Middle-scale Nanofiber Electrospinning Production Line MF01-002

Qingzi Nano’s MF01 is an equipment of series of nanofiber production line, including needle spinning( MF01-001 and MF01-002) and needle-free spinning (MF01-003 and MF01-004) series. It is based on electrospinning technology to produce nanofiber membrane in high efficiency and quantity production, which can meet the growing need for nanofiber applications and achieve industrial benefits.

Automatic roll-to roll system;

Precious feeding system: corrosion resistance, high-voltage resistance;

Temperature and humidity controllable;

Safeguard system;

Small risk with big return;

Stable production, easy to maintain, can be copied to expand productivity as a unit;

Technical electrospinning multi-nozzle array system: 128 needles;

Speed of roll-to roll: 0-5m/min, adjustable;

Continuous operation time: ≥ 8 hours;

Electrospinning high-voltage supply: 0-50KV, adjustable;

Effective width of nanofiber layer: 660mm

What Is The Structure Of the Centrifugal Electrospinning Setup?

In most centrifugal spinning systems, the polymer solution or melt is injected into the spinneret, which is perforated with multiple nozzles around the sidewall and connected to the motor on the other side as shown in Fig. 10.3. Then liquid jets are formed at the nozzle tips or the polymer pathway of the spinning head when the centrifugal force overcomes the surface tension of the spinning fluid. After the liquid jets come out of the nozzle tips, the centrifugal force and the air frictional force can elongate and solidify the liquid jets into a fibrous morphology with solvent evaporation. The macromolecular chain entanglements of the polymer lead to a viscoelasticity, which enables continuous jet formation. Therefore, a good collaboration between rotational speed and solution concentration can prevent jet breakup and bead formation.

How Nanofluidic Chips Were Fabricated By Near-field Electrospinning (NFES)

In recent years, nanofluidic chips have attracted lots of interests because of their high integration. As a typical technology with great compatibility and low cost, NFES has displayed great potential in the preparation of nanofluidic chips. In 2007, Lee et al. demonstrated the integration of chip-to-chip fluidic connectors, as shown in Fig. 9.21A, via NFES to the wire bonding technique in integrated circuit manufacturing. Orderly direct-written fibers were deposited with position precision of better than 10 mm to connect two separated chips, which served as the sacrificial material. Then, the coating process and sacrificial layer etching process were followed to fabricate micro/nanofluidic channels with inner diameter about 0.05-5 mm. Based on NFES, Wang et al. presented complicated wave-shape and grid pattern channels under the predesigned movement of substrate, of which the fabrication process is shown in Fig. 9.21B. Fuh utilized NFES to generate well-aligned and addressable nanofiber arrays, which were used as the master to prepare polydimethylsiloxane stamps. The nanofluidic channel was sealed by bonding with the same polymer or a microscope slide, as shown in Fig. 9.21C, which shows reliable and repeatable performance in the nanofluidic test.

How To Make Direct-written 3D Structures

Many complex 3D nanofibrous structures with high aspect ratio have been built based on NFES. Lee and Kim proposed a method to fabricate a freestanding nanowall (Fig. 9.20C) with direct-written nanofibers. To control the whipping instability of the electrical nanojets, a conductive microline on the insulating plate was used as the grounded collector to focus the electrical field. In this way, a jet with 180 nm diameter and 30 mm/s velocity can be used to construct a nanowall of 4.5 mm height and 220 mm length. Han et al. applied electrohydrodynamic printing for 3D microstructures. A droplet will print on the top of the previous droplet once the nozzle is fixed at a certain location, which results in a high aspect ratio of pillars. A circular tube with a height of 40-60 mm and wall thickness of 6 mm was printed, as shown in Fig. 9.20D. Compared with traditional 3D printing, the resolution was improved by 1 or 2 orders of magnitude.

How To Use Auxiliary Methods To Print 2D Complex Patterns

To print 2D patterns with complex contours, some methods have been suggested to ameliorate NFES. Zhu et al. designed an auxiliary electrode applied with an AC electrical field to regulate the deposition of wavy fibers in NFES, as illustrated in Fig. 9.19A. An AC voltage was applied to control the wavy amplitude and generating frequency of the fibers. The results show that a continuous wavy fiber can be deposited on the collector when the distance between nozzle and collector increases to 4 mm. The amplitude of wavy fibers increases with increasing AC voltage and the frequency of wavy fibers equals the AC frequency. Lee et al. used a guide ring located 0.03 mm below the nozzle and a pin-type electrode that served as the grounded electrode to focus the jet on the substrate, as shown in Fig. 9.19B. The setup is usable for increasing the axial electrical field without a significant change in the radial electrical field, which can improve the stability of a microsized jet in the cone-jet mode and reduce the breakup of the jet. In this way, various complex 2D patterns can be printed onto photographic paper with average line width of 130 mm.

