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CHAPTER 1
CONTROLLING THE STABILITY OF FLUID JET IN THE ELECTROSPINNING OF FIBERS: MATHEMATICAL MODELING
S. PORESKANDAR, SH. MAGHSOODLOU, and A. K. HAGHI*
University of Guilan, Rasht, Iran
CONTENTS
Abstract
1.1 Introduction
1.2 Experimental
1.3 Results and Discussions
1.4 Conclusion
Keywords
References
ABSTRACT
The most vital challenge in the electrospinning process is to achieve uniform nanofibers consistently. In addition, the jet shows some unstable behavior during the process. A better understanding of electrospinning jet movement can be obtained by using modeling and simulation. The main purpose of this chapter is simulating the unstable behavior of the jet and investigating the effects of the most significant parameters (i.e., solution concentration, spinning distance, applied voltage, and flow rate) on the pathway of electrospun polyvinyl alcohol nanofiber jet using a mathematical model. It is observed that, at a constant concentration, increasing applied voltage in the long spinning distance made a shorter pathway of nanofiber jet. Also, the longest pathways were created by decreasing spinning distance and increasing charge accumulation that made the longest pathway.
1.1 INTRODUCTION
Nanotechnology is a unique technology that will make most products more effective and less expensive. Research and development in this field guides toward understanding and producing materials with innovative properties.1 Additionally, the growth in the number of publications and patents in this field has become important in the recent years.2 Electrospinning, as a significant branch of nanotechnology, must be proved as a cheap and straightforward method to create nanofibers.3, 4, 5, 6 These materials appear in a broad range of potential purposes (i.e., filters, tissue engineering scaffolds, and protective clothing).7, 8, 9, 10 Creating electrospun nanofibers is a process based upon a simple concept that produces nanofibers through an electrically charged polymer solution, explained schematically in Figure 1.1.11 Thus, this process can be separated into four sections, as shown in Figure 1.2.
The vital challenge in this process is to perform uniform nanofibers consistently.12,13 On the other hand, the physical characteristics of electrospun nanofibers, such as fiber diameter, depend on numerous parameters which are mainly divided into three categories: solution conditions (i.e., solution concentration), processing conditions (i.e., applied voltage, flow rate, and spinning distance), and ambient conditions (i.e., temperature and humidity).14, 15 Also, controlling the property of the nanofibers is essential for producing well nanofibers.16 As a concept, successful electrospinning requires an understanding of the complex interaction of electrostatic fields, properties of polymer solutions, and component design and system geometry.17 In summation, this process deserves special attention and is necessary for predictive tools to better understand the optimization and controlling process.18 During this process, the jet shows some unstable behavior. Investigating the dynamical behavior of the jet is important for controlling and developing the process. For these reasons, modeling and simulation of electrospinning jet will provide a better understanding of the process.19,20 In this case, the mathematical models as displayed in Figure 1.3 were utilized.
FIGURE 1.1 Part one of standard electrospinning setup: (1) high voltage, (2) polymer, (3) syringe, (4) needle, (5) straight jet, (6) whipping instability, (7) collector.
FIGURE 1.2 ...
