Rotating drum collector. The first commercial steps in nanotechnology were taken in the textile field. At the molecular level, it is currently possible to improve textiles, provide innovations, increase resistance and functional properties. More work in the field of nanotechnology will add value to the product and bring more income to the textile industry.
Electrospinning rotating drum collector
The table below summarizes the typical processes that have been developed for the fabrication of polymer-based nanofibers. Although the term nano has attracted much attention in fiber studies, the commercial potential of nanofibers is still unclear. Much discussed potential markets are filtration, protective clothing and polishing cloths. With the expansion and improvement of nanofiber production techniques, the production cost will decrease, and the development of related markets will become very interesting.
Rotating drum collector
In order to provide the desired properties such as diameter, morphology, position, distribution of the fibers produced in the electrospinning process, only the process parameters should be well known. However, process control is difficult because many parameters affect the process. The parameters affecting the electrospinning process can be considered in three main sections (Table 3.7). These are solution parameters, process parameters and environmental parameters.
Rotating drum collector electrospinning
The properties of the polymer solution are the most important parameters affecting the electrospinning process and the properties of the fibers formed. The parameters of the solution are the molecular weight of the polymer, the surface tension, the electrical conductivity and the dielectric properties of the polymer solution.
Rotating drum collector fisher
One of the factors affecting solution viscosity is the molecular weight of the polymer. In general, when samples of different molecular weights of the same polymer are dissolved, the solution obtained from the high molecular weight polymer has a higher viscosity than the low molecular weight solution. In other words, as the molecular weight of the polymer increases, the viscosity of the solution also increases.
Rotating drum collector nanofiber
Similar to the increase in molecular weight, the increase in concentration also increases the complexity of the polymer chain and thus the beam in the electrospinning process.
Spraybase rotating drum collector
To ensure its continuity. With increasing concentration, the formation of spheres in the obtained nanofibers decreases, while the shape of the spheres changes from spherical to flat (Figure 3.20) (Kozanoğlu, 2006). However, minimum polymer chain complexity and therefore minimum viscosity is required for electrospinning. Too high a viscosity makes it difficult to pump the solution through the nozzle. Also, too high a viscosity can cause the solution to dry at the tip of the nozzle before electrospinning begins.
At low viscosity, chain complexity is low and the effect of surface tension forces on the nozzle during electrospinning is dominant. Balling can therefore be observed due to the lack of a continuous jet. An increase in viscosity increases the complexity of the polymer chain and ensures continuous jet formation in the electrospinning process (Üstündağ and Karaca, 2009). With increasing viscosity, the fiber diameter also increases. This is likely due to the solution’s increased resistance to the drag caused by the jet loads.
In order to initiate electrospinning, the electrically charged solution must overcome surface tension. Surface tension has the effect of reducing the surface area per unit mass of liquid. When the concentration of free solvent molecules is high due to surface tension, the tendency of the solvent molecules to aggregate and become spherical increases. In this case, as the polymer jet moves toward the collector plate, surface tension can cause beads to form along the jet.
High viscosity means more interaction between the solvent molecules and the polymer. So when the solution is stretched under the influence of stresses, the solvent molecules tend to diffuse into the complex polymer molecules, so the solvent molecules tend to stick together under the influence is reduced surface tension