CN110344127A - A kind of centrifugal spinning preparation method of porous Kynoar/polyethylene glycol oxide micro/nano-fibre - Google Patents

Abstract

The invention belongs to the technical field of porous micro/nano fibers, and in particular relates to a centrifugal spinning preparation method of polyvinylidene fluoride/polyethylene oxide (PVDF/PEO) micro/nano fibers. The method includes the following steps: (1) Preparation of centrifugal spinning solution: mix polyvinylidene fluoride (PVDF) and polyethylene oxide (PEO) and dissolve them in N‑N dimethylformamide (DMF), acetone and In water, a uniformly dispersed centrifugal spinning solution is obtained after stirring, wherein the mass concentrations of PVDF and PEO are 10-12wt% and 0.2-1wt% respectively; (2) Centrifugal spinning: the centrifugal spinning solution prepared in step (1) The solution was centrifugally spun to obtain polyvinylidene fluoride/polyethylene oxide (PVDF/PEO) micro/nanofibers with a porous structure. The morphology and structure of the polyvinylidene fluoride/polyoxyethylene micro/nanofiber membrane can be controlled by adjusting the content of polyethylene oxide.

Description

Centrifugal spinning of porous polyvinylidene fluoride/polyethylene oxide micro/nano fibers preparation method

technical field

The invention belongs to the technical field of porous micro/nano fiber preparation, in particular to a centrifugal spinning preparation method of polyvinylidene fluoride/polyethylene oxide (PVDF/PEO) micro/nano fiber.

Background technique

At present, the preparation of micro/nanofibers mainly focuses on the method of electrospinning. The following inherent defects in electrospinning limit the large-scale commercial use of this method: (1) a high voltage electric field needs to be applied during the preparation process; (2) ) The production efficiency is low; (3) the solution requires a certain proportion of solvent to make the solution have a certain conductivity and cause pollution. Therefore, in terms of cost, scale, and controllability research, there is still a long way to go from practicality and application requirements.

Centrifugal spinning overcomes the limitations encountered in the fabrication method of electrospun micro/nanofibers and enables the production of micro/nanofibers at high speed and low cost. This design does not need to apply a high-voltage electric field, can prepare polymer micro/nanofibers that are not constrained by conductivity, and its production efficiency has been greatly improved. The centrifugal spinning equipment has a simple structure, mainly composed of a motor, a spinning head, and a collecting rod. The spinning head is installed on the motor shaft, and the polymer solution is filled inside, and there are spinneret holes on the spinning head. When working, the motor is energized to rotate the spinning head, so that the spinning head rotates at a high speed, and the polymer solution is sprayed at the spinneret hole due to centrifugal force and moves between the collecting rod and the spinning hole to the collecting rod to form an ordered micro/nano fiber. The formation of micro/nano fibers by the polymer solution at the spinneret hole mainly goes through three stages: ①The polymer solution needs to have a certain viscosity, and when it reaches the spinneret hole when it rotates, it forms a Taylor cone; ②The polymer solution is simultaneously subjected to surface tension and centrifugal force Function, when the centrifugal force is greater than the surface tension, the polymer stretches to form fine micro/nano-scale fibers; ③The fibers rotate between the spinneret hole and the collecting rod under the action of centrifugal force, during which the solvent in the polymer solution Volatilize and get fibers that spin onto collection rods.

Contents of the invention

The invention provides a centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene (PVDF/PEO) micro/nano fibers with a porous structure.

The technical solution adopted by the present invention to solve its technical problems is:

A method for preparing porous polyvinylidene fluoride/polyoxyethylene micro/nano fiber by centrifugal spinning, the method comprises the following steps:

(1) Preparation of centrifugal spinning solution: mix polyvinylidene fluoride (PVDF) and polyethylene oxide (PEO) and dissolve them in N-N dimethylformamide (DMF), acetone and water, and obtain a uniform dispersion after stirring. Centrifugal spinning solution, wherein the mass concentrations of PVDF and PEO are 10-12wt% and 0.2-1wt% respectively;

(2) Centrifugal spinning: the centrifugal spinning solution prepared in step (1) is used for centrifugal spinning to obtain polyvinylidene fluoride/polyethylene oxide (PVDF/PEO) micro/nano fibers with a porous structure.

