CN106591966B

CN106591966B - Electrohydrodynamic preparation method of silk particle parallel micro-nano structure

Info

Publication number: CN106591966B
Application number: CN201611021571.9A
Authority: CN
Inventors: 余灯广; 张玲玲; 张瑶瑶; 郑招斌; 张曼
Original assignee: University of Shanghai for Science and Technology
Current assignee: University of Shanghai for Science and Technology
Priority date: 2016-11-21
Filing date: 2016-11-21
Publication date: 2020-11-24
Anticipated expiration: 2036-11-21
Also published as: CN106591966A

Abstract

The invention relates to an electrohydrodynamic preparation method of a filament particle parallel micro-nano structure, which combines nano fibers of 'filaments' and micron particles of 'particles' together by electrohydrodynamic preparation to form a parallel structure characteristic. The preparation process is simple, single step is effective, and the prepared silk grain side-by-side structure product is clear in structure and uniform in distribution. The preparation method of the parallel micro-nano structure can provide an effective tool for the development of a plurality of novel functional materials.

Description

Electrohydrodynamic preparation method of silk particle parallel micro-nano structure

Technical Field

The invention relates to a micro-nano material processing technology, in particular to an electrohydrodynamic preparation method of a silk grain parallel micro-nano structure.

Background

The electrohydrodynamic method uses high-voltage static electricity as energy and utilizes the interaction between the high-voltage static electricity and fluid to prepare solid materials. The method mainly comprises a high-voltage electrostatic spinning technology (electrospinning), a high-voltage electrostatic spraying technology (electrospraying) and a jet printing technology. The high-voltage electrostatic spinning technology (electrospinning) is a top-down (top-down) nano manufacturing technology, jet flow is formed by overcoming the liquid surface tension and the viscous elasticity of liquid drops at the tip of a nozzle through external electric field force, the atomized liquid jet flow is bent, drawn and split at high frequency under the combined action of electrostatic repulsion force, coulomb force and surface tension, and is drawn by tens of millions of times within tens of milliseconds, and nano-scale fibers are obtained at a receiving end through solvent volatilization or melt cooling. The high-voltage electrostatic spraying technology applies certain voltage to working fluid, so that the working fluid is rapidly split and atomized under a high-voltage electrostatic field through electrostatic repulsive force to generate a large surface area, and solid particles are prepared through rapid volatilization of a solvent in atomized liquid drops. The electrohydrodynamic technological process is simple, convenient to operate and control, wide in material selection range and strong in controllability, is considered to be a method most likely to realize continuous industrial production of the micro-nano material, and the functional micro-nano material prepared by applying the technology has a good prospect.

There are many documents on the electrospinning technology to prepare nanofibers, and there are also many reports on the electrospraying to prepare polymer particles, but there are few studies on the combination of the structural characteristics of the two materials. Because the electrospun fiber is generally positioned at a nano level, and the electrospray particles are more positioned at a micron level, the combination of the electrospun fiber and the electrospray particles can enable the nanofiber material and the micron particle material to generate the synergistic effect of the biological structure level, endow the micro-nano structure product with better performance and composite function, and even promote the micro-nano structure product to generate new functional application.

Disclosure of Invention

The invention provides an electrohydrodynamic preparation method of a filament particle parallel micro-nano structure aiming at the problem that nano fibers and polymer particles are combined to form a micro-nano structure, wherein nano fibers which are filaments and micro particles which are particles are combined together by electrohydrodynamic preparation to form a parallel structure characteristic.

The technical scheme of the invention is as follows: an electrohydrodynamic preparation method of a silk grain parallel micro-nano structure specifically comprises the following steps:

1) building a preparation device: the eccentric sleeve nozzle is internally provided with two large and small parallel capillaries, the small capillaries are arranged in the large capillaries, the walls of the capillaries are tangent, and fluid in an injector fixed on a first fluid injection pump is connected with the inlets of the small capillaries in the eccentric sleeve nozzle through a high-elasticity silica gel hose; the fluid in the injector fixed by the second fluid injection pump is directly connected with the large capillary tube inlet of the eccentric sleeve nozzle, the high-pressure generator is connected with the eccentric sleeve nozzle, the lower end of the outlet of the eccentric sleeve nozzle is provided with a receiving plate, and the receiving plate is an aluminum foil-wrapped hard board;

2) preparing polymer fluid with good spinning performance, and injecting the polymer fluid into an injector fixed on a first fluid injection pump;

3) preparing polymer fluid or micromolecule fluid without spinning performance, and injecting the polymer fluid or the micromolecule fluid into an injector fixed on a second fluid injection pump;

4) and starting the high-voltage generator, controlling two injection pumps to control the flow rates of two fluids in the eccentric sleeve nozzle, and generating a product with a structure of parallel nano fibers and micron particles at the outlet of the eccentric sleeve nozzle under the action of high-voltage static electricity, and receiving the product by the receiving flat plate.

