The present invention relates to a hybrid electrospinning system for use in the fabrication of nanofibers with a broad range of application in many industries such as energy, agriculture, textile, food, security, sensor applications, filtration applications and biomedical applications, capable of upgrading the nanofiber production capacity by up to hundred times and also guaranteeing constant nanofiber diameter and surface characteristics throughout the whole production process.

STATE OF ART

The so-called electrospinning method, which is based on the fabrication of nanofibers by means of electric field forces, is known as an“electro-hydrodynamic process” since early 1900s. Advancements in the field of nanotechnology particularly since 2000 have correspondingly driven an increase in research and development efforts, resulting in the emergence of dozens of publications and patents in the field almost every day. Some of the exemplary publications and patents relating to such efforts are listed below:

B Satilmis, T Uyar, Electrospinning of Ultrafine Poly (1 -trimethylsilyl-1 - propyne) [PTMSP] Fibers: Highly Porous Fibrous Membranes for VOC Removal, ACS Applied Polymer Materials, 2019.

Z Li, Y Meng, C Wang, Y Cui, Z Yao, B Shin, G Liu, Enhancement-mode field-effect transistors based on Ti-doped In 2 O 3 nanowires fabricated by electrospinning, Journal of Physics D, 2019.

- US2019/062958A1 , Insulated nanofiber yarns

US2019/0608A, Nanofiber electrocatalyst

US10,207,490B2, Ultrafine fiber printing system In the electrospinning process, a polymer solution or melt suitable for fiber formation is exposed to an electric field force generated by a high-voltage power source, and a droplet is formed from this solution or melt first, shortly before it is transformed into a conical shape called the“Taylor Cone". Immediately thereafter, polymer envelope of the known art generally tears from the apex of the cone, and after advancing for a few centimetres as a flat jet, polymer molecules taper into an elongated spiral form under the influence of many forces such as evaporation of the solvent, electrostatic field forces and gravitational force before they reach the collector. Throughout the process from the feed inlet up to the collector, the polymer solution elongates thousands of times and transforms into nanofibers with nano sized particles.

Many factors such as the polymer type, solution or melt form, solvent type, polymer’s molecular weight and molecular weight distribution, conductivity of the solution, polymer feeder’s structure, distance between the feed inlet and the collector, collector’s configuration, ambient temperature, ambient humidity, ambient gas etc. effect the properties of nanofibers produced by the electrospinning process.

As is known, in the needle electrospinning process, only one jet is formed at the tip of the syringe needle, therefore, the capacity of the polymer solution to transform into nanofibers per unit time is very low. On the other hand, it is possible to form a plurality of polymer jets by means of electric field forces from a free polymer surface, such as the vessel surface, cylinder surface or wire surface, thereby improving the capacity of the polymer solution to transform into nanofibers per unit time. However, continuous evaporation of the solvent from free surfaces that allows the production of a plurality of jets constantly leads, as an undesired disadvantage, to a variation in the diameter and surface properties of the nanofibers.

Many studies have been carried out on nanofiber production, and in the national patent application no 2015/09091 , a study on“a multi-chamber feed hopper for obtaining composite nanofibers using centrifugal force” is disclosed. Said disclosure relates to a multi-chamber feed hopper system for obtaining composite or blended nanofibers using centrifugal force, which are useful in the fields of biochemistry, biomedicine, environment, medicine, electricity, food, packaging, filtration, energy, tissue engineering, drug release, composites, etc, wherein said system is composed of a feed hopper that is filled with polymer solutions and various fluids to obtain blended nanofibers, four pinholes positioned on the cylindrical surface of the feed hopper, a cover attached to the top of the feed hopper, a lower housing cover fixed to the bottom of the feed hopper, a clamp fixed to the lower housing cover, an external feeder into which additional polymer solutions and fluids are fed for subsequent delivery to the feed hopper, and a delivery conduit for the transfer of polymer solutions and fluids from the external feeder to the feed hopper. In another national patent application no. 2015/00254, a product defined as a “centrifugal spinning device used in the fabrication of nanofibers/microfibers” is disclosed. Disclosed therein is a centrifugal spinning device, which is suitable for industrial production by being connected to high flow-rate polymer solution tanks or an extruder used for nonwoven nano/microfiber production, and which essentially comprises at least one rotary cylindrical spinneret through which the polymer material is injected for fabrication of nonwoven articles, at least two bearings located on both ends of the spinneret which enable it to be fixed on the system and rotate around a specific orbit, at least one motor connection member located on at least one end of the spinneret which provides the connection to the power supply that enables the rotational movement, at least one spinning die located inside the spinneret which enables the polymer materials to be homogeneously distributed within the spinneret by means of its sectional area that is in the form of a half die.