The preparation method of the invention is simple, and can rapidly and efficiently prepare polyvinylidene fluoride/polyoxyethylene micro/nano fibers. Due to the advantages of small fiber diameter, large specific surface area, and high porosity, micro/nanofibrous materials are widely used in tissue engineering scaffolds, drug delivery, filter media, artificial blood vessels, biochips, micro/nano sensors, optics, composite materials, etc. field. Micro/nanofibrous membranes have attracted the attention of many researchers due to the significant micro/nanoscale effects of micro/nanofibers. Under the requirements of the era of low-carbon economy, environmental protection, social security and human health, fiber/fabric is moving towards the research and development and development of high-tech fiber materials with higher technical content and less impact on resources, high-performance and functional high-tech fiber materials. Development in the direction of industrialization.

At present, the preparation of micro/nanofiber membranes mainly focuses on the method of electrospinning, and there is still a long way to go in terms of cost, scale, and controllability research from practical and application requirements. Therefore, in order to realize the controllable and large-scale preparation of micro/nanofibrous membranes, it is necessary to explore suitable new technologies and methods to reduce costs, expand scale, and improve preparation controllability. Based on the centrifugal spinning technology with industrial application prospects, it is a water-saving, energy-saving, green and non-polluting process, which can prepare micro/nano fibers from polymers, ceramics, and composite materials. Existing data have shown that the yield of micro/nanofibers by centrifugal spinning technology can be at least two orders of magnitude higher than that of electrospinning. Centrifugal spinning has opened up a new way for the preparation of micro/nano fibers, and has a good development prospect.

Preferably, in the solvent system of DMF, acetone and water, the mass ratio of the sum of DMF and acetone to water is 48-52:3.

Preferably, the mass concentration of PEO in the centrifugal spinning solution is 0.4-0.8 wt%.

As a preference, polyvinylidene fluoride (PVDF) molar mass M _W =600000g/mol, its chain structure formula is: Polyethylene oxide (PEO) molar mass M _W =2000000g/mol, its chain structure formula is:

As preferably, the preparation method of the centrifugal spinning solution described in step (1) is as follows: 1g of polyvinylidene fluoride (PVDF) and 0.06g of polyethylene oxide (PEO) are placed in a 20ml sample bottle, and 5.9 g acetone, 2.53g DMF and 0.51g water, seal the sample bottle with plastic wrap, raw tape and parafilm, heat to 40-50°C and stir for more than 12 hours to obtain a centrifugal spinning solution.

As preferably, the centrifugal spinning device that centrifugal spinning adopts comprises motor, spinning head and collecting rod, and spinning head is installed on the rotating shaft top of motor and is driven to rotate by motor, has the cavity that holds spinning liquid in spinning head, The top of the spinning head is provided with a liquid injection port, the side wall of the spinning head is provided with spinneret holes communicating with the cavity, and the collecting rods are arranged around the spinning head. During centrifugal spinning, the spinning head is driven by the motor to rotate, and the spinning solution is sprayed out from the spinneret hole of the spinning head, and moves between the spinneret hole and the collecting rod to be stretched, and at the same time, the solvent volatilizes to form fibers, which pass The collection rod receives the fibrous membrane. The motor speed is generally 5000-15000rpm/min. Preferably, the distance between the spinning head and the collecting rod is controlled at 10cm±2cm, and the diameter of the spinneret hole is 0.4mm-0.6mm. Preferably, the collecting rods are center-symmetrically distributed with the spinning head as the axis, and the number of collecting rods is 6-12. Preferably, the spinning head is made up of a spinning shell and a circular sealing ring, the spinning shell is a cylindrical structure with an open bottom, the bottom of the spinning shell extends outwards to form a ring-shaped rim, and a step is arranged in the middle of the ring-shaped rim, so The circular sealing ring cooperates with the step to seal the opening of the spinning shell, and the bottom of the circular sealing ring is flush with the bottom plane of the annular rim. Preferably, the spinneret is made of polytetrafluoroethylene. Preferably, the height difference between the spinning head and the top of the collecting rod is 1-2 cm. Preferably, the spinneret holes are located 2/3 from the bottom surface of the spinneret to the top surface, and 6-8 are arranged symmetrically on the same plane. Preferably, a pair of blades are arranged horizontally on the annular edge. When spinning, an upward airflow is formed so that the spun fibers are collected in the upper half of the collecting rod and not deposited at the bottom.

