Background technology
Electrostatic spinning technique is the effective ways of preparation polymer nano material, can obtain diameter at the one dimension fibre of tens nanometers to the hundreds of nanometer.Compare conventional fibre, nanofiber has higher high porosity and specific area.This makes electrostatic spinning technique obtain studying widely and using in filtration art.
Common single needle head electrospinning device mainly is made up of parts such as high voltage source, Spinning pumps, spinning syringe needle and collecting boaries.By high voltage source, between spinning syringe needle and collecting board, formed the high-voltage electrostatic field, the polymer solution droplets in spinning syringe needle exit is under the effect of electrostatic field, and shape can become taper, becomes " taylor cone ".Along with the increase of electric field force, " taylor cone " comes to a point gradually, and after cone-apex angle reached a critical value, vertex of a cone surface molecular was subjected to the surface tension that enough big electric field force overcomes solution, and polymer solution ejects from the vertex of a cone, forms injection stream.Electric field force stretches thousands of times to millions of times jet, and the diameter of jet is reduced to several microns to tens nanometers thereupon.Along with solvent evaporates, the fiber of gained finally is distributed on the collecting board desultorily, forms nano fiber non-woven fabric.
In the electrospinning process of single needle head, spinning efficiency very low (flow velocity of general spinning solution is 0.1-10mL/h) can't satisfy industrial production to the requirement of production efficiency.
Publication number is open day on May 16th, 2007 of CN1962966() patent application document a kind of spininess head electrospinning process is disclosed, can amplify the spinning of single needle head.Its shortcoming is that spinning efficiency is subject to the quantity of syringe needle, and syringe needle is easily blocked, will cause instability in industrial production, and extremely difficult cleaning.
Publication number is open day on October 18th, 2006 of CN1849418A() patent application document a kind of columniform axial symmetry spinning electrode is disclosed, its part immerses spinning solution, spinning electrode with electrode is formed electrostatic field, rotate around its symmetry axis by this electrode, spinning solution is fed in the electrostatic field continuously, reaches the purpose of continuous spinning.This invention has solved the interactive problem of electric field between the little and spininess head of syringe needle spinning amount well.And the cylindrical spinning electrode that should invent needs a bigger solution pool, so that cylindrical electrode can rotate freely therein and solution is constantly fed electric field.The shortcoming of this invention is that columniform electrode is in rotary course, directly bring remaining old solution after the spinning into solution pool and new soln mixing, this will greatly influence the polymer solution character of whole solution pool, accelerate the aging of solution in the pond, influence the spinning product quality.Concrete reason is as follows: the old solution after the spinning is different with new soln concentration, can influence solution concentration after the mixing, and the diameter of solution concentration and nanofiber, structure and performance is contacted directly, the instability that will bring the nanofiber product unusually of solution concentration; Old solution contacts with airborne steam, and SOLUTION PROPERTIES changes, and mixes with new soln again, can influence spinning quality equally; Old solution is partly worn out by electrode polarization, mixes with new soln to make new soln aging.
Publication number is that CN101755079A(was on June 23rd, 2010 in open day) patent application document announced a kind of spinning process that applies liquid-phase substrate at cable, introduced the mechanism that liquid-phase substrate applies and removes in this method, compared open day on October 18th, 2006 of patent application CN1849418A() the spinning process of cylinder electrode solved new and old solution and mixed the nanofiber product quality problem that has brought.The deficiency of this invention is that the used cable of spinning is little because of diameter, is in the part that spinning zone in the electrostatic field is positioned at the upper surface of cable, and this makes that the spinning region area is too small, causes spinning efficiency lower.
Summary of the invention
For overcoming the deficiencies in the prior art, the invention provides a kind of polymer solution electrostatic spinning assembly, apparatus and method, to solve the too small and lower problem of spinning efficiency that cause of polymer solution electrospinning device spinning region area.
First aspect of the present invention provides a kind of polymer solution electrostatic spinning assembly, comprising:
First electrode, and described first electrode second electrode and the spray body between described first electrode and described second electrode staggered relatively, wherein, described first electrode is plate electrode, and described spray body is used for to the described first electrode surface spray solution.
Further, described spray body is mobile on the plane that is parallel to described first electrode.
