflow field to stretch and twist the spinning solution ejected from the spinneret to obtain nanofiber yarn.

[0011] The present invention also provides an apparatus for centrifugal production of nanofiber yarns, which implements the centrifugal production method of nanofiber yarns as described above, including a spinning disc, a receiving device and a driving device, and further including a self-twisting device;

[0012] The spinning disc includes a vertical cylindrical tube I, with a spinning solution storage chamber inside the cylindrical tube I. A spinneret is provided on the circumference of the cylindrical tube I, which communicates with the spinning solution storage chamber. The spinneret exits the solution in a horizontal direction.

[0013] The self-twisting device is located at the top of the spinning disc and includes a horizontal cylindrical tube I, a horizontal cylindrical tube II, rolling beads, fan blades, an air collecting hood, and an air concentrator, which can bundle and twist multi-component fibers.

[0014] Cylindrical tube I is connected to cylindrical cylinder I on its circumference; cylindrical tube I is fitted onto cylindrical tube II, and rolling balls are located between cylindrical tube I and cylindrical tube II, the three of which constitute a bearing; cylindrical tube II is fitted onto spinneret, and fan blades are fixed inside cylindrical tube II and distributed around spinneret.

[0015] The air collector is located above the cylindrical tube I and is detachably connected to the cylindrical tube I. The air collector is also fixedly connected to the cylindrical tube I. The air collector is used to concentrate the horizontal outward airflow generated by the rotation of the spinning disc into the cylindrical tube II.

[0016] The air-gathering hood is located on the side of the cylindrical tube I away from the cylindrical cylinder I and is connected to it; the size of the air-gathering hood decreases along the direction away from the cylindrical tube I; the end of the air-gathering hood away from the cylindrical tube I is provided with a yarn outlet.

[0017] One of the objectives of this invention is to solve the problems of poor twisting effect and low fiber orientation in the existing centrifugal spinning method, as detailed below:

[0018] Existing centrifugal spinning techniques involve complex equipment and poor twisting effects. This invention, by installing a self-twisting device, utilizes the airflow generated during spinning to achieve fiber twisting without the need for an external twisting device. This is simple and efficient. When the spinning disc rotates, it generates a horizontal outward airflow, which drives the fan blades to rotate, creating a spiral airflow field that stretches, polymerizes, and twists the spinning solution ejected from the spinnerets. The twisted yarn is then ejected from the yarn outlet and received by a receiving device. Furthermore, existing centrifugal spinning methods primarily involve placing the spun fibers into a twisting device. This process disrupts fiber orientation, resulting in inconsistent fiber direction and low fiber orientation in the yarn, leading to poor yarn mechanical properties. Therefore, preserving fiber orientation has a significant impact on the final yarn's mechanical properties. This invention, by installing a detachable self-twisting device, ensures that the spinning solution from the same row of needles is stretched by centrifugal force in the same direction during spinning, resulting in fibers in the same direction and high fiber orientation. After passing through the twisting device, the fiber orientation is not destroyed. After yarn formation, the yarn is subjected to continuous centrifugal force, and the yarn orientation is not destroyed. Finally, the yarn is received by a circumferential receiving device, thus completely preserving the oriented yarn. Therefore, the resulting yarn has high orientation and good mechanical properties.

[0019] The device of this invention produces composite micro / nano fibers and yarns at speeds hundreds of times faster than electrospinning equipment, and has promising applications in tissue engineering, energy, and filtration fields.

[0020] As a preferred technical solution:

[0021] As described above, in a centrifugal device for producing nanofiber yarns, the length of cylindrical tube I is greater than that of cylindrical tube II, and the ends of cylindrical tubes I and II that are opposite to the cylindrical tube I are flush.

[0022] As described above, the centrifugal device for producing nanofiber yarn has an air collection hood that is a vertical cylindrical tube II. The lower end of the cylindrical tube II is completely open, and the upper end is partially open to form a ring. The cylindrical tube II is coaxial with the cylindrical tube I and has the same outer diameter. The side wall of the cylindrical tube II is provided with an air inlet, which is connected to the hollow part of the cylindrical tube I.

[0023] As described above, the centrifugal device for producing nanofiber yarns has the following configuration: the number of spinning solution storage chambers in the spinning disc is n, where n is a positive integer greater than or equal to 1; the number of spinning solution channels in the spinneret is 1 or m, where m spinning solution channels are connected to different spinning solution storage chambers, where m is a positive integer greater than 1 and less than or equal to n. Different paths can be controlled for different spinning solutions, thereby enabling the preparation of multi-component fibers and yarns. Various structural composite fibers can be flexibly prepared using customized anisotropic spinnerets, and the diameter of fibers and yarns can also be flexibly adjusted by changing the orifice diameter of the spinnerets.

[0024] The second objective of this invention is to solve the problem of difficulty in achieving multi-component spinning in the prior art. The number of spinning solution storage chambers in the spinning disc and the number of spinning solution channels in the spinneret of this invention can be designed according to application requirements to achieve multi-component spinning.