How To Do SHEATH GAS-ASSISTED ELECTROHYDRODYNAMIC DIRECT WRITING

To further improve the deposition behavior, a core-shell-shaped spinneret has been designed and in this design a sheath gas goes out from the peripheral channel to travel around the jet. The sheath gas provides an additional stretching and focusing force on the ejecting jet, which is beneficial to overcoming interference from the surrounding environment and gaining precise micropatterns. He et al. utilized sheath gas to fabricate micro/nanostructures under a lower applied voltage. With the help of the stretching force stemming from the sheath gas, the initiation voltage and sustaining voltage decrease obviously. Low applied voltage is helpful to restrain the instability of the printing process and promote the integration fabrication of micro/nanodevices. The average diameter of the micro/nanostructure decreases from 21.58 mm to 505.58 nm when the assisted gas pressure increases to 50 kPa. In addition, based on the same setup, Zheng et al. investigated the patterned deposition behavior of a charged jet. With the help of a sheath gas, the surrounding interference can be weakened and the charged jet can be free from the influence of the microstructures. Fig. 9.16 shows that precise complex micropatterns such as parallel lines and grids can be direct written with position precision to less than 5 mm.

How To Make Micro/nanofibrous Structures Direct Written On An Insulating Substrate

As a mass of charge accumulates on the deposited nanofiber, it is difficult to achieve patterned deposition on the insulating substrate. Zheng et al. demonstrated direct writing of orderly micro/nanofibrous structures on a flexible insulating polyethylene terephthalate (PET) substrate utilizing an AC electrical field. The charge transfer characteristics in the jet are changed and the Coulomb repulsive force from the residual charges on the deposited structure is reduced with the help of the applied AC voltage, as shown in Fig. 9.11A and B. Thus a stable jet can be built up and orderly structures, as shown in Fig. 9.11C, can be collected on the PET substrate. From the experimental results, the minimum motion velocity of substrate required to direct write a straight line is 700 mm/s and the line widths of direct-written fibrous structures are in the range of 10-40 μm.

How to Do ALTERNATING CURRENT ELECTROHYDRODYNAMIC DIRECT WRITING

Due to the strong Coulomb repulsive force, direct writing of conductive patterns on an insulating substrate is of great difficulty for NFES. An AC electrical field has been introduced to change the transfer characteristics of the charge along the jet, by which the Coulomb repulsive force can be weakened and the stability of the charged jets can be improved. Nguyen and Byun used a nozzle that was not connected electrically to overcome the electrical breakdown in a conventional NFES system. As shown in Fig. 9.9, an AC voltage is applied to an extraction electrode and the reflection of charged droplets due to patterned geometry on the substrate decreases owing to the patterned geometry on the substrate. Under the AC voltage, positively and negatively charged droplets can be obtained. With the alternation of positive and negative voltage, the jet will be turned to an electrically neutral state, which is helpful for the continuous ejection of droplets even at the peak signal of voltage. Based on the single AC potential setup, dots with sizes ranging from 10 to 30 mm were generated on the substrate. Zheng et al. investigated the effects of process parameters on the microdroplet ejection behaviors under the AC electrical field. The deposition frequency increases and the droplet diameter decreases with increasing AC voltage frequency. In addition, the deposition frequency and droplet diameter increase with increasing duty cycle and solution supply rate. Based on the aforementioned research, Liu et al. printed a bead-on-string structure under an AC electric field. The positive voltage drags out more solution and form beads, while the negative pulse voltage provides the opposite force to stretch the jet into nanofibrous structures between two adjacent beads. The stability of the jet can be enhanced by increasing the voltage frequency. As the voltage frequency increases from 10 to 60 Hz, the diameter of the bead structure decreases from 200 to 110 mm, as presented in Fig. 9.10.

How To Fabricate ZnO Gas Sensor Using Near-Field Electrospray

In addition, a thin-film ZnO gas sensor was fabricated by using near-field electrospray, as shown in Fig. 9.8. Comb electrodes with a large contact area were printed to increase the sensitivity of micro/nanosensors. The electrospray micro/nanoparticles were deposited over the electrodes, which would be heated and oxidized to form a ZnO semiconductor at 500℃ afterward. The experimental results showed that the fabricated sensor displays high sensitivity because of the small diameter and high specific surface area of the electrospray particles, indicating a new promising method for the integration fabrication of micro/nanodevices.