The steps 2) and 3) of the nanofiber and microparticle side-by-side structure product are prepared as follows: putting 10 g of ethyl cellulose into 100 g of ethanol to prepare non-spinnable polymer fluid, and putting 7 g of polyvinylpyrrolidone and 0.01 g of methylene blue into 100 g of ethanol to prepare spinnable polymer fluid; the control requirement of the step 4) after the blending is as follows: the flow rates of the two flows are both 1.0mL/h, the distance between the receiving flat plate and the outlet of the spray head is 15cm, the voltage of a high-voltage generator is 14kV, the ambient temperature is 24 +/-2 ℃, and the ambient humidity is 55 +/-5%.

When the product with the nanofiber and microparticle structure is a product with a polymer/lecithin silk particle parallel micro-nano structure, the preparation of the two streams of the fluid in the steps 2) and 3) is as follows: adding 7 g of polyvinylpyrrolidone and 0.01 g of methylene blue into 100 g of ethanol to prepare spinnable polymer fluid; dissolving 20 g of soybean lecithin in 100 g of dichloromethane to prepare a small molecular fluid;

the control requirement of the step 4) after the blending is as follows: the flow rates of the two flows are both 1.0mL/h, the distance between the receiving flat plate and the outlet of the spray head is 15cm, the voltage of a high-voltage generator is 14kV, the ambient temperature is 24 +/-2 ℃, and the ambient humidity is 55 +/-5%.

The invention has the beneficial effects that: the electrohydrodynamic preparation method of the silk grain parallel micro-nano structure has the advantages of simple preparation process, single step effectiveness, clear structure of the prepared silk grain parallel structure product and uniform distribution. The preparation method of the parallel micro-nano structure can provide an effective tool for the development of a plurality of novel functional materials.

Drawings

FIG. 1 is a schematic diagram of a filament-particle parallel micro-nano structure;

FIG. 2 is a diagram of an implementation device of the electrohydrodynamic preparation method of the silk grain parallel micro-nano structure of the invention;

FIG. 3 is a schematic cross-sectional view of an eccentric sleeve injector head according to the present invention;

FIG. 4 is a photograph of an electrohydrodynamic preparation process of a silk-grain-juxtaposed micro-nano structure of the present invention;

FIG. 5 is a scanning electron microscope image of the present invention with the filament particle-juxtaposed micro-nano structure;

FIG. 6 is a transmission electron microscope image of the silk particle-juxtaposed micro-nano structure of the present invention.

Detailed Description

The filament particle parallel micro-nano structure is shown in figure 1, wherein a component 2 is silk nano fibers, and a component 1 is particle micro particles, and the silk particles and the particle micro-nano structure are adhered together to form a parallel structure characteristic. The structural features can integrate the common efficacy of the micro-materials and the nano-materials, and can also integrate the common properties of the particulate materials and the fibrous membrane materials.

Assembling a device in a parallel electrohydrodynamic preparation method: an implementation device of the electrohydrodynamic preparation method of the silk particle parallel micro-nano structure is shown in fig. 2 and comprises the following steps: a high voltage generator 1; a fluid injection pump 2; a fluid injection pump 3; a product receiving plate 4; an eccentric sleeve nozzle 5; a high-elasticity silica gel hose 6; a fluid injector 7 and a fluid injector 8. The eccentric sleeve nozzle 5 has two parallel large and small capillaries, and the small capillaries are in the large capillaries and the walls of the capillaries are tangent as shown in the cross-sectional view of the eccentric sleeve nozzle in fig. 3. The fluid in an injector 8 fixed on the fluid injection pump 3 is connected with the inlet of a small capillary tube in the eccentric sleeve nozzle 5 through a high-elasticity silica gel hose 6; the fluid in the injector 7 fixed by the fluid injection pump 2 is directly connected with the large capillary inlet of the eccentric sleeve nozzle 5. The high-pressure generator 1 is connected with an eccentric sleeve nozzle 5. The lower end of the outlet of the eccentric sleeve nozzle 5 is provided with a receiving plate 4, and the receiving plate 4 is a hardboard wrapped by aluminum foil.

Preparation of two working fluids: 10 g of ethylcellulose were placed in 100 g of ethanol and sprayed as a non-spinnable polymer working fluid, 7 g of polyvinylpyrrolidone and 0.01 g of methylene blue were placed in 100 g of ethanol and sprayed as a spinnable polymer fluid.