Preferably, during centrifugal spinning, the spinning speed is adjusted to 12000 rpm/min, the spinning liquid is sprayed out from the spinneret holes of the spinning head to form fibers, and the fibers are received by collecting rods.

A porous polyvinylidene fluoride/polyoxyethylene micro/nano fiber is prepared by the aforementioned method.

For the polystyrene micro/nano fiber membrane of the present invention, first, dissolve polyvinylidene fluoride (PVDF) and polyethylene oxide (PEO) in N-N dimethylformamide (DMF), acetone and water, and obtain a uniform dispersion after stirring The centrifugal spinning solution, and then the centrifugal spinning solution is obtained by centrifugal spinning. The centrifugal spinning preparation method of the micro/nanofiber membrane can be used for the preparation of porous micro/nanofibers, and has the following characteristics:

1. The preparation method of the present invention is simple and convenient, and the reaction conditions are easy to realize and control;

2. The morphology and structure of polyvinylidene fluoride/polyethylene oxide micro/nanofiber membrane can be controlled by adjusting the content of polyethylene oxide;

3. The fiber diameter of the micro/nano fiber membrane can be regulated by adjusting the spinning parameters such as: motor speed, spinneret diameter, and collecting rod distance;

4. The preparation of micro/nanofiber membranes by centrifugal spinning is more efficient and has a good room for expansion.

Description of drawings

Fig. 1 is the structural representation of centrifugal spinning device of the present invention;

Fig. 2 is the structural representation of spinning head among Fig. 1;

Explanation of symbols: 1 motor; 2 spinning head; 3 collecting rod; 4 blade; 5 fiber; 6 liquid injection port; 7 spinneret hole; 8 spinning shell;

Figure 3 is the SEM image of polyvinylidene fluoride micro/nanofibers (left × 500 times, right × 5000 times);

Fig. 4 is the SEM image (made in Example 1) of polyvinylidene fluoride/polyoxyethylene micro/nanofibers with a PEO content of 0.2wt% (left × 500 times, right × 5000 times);

Fig. 5 is the SEM image (made in Example 2) of polyvinylidene fluoride/polyoxyethylene micro/nanofibers with a PEO content of 0.4wt% (left × 500 times, right × 5000 times);

Fig. 6 is the SEM image (made in Example 3) of polyvinylidene fluoride/polyethylene oxide micro/nanofibers with a PEO content of 0.6wt% (left × 500 times, right × 5000 times);

Fig. 7 is the SEM image (made in Example 4) of polyvinylidene fluoride/polyoxyethylene micro/nanofibers with a PEO content of 0.8wt% (left × 500 times, right × 5000 times);

Fig. 8 is the SEM image (made in Example 5) of polyvinylidene fluoride/polyoxyethylene micro/nanofibers with a PEO content of 1wt% (left × 500 times, right × 5000 times);

Fig. 9 is the SEM image (made in Example 6) of polyvinylidene fluoride/polyoxyethylene micro/nanofibers with a PVDF content of 10wt% (left × 500 times, right × 5000 times);

Fig. 10 is the SEM image (made in Example 7) of polyvinylidene fluoride/polyoxyethylene micro/nanofibers with a PVDF content of 11wt% (left × 500 times, right × 5000 times);