[0025] As described above, a centrifugal device for producing nanofiber yarns, where n>1, has a core-sheath spinneret and includes one horizontal straight tube a, one horizontal straight tube b, and one "L"-shaped bend c. The horizontal straight tube a is fitted onto the horizontal straight tube b, and the inner diameter of the horizontal straight tube a is larger than the outer diameter of the horizontal straight tube b. One end of both horizontal straight tubes a and b is connected to the circumferential surface of a cylindrical tube I, and the other end is flush with it. One end of the "L"-shaped bend c is connected to the circumferential surface of the cylindrical tube I, and the other end is connected to the horizontal straight tube a. The horizontal straight tube b and the "L"-shaped bend c are respectively connected to different spinning solution storage chambers. The "L"-shaped bend c is connected to the horizontal straight tube a, while the horizontal straight tube a is not connected to the spinning solution storage chamber.

[0026] As described above, a centrifugal device for producing nanofiber yarns, where n>1, has an island-shaped spinneret, comprising one horizontal straight tube d and one or more "Z"-shaped bends e, wherein the "Z"-shaped bend e is composed of an "L"-shaped bend e1 and a horizontal straight tube e2; one end of the horizontal straight tube d and the "Z"-shaped bend e are simultaneously connected to the circumferential surface of the cylindrical tube I, and the other end is flush with it; the horizontal straight tube d is fitted onto the horizontal straight tube e2, and the inner diameter of the horizontal straight tube d is larger than the outer diameter of the horizontal straight tube e2; the horizontal straight tube d and the "Z"-shaped bend e are respectively connected to different spinning solution storage chambers.

[0027] The centrifugal device for producing nanofiber yarns as described above, n=3; the spinning disc also includes a horizontal annular plate a, a horizontal annular plate b, a vertical cylindrical tube III, and a vertical cylindrical tube IV.

[0028] Annular plate a is located above annular plate b and is spaced apart from it; the outer ring of annular plate a is connected to the inner wall of cylindrical tube I, and the inner ring of annular plate a is fitted on the lower end of cylindrical tube III; the outer ring of annular plate b is connected to the inner wall of cylindrical tube I, and the inner ring of annular plate b is fitted on the lower end of cylindrical tube IV, and cylindrical tube IV is inserted into cylindrical tube III, with the upper ends of both being flush with cylindrical tube I.

[0029] The upper section of cylindrical cylinder I, the annular plate a, and the cylindrical tube III together form spinning solution storage chamber I; the middle section of cylindrical cylinder I, the annular plate a, the cylindrical tube III, the annular plate b, and the cylindrical tube IV together form spinning solution storage chamber II; and the lower section of cylindrical cylinder I, the annular plate b, and the cylindrical tube IV together form spinning solution storage chamber III.

[0030] The spinning disc is essentially composed of a first spinning disc, a second spinning disc, and a third spinning disc, all formed in one piece. The first spinning disc is the upper section of cylindrical tube I. The second spinning disc is composed of the middle section of cylindrical tube I, annular plate a, and cylindrical tube III. The third spinning disc is composed of the lower section of cylindrical tube I, annular plate b, and cylindrical tube IV. The first, second, and third spinning discs are detachably connected for easy cleaning and improved cleaning efficiency.

[0031] The centrifugal nanofiber yarn production device described above further includes a liquid supply device located above the spinning disc. The liquid supply device includes n liquid delivery tubes, which are respectively inserted into n spinning liquid storage chambers. The flow rate of different spinning liquids can be controlled individually. The liquid supply speed affects the uniformity and diameter of the fibers. In conjunction with the function of the spinning disc, the diameter, material ratio, and structure of multi-component fibers and yarns can be flexibly adjusted.

[0032] The centrifugal nanofiber yarn production apparatus described above further includes a spinning box, a spinning disc, a receiving device, a driving device, a self-twisting device, and a liquid supply device, all located inside the spinning box. The spinning box is located on the outermost side and is used to control the temperature and humidity of the spinning environment and the motion parameters of each component, as well as to isolate the outside air.

[0033] As described above, the centrifugal device for producing nanofiber yarn has one or more spinnerets, and the number of self-twisting devices is the same as that of the spinnerets, with each device corresponding to the other. All self-twisting devices share the same air collection hood.

[0034] As described above, the centrifugal device for producing nanofiber yarns includes a cylindrical receiving plate as the receiving device. The spinning disc and the self-twisting device are both located inside the receiving plate, which is coaxial with the cylindrical tube I. The receiving plate controls the diameter of the fibers and yarns by horizontal movement (the closer the distance, the thicker the fibers; the farther the distance, the thinner the fibers). It controls the stacking structure of the multi-component fiber membrane and multi-component yarns by vertical movement. The receiving plate can also dynamically receive fibers during the spinning process, which changes the stacking structure of the collected fiber membrane and yarns. It can also be connected to a subsequent roller collecting device to wind and collect the fiber membrane or yarns. Alternatively, the receiving device can be a horizontal sheet-like spinning platform located below the spinning disc and connected to a lifting mechanism. When the spinning platform is used for receiving, the fibers are vertically stacked.

