Nanofiber Mask Material Production Equipment

In 2020, the mask officially became the most important strategic material for the national economy. As the core filter layer of the mask, "melt-blown cloth" mainly has the following problems:

1. Large gap, short supply.

2. As of February 29, melt-blown fabric prices were $57,468 / ton (continuing upward trend...).

3. Delivery date: delivery cannot be made on time or has been delayed.

4. The quality is low, and the fake and inferior melt-blown fabric emerges one after another in the market.

How to do?

It is urgent to find alternative products!

Nanofiber membranes can replace melt-blown cloth as a filter material for masks and solve the problem of repeated use of masks, chinanews.com reported recently. Premier Li Keqiang has asked the Drug Regulatory Authorities to speed up the review and, once approved, increase mass production. Li stressed that masks are now "weapons" for medical workers and "shields" for ordinary people.

The nanofiber filter membrane referred to by Premier Li has become an important substitute for melt-blown cloth.

How to choose the filter material equipment?

As nanofibers industrialization leading enterprises, Qingzi Nano early in 2004 began to set up the team, has been developed and selling series of industrialization of nanofiber production line, have a reliable production technology solutions, but for the material of this outbreak instead of melt-blown fabric production provide a full range of production equipment and production instruction, can rapid delivery, let you mass production immediately, and solve the problem of melt-blown material shortage.

Enterprise Background
As early as 2004, the technical team of Foshan Lepton Precision M&C Tech Co., Ltd. (hereinafter referred to as Qingzi Nano) was established. The company is located in Foshan national high-tech industrial development zone, focusing on the research and development of electrospinning nano-fiber technology and equipment. In view of the epidemic situation, our company cooperated with The State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment of Guangdong University of Technology, The Numerical Control Equipment Collaborative Innovation Research Institute of Nanhai District Guangdong University of Technology, and the Jihua Laboratory to develop the production equipment scheme of the nano-fiber filtration membrane.

Qingzi Nano nanofiber mask filter material equipment is now online, welcome to consult and purchase! First purchase, early production, quick return. We have a tight schedule, please buy as soon as possible.

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Best wishes to you, 

Yours sincerely,

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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.