Nanoscale Diameters

Nanofibers with nanoscale diameters are attractive for their wide applications, ranging from envi ronment to energy, electronics, and health care. As the diameters of electrospun fibers are usually larger than 100 nm, several approaches, such as jet stretch enhancement, coreeshell or multicom ponent spinning, and spinning of extremely diluted solutions, have been proposed to further decrease the fiber diameter. However, the limited thinning capacity (usually >50 nm) and low production still remain. Electronetting, as a polymer processing technology, achieves the large-scale fabrication of 2D nanonet materials with nanoscale diameters. The average diameter of the interlinked nanowires in nanonets is about 10e30 nm, which is about 1 order of magnitude smaller than that of conventional electrospun fibers. For example, the major distribution region of nanowires in PAA nanonets reported by Wang and coworkers is 10e20 nm, while for PA-6 nanonets, each nanowire has a uniform diameter of w26 nm, as shown in Fig. 8.6. Benefiting from the extremely small diameter, the resultant nanonet membranes usually show enhanced surface area compared with the common electrospun nanofiber membranes. According to the results of

Foshan Lepton Precision M&C Tech Co.,Ltd Qualification Honor

Foshan Lepton Precision M&C Tech Co.,Ltd Qualification Honor

Foshan Lepton Precision M&C Tech Co.,Ltd Development History

In 2004, electrospinning research team was founded;

In 2006, first proposed Near-Field electrospinning theory;

In 2014, Foshan Lepton Precision M&C Tech Co.,Ltd was founded as the platform in electrospinning industrialization;

In 2016, got the High-tech Enterprise Certificate;

In 2017, the company's chief technical adviser was awarded "intelligent manufacturing star" in Foshan high-tech industrial development zone;

In 2018, it was listed as a warehousing technology enterprise in Guangdong province.

Foshan Lepton Precision M&C Tech Co.,Ltd Company Profile

        Based in Foshan National HighTech Industries Development Zone, Foshan Lepton Precision M&C Tech Co.,Ltd (Qingzi Nano) is a national hightech enterprise which dedicate to the research and development of electrospinning and eletrospraying printing techniques.  We manufacture, sale and provide technical support for electrospinning and electrospraying machines, electrospun nanofiber production line, bioscaffold 3Dprinter and nanofiber products.

         With our powerful and innovative research and development team, Qingzi Nano has established close cooperation with Nanyang Technological University, Xiamen University, Tsinghua University, Sun Yatsen University, South China University of Technology, Guangdong University of Technology and Jinan University. Our techniques and products have been widely applied in the field of environment, energy, electronics, biomedical etc. Our electrospinning products have been awarded as innovative hightech products.

        Qingzi Nano owns more than 80 patents, including over 50 patents for inventions on the techniques and equipment of electrospinning, bio-3D printing and electrospray printing.

Ion-Initiated Splitting of Electrospun Fibers

In 2009, another possible formation mechanism of 2D nanonets was proposed by Kim and coworkers, and they claimed that nanonets could be produced by tailoring the polar polymer solutions based on the inspiration of ionic salts. During the electrospinning process, high voltage allows the polymer solution to be charged and the resultant charge repulsion causes the solution to be deformed, forming the Taylor cone and its ejected jets. They thought that the formation of nanonets was attributable to the ions in the polymeric solution, and should occur at the place of formation of the main nanofibers. The nanonets can be considered as joints between the main fibers, and among the nanowires from the nanofibers, and between the nanowires and the nanofibers, which can be confirmed by transmission electron microscopy results, as shown in Fig. 8.4B and C. Taking into account the solvent evaporation process and randomly distributed state of the ions, the highly viscous solution at the tip end would be compelled to form joints because of the ionic balance among the unsolidified nanofibers, resulting in new nanowires after complete solidification. To further clarify the

Intertwining of Branching Jets

Based on a study on the fabrication of nylon-6 nanofiber/nets from polyelectrolyte solution, Tsou and coworkers proposed a plausible formation mechanism of intertwining of branching jets. According to their viewpoint, in addition to the main whipping jet, many tiny subsidiary jets form simultaneously and undergo the whipping process as well during electrospinning, as exhibited in Fig. 8.3. Owing to the vigorous whipping at high speed, the subsidiary jets would be intertwined in the chaotic whipping region when they overcame the obstacle of the mutual repulsive interaction. With the rapid solvent evaporation, the resultant networks consisting of subsidiary branching jets could be solidified between the scaffold nanofibers, resulting in the formation of 2D nanonets with interlinked nanowires. Although branching jets with microsized diameters in the straight jet segment have been observed by using a high-speed camera, the formation process of subsidiary jets cannot be observed, owing to their extremely small diameters and vigorous whipping. Therefore, this proposed mechanism based on the intertwining of branching jets is just a possible explanation, since it has not taken into account that