European Patent application no EP2617879B1 discloses a system called “Combined spinning nozzle for manufacture of nanofibrous and microfibrous materials” wherein said nozzle comprises a thin-walled electrode and a first non- conductive body adjoining the first wall of said thin-walled electrode, said first body having its wall, which faces said thin-walled electrode, provided with an array of grooves formed therein and leading to the distal end of the combined spinning nozzle, and said grooves having their proximal ends connected to a supply of spinning mixture. Another European Patent application no EP1975284B1 discloses a configuration called“Electric spinning apparatus for mass-production of nano-fibers”, wherein said configuration relates to an electric spinning apparatus for mass-production of nano-fibers, more specifically, an electric spinning apparatus with electrical stability and improved nozzle blocks.

As a result, the need to eliminate the shortcomings and disadvantages of current configurations and applications of the present art has made it necessary to carry out an improvement in the relevant technical field. DESCRIPTION OF THE INVENTION

The present invention relates to a hybrid electrospinning system developed for use in the fabrication of nanofibers in an aim to eliminate the aforementioned disadvantages and introduce new advantages in the relevant technical field.

The present invention relates to a hybrid electrospinning system for use in the fabrication of nanofibers with a broad range of application in many industries such as energy, agriculture, textile, food, security, sensor applications, filtration applications and biomedical applications, capable of upgrading the nanofiber production capacity by up to hundred times and also guaranteeing constant nanofiber diameter and surface characteristics throughout the whole production process.

The object of the invention is to provide a hybrid configuration in which the advantages of the needle electrospinning system and the free-surface electrospinning system, which are both used in the present art for nanofiber production, are combined. Another object of the invention is to ensure increased number of jets ejected from the polymer solution while preventing the evaporation of the surface solvent by providing a hybrid configuration in which the advantages of the needle electrospinning system and the free-surface electrospinning system, which are both used in the present art for nanofiber production, are combined.

Another object of the invention is to upgrade the capacity of the polymer solution to transform into nanofibers per unit time by up to hundred times and also guarantee constant nanofiber diameter and surface characteristics throughout the whole production process thanks to increased number of jets ejected from the polymer solution and prevented evaporation of the surface solvent.

The structural and characteristic properties of the invention will now be described in further detail with reference to the illustrations below, therefore, assessment should be based on these illustrations and the detailed description.

Drawings

Embodiments of the present invention briefly summarized above and discussed in greater detail below, can be understood by reference to the exemplary embodiments described in the accompanying drawings. It should be noted, however, that the accompanying drawings only illustrate typical embodiments of the present invention, and that the invention therefore does not limit its scope since it may permit other equally effective applications.

In order to facilitate understanding, identical reference numbers are used where possible, to identify identical elements that are common in the figures. The figures are not scaled and can be simplified for clarity. It is contemplated that the components and aspects of an embodiment may usefully be incorporated into other embodiments without further explanation.

Figure-1 : Representative view of the system of the invention. Figure-2: The representative view of the hybrid electrospinning head contained in the system of the present invention.