Fig. 11 is the SEM image (made in Example 8) of polyvinylidene fluoride/polyoxyethylene micro/nanofibers with a PVDF content of 12wt% (left × 500 times, right × 5000 times);

Fig. 12 is the SEM image of DMF: acetone: water=35:15:1 polyvinylidene fluoride/polyoxyethylene micro/nanofiber (made in Example 9) (left × 500 times, right × 5000 times);

Fig. 13 is the SEM image of DMF: acetone: water=35:15:2 polyvinylidene fluoride/polyoxyethylene micro/nanofiber (made in Example 10) (left × 500 times, right × 5000 times);

Fig. 14 is the SEM image of DMF: acetone: water=35:15:3 polyvinylidene fluoride/polyoxyethylene micro/nanofiber (prepared in Example 11) (left × 500 times, right × 5000 times);

Fig. 15 is the SEM image of DMF: acetone: water=35:15:4 polyvinylidene fluoride/polyoxyethylene micro/nanofiber (made in Example 12) (left × 500 times, right × 5000 times);

Fig. 16 is the SEM image of DMF: acetone: water=30:20:3 polyvinylidene fluoride/polyoxyethylene micro/nanofiber (prepared in Example 13) (left × 500 times, right × 5000 times);

Fig. 17 is the SEM image of DMF: acetone: water=35:15:3 polyvinylidene fluoride/polyoxyethylene micro/nanofiber (prepared in Example 14) (left × 500 times, right × 5000 times);

Figure 18 is the SEM image of DMF:acetone:water=40:10:3 polyvinylidene fluoride/polyoxyethylene micro/nanofibers (prepared in Example 15) (left × 500 times, right × 5000 times).

Detailed ways

The technical solution of the present invention will be further specifically described below through specific examples. It should be understood that the implementation of the present invention is not limited to the following examples, and any modifications and/or changes made to the present invention will fall within the protection scope of the present invention.

In the present invention, unless otherwise specified, all parts and percentages are in weight units, and the equipment and raw materials used can be purchased from the market or commonly used in the field. The methods in the following examples, unless otherwise specified, are conventional methods in the art.

The centrifugal spinning device that following each embodiment centrifugal spinning adopts is as shown in Figure 1 and Figure 2, comprises motor 1, spinning head 2 and collecting rod 3, and spinning head is installed on the rotating shaft top of motor and is driven to rotate by motor, The spinning head has a cavity for containing the spinning liquid, the top of the spinning head is provided with a liquid injection port 6, the side wall of the spinning head is provided with a spinneret hole 7 communicating with the cavity, and the collecting rod surrounds the spinning head. circle set.

The distance between the spinning head and the collecting rod is controlled at 10cm±2cm, and the diameter of the spinneret hole is 0.4mm in this embodiment, but it can be adjusted to 0.5 or 0.6mm in actual production. In order to ensure better collection of fiber membranes, the height difference between the spinning head and the top of the collecting rod is 1-2 cm. The collecting rods are center-symmetrically distributed with the spinning head as the axis, and the number of collecting rods is 8.

The spinning head is made of polytetrafluoroethylene. The spinning head is composed of a spinning shell 8 and a circular sealing ring 9. The spinning shell is a cylindrical structure with an open bottom. The bottom end of the spinning shell extends outwards to form a ring-shaped edge 10, and a step 11 is arranged in the middle of the ring-shaped edge. The circular sealing ring cooperates with the step to seal the opening of the spinning shell, and the bottom of the circular sealing ring is flush with the bottom plane of the ring rim. The spinneret holes are located about 2/3 of the distance from the bottom surface of the spinneret to the top surface, and 8 holes are arranged symmetrically on the same plane.

A pair of blades 4 are also arranged along the horizontal direction on the annular edge. When spinning, an upward airflow is formed so that the spun fibers are collected in the upper half of the collecting rod and not deposited at the bottom.