Intermolecular Hydrogen Bonding

By investigating the formation process and structures of nylon-6 (PA-6) and methoxypolyethylene glycol (MPEG) oligomer/nylon-6 nanofiber/net membranes, Kim et al. attributed the formation of nanonets to the hydrogen bonds between the nanonets and the nylon-6 nanofibers, and proposed the relevant intermolecular hydrogen bonding mechanism. Fig. 8.2 presents a schematic illustration of the hydrogen bond formation mechanism. In the high-voltage electric field, the electronegativity difference between hydrogen and oxygen/nitrogen atoms would be further enhanced and result in the high polarity of the molecules due to the more charges provided by the electric field. The protonated amide groups of ionic molecules would form strong hydrogen bonds with oxygen atoms of the nylon-6 molecules in scaffold nanofibers, and oxygen atoms of the nylon-6 molecules could connect with hydrogen atoms of the amide groups of the nanofiber as well, to form the interconnected spiderweb-like nanofibers/nets. Moreover, the intermolecular hydrogen bonding between oxygen and hydrogen atoms of MPEG molecules and amide groups of nylon-6 molecules was also proposed to reveal the formation of MPEG oligomer/nylon-6

Basic Setup For Electronetting

As electronetting and electrospinning are similar electrohydrodynamics techniques and the former accompanies the traditional electrospinning process, the basic setup for electronetting is almost the same as the electrospinning setup. The typical basic setup for electronetting includes two standard apparatuses of vertical and horizontal forms, of which the horizontal one is widely used, as shown in Fig. 8.1A. It is clearly shown that the typical electronetting setup consists of four parts, a high-voltage power supply, syringe pump, spin neret, and collecting receiver. The power supply with high voltage applied to the needle is used to induce the formation of charged liquids in the form of jets and/or droplets. A direct current power supply is usually employed for electronetting, while an alternating current supply can also be used as the spinning power. The spinneret with designed needle is attached to the syringe pump, which can control the flow rate of the precursor solution. Generally, the collecting receiver, such as a metal plate, screen, or rotating roller, is used to collect the nanofiber/net assemblies by virtue of the electric field between the needle of the spinneret and the receiver.

CENTRIFUGAL FORCE

Using PEO as a model polymer, Peterson et al. produced nanofibers at a production rate of 6.5 mg/h cm2(Fig. 7.19). Important parameters that affect the nanofiber production rate include voltage, spinneret rotation speed, solution feed rate, distance between spinning head and collector, and solution concentration. In this way, polyacrylonitrile fibers were produced successfully. This technique is also compatible with various collectors, such as a moving belt for collecting large membranes, parallel collector electrodes for aligned fibers, and parallel collector electrodes with one rotating electrode for producing short yarns.

A SUMMARY OF NEEDLE-LESS ELECTROSPINNING SPINNERETS

Moreover, asymmetrical spinnerets, such as a coil (Fig. 7.18), could also produce uniform nano- fibers and nanofiber mats. Unlike the symmetrical spinnerets, the coil spinneret shows an uneven electric field distribution.

Disk

A slowly rotating disk, which is partially immersed in polymer solution, eliminates the need for self replenishment of the solution at the fiber-spinning edge (Fig. 7.15). It also ensures a fresh coating of solution on the disk surface and prevents the solution from solidifying at the disk edge during electrospinning. Rotating cylinder and disk spinnerets have been analyzed by Niu et al. The rim radius of a cylinder spinneret can reduce discrepancies in electric field intensity and influence the fiber productivity. Thinner disk spinnerets increase the electric field intensity, leading to finer nanofibers and higher throughput.

WIRE SPINNERETS

During the electrospinning process, the high voltage was applied to the stationary wires and a polymer solution was loaded on the surface of the wires by moving the wire through the polymer solution. Then, numerous jets were generated from the wire surface. It has a better spinning performance than the previous version, which use a rotating drum as spinneret.

CLEFT SPINNERET

Lukas et al. reported an electrospinning setup that used linear clefts as the spinneret (Fig. 7.6). The authors also developed a one-dimensional electrohydrodynamic theory to explain the process of electrospinning conductive liquids from an open plane surface (Fig. 7.6). During the electrospinning process, the amplitude of characteristic wavelength grew faster because of the electrical force. The fastest-growing stationary wave marked the onset of electrospinning from a free liquid surface. This theory not only predicated the critical value of the electrospinning process but also explained the upward needle-less electrospinning.