[0035] The centrifugal nanofiber yarn production device described above uses a servo motor as the driving device. The servo motor is fixed at the bottom of the spinning box and located below the spinning platform. It controls the lifting and lowering of the spinning platform, the rotation speed of the spinning disc, and the horizontal and vertical movement of the receiving plate through a rotating shaft, thereby achieving the effect of adjusting the diameter of the fiber and yarn.

[0036] The apparatus of this invention can produce multi-component fiber membranes with complex structures, including both oriented and non-oriented fiber membranes. For example, it can generate biomimetic multilayer vascular stents in a single process. It can also produce special fiber structures such as core-shell and island-type structures, and composite yarns. Furthermore, it allows for continuous liquid supply without downtime, which causes fiber unevenness. This invention improves production efficiency and spinning uniformity.

[0037] Beneficial effects

[0038] (1) A centrifugal method for producing nanofiber yarn according to the present invention effectively improves the twisting effect by converting the horizontal outward airflow generated by the rotation of the spinning disc into a spiral airflow field.

[0039] (2) The centrifugal nanofiber yarn production device of the present invention has an innovative design of a detachable multi-layer spinning disc, which makes the spinning disc very easy to disassemble and clean, and improves the efficiency of use.

[0040] (3) The centrifugal nanofiber yarn production device of the present invention realizes the function of multi-component composite spinning by individually controlling different spinning solutions, and can spin heterogeneous multi-component fibers by designing the spinneret.

[0041] (4) The centrifugal nanofiber yarn production device of the present invention can continuously supply liquid without stopping the machine, thereby improving production efficiency and spinning uniformity. Attached Figure Description

[0042] Figure 1 This is a three-dimensional structural schematic diagram of a centrifugal device for producing nanofiber yarn according to the present invention.

[0043] Figure 2 This is a schematic cross-sectional view of the integral structure of the spinning disc, self-twisting device, and spinneret needle of the present invention.

[0044] Figure 3 This is a three-dimensional structural diagram of the integrated spinning disc, self-twisting device, and spinneret of the present invention (excluding the trapezoidal wind-gathering shroud);

[0045] Figure 4 This is a left view of the entire assembly of the spinning disc, self-twisting device, and spinneret needle of the present invention.

[0046] Figure 5 The left view shows the entire assembly of the spinning disc, self-twisting device, and spinneret needle of the present invention (excluding the trapezoidal wind-gathering shroud);

[0047] Figure 6 This is a schematic cross-sectional view of the core-shaped spinneret of the present invention.

[0048] Figure 7 This is a schematic cross-sectional view of the island-shaped spinneret of the present invention;

[0049] Figure 8 The figure shows the fiber diameters and contact angles of the inner and outer layers of the multi-component directional humidification membrane prepared in Example 2 of the present invention. As can be seen from the figure, the multi-component directional humidification membrane ultimately achieves a gradient change in pore size and hydrophilicity / hydrophobicity of each layer, with the pore size becoming smaller and the hydrophilicity becoming stronger.

[0050] Figure 9 The image shows a SEM image of the PCL / PLGA / PLA island-island composite fiber prepared in Example 3 of the present invention. As can be seen from the image, the average deviation angle of the prepared island-island composite fiber is only 2.37°, indicating that the composite fiber has a high degree of orientation.

[0051] Figure 10 The image shows an SEM image of the oriented multi-component PCL / PLGA composite fiber prepared in Example 4 of the present invention. As can be seen from the image, the average deviation angle of the prepared PCL / PLGA composite fiber is only 1.65°, indicating that the composite fiber has a high degree of orientation.

[0052] Figure 11 This is a distribution diagram of fiber orientation angle in the oriented multi-component PCL / PLGA yarn obtained in Example 5 of the present invention. As can be seen from the figure, the average orientation angle of the fibers in the yarn obtained in this example along the yarn axial direction is only 4.65, indicating that the fiber orientation of the yarn is good.

[0053] Figure 12 The figure shows the diameter distribution of the oriented multi-component PCL / PLGA yarn obtained in Example 5 of the present invention. As can be seen from the figure, the standard deviation of the PCL / PLGA yarn obtained in this example is 70 nm, which is within the allowable error range, indicating that the yarn diameter is uniform.