During centrifugal spinning, the spinning head is driven by the motor to rotate, and the spinning solution is sprayed out from the spinneret hole of the spinning head, and moves between the spinneret hole and the collecting rod to be stretched, and at the same time, the solvent volatilizes to form fibers, which pass The collection rod receives the fibrous membrane. The motor speed is generally 5000-15000rpm/min.

Compared with electrospinning, centrifugal spinning equipment is simple, low in cost, and can spin higher concentration of spinning solution than electrospinning. Using this centrifugal spinning device is safer and more efficient in use; single nozzle electrospinning The productivity of the silk device is 1-100 mg/hour, and the productivity of centrifugal spinning can be increased by at least two orders of magnitude compared with electrospinning.

Example 1

A centrifugal spinning preparation method of porous polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF ) (wherein the molar mass M _W of PVDF =600000g/mol) and 0.02g polyethylene oxide (PEO) (wherein the molar mass M _W of PEO =2000000g/mol) are placed in a 20ml sample bottle, and 2.54g NN dimethyl Dimethyl formamide (DMF), 5.93g of acetone and 0.51g of water, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide .

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 2

A centrifugal spinning preparation method of porous polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF ) (wherein the molar mass M _W of PVDF =600000g/mol) and 0.04g polyethylene oxide (PEO) (wherein the molar mass M _W of PEO =2000000g/mol) are placed in a 20ml sample bottle, and 2.53g NN dimethyl Dimethyl formamide (DMF), 5.92g of acetone and 0.51g of water, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide .

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 3

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (wherein PVDF Molar mass M _W =600000g/mol) and 0.06g polyethylene oxide (PEO) (wherein the molar mass M _W of PEO =2000000g/mol) is placed in 20ml sample bottle, dropwise adds 2.53g NN dimethyl formamide ( DMF), 5.9g of acetone and 0.51g of water, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 4

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (wherein PVDF The molar mass M _W of =600000g/mol) and 0.08g polyethylene oxide (PEO) (wherein the molar mass M _W of PEO =2000000g/mol) are placed in the 20ml sample bottle, dropwise add 2.52g NN dimethyl formamide ( DMF), 5.89g of acetone and 0.51g of water, the sample bottle was sealed with raw tape, heated to 50°C, and stirred for 12 hours to finally obtain a uniformly dispersed centrifugal spinning solution of polyvinylidene fluoride/polyethylene oxide.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 5

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (the molar mass M _W of PVDF =600000g/mol) and 0.1g polyethylene oxide (PEO) (the molar mass M _W of PEO =2000000g/mol) were placed in a 20ml sample bottle, and 2.51g NN dimethyl Formamide (DMF), 5.88g of acetone and 0.51g of water, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Comparative example 1

A preparation method for centrifugal spinning of polyvinylidene fluoride micro/nano fibers, the specific steps are as follows:

(1) Accurately weigh 1g polyvinylidene fluoride (PVDF) (wherein the molar mass M _W of PVDF =600000g/mol) with an analytical balance and place it in a 20ml sample bottle, add dropwise 2.7g NN dimethylformamide (DMF) , 6.3g of acetone, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with evenly dispersed polyvinylidene fluoride.

(2) adopt the centrifugal spinning device shown in Fig. 1 and Fig. 2 to carry out centrifugal spinning, setting rotating speed is 12000rpm/min, the distance of collecting rod is 12cm, and the diameter of spinneret hole is 0.4mm, gets 5ml spinning solution sample in spinning In the head, the motor is turned on, and the SEM image of the prepared polyvinylidene fluoride micro/nanofibers is obtained through the collecting rod, as shown in Figure 3.