REFERENCE NUMBERS

1. Polymer solution/melt

2. Fligh-voltage power supply

3. Polymer feed pump

4. Polymer delivery hose

5. Hybrid electrospinning head

7. Polymer jet

9. Electric field force

10. Collector

11. Motor

12. Earthing connection

13. Spacer

14. Electric field regulator

DETAILED DESCRIPTION OF THE INVENTION

Preferred alternatives, provided in this detailed description, of the hybrid electrospinning system of the present invention for use in the fabrication of nanofibers by means of electric field forces (9) are described so as to provide a better understanding of the subject without any limiting effect.

The invention relates to a hybrid electrospinning system for use in the fabrication of nanofibers with a broad range of application in many industries such as energy, agriculture, textile, food, environment, composite materials, security, sensor applications, filtration applications, biomedicine and biomedical applications, capable of upgrading the nanofiber production capacity by up to hundred times and also guaranteeing constant nanofiber diameter and surface characteristics throughout the whole production process. The system of the present invention generally comprises; at least one polymer solution / melt (1 ) to be used in the fabrication of nanofiber and in the formation of the raw material of the nanofiber to be produced; at least one hybrid electrospinning head (5) for preventing solvent evaporation while ensuring the launch of a plurality of polymer jets (7) from the whole surface; at least one high-voltage power supply (2) to provide polymer launch (jet formation) by overcoming the surface tension of the polymer solution/melt (1 ) from the hybrid electrospinning head (5); at least one polymer feed pump (3) for continuously feeding polymer to the hybrid electrospinning head (5) at a constant flow rate; at least one polymer delivery hose (4) to provide polymer flow between the polymer feed pump (3) and the hybrid electrospinning head (5); at least one electric field regulator (14) for regulating the lines of the electric field force (9) undertaking the polymer launch and thereby increasing the nanofiber production capacity; at least one collector (10) for collecting nanofibers from the polymer jets (7); at least one motor (11 ) to provide rotation of the collector (10); at least one earthing connection (12) to provide earthing of the collector (10) in order to create an electric field force (9) towards the collector (10); and at least one spacer (13) for adjusting the distance between the hybrid electrospinning head (5) and the collector (10) based on the characteristics of the polymer solution/melt (1 ) and intended nanofiber characteristics.

A polymer being suitable for fiber formation thanks to long chain molecules is made into a polymer solution/melt (1 ) by means of a solvent or heat. The polymer solution/melt (1 ) prepared is placed in a polymer feed pump (3) and conveyed to the hybrid electrospinning head (5) by means of the polymer delivery hose (4). The delivery of the polymer solution/melt (1 ) to the hybrid electrospinning head (5) is smooth and continuous throughout the whole process, and supply is provided by means of electric field forces (9) only to the extent of the nanofiber output.

While excessive level of feed may cause the polymer solution/melt (1 ) to overflow, a low level may lead to insufficient nanofiber production. An electric field force (9) is created between the positive pole of the high voltage power supply (2) applied to the hybrid electrospinning head (5) and the collector (10) earthed by means of the earthing connection (12). The intensity of the electric field force (9) and the lines of the electric field forces (9) are regulated by the electric field regulator (14) positioned around the hybrid electrospinning head (5). Hundreds of polymer jets (7) formed within the basin at the hybrid electrospinning head (5) by means of the electric field forces (9) first travel straight in a short distance, meanwhile the polymer solution/melt (1 ) tapers with the evaporation of the solvent and the polymer jet (7) moves along a helical orbit with a gradually increasing diameter under the equilibrium established between factors such as constantly changing electric field forces (9), gravitational force, surface tension forces of the polymer, frictional forces between the polymer jet (7) and air before it reaches the collector (10) in nanofiber form. The distance between the hybrid electrospinning head (5) and collector (10) is adjusted by means of the spacer (13).

Compared to traditional electrospinning processes, the hybrid electrospinning system ensures that polymer jets (7) can be produced in greater amounts by up to hundred times and a significant increase can be achieved in the amount of nanofiber produced per unit time.