[0054] Among them, 1-spinning box, 2-servo motor, 3-spinning platform, 4-spinning disc, 4-1-circular ring plate a, 4-2-circular ring plate b, 4-3-cylindrical tube I, 4-4-cylindrical tube III, 4-5-cylindrical tube IV, 5-self-twisting device, 5-1-rolling ball, 5-2-air concentrator, 5-3-yarn outlet, 5-4-fan blade, 5-5-air inlet, 5-6-cylindrical tube I, 5-7-cylindrical tube II, 6-island-shaped spinneret, 6-1- Horizontal straight tube d, 6-2- "L" shaped bend e1, 6-3-Horizontal straight tube e2, 7-Sheet core spinneret, 7-1-Horizontal straight tube a, 7-2-Horizontal straight tube b, 7-3- "L" shaped bend c, 8-Receiving plate, 9-Liquid supply device, 10-First spinning disc, 11-Second spinning disc, 12-Third spinning disc, 13-Spinning solution storage chamber I, 14-Spinning solution storage chamber II, 15-Spinning solution storage chamber III, 16-Ordinary spinneret. Detailed Implementation

[0055] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0056] The detection methods for the relevant performance in the following embodiments are as follows:

[0057] Method for detecting water contact angle: Contact angle was measured using a contact angle measuring instrument (OCA20, Dataphysics, Germany). For the water contact angle test of the outermost layer and transition layer of PCL in Example 2, the multi-component directional moisture-wicking membrane was prepared separately using the same process parameters as in Example 2. During the preparation process, after obtaining the outermost layer of PCL, the liquid supply and servo motor were stopped, and the water contact angle was measured using the contact angle measuring instrument. After obtaining the transition layer, the liquid supply and servo motor were stopped, and the water contact angle was measured using the contact angle measuring instrument. Each layer was tested three times, and the average value was taken.

[0058] Method for detecting the average deviation angle: After sputtering gold onto the sample, the sample is observed and images are captured using a field emission scanning electron microscope (DXS-10ACKT, Shanghai Institute of Electronic Optics Technology) at a voltage of 10.0 kV. The images are then imported into ImageJ for processing. 200 fibers are randomly selected for average deviation angle analysis. That is, a fiber orientation direction is fixed, and the angle between each fiber and that direction is measured. The average deviation angle of the fibers in the yarn along the yarn axis is obtained by calculating the average deviation angle.

[0059] The sources of the relevant substances in the following embodiments are as follows:

[0060] PCL (polycaprolactone): Manufacturer: Sigma-Aldrich, Grade: 900824;

[0061] PLGA (polylactic acid-glycolic acid copolymer): Manufacturer: Maclean, brand name: P879466-500mg;

[0062] PLA (polylactic acid): Manufacturer: Sigma-Aldrich, grade 38534;

[0063] Collagen: Manufacturer: Sigma-Aldrich, Product Code: 01487111.

[0064] Example 1

[0065] A centrifugal device for producing nanofiber yarns, such as Figures 1-7 As shown, it includes a spinning box 1, a spinning disc 4, a self-twisting device 5, a receiving device, a driving device, and a liquid supply device 9.

[0066] The spinning disc 4 includes a horizontal annular plate a 4-1, a horizontal annular plate b 4-2, a vertical cylindrical tube I 4-3, a vertical cylindrical tube III 4-4, and a vertical cylindrical tube IV 4-5;

[0067] like Figure 2As shown, annular plate a 4-1 is located above annular plate b 4-2 and spaced apart from it; the outer ring of annular plate a 4-1 is connected to the inner wall of cylindrical tube I 4-3, and the inner ring of annular plate a 4-1 is fitted onto the lower end of cylindrical tube III 4-4; the outer ring of annular plate b 4-2 is connected to the inner wall of cylindrical tube I 4-3, and the inner ring of annular plate b 4-2 is fitted onto the lower end of cylindrical tube IV 4-5, cylindrical tube IV 4-5 is inserted into cylindrical tube III 4-4, and the upper ends of both are flush with cylindrical tube I 4-3; the upper section of cylindrical tube I 4-3, annular plate a 4-1, and cylindrical tube III 4-4 together form spinning solution storage cavity I13, and the middle section of cylindrical tube I 4-3, annular plate a 4-1, cylindrical tube III 4-4, and annular plate b 4-2 are connected to the inner wall of cylindrical tube I 4-3, and the inner ring of annular plate b 4-2 is fitted onto the lower end of cylindrical tube IV 4-5, cylindrical tube IV 4-5 is inserted into cylindrical tube III 4-4, and the upper ends of both are flush with cylindrical tube I 4-3; the upper section of cylindrical tube I 4-3, annular plate a 4-1, cylindrical tube III 4-4, and annular plate b 4-2 together form spinning solution storage cavity I13, and the middle section of cylindrical tube I 4-3, annular plate a 4-1, cylindrical tube III 4-4, and annular plate b 4-2 are connected to the inner wall of cylindrical tube I 4-3, cylindrical tube III 4-4, and cylindrical tube III 4-4 are connected to the inner wall of cylindrical tube III 4-4, cylindrical tube III 4-4, and cylindrical tube III 4-4 are connected to the inner wall of cylindrical tube III 4-4, cylindrical tube III 4-2 and cylindrical tube IV 4-5 together form spinning solution storage cavity II 14. The lower section of cylindrical tube I 4-3, annular plate b 4-2 and cylindrical tube IV 4-5 together form spinning solution storage cavity III 15. Spinning disc 4 is equivalent to being composed of an integrally formed first spinning disc 10, an integrally formed second spinning disc 11 and an integrally formed third spinning disc 12. The first spinning disc 10 is the upper section of cylindrical tube I 4-3. The second spinning disc 11 is composed of the middle section of cylindrical tube I 4-3, annular plate a 4-1 and cylindrical tube III 4-4. The third spinning disc 12 is composed of the lower section of cylindrical tube I 4-3, annular plate b 4-2 and cylindrical tube IV 4-5. The first spinning disc 10, the second spinning disc 11 and the third spinning disc 12 are detachably connected.