Further, described spray body is the 2-30 cel in the mobile speed range in the plane that is parallel to described first electrode.
Further, described spray body comprises the jet pipe that be arranged in parallel and the flat board that is positioned near the described first electrode side, wherein, the length direction of described jet pipe is parallel to the plane at the first electrode place, have on the tube wall of described jet pipe for the opening to the described first electrode spray solution, have the gap between described flat board and described first electrode surface.
Further, the cross section of described jet pipe is circle, ellipse or polygon.
Further, described opening comprises several nozzles.
Further, described opening comprises several apertures.
Further, described opening is the slit along described jet pipe length direction.
Further, the equal in length of the length of described slit and jet pipe.
Further, described spray body also comprises the scraper that is used for removing solution on described first electrode surface that be arranged in parallel with described jet pipe, and described jet pipe is between described flat board and described scraper.
Further, the surface configuration of described first electrode is polygon, and described polygonal size dimension is between 5~2000 millimeters, and perhaps the surface configuration of described first electrode is circular, and the diameter of described circle is between 5~2000 millimeters.
Further, the material of described first electrode is that metal material, alloy material or surface have the nonmetallic materials of the coat of metal.
Further, the material of described spray body is insulating materials.
Second aspect of the present invention provides a kind of polymer solution electrostatic spinning apparatus, comprising:
Power supply, fiber collecting parts, liquid-accumulating container and the communication means that connects liquid-accumulating container and spray body, comprise that also at least one filament spinning component, described filament spinning component adopt the described arbitrary spinning component structure in first aspect of the present invention, described collecting part is between described first electrode and institute's second electrode.
The 3rd aspect of the present invention provides a kind of polymer solution electrospinning process, comprising:
To the first electrode surface spray solution, be sprayed on solution on described first electrode surface under the effect of electrostatic field, form fiber, wherein, form electrostatic field between described first electrode and second electrode staggered relatively, and described first electrode is plate electrode.
Further, describedly after the first electrode surface spray solution, also comprise,
Strike off the solution that is sprayed on described first electrode surface, make it form the uniform solution layer of a layer thickness.
Further, describedly before the first electrode surface spray solution, also comprise, remove the surplus solution on described first electrode surface.
Further, also comprise, collect the fiber that forms.
A kind of polymer solution electrostatic spinning assembly provided by the invention, apparatus and method can significantly improve spinning efficiency.Wherein first electrode in the filament spinning component is plate electrode, and its electrode surface is the bigger plane of area.Polymer solution is sprayed on the surface of first electrode by spray body, this first electrode and staggered relatively with it to forming the spinning zone after electrode second electrifying electrodes, be sprayed on the solution spinning under the effect of electrostatic field on first electrode surface, form nanofiber.Because the area of first electrode is bigger, so the area in the spinning zone that forms is also bigger, can overcome in the prior art owing to the too small technical problem that limits spinning efficiency of the area in spinning zone.
The specific embodiment
For the purpose, technical scheme and the advantage that make the embodiment of the invention clearer, below in conjunction with the accompanying drawing in the embodiment of the invention, technical scheme in the embodiment of the invention is clearly and completely described, obviously, described embodiment is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills belong to the scope of protection of the invention not making all other embodiment that obtain under the creative work prerequisite.
In order to make those skilled in the art understand technical scheme of the present invention better, the present invention is described in further detail below in conjunction with the drawings and specific embodiments.
Embodiment one
Describe the structure of the polymer solution electrostatic spinning assembly of the embodiment of the invention one in detail in conjunction with Fig. 1 (1).Shown in Fig. 1 (1), this polymer solution electrostatic spinning assembly comprises first electrode 01, and described first electrode 01 second electrode 03 and the spray body 02 between described first electrode 01 and described second electrode 03 staggered relatively.Wherein, spray body 02 is used for the surface spraying polymer solution to first electrode 01, for the polymer solution electrostatic spinning has larger area spinning zone, present embodiment limits first electrode 01 and is plate electrode, present embodiment is not done restriction to the shape of second electrode 03, it can be cylinder electrode, also can be plate electrode, also can be the electrode of other shape.As long as can make and form electrostatic field between first electrode 01 and second electrode 03.Second electrode 03 is preferably the cylinder electrode that can rotate around symmetry axis, the electrostatic field that like this can disturbance between first electrode 01 and second electrode 03, forms, and the electrostatic field of this disturbance is favourable to causing spinning.In addition, the material of making first electrode 01 or second electrode 03 can be that metal, alloy or surface have the nonmetallic materials of the coat of metal.