MAGNETIC FLUID

In 2004, Yarin and Zussman reported a needle-less electrospinning system that used a magnetic field to initiate the jet formation. The setup comprised a bottom layer of ferro magnetic fluid and an upper layer of polymer solution (Fig. 7.4A). When an external magnetic field was applied to the fluid system and an electric field was added simultaneously to the polymer solution layer, the ferromagnetic fluid triggered the formation of steady vertical spikes, which perturbed at the interlayer interface. Under the action of a strong electric field, these spikes were drawn into fine solution jets (Fig. 7.4B). Compared with multineedle electrospinning, this needle-less setup can produce polyethylene oxide (PEO) nanofibers with 12 times higher productivity. Nevertheless, the nanofibers electrospun are relatively coarser with larger diameter distribution.

Needle-less Electrospinning

Needle-less electrospinning appeared in the early 1970s, when Simm and coworkers filed a patent on using an annular electrode to electrostatically spin fibers for filtration appli cations. Next, Lukas et al. investigated the self-organization of charged jets initiated from the open free-liquid surface in the electrospinning process. Lin and colleagues developed a rotating spiral coil spinneret, which had a high fiber production rate with well-controlled fiber morphology. Liu et al. electrospun nanofibers by blowing air into the polymer solution. The bubbles generated assisted in jet initiation. Since 2008, growing research has been devoted to needle-less electrospinning. Research publications have been increasing constantly over the years. Over 100 articles about needle-less electrospinning or free-surface electrospinning have been published since 2007. The publication number between 2014 and 2016 was approximately 10 times more than that of 2007e2013 (Fig. 7.2A). Research is widespread in many countries. China, Australia, and the Czech Republic take about 80% of publications, followed by the United States, Germany, and England (Fig. 7.2B).

Multineedle Electrospinning Apparatus

Nanofiber yarn is defined as a twisted nanofiber bundle or tow featuring a morphology that is similar to filament yarn or spun yarn. Nanofiber yarn is mechanically suitable for weaving, knitting, and other methods used to produce fabrics. He and colleagues succeeded in producing continuous and twisted polyacrylonitrile nanofiber yarns by using a four-nozzle bubble electrospinning method, and the twist of the prepared nanofiber yarn could be adjusted by controlling the rotational speed of the collecting device, as shown in Fig. 6.13A and C. Two pairs of nozzles were positively and negatively charged, and the metal funnel collector was not grounded. After voltage was applied, the conjugate electric field came into being between the positive and the negative nozzles; however, the metal funnel located in the middle of the two groups of nozzles would have charges that were opposite those of the nearby charged nozzles. Therefore, induction fields were created between both edges of the funnel and their nearby charged nozzles. The electronic field lines were mainly distributed between the positive and the negative nozzles, and between the nozzles and the edge of the funnel. Because of the

Efficient Needle-free Electropinning Nanofiber Production Line MF01-003 ...

Qingzi Nano’s MF01 is an equipment of series of nanofiber production line, including needle spinning( MF01-001 and MF01-002) and needle-free spinning (MF01-003 and MF01-004) series. It is based on electrospinning technology to produce nanofiber membrane in high efficiency and quantity production, which can meet the growing need for nanofiber applications and achieve industrial benefits.

Features:

1. Quickly manufacture sample;
2. Automatic roll-to roll system;
3. Temperature and humidity controllable fabrication;
4. Nanofiber membrane drying system;
5. Safeguard system;

 Parameters:

1. Number of spinning electrode: 2;
2. Spinning electrode width: 600mm;
3. Effective width of nanofiber layer: 250-600mm;
4. Speed of roll-to-roll: 0-5m/min;
5. Feeding system: corrosion resistance, high-voltage resistance;
6. Power supply: 220V 50Hz.

Near Field Direct Writing Electrospinning Equipment M08 Spinning Process

Features: 

1. -Printing resolation less than 50nm;
2. -Nanofiber highly oriented and controllable;
3. - International R & D team pioneering technology;
4. - Exclusive patented technology;
5. -Micro nano manufacture excellent tools

Near Electrospinning Technology Classification

Solution Near-field Electrospinning

Solution near-field electrospinning process, the printing material is prepared into a solution, and using electrostatic field print orientation nanofibers. It can produce a fiber orientation controllable fiber diameter range is 50nm-20μm, the solution electrospun near-field have more suitable materials.