[0068] The cylindrical tube I 4-3 is provided with a spinneret that communicates with the spinning solution storage chamber; the liquid outlet direction of the spinneret is horizontal.

[0069] The spinnerets can be selected from the following types: ordinary spinneret 16, island-type spinneret 6, or core-type spinneret 7;

[0070] Each ordinary spinneret 16 has one internal spinning solution channel, which is connected to one spinning solution storage chamber.

[0071] like Figure 7 As shown, the island-shaped spinneret 6 includes one horizontal straight tube d 6-1 and two "Z"-shaped bends e. The "Z"-shaped bends e are composed of an "L"-shaped bend e1 6-2 and a horizontal straight tube e2 6-3. One end of the horizontal straight tube d 6-1 and the "Z"-shaped bends e are connected to the circumference of the cylindrical tube I 4-3, and the other end is flush with it. The horizontal straight tube d 6-1 is fitted onto the horizontal straight tube e2 6-3, and the inner diameter of the horizontal straight tube d6-1 is larger than the outer diameter of the horizontal straight tube e2 6-3. The horizontal straight tube d 6-1 and the "Z"-shaped bends e are respectively connected to different spinning solution storage chambers.

[0072] Each island-shaped spinneret 6 has 3 spinning solution channels, and the 3 spinning solution channels are connected to different spinning solution storage chambers respectively.

[0073] like Figure 6 As shown, the core-shaped spinneret 7 includes a horizontal straight tube a 7-1, a horizontal straight tube b 7-2, and an "L"-shaped bend c 7-3; the horizontal straight tube a 7-1 is fitted onto the horizontal straight tube b 7-2, and the inner diameter of the horizontal straight tube a 7-1 is larger than the outer diameter of the horizontal straight tube b 7-2. One end of both the horizontal straight tubes a 7-1 and b 7-2 is connected to the circumferential surface of the cylindrical tube I 4-3, and the other end is flush with it; one end of the "L"-shaped bend c 7-3 is connected to the circumferential surface of the cylindrical tube I 4-3, and the other end is connected to the horizontal straight tube a 7-1; the horizontal straight tube b 7-2 and the "L"-shaped bend c 7-3 are respectively connected to different spinning solution storage chambers, the "L"-shaped bend c 7-3 is connected to the horizontal straight tube a 7-1, and the horizontal straight tube a 7-1 is not connected to the spinning solution storage chamber;

[0074] Each core-shaped spinneret 7 has two spinning solution channels, and the two spinning solution channels are connected to different spinning solution storage chambers respectively.

[0075] like Figures 2-3 As shown, the self-twisting device 5 includes a horizontal cylindrical tube I 5-6, a horizontal cylindrical tube II 5-7, a rolling ball 5-1, a fan blade 5-4, an air collecting shroud, and an air concentrator shroud 5-2;

[0076] Cylindrical tube I 5-6 is connected to the circumferential surface of cylindrical tube I 4-3; cylindrical tube I 5-6 is fitted onto cylindrical tube II 5-7, and rolling ball 5-1 is located between cylindrical tube I 5-6 and cylindrical tube II 5-7, the three forming a bearing; cylindrical tube II 5-7 is fitted onto the spinneret, and fan blade 5-4 is fixed inside cylindrical tube II 5-7 and distributed around the spinneret; the length of cylindrical tube I 5-6 is greater than that of cylindrical tube II 5-7, and the ends of cylindrical tube I 5-6 and cylindrical tube II 5-7 opposite to cylindrical tube I 4-3 are flush;

[0077] The air collecting hood is a vertical cylindrical tube II, with its lower end fully open and its upper part partially open to form a ring. Cylindrical tube II is located above cylindrical tube I 4-3, coaxial with cylindrical tube I 4-3, and has the same outer diameter. Cylindrical tube II is detachably connected to cylindrical tube I 4-3, and is also fixedly connected to cylindrical tube I 5-6. The side wall of cylindrical tube II is provided with an air inlet 5-5, which communicates with the hollow part of cylindrical tube I 5-6.

[0078] The air collecting hood is used to concentrate the horizontal outward airflow generated by the rotation of the spinning disc 4 into the cylindrical tube II 5-7;

[0079] The wind-concentrating hood 5-2 is located on the side of the cylindrical tube I 5-6 away from the cylindrical cylinder I 4-3 and is connected to it; the size of the wind-concentrating hood decreases along the direction away from the cylindrical tube I 5-6; the end of the wind-concentrating hood away from the cylindrical tube I 5-6 is provided with a yarn outlet 5-3.

[0080] The number of self-twisting devices 5 corresponds to the number of spinnerets; all self-twisting devices 5 share the same air collection hood.