Present embodiment does not limit the shape and size of first electrode 01.The surface of first electrode 01 can be arbitrary shapes such as polygon, circle, ellipse, in order to form thickness polymer foil solution relatively uniformly at first electrode surface, the surface be the size dimension of polygonal first electrode between 5~2000 millimeters, the surface is that the diameter of circular first electrode is between 5~2000 millimeters.Need to prove that the length of side on described polygonal every limit can equate, also can be unequal.More particularly, when first electrode was four distortion, it can be for growing the rectangle that limit and broadside do not wait.This size range can realize larger area spinning zone, can guarantee that again polymer solution in the spraying of first electrode surface evenly.
Described spray body 02 can be fixed, and for example is positioned at the central area of first electrode 01 and second electrode 03, in this position to the surperficial spray solution of first electrode 01.But, spray body 02 in the fixed position the surperficial spray solution to first electrode 01, have the inhomogeneous problem of spraying, especially when the surface area of first electrode 01 is relatively large, it is less that the amount of solution that is sprayed on the marginal surface zone of first electrode is understood relative central area.Further, in order to make the thickness that is sprayed on the polymer solution on first electrode surface even, described spray body 02 can be mobile on the plane that is parallel to described first electrode 01.When spray solution, spray body 02 moves to opposite side from a side of first electrode 01 with certain speed.Like this, can guarantee that polymer solution in the spraying of first electrode surface evenly.Further, different according to the kind of polymer solution and viscosity, the translational speed control of spray body 02 is in the scope of 2~30 cels.
Because be in the atmosphere of electrostatic field during this spray body 02 work, so this spray body 02 can not conduct electricity, this spray body 02 can be made by any non electrically conductive material.
Further, shown in Fig. 1 (1) and Fig. 1 (2), Fig. 1 (2) is the schematic diagram 1(1 of the embodiment of the invention one) A to view, described spray body 02 can comprise near the jet pipe 21 of first electrode, 01 side and dull and stereotyped 22, this jet pipe 21 and dull and stereotyped 22 opposing parallel settings, and the length direction of described jet pipe 21 is parallel to the plane at first electrode, 01 place, have on the tube wall of jet pipe 21 for the opening to first electrode, 01 spray solution, and the direction of this opening can make solution be sprayed on to greatest extent on the surface of first electrode 01 preferably towards the surface of first electrode 01 like this.When comprising a plurality of opening on the jet pipe, these a plurality of openings can be positioned on the straight line along its length of jet pipe 21 tube walls, also can irregularly distribute on jet pipe 21 tube walls.
Dull and stereotyped 22 and first electrode leaves gap 24 between 01 surface, utilize flat board 22 to strike off and be sprayed on first electrode, 01 lip-deep solution, make solution even at first electrode, 01 surface thickness everywhere, because have the gap 24 of certain size between first electrode, 01 surface and dull and stereotyped 22, the thickness that is sprayed on first electrode, 01 lip-deep layer of polymer solution can be controlled in this gap 24.Be readily appreciated that these gap 24 sizes can be the thickness of layer of polymer solution.
The jet pipe that described jet pipe 21 can have any shape, the cross section of this jet pipe can be circular, oval or any polygon.In addition, the opening on this jet pipe 21 can as shown in Figure 2, spray to polymer solution on the surface of first electrode 01 in jet pipe 21 by this aperture 211 for becoming several apertures 211 of at least one row.Present embodiment does not limit the shape of aperture 211, and the shape of this aperture 211 can be circular, square or other shape, also can be elongated strip shaped.
In addition, the opening on this jet pipe 21 can be a slit 211 ' that runs through these jet pipe 21 length directions, as shown in Figure 3.Opening on this jet pipe 21 can also be for comprising the sub-slit 211 ' of a plurality of interruptions along the jet pipe length direction ', as shown in Figure 4.By this slit 211 ' or 211 ' ' polymer solution is sprayed in jet pipe 21, spray on the surface of first electrode 01.