Melt near-field electrospinning

Melt Near-field electrospinning process, the printed material is heated and melted, assisted with the electrostatic field, fibers with a diameter range of 500nm-50μm can be prepared, high 3D printing capability, very suitable for producing three-dimensional biological tissue engineering scaffolds.

Near field electrospinning equipment parameters

1. High voltage power supply: 0-30kv, adjustable;
2. Solution spinning nozzle: solution supply volume at least 10μl/h;
3. Melt spinning nozzle: nozzle temperature: 0-300℃, adjustable, precision pneumatic extrusion;
4. Printing environment temperature: indoor temperature -50℃, adjustable;
5. Collection platform: printing range 150*150mm, platform speed: 0-200mm/s, resolution: 50nm;
6. Nozzle height: 0-80mm, adjustable, resolution: 50nm;
7. Printable materials: PE0, PVA, PLA, PCL, PLGA, chitosan, sodium alginate, collagen, hydroxyapatite, PVDF and other hundreds of organic or inorganic materials;
8. printable user-defined patterns;
9. printable 3D structure;
10. customizable : temperature controllable collector;
11. customizable : multi-nozzle device.

Single-bubble Electrospinning Unit

The structural diagram of a single-bubble electrospinning unit is shown in Fig. 6.7. Bubbles are formed on the mouth of the nozzle during the experimental process, and the forces on the charged bubbles are the electric field force (Fe), the force caused by the difference in air pressure inside and outside of the bubbles (Fp), and the surface tension of the bubbles (Ft) after voltage application. The bubble film composed of the spinning solution is drawn and then ruptured into multijets when the electric field force exceeds Fp and Ft. Finally, the multijets are stretched into nanofibers via the electric force. Bubbles can be continually formed on the mouth of the nozzle, and each bubble bursts to form high-speed multiple jets. The squirting speed of the air is controlled to increase nanofiber yield. The nanofiber yield is as high as 2.352 g/h, which is far greater than the yield achieved by conventional single-needle production.

Multi-needle Nanofiber Electrospinning Production Line MF01-001 Spinning...

Qingzi Nano’s MF01 is an equipment of series of nanofiber production line, including needle spinning( MF01-001 and MF01-002) and needle-free spinning (MF01-003 and MF01-004) series. It is based on electrospinning technology to produce nanofiber membrane in high efficiency and quantity production, which can meet the growing need for nanofiber applications and achieve industrial benefits.

Features:

1. Automatic roll-to roll system;
2. Precious feeding system;
3. Multi-needle electrospinning systems;
4. Temperature and humidity controllable;
5. Nanofiber membrane drying system;
6. Safeguard system;

Parameters:

1. Needle Qty: 256, or more( customizable);
2. Roller speed:0-20m/min, adjustable;
3. Feeding system: corrosion resistance, high-voltage resistance;
4. Continuous operation time:≥8 hours;
5. Power supply: 380V;
6. Effective width of nanofiber layer: 660mm, or other( customizable).

Maghemite (γ-Fe2O3) Fiber-in-tube And Tube-in-tube Nanostructures

Inspired by the nanowire-in-microtube structure, Jian-guo Guan and colleagues proposed a facile and effective nonequilibrium heat-treatment approach combined with electrospinning for fabrication of maghemite (γ-Fe2O3) fiber-in-tube and tube-in-tube nanostructures. The pre cursor was composed of PVP and iron citrate. Fig. 5.21 shows SEM images and corresponding TEM images of as-obtained γ-Fe2O3 fiber-in-tube and tube-in-tube fibers. The figure reveals that the tips of the inner structures are totally separated from the outer tube, and the inner and outer tubes have a closed end. The resultant γ-Fe2O3 fiber-in-tube and tube-in-tube nanostructures may have important applications in a number of fields, such as magnetic separable catalysts or catalyst-supporting mate rials, sensors, absorbents, microreactors, and so forth, because of their structural characteristics and good magnetic properties. This method can intentionally control the contraction direction of the precursor nanofibers during the heat-treatment process by adjusting only heating rate (R) of the calcination, as R can be easily utilized to tune the temperature gradient established in

Coaxial Cojetting Electrospinning Method

Because they have heterogeneous components and anisotropic properties, Janus fibers have wide applications in many fields. As a typical technique, side-by-side electrospinning has been proven to be a facile and cost effective method for preparing Janus fibers. But this method can be used only for fabricating dual-paratactic fibers. Based on this, Joerg Lahann et al. reported a coaxial cojetting electrospinning method with dual core flows and triple core flows. Using this method followed by crosslinking, microsectioning, and shell removal, Janus microcylinders and triple paratactic microcylinders composed of different polymers were prepared (Fig. 5.19A). Fig. 5.19B shows the cross-sectional CLSM images of triple coreeshell fibers. Blue, green, and red channels represent poly(vinyl cinnamate)(PVCi), PEO, and PMMA, respectively. Uniquely shaped building blocks can be fabricated by photopatterning of one hemisphere of the microcylinders. This approach can result in Janus coreeshell fibers and triple coreeshell fibers, where the core is defined by the parallel center jets. In all experiments, a PLGA solution was used as the shell stream, which governs the jetting performance and acts as a