[0081] like Figure 1 As shown, the liquid supply device 9 includes 3 liquid infusion tubes, which are respectively inserted into 3 spinning liquid storage chambers;

[0082] The receiving device is a cylindrical receiving plate 8, with the spinning disc 4 and the self-twisting device 5 both located inside the receiving plate 8. The receiving plate 8 is coaxial with the cylindrical tube I 4-3; or, the receiving device is a horizontal sheet-shaped spinning platform 3, located below the spinning disc 4 and connected to a lifting mechanism.

[0083] The driving device is a servo motor 2; the servo motor 2 is fixed at the bottom of the spinning box 1 and located below the spinning platform 3. It controls the lifting and lowering of the spinning platform 3, the rotation speed of the spinning disc 4, and the horizontal and vertical movement of the receiving plate 8 through the rotating shaft.

[0084] The spinning disc 4, receiving device, driving device, self-twisting device 5, and liquid supply device 9 are all located inside the spinning box 1.

[0085] Example 2

[0086] A centrifugal device for producing nanofiber yarn is basically the same as in Example 1 (where the receiving device is a receiving plate), except that: the device in this example does not include a self-twisting device; the spinnerets arranged on the circumference of the cylindrical tube I are all ordinary spinnerets, and the number is 8.

[0087] A method for centrifugally producing multi-component directional moisture-wicking membranes, using the aforementioned centrifugally produced nanofiber yarn apparatus, is described below:

[0088] Polycaprolactone (PCL) was added to dichloromethane (DCM) to prepare spinning solution A with a concentration of 18 wt%, and collagen was added to HFIP (hexafluoroisopropanol) to prepare spinning solution B with a concentration of 12 wt%. Both spinning solutions were added to the supply device. The receiving plate was set to a receiving distance of 30 cm. When the spinning disc speed reached 4000 r / min, spinning solution A was fed into the first spinning disc at a flow rate of 15 ml / min. After 30 seconds, the receiving distance was gradually adjusted to 35 mm, and the spinning disc speed was increased to 6000 r / min. Spinning solution B was fed into the second spinning disc at a flow rate of 12 ml / min for 2 minutes. Then, the supply of spinning solution A was stopped, and the spinning disc rotation speed was gradually adjusted to 8000 r / min. After 30 seconds, the supply of spinning solution B was stopped, thus producing a multi-component directional moisture-wicking film. The inner diameter of the four spinnerets on the first spinning disc was 0.9 mm (i.e., the inner diameter of the spinning solution channel connected to the first spinning disc was 0.9 mm), and the inner diameter of the spinnerets on the second spinning disc was 0.6 mm (i.e., the inner diameter of the spinning solution channel connected to the second spinning disc was 0.6 mm).

[0089] The prepared multi-component directional moisture-wicking membrane consists of an outermost PCL layer with an average fiber diameter of 10.62 μm, a two-component transition layer with an average diameter of 1.59 μm, and an innermost collagen fiber layer with an average fiber diameter of 232 nm. The water contact angles are 120°, 90°, and 30°, respectively.

[0090] Example 3

[0091] A centrifugal device for producing nanofiber yarn is basically the same as in Example 1 (where the receiving device is a receiving plate), except that: the device in this example does not include a self-twisting device; the spinnerets arranged on the circumference of the cylindrical tube I are all island-shaped spinnerets, and the number is 4.

[0092] A method for centrifugally producing island-of-sea composite fibers, using the apparatus described in this embodiment for centrifugally producing nanofiber yarns, is as follows:

[0093] PCL (polycaprolactone) was added to DCM (dichloromethane) to prepare spinning solution A with a concentration of 15 wt%. PLGA (polylactic acid-glycolic acid copolymer) was added to DCM to prepare spinning solution B with a concentration of 12.5 wt%. PLA (polylactic acid) was added to DCM to prepare spinning solution C with a concentration of 10 wt%. All three spinning solutions were added to the feeding device. When the spinning disc speed reached 7000 r / min, spinning solutions A, B, and C were fed at 15 ml / min, 1 ml / min, and 1 ml / min, respectively. The solution flows into the first, second, and third spinning discs at flow rates of 2 ml / min and 10 ml / min, respectively; after drawing and collection by the receiving plate, PCL / PLGA / PLA island-island composite fibers are obtained; wherein, the receiving distance from the receiving plate to the spinning disc is 30 cm, and the inner diameters of the island-shaped spinnerets on the first, second, and third spinning discs are 0.5 mm, 1.2 mm, and 0.5 mm, respectively (that is, the inner diameters of the spinning solution channels connected to the first, second, and third spinning discs are 0.5 mm, 1.2 mm, and 0.5 mm, respectively).

[0094] The average diameter of the obtained PCL / PLGA / PLA island-sea composite fiber is 623 nm, and the average deflection angle of the fiber in the yarn along the yarn axis is 2.37°.

[0095] Example 4

[0096] A centrifugal device for producing nanofiber yarn is basically the same as in Example 1 (where the receiving device is a receiving plate), except that: in this embodiment, the spinnerets arranged on the circumference of the cylindrical tube I are all core-shaped spinnerets, and the number is 4.