The opening of formula that in addition, the opening of this jet pipe 21 can also be nozzle 211 ' ' ', as shown in Figure 5, and nozzle 211 ' ' ' more is conducive on the surface that polymer solution is sprayed on first electrode 01 equably.
The polymer solution that the filament spinning component utilization flat board 22 that embodiment one provides will be sprayed on first electrode surface strikes off, make it become the uniform polymer solution thin layer of a layer thickness, like this under the effect of high-strength electrostatic field, first electrode, 01 lip-deep polymer foil solution forms the taylor cone of enormous amount at whole first electrode surface, has repulsive interaction between the taylor cone, make taylor cone evenly distribute and among a small circle, flow on the entire electrode surface, form good polymer nanofiber.Spray to first electrode from polymer solution and begin when the solution consumption of first electrode surface extremely can't be kept normal spinning, to be defined as the spinning cycle, in a spinning cycle, spinning process has experienced initiation spinning, normal spinning, can't keep normal spinning three phases, the state that wherein said normal spinning is easy to judge for those skilled in the art.Finishing all after dates of a spinning, to first electrode surface spraying new soln, then be defined as the beginning in next spinning cycle again.
When being in the continuous spinning state, the filament spinning component that embodiment one provides by spray body before first electrode surface spraying new soln can't with on the remaining old solution removal in a spinning cycle, cause new and old solution to mix, because remaining old solution is under effect of electric field, can part wear out, the mixing of new and old like this solution can influence spinning quality.For fear of the mixing of new and old solution, can the spraying new soln before, with last one the spinning cycle remnants old solution removal.
Embodiment two
Fig. 6 is the structural representation of the filament spinning component of the embodiment of the invention two, the filament spinning component of this filament spinning component and embodiment one has a lot of similarities, for the purpose of concise and to the point, present embodiment only focuses on to describe to its difference, the part identical with embodiment one is not described in detail, describes in detail and see also embodiment one.
Referring to Fig. 6, compared to embodiment one, the spray body 02 of the filament spinning component of present embodiment also comprises the scraper 23 that be arranged in parallel with described jet pipe 21, and this scraper 23 and dull and stereotyped 22 lays respectively at the both sides of jet pipe, in other words, jet pipe 21 is between flat board 22 and scraper 23.Scraper 23 can be with last residual solution removal of a spinning cycle, the new soln of spraying and mixing of old solution have been avoided, can not cause the aging of new soln, compared to the filament spinning component of embodiment one, the filament spinning component that present embodiment provides more can guarantee the quality of spinning.
Based on the filament spinning component of embodiment one or embodiment two, the present invention also provides a kind of polymer solution electrostatic spinning apparatus.
Embodiment three
Fig. 7 is the device for spinning schematic diagram of the embodiment of the invention three.This device for spinning comprises first electrode 01, second electrode 03, spray body 02, high voltage source 04, fiber collecting parts 05, liquid-accumulating container 06 and the communication means 07 that is communicated with liquid-accumulating container 06 and spray body 02.Wherein, first electrode 01, second electrode 03 and spray body 02 are formed filament spinning component, the structure employing embodiment one of this filament spinning component or the structure of the filament spinning component that embodiment two provides.
During spinning, first electrode 01 and second electrode 03 are connected the both positive and negative polarity of high voltage source 04 respectively, or first electrode 01 connects one of them electrode and second electrode, 03 ground connection of high voltage source, to form high-strength electrostatic field between first electrode 01 and second electrode 03.
Fiber collecting parts 05 are between first electrode 01 and second electrode 03, generally, fiber collecting parts 05 are the parts (as panel) of a surfacing, the fiber 08 that generates between first electrode 01 and second electrode 03 can accumulate on the fiber collecting parts 05, forms one deck fibrage.Wherein, fiber collecting parts 05 can move by side to opposite side from one of spinning zone along the plane translation at its place, collect the fiber 08 of generation.Wherein, the direction that the direction that fiber collecting parts 05 move and spray body 02 move can be parallel, can be vertical, also can become unspecified angle.
By communication means 07 liquid-accumulating container 06 and spray body 02 is communicated with, has bigger pressure when making solution spraying, polymer solution is sprayed smoothly, can also a force (forcing) pump be installed in communication means 07, be used for increasing the pressure of solution.