Side-by-side Electrospinning Method

In 2015, White and Yu’s group further studied and developed the side-by-side electrospinning method by regulating the angle between the two needles of the spinneret. By varying the angle, the width, interfacial area, and volume of each side would also be changed. Therefore, different Janus nanofibers with adjustable structures were obtained. The diagram of the spinneret is shown in Fig. 5.17A, and the angle marked q could be tuned to change the morphology of the fibers. The solutions in this work were mainly PVP K-60/rhodamine B and Eudragit@L100/8-anilino-1-naphthalenesulfonic acid ammonium salt in a mixture of ethanol and DMAc. For the side-by-side electrospinning, the two solutions were stretched from their own needles with the same electrostatic charge and came together at the outlet of the nozzle. With their mutual electrostatic repulsion, the two solutions may separate from each other, which would lead to a failure to form the side-by-side structure. In this research, however, arranging the angle between the two ports to some suitable value would contribute to the fabrication of the side-by-side structure. The corresponding TEM images for when the values of the angle q were 40, 50,

CENTRIFUGAL ELECTROSPINNING MACHINE

More spinnable material;

High voltage power supply: 0-30kv;

Centrifugal speed: 0-7000rpm;

Temperature and humidity controllable;

Optional collector: disc, vertical grid;

Precious feeding pump: supplying liquid continuously.

Electrospun Bifunctional Janus Nanobelts

In 2014, electrospun bifunctional Janus nanobelts were fabricated by Dong and coworkers (Ma et al., 2014). The setup is shown in Fig. 5.16A. Nanobelts are characterized by anisotropy, large width/ thickness ratio, and unique optical, electrical, and magnetic properties that are different from those of nanofibers. The side-by-side nanofibers these authors made included Fe3O4/PMMA as one side, while the component of the other side was Tb(BA)3phen/PMMA. The SEM image of the nanobelts obtained by side-by-side electrospinning is shown in Fig. 5.16BeD shows the EDS line scan analysis of the nanobelts, which confirmed the morphology of side by side. Compared with the Fe3O4/Tb(BA)3phen/ PMMA composite nanobelts, the biphasic Janus nanobelts possessed both high fluorescence intensity and saturation magnetization.

QZP 1 Portable Electrospinning Apparatus

QZP - 1 portable electrospinning apparatus is researched,  developed and produced by Foshan Lepton Precision M&C Tech Co.,Ltd., , dedicated to the laboratory of portable handheld device, its size is equivalent to mobile phones, small and light, easy to carry, can be used in the early stage of the electrospinning experiment, classroom demo or innovative experiments, can also be applied to wound dressing preparation, in a timely manner to protect the wound.

Electrospinning Nanofibers Having a Core-sheath Structure

Li and Xia fabricated hollow fifibers made of titania by coaxial electrospinning through a two capillary coaxial spinneret and subsequent extraction of mineral oil as well as calcination of the core, in 2004. This group solved the instability problem by coelectrospinning two immiscible solutions, followed by gelation (or crosslinking) and stabilization of the sheath. In this work, an ethanol solution containing a solegel precursor, an acid catalyst, and a polymer was loaded into the sheath capillary, while heavy mineral oil was loaded into the core capillary. When the correct viscosities and rates of hydrolysis were achieved as stable bicomponents, a Taylor cone was formed, resulting in a stable coaxial jet. One of the major obstacles involved in the formation of core-sheath or hollow nanofifibers is the instability of the core. With the addition of a solegel precursor, gelation in the outer surface of the sheath during the spinning process prevented structural breakdown and resulted in fifibers with a stable morphology. Hollow fifibers could be obtained by extracting the mineral oil core with a solvent such as octane. As shown in Fig. 5.8A, the setup for

Lab Scale Electrospinning Machine E03-001 Sold to The University of Waterloo In Canada

On June 24, Lab Scale Electrospinning Machine E03-001 was delivered to The University of Waterloo In Canada. This equipment is selling well, the price is less than ten thousand dollars, welcome your inquiry.