Implementation of the parallel electrohydrodynamic preparation method: the two working fluids are respectively filled into corresponding syringes, are fixed on corresponding injection pumps according to embodiment 1, and are communicated with an eccentric sleeve nozzle and a high-voltage electrostatic generator.

The parallel electrohydrodynamic method is implemented according to the following process condition parameters: the flow rates of both streams were 1.0mL/h, the distance of the receiver plate from the spinneret was 15cm, and the voltage was 14 kV. The ambient temperature is (24 +/-2) DEG C, and the ambient humidity is 55 +/-5%. The product was collected through a grounded aluminum foil wrapped cardboard. Under the above working conditions, the electrospinning process was photographed in situ with magnification, and the result is shown in fig. 4, which shows a typical electrohydrodynamic process, i.e. an unstable region from taylor cone, straight jet to high frequency stretching. Under the indication of indicator methylene blue, the composite Taylor cone of the side-by-side structure is clear and distinguishable.

Analyzing and characterizing the silk particle parallel micro-nano structure: the micro-nano structure prepared in example 3 was subjected to surface metal spraying by using a field scanning electron microscope and observed, and the result is shown in fig. 5. The prepared silk grain parallel micro-nano structure is uniformly distributed. Wherein the fiber side is in good linear state with diameter of 74 + -9 nm, and the particle side is in circular state with diameter of 2.1 + -0.4 μm. The prepared structure was observed with a high-resolution projection electron microscope, and the result is shown in fig. 6, in which the microparticles and the nanofibers were tightly bonded together.

Preparing a polymer/lecithin silk particle parallel micro-nano structure: 7 g of polyvinylpyrrolidone and 0.01 g of methylene blue are placed in 100 g of ethanol and sprayed to form a spinnable polymer fluid. Working fluid (this is a small molecule fluid) was prepared by dissolving 20 g of soybean lecithin in 100 g of methylene chloride. They were loaded into respective syringes and fixed to respective syringe pumps according to example 1, and the eccentric canula nozzle and the high-voltage electrostatic generator were connected. The parallel electrohydrodynamic method is implemented according to the following process condition parameters: the flow rates of both streams were 1.0mL/h, the distance of the receiver plate from the spinneret was 15cm, and the voltage was 14 kV. The ambient temperature is (24 +/-2) DEG C, and the ambient humidity is 55 +/-5%. And collecting the product through a grounded aluminum foil wrapping paper board to obtain a polymer/lecithin silk grain parallel micro-nano structure product.

The invention is characterized in that the parallel structure is formed by automatically and uniformly mixing nano fibers and micro particles in the preparation process; one side of the micron particles in the parallel structure is bonded on the other side of the nano-fiber, and the micron particles and the nano-fiber form a complete product together; the structure is prepared by adopting an eccentric sleeve as a spray head to implement an electrohydrodynamic process; one of the two parallel streams is a polymer solution with good spinning performance, and the other stream is a polymer solution or a small molecule solution without spinning performance. The parallel structure of the silk grains adopts an aluminum foil flat plate for receiving.

Claims

1. An electrohydrodynamic preparation method of a silk grain parallel micro-nano structure is characterized by comprising the following steps:

2. The electrohydrodynamic preparation method of the filament-particle-juxtaposed micro-nano structure of claim 1, wherein the steps 2) and 3) of the nanofiber and microparticle-juxtaposed product are as follows: putting 10 g of ethyl cellulose into 100 g of ethanol to prepare non-spinnable polymer fluid, and putting 7 g of polyvinylpyrrolidone and 0.01 g of methylene blue into 100 g of ethanol to prepare spinnable polymer fluid; the control requirement of the step 4) after the blending is as follows: the flow rates of the two flows are both 1.0mL/h, the distance between the receiving flat plate and the outlet of the spray head is 15cm, the voltage of a high-voltage generator is 14kV, the ambient temperature is 24 +/-2 ℃, and the ambient humidity is 55 +/-5%.

3. The electrohydrodynamic preparation method of the silk-particle-parallel micro-nano structure according to claim 1, wherein the steps 2) and 3) are as follows when the nanofiber and microparticle structure product is a polymer/lecithin silk-particle-parallel micro-nano structure product: adding 7 g of polyvinylpyrrolidone and 0.01 g of methylene blue into 100 g of ethanol to prepare spinnable polymer fluid; dissolving 20 g of soybean lecithin in 100 g of dichloromethane to prepare a small molecular fluid;