[0097] A method for centrifugally producing multi-component core-sheath composite fibers, using the apparatus described in this embodiment for centrifugally producing nanofiber yarns, is as follows:

[0098] PCL (polycaprolactone) was added to DCM (dichloromethane) to prepare spinning solution A with a concentration of 15 wt%, and PLGA (polylactic acid-glycolic acid copolymer) was added to DCM (dichloromethane) to prepare spinning solution B with a concentration of 12.5 wt%. Both spinning solutions were added to the supply device. When the spinning disc rotated at 6000 r / min, spinning solutions A and B were fed into the first and second spinning discs at flow rates of 15 ml / min and 12 ml / min, respectively. After drawing, twisting, and collection by the receiving plate, multi-component PCL / PLGA multi-component core-sheath composite fibers were produced. The receiving distance from the receiving plate to the spinning disc was 20 cm, and the inner diameter of the core-sheath spinnerets was 0.6 mm (i.e., the inner diameter of the spinning solution channels connected to the first and second spinning discs was 0.6 mm).

[0099] The average diameter of the prepared oriented multi-component PCL / PLGA composite fiber is 1.23 μm, and the average deflection angle of the fiber in the yarn along the yarn axis is 1.65°.

[0100] Example 5

[0101] A centrifugal device for producing nanofiber yarn is basically the same as in Example 1 (where the receiving device is a receiving plate), except that the spinnerets arranged on the circumference of the cylindrical tube I in this embodiment are all core-shaped spinnerets, and the number is 4.

[0102] A method for centrifugally producing oriented multi-component PCL / PLGA yarns, using the apparatus described in this embodiment for centrifugally producing nanofiber yarns, is as follows:

[0103] PCL (polycaprolactone) was added to DCM (dichloromethane) to prepare spinning solution A with a concentration of 15 wt%, and PLGA (polylactic acid-glycolic acid copolymer) was added to DCM (dichloromethane) to prepare spinning solution B with a concentration of 12.5 wt%. Both spinning solutions were added to a multi-component supply device. When the spinning disc rotation speed reached 6000 r / min, spinning solutions A and B were fed into the first and second spinning discs at flow rates of 15 ml / min and 12 ml / min, respectively. After drafting, bundling, and twisting, oriented multi-component PCL / PLGA yarn was finally obtained. The receiving distance from the receiving plate to the spinning disc was 20 cm, and the inner diameter of the core-shaped spinneret was 0.3 mm (i.e., the inner diameter of the spinning solution channel connected to the first and second spinning discs was 0.3 mm).

[0104] The obtained oriented multi-component PCL / PLGA yarn has an average diameter of 948.683 nm, a standard deviation of 70 nm, and an average fiber deviation angle of 4.65° along the yarn axial direction.

Claims

1. A method of centrifugally producing a nanofiber yarn, characterized by, In the process of preparing nanofiber by centrifugal spinning method, the horizontal outward airflow generated by the rotation of the spinning disc (4) is converted into a spiral airflow field by the device comprising the spinning disc (4), the receiving device, the driving device and the self-twisting device (5) to draft and twist the spinning solution sprayed from the spinneret to prepare nanofiber yarn. The spinning disc (4) comprises a vertical cylindrical tube I, the inside of which is provided with a spinning solution storage cavity, and the peripheral surface of the cylindrical tube I is provided with a spinneret in communication with the spinning solution storage cavity, and the liquid outlet direction of the spinneret is horizontal. The self-twisting device (5) comprises a horizontal cylindrical tube I, a horizontal cylindrical tube II, a rolling ball (5-1), a fan blade (5-4), a wind collecting cover and a wind concentrating cover (5-2). The cylindrical tube I is connected with the peripheral surface of the cylindrical tube I, the cylindrical tube I is sleeved on the cylindrical tube II, the rolling ball (5-1) is located between the cylindrical tube I and the cylindrical tube II, and the three constitute a bearing; the cylindrical tube II is sleeved on the spinneret, the fan blade (5-4) is fixed in the cylindrical tube II and is distributed around the spinneret. The wind collecting cover is located above the cylindrical tube I, the wind collecting cover is detachably connected with the cylindrical tube I, and the wind collecting cover is fixedly connected with the cylindrical tube I; the wind collecting cover is used for concentrating the horizontal outward airflow generated by the rotation of the spinning disc (4) into the cylindrical tube II. The wind concentrating cover (5-2) is located on the side of the cylindrical tube I away from the cylindrical tube I and is connected with the same; in the direction away from the cylindrical tube I, the size of the wind concentrating cover decreases; the end of the wind concentrating cover away from the cylindrical tube I is provided with a yarn outlet (5-3).

2. A process for the production of nanofibres by centrifugal spinning according to claim 1, characterized in that, The wind collecting cover is a vertical cylindrical tube II, the lower end of the cylindrical tube II is completely open, and the upper end is partially open to form a circular ring; the cylindrical tube II is coaxial with the cylindrical tube I and has the same outer diameter; the side wall of the cylindrical tube II is provided with an air inlet (5-5), and the air inlet (5-5) is in communication with the hollow part of the cylindrical tube I.