Features:
Desktop style,  small size;
Function integrated, professional;
Superior performance, CE/FCC certification;
4.3 inch numerical screen, simple and clean integration operating system;
Highly cost effective, elegant appearance;
Tool machine, affordable;

Parameters:
Spinning voltage: 0-30kv;
Both roller and panel collector;
Nozzle reciprocating motion breadth: 150mm
Dimension: 600*600*800mm
Net weight: 47.46KG

Centrifugal Electrospinning Machine

Features:

1. More spinnable material;
2. High voltage power supply: 0-30kv;
3. Centrifugal speed: 0-7000rpm;
4. Temperature and humidity controllable;
5. Optional collector: disc, vertical grid;
6. Precious feeding pump: supplying liquid continuously.

Nanomaterial Spraying Machine

Introduction

Nanomaterial spraying technology is based on electrostatic, ultrasonic, gas field for fine spraying of low-viscosity materials, solving the agglomeration problem in the use of nanoparticles. With nano-scale microsphere spraying, the technology can be applied to the preparation of fuel cell proton exchange membranes, electrode catalytic materials, battery separators, heat exchange membranes, quantum materials, etc.

Features

1. Feeding method: injection pump;
2. Applicable solution viscosity: ≤30cps;
3. Environment temperature range: room temp up to 60±3℃ adjustable;
4. Environment humidity range: room humidity down to 40％±5％RH adjustable;
5. Independent R&D.

PROFESSIONAL MICRO/NANO 3D PRINTER

Features

1. Desktop style, small size;
2. Maximum printing speed: 300mm/s;
3. High voltage power supply: 0-10KV adjustable;
4. Optional: melt nozzle; precision injection pump;
5. Opening mechanical structure, easy to self-assembled and disassembled, can be applied in maker education;
6. Optional dual Y-axis motion system for printing continuously.

Morphology of Molecular Assembly

Amphiphilic peptides have a hydrophilic head group and a hydrophobic alkyl tail. The hydrophobic tail helps in aligning the head group to form various secondary, supersecondary, and tertiary conformations. Very thin cylindrical nanofibers (<10-nm diameter) with high aspect ratio, or nano belts, are achieved by a self-assembly of peptide amphiphiles (PAs) under specific solution conditions (pH, ionic strength, and temperature). The 1D nanostructures can interact further among one another, making a 3D network. These 3D network structures make a hydrogel in water. Hydrophobic and electrostatic interactions are the dominating forces in the self-assembly of amphiphilic peptides. The amphiphilic cyclic peptide composed of two b-glucosamino acids and one trans-2-aminocyclohexylcarboxylic acid in formic acid and water (7/3 v/v) makes self-assembled rods and fibers of different dimensions depending upon the solution concentration. A concentration of 1.1 10 5 M provided a rod-shaped assembly of c. 5-nm diameter, which corresponds to a nine-columnar (3 triple bundle) structure (Fig. 4.7A). By increasing the peptide concentration to 1.1 10 4 M, a uniform fibrous assembly of c. 15 nm in

Nano-microfiber Composites For Filtration

Nanofibers prepared by molecular self-assembly are in general not self-supporting and therefore require stabilizing scaffold structures. In fact, a lot of research in the past has been done with su pramolecular self-assembly of molecules forming a network of nanofibers used as organo/hydro gelators. But efforts to use them as a self-standing membrane or as free fibers were not strong. Therefore, the self-assembly of trisamides was also tried on a substrate, i.e., other microfiber non wovens, leading to microenanofiber composites (Fig. 4.4) used for filtration (Weiss et al., 2016).

Polymer/Carbon Nanotube Composite Nanofibers

To improve the compatibility between CNTs and polymers, the surface functionalization of CNTs has been developed (Kharaziha et al., 2014; Molnar et al., 2008; Ra et al., 2005; Mazinani et al., 2009; Yee et al., 2012; Subagia et al., 2014; Diouri et al., 2014). For instance, Kharaziha et al. established a simple strategy to prepare electrospun gelatin/CNT composite nanofibers by using carboxyl acid groupemodified CNTs, and the well-dispersed CNTs aligned along the fibrous axis could be observed (Fig. 3.15B). This work demonstrated CNTs as a component of tough and flexible scaffolds with outstanding electrical properties (Kharaziha et al., 2014). Molnar et al. (2008) synthesized PVA/CNT composite nanofibers with diverse types of CNTs and different functional groups via electrospinning. Furthermore, other synthetic methods such as electrospinning combined with electrospraying and a surface adsorption approach have been developed as well (Xuyen et al., 2009; Kim et al., 2006b; Vaisman et al., 2007; Dai et al., 2011; Rana and Cho, 2011).