Implementation Effect

Scanning Electron Microscopy Observation of Surface Morphology of Polyvinylidene Fluoride/Polyethylene Oxide Fiber

The surface morphology of the fiber membranes prepared in Examples 1-5 was observed with an ULTRA55-36-73 field emission scanning electron microscope, and the SEM images of the fibers are shown in Figures 4-8, respectively. Comparing the SEM images, it can be found that compared with polyvinylidene fluoride fibers (Figure 3), the fibers added with PEO and water form a porous structure. Under the same spinning parameters, different contents of PEO are selected for spinning, as can be seen from the comparison SEM figure, when the PEO content is 0.2wt% (Fig. 4, made in Example 1), fibers with porous surface can be obtained; As the content of PEO increases, the porous structure of the fibers increases; however, when the content of PEO is 1 wt% (Fig. 8, prepared in Example 5), the fibers obtained are not uniform, easily entangled and difficult to spin. Therefore, when the PEO content is 0.6wt%, the porous polyvinylidene fluoride/polyethylene oxide fiber can be prepared, and the fiber diameter distribution is relatively uniform and the fiber surface has a porous structure.

Example 6

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (the molar mass M _W of PVDF =600000g/mol) and 0.06g polyethylene oxide (PEO) (the molar mass M _W of PEO =2000000g/mol) were placed in a 20ml sample bottle, and 2.53g NN dimethyl Formamide (DMF), 5.9g acetone and 0.51g water, the sample bottle was sealed with raw tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with evenly dispersed polyvinylidene fluoride/polyethylene oxide.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 7

A centrifugal spinning preparation method of polyvinylidene fluoride/polyethylene oxide micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1.1g polyvinylidene fluoride (PVDF ) (wherein the molar mass M _W of PVDF =600000g/mol) and 0.06g polyethylene oxide (PEO) (wherein the molar mass M _W of PEO =2000000g/mol) are placed in a 20ml sample bottle, and 2.53g NN dimethyl Dimethyl formamide (DMF), 5.89g acetone and 0.51g water, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide .

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 8

A centrifugal spinning preparation method of polyvinylidene fluoride/polyethylene oxide micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1.2g polyvinylidene fluoride (PVDF ) (wherein the molar mass M _W of PVDF =600000g/mol) and 0.06g polyethylene oxide (PEO) (wherein the molar mass M _W of PEO =2000000g/mol) are placed in a 20ml sample bottle, and 2.52g NN dimethyl Dimethyl formamide (DMF), 5.89g acetone and 0.51g water, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide .

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Implementation Effect

Scanning Electron Microscopy Observation of Surface Morphology of Polyvinylidene Fluoride/Polyethylene Oxide Fiber

The surface morphology of the fiber membranes prepared in Examples 6-8 was observed with an ULTRA55-36-73 field emission scanning electron microscope, and the SEM images of the fibers are shown in Figures 9-11 respectively. When the concentration of PVDF is 9%, the viscosity of the system is too low, the surface tension is too high, it is not easy to stretch, and the viscosity of the whole system is too low, it is difficult to form silk. When the amount of PVDF added is greater than 12%, the viscosity of the system is too high, and it is almost impossible to spray from the spinneret hole, so it cannot be formed into filaments. Comparing the SEM images, it is found that as the concentration of PVDF increases, the concentration of spinning solution increases, and the viscosity of the system also increases, resulting in a longer stress relaxation time for the solution, which limits the volatilization of the solvent and makes it more difficult to form filaments. Therefore, the concentration of PVDF is 10% (FIG. 9, prepared in Example 6), which is relatively moderate, and the diameter and thickness of the fibers are also relatively uniform.

Example 9

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (the molar mass M _W of PVDF =600000g/mol) and 0.06g polyethylene oxide (PEO) (the molar mass M _W of PEO =2000000g/mol) were placed in a 20ml sample bottle, and 2.63g NN dimethyl Formamide (DMF), 6.14g acetone and 0.17g water, the sample bottle was sealed with raw material tape, heated to 50°C, stirred for 12 hours, and finally a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide was obtained.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 10

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (the molar mass M _W of PVDF =600000g/mol) and 0.06g polyethylene oxide (PEO) (the molar mass M _W of PEO =2000000g/mol) were placed in a 20ml sample bottle, and 2.58g NN dimethyl Formamide (DMF), 6.02g of acetone and 0.34g of water, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 11