3. A method of producing nanofiber yarn by centrifugation according to claim 1, characterized in that, The number of the spinning solution storage cavities in the spinning disc (4) is n, n is a positive integer greater than or equal to 1; the number of the spinning solution channels in the spinneret is 1 or m, and the m spinning solution channels are respectively in communication with different spinning solution storage cavities, and m is a positive integer greater than 1 and less than or equal to n.

4. A process for the centrifugal production of nanofibrous yarn according to claim 3, characterized in that, When n>1, the spinneret is a skin-core spinneret (7) comprising one horizontal straight pipe a, one horizontal straight pipe b and one "L" shaped bent pipe c; the horizontal straight pipe a is sleeved on the horizontal straight pipe b and the inner diameter of the horizontal straight pipe a is greater than the outer diameter of the horizontal straight pipe b, one end of the horizontal straight pipe a and the horizontal straight pipe b is simultaneously connected with the peripheral surface of the cylindrical tube I, and the other end is flush; one end of the "L" shaped bent pipe c is connected with the peripheral surface of the cylindrical tube I, and the other end is connected with the horizontal straight pipe a; the horizontal straight pipe b and the "L" shaped bent pipe c are respectively in communication with different spinning solution storage cavities, the "L" shaped bent pipe c is in communication with the horizontal straight pipe a, and the horizontal straight pipe a is not in communication with the spinning solution storage cavity.

5. A process for producing nanofibrous yarn by centrifugation according to claim 3, characterized in that, n>1, the spinneret is an island-shaped spinneret (6), which comprises one horizontal straight pipe d and one or more than one "Z"-shaped bent pipe e, the "Z"-shaped bent pipe e is composed of an "L"-shaped bent pipe e1 and a horizontal straight pipe e2; one end of the horizontal straight pipe d and the "Z"-shaped bent pipe e is connected with the peripheral surface of the cylindrical barrel I, and the other end is flush; the horizontal straight pipe d is sleeved on the horizontal straight pipe e2, and the inner diameter of the horizontal straight pipe d is greater than the outer diameter of the horizontal straight pipe e2; the horizontal straight pipe d and the "Z"-shaped bent pipe e are respectively communicated with different spinning solution storage cavities.

6. A process for producing nanofibrous yarn by centrifugation according to claim 3, characterized in that, n=3; the spinning disc (4) further comprises a horizontal annular plate a, a horizontal annular plate b, a vertical cylindrical pipe III and a vertical cylindrical pipe IV; The annular plate a is arranged above the annular plate b with a spacing therebetween; the outer circle of the annular plate a is connected with the inner wall of the cylindrical barrel I, and the inner circle of the annular plate a is sleeved on the lower end of the cylindrical pipe III; the outer circle of the annular plate b is connected with the inner wall of the cylindrical barrel I, and the inner circle of the annular plate b is sleeved on the lower end of the cylindrical pipe IV, the cylindrical pipe IV penetrates into the cylindrical pipe III, and the upper ends of the two are flush with the cylindrical barrel I; The upper section of the cylindrical barrel I, the annular plate a and the cylindrical pipe III jointly form a spinning solution storage cavity I (13), the middle section of the cylindrical barrel I, the annular plate a, the cylindrical pipe III, the annular plate b and the cylindrical pipe IV jointly form a spinning solution storage cavity II (14), and the lower section of the cylindrical barrel I, the annular plate b and the cylindrical pipe IV jointly form a spinning solution storage cavity III (15); The upper section of the cylindrical barrel I constitutes a one-piece first spinning disc, the middle section of the cylindrical barrel I, the annular plate a and the cylindrical pipe III jointly constitute a one-piece second spinning disc, and the lower section of the cylindrical barrel I, the annular plate b and the cylindrical pipe IV jointly constitute a one-piece third spinning disc; the first spinning disc, the second spinning disc and the third spinning disc are detachably connected.

7. A process for producing nanofiber yarn by centrifugation according to claim 1, characterized in that, The device further comprises a liquid supply device (9), and the liquid supply device (9) comprises n liquid supply pipes which are respectively inserted into the n spinning solution storage cavities.

8. A process for producing nanofibrous yarn by centrifugation according to claim 1, characterized in that, The number of spinnerets is one or more, the number of self-twisters (5) is the same as that of spinnerets, and the two are one-to-one corresponding, and all the self-twisters (5) share the same wind collector.

9. A process for producing nanofibrous yarn by centrifugation according to claim 1, characterized in that, The receiving device is a cylindrical receiving plate (8), and the spinning disc (4) and the self-twister (5) are located in the receiving plate (8), and the receiving plate (8) is coaxial with the cylindrical barrel I; or the receiving device is a horizontal sheet-shaped spinning platform (3), and the spinning platform (3) is located below the spinning disc (4) and is connected with the lifting mechanism.

Images