Device for spinning provided by the invention can also comprise a plurality of (at least two) described filament spinning component.By the spinning zone that a plurality of filament spinning components are formed, compared to the spinning zone that single filament spinning component is formed, its spinning efficiency can significantly improve.Owing to comprise that the device for spinning of a plurality of filament spinning components is identical substantially with the structure of the device for spinning that comprises a filament spinning component.Filament spinning component is together in parallel forms a bigger spinning zone, and then is connected with other parts in the device, and its connected mode is identical with the connected mode of single filament spinning component.Those skilled in the art are easy to expect contain the embodiment of the device for spinning of a plurality of filament spinning components on the basis of embodiment three.For the purpose of concise and to the point, no longer the device for spinning that contains a plurality of filament spinning components is described in detail at this.
Based on the device of embodiment three described polymer solution electrostatic spinnings, the present invention also provides a kind of polymer solution electrospinning process.
Embodiment four
Fig. 8 is the flow chart of steps of the method for present embodiment, and this spinning process may further comprise the steps:
S801, to the first electrode surface spray solution:
Adopt the pressure of the supply solution of this area routine that solution is pushed into spray body 02 by liquid-accumulating container 06 via communication means 07, via jet pipe 21 polymer solution is sprayed on first electrode, 01 surface then.In order to obtain thickness solution layer comparatively uniformly on first electrode, 01 surface, spray body is preferably along moving with the plane at first electrode, 01 place.
Need to prove that generally speaking, polymer solution has bigger viscosity, successfully from jet pipe, spray in order to make polymer solution, preferably adopt force (forcing) pump to increase the pressure of solution.And when the pressure of polymer solution increased, polymer solution was difficult for stopping up the opening of jet pipe.
S802, strike off the solution that is sprayed on described first electrode surface, make it form the uniform solution layer of a layer thickness:
When spray body moved, in jet pipe ejection solution, and then dull and stereotyped 22 can strike off the solution that is sprayed on first electrode surface, makes it form the uniform solution layer of a layer thickness.
S803, solution layer form fiber under the effect of electrostatic field:
First electrode and second electrode are connected to the two poles of the earth of high voltage source, or a wherein electrode and second electrode, 03 ground connection of first electrode, 01 connection high voltage source, between first electrode and second electrode, form high-strength electrostatic field, be sprayed on solution layer on first electrode surface under the effect of electrostatic field, spinning forms fiber.
Particularly, the occurrence of described power supply and electric power outputting current can be referring to table 1.
S804, with fiber collecting on the fiber collecting parts:
By the spinning zone, the fiber of formation can be collected on these fiber collecting parts 05 fiber collecting parts 05 between first electrode 01 and second electrode 03 with certain speed and direction.Wherein, the direction that fiber collecting parts 05 move can be parallel with the direction that spray body 02 moves, also can be perpendicular.In addition, the speed that these fiber collecting parts 05 move is that those skilled in the art select according to required fiber layer thickness, and the speed of speed has determined the size of collected nanofiber layer thickness.Be collected in microstructure such as the Fig. 9 and shown in Figure 10 of the fiber on the fiber collecting parts 05.
From Fig. 9 and Figure 10, as can be seen, the nanofiber diameter that this spinning process obtains can reach 90nm or 500nm.So, can infer that the nanofiber that this spinning process obtains can reach the demand of different-diameter.
In order to be well understood to the specific embodiment of polymer solution electrospinning process of the present invention.Can be referring to table 1.Table 1 lists the size of shape, spray body gait of march, first electrode of relation, the opening of the spray body direction of motion and fiber collecting component movement direction and supply voltage and output current to the influence of spinning efficiency.
Table 1:
In the electrostatic spinning process of reality, jet pipe 21 in the spray body 02 of motion is to first electrode, 01 surperficial spray solution the time, dull and stereotyped 22 can strike off the solution that is sprayed on first electrode surface, simultaneously, if first electrode has residual solution on 01 surface, scraper 23 can be removed residual solution.At spray body 02 during at the spinning regional movement, each parts in the spray body 02 comprise jet pipe 21, dull and stereotyped 22 and scraper 23 can work simultaneously, and do not need to carry out separately.
The above only is preferred embodiment of the present invention; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention; can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.