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (the molar mass M _W of PVDF =600000g/mol) and 0.06g polyethylene oxide (PEO) (the molar mass M _W of PEO =2000000g/mol) were placed in a 20ml sample bottle, and 2.53g NN dimethyl Formamide (DMF), 5.9g acetone and 0.51g water, the sample bottle was sealed with raw tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with evenly dispersed polyvinylidene fluoride/polyethylene oxide.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 12

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (the molar mass M _W of PVDF =600000g/mol) and 0.06g polyethylene oxide (PEO) (the molar mass M _W of PEO =2000000g/mol) were placed in a 20ml sample bottle, and 2.48g NN dimethyl Formamide (DMF), 5.79g of acetone and 0.67g of water, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Implementation Effect

Scanning Electron Microscopy Observation of Surface Morphology of Polyvinylidene Fluoride/Polyethylene Oxide Fiber

The surface morphology of the fiber membranes prepared in Examples 9-12 was observed with an ULTRA55-36-73 field emission scanning electron microscope, and the SEM images of the fibers are shown in Figures 12-15, respectively. When acetone: DMF: water is greater than 35:15:4, because the viscosity of the system is too small, the spinning solution is still in the form of droplets after being sprayed out from the hole, and cannot be drawn into filaments. Comparing the SEM images, it can be found that with the increase of water, the solvent volatilization rate decreases, the surface tension of the jet is more sufficient, and the stretching degree is greater. However, due to the reduction of volatile solvents, the viscosity decreases, the uniformity decreases, and finally the degree of fiber entanglement becomes larger. Comparing the SEM images, it can be seen that when the ratio is 35:15:3 (Figure 14, prepared in Example 11), the fiber diameter distribution is uniform and it is easier to form filaments. Therefore, the ratio of solvent acetone: DMF: water is 35:15:3.

Example 13

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (the molar mass M _W of PVDF =600000g/mol) and 0.06g polyethylene oxide (PEO) (the molar mass M _W of PEO =2000000g/mol) were placed in a 20ml sample bottle, and 3.37g NN dimethyl Formamide (DMF), 5.06g of acetone and 0.51g of water, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 14

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (the molar mass M _W of PVDF =600000g/mol) and 0.06g polyethylene oxide (PEO) (the molar mass M _W of PEO =2000000g/mol) were placed in a 20ml sample bottle, and 2.53g NN dimethyl Formamide (DMF), 5.9g acetone and 0.51g water, the sample bottle was sealed with raw tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with evenly dispersed polyvinylidene fluoride/polyethylene oxide.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Example 15

A centrifugal spinning preparation method of polyvinylidene fluoride/polyoxyethylene micro/nano fibers, the specific steps are the same as in Example 1, the difference is: (1) accurately weigh 1g of polyvinylidene fluoride (PVDF) with an analytical balance (the molar mass M _W of PVDF =600000g/mol) and 0.06g polyethylene oxide (PEO) (the molar mass M _W of PEO =2000000g/mol) were placed in a 20ml sample bottle, and 1.69g NN dimethyl Formamide (DMF), 6.75g of acetone and 0.51g of water, the sample bottle was sealed with raw material tape, heated to 50°C, and stirred for 12 hours to finally obtain a centrifugal spinning solution with uniform dispersion of polyvinylidene fluoride/polyethylene oxide.

(2) Adopt the centrifugal spinning device shown in Figure 1 to carry out centrifugal spinning, set the rotating speed as 12000rpm/min, the distance between the collecting rods is 12cm, and the diameter of the spinneret hole is 0.4mm, get 5ml spinning solution sample in the spinning head, Turn on the motor, and obtain porous polyvinylidene fluoride/polyethylene oxide micro/nanofibers through the collecting rod.

Implementation Effect

Scanning Electron Microscopy Observation of Surface Morphology of Polyvinylidene Fluoride/Polyethylene Oxide Fiber

The surface morphology of the fiber membranes prepared in Examples 13-15 was observed with an ULTRA55-36-73 field emission scanning electron microscope, and the SEM images of the fibers are shown in Figures 16-18, respectively. When the amount of solvent acetone is greater than 80% (the total amount of solvent is 100%), because the viscosity of the system is too small, the spinning solution is still in the form of droplets after being sprayed from the spinneret hole, and cannot be drawn into filaments. If the proportion of acetone is further reduced, the viscosity of the system will be too high and silk cannot be formed. In all solvent ratios, when DMF: acetone: water is 30:20:3, 35:15:3/40:10:3, silk can be formed better. Comparing the SEM images, it can be seen that with the reduction of the strong volatile solvent acetone, the jet flow increases during the spinning process, and the uniformity decreases, which eventually makes the degree of fiber entanglement larger, and the fibers are more easily entangled with each other. Therefore, it is better to choose DMF: acetone: water as 35:15:3 for the solvent ratio.

The embodiment described above is only a preferred solution of the present invention, and does not limit the present invention in any form. There are other variations and modifications on the premise of not exceeding the technical solution described in the claims.

Claims (9)

1. a kind of centrifugal spinning preparation method of porous Kynoar/polyethylene glycol oxide micro/nano-fibre, it is characterised in that should Method includes the following steps:

(1) preparation of centrifugal spinning solution: Kynoar (PVDF) is mixed with polyethylene glycol oxide (PEO) the two and is dissolved in N-N In dimethylformamide (DMF), acetone and water, finely dispersed centrifugal spinning solution is obtained after stirring, wherein PVDF and PEO Mass concentration is respectively 10-12wt% and 0.2-1wt%；

(2) centrifugal spinning: centrifugal spinning is carried out using centrifugal spinning solution made from step (1), obtains that there is porous structure Kynoar/polyethylene glycol oxide (PVDF/PEO) micro/nano-fibre.

2. centrifugal spinning preparation method according to claim 1, it is characterised in that: the dicyandiamide solution of DMF, acetone and water In, the mass ratio of DMF, the summation of acetone and water are 48-52:3.

3. centrifugal spinning preparation method according to claim 1, it is characterised in that: the quality of PEO in centrifugal spinning solution Concentration is 0.4-0.8wt%.

4. centrifugal spinning preparation method according to claim 1, it is characterised in that: step (1) the centrifugal spinning solution Specifically the preparation method is as follows: Kynoar and polyethylene glycol oxide are placed in sample bottle, N-N dimethyl is added into sample bottle Formamide, acetone and water, the mass ratio of N-N dimethylformamide, acetone and water is 15:35:3, and sample bottle raw material band is close Envelope is heated to 50-55 DEG C of stirring 24 hours or more, obtains centrifugal spinning solution.

5. centrifugal spinning preparation method according to claim 1, it is characterised in that: polyethylene glycol oxide (PEO) molal weight M_W =2000000g/mol, chain structure formula are as follows:Kynoar (PVDF) molal weight M_W= 600000g/mol, chain structure formula are as follows:

6. centrifugal spinning preparation method according to claim 1, it is characterised in that: in centrifugal spinning solution, PVDF content It is 0.6wt for 10wt%, PEO content.

7. centrifugal spinning preparation method according to claim 1, it is characterised in that: the centrifugal spinning dress that centrifugal spinning uses It sets including motor, spinneret and collects stick, spinneret is mounted on the shaft top of motor and is driven by a motor rotation, in spinneret With the cavity for accommodating spinning solution, liquid injection port is equipped at the top of spinneret, spinneret side wall is equipped with the spinneret being connected to the cavity Stick is collected around the circle setting of spinneret one in hole.

8. centrifugal spinning preparation method according to claim 7, it is characterised in that: when centrifugal spinning, by spinning revolving speed tune To 12000rpm/min, spinning solution is sprayed from the spinneret orifice of spinneret forms fiber, receives to obtain tunica fibrosa by collecting stick.

9. porous Kynoar/polyethylene glycol oxide micro/nano-fibre made from a kind of method described in claim 1.