Electrospinning instabilities

The electrospinning of poly(s-caprolactone) (PCL) solutions have been reported by Reneker et al. [74]. They varied the PCL solution concentrations between 14 and 18 wt%. The instability in the electrospinning of PCL results in the contact and merging of segments in different loops of the electrospinning jet to form garlandlike fibrous structures [74]. Yoshimoto et al. [75] have studied the potential of electrospun PCL fiber mats for use in bone tissue engineering. They found that the... 

Reneker, D.H., Yarin, A.L., Fong, H., and Koombhongse, S., 2000. Bending instability of electrically charged liquid jets of polymer solutions in electrospinning, J. Appl. Phys., 9(87), pp. 4531-4547. 

Figure 4.2 Schematic illustration of the conventional set-up for electrospinning. The insets show a drawing of the electrified Taylor cone, bending instability, and a typical SEM Image of the nonwoven mat of PET nanofibers deposited on the collector. The bending Instability Is a transversal vibration of the electrospinning jet. It is enhanced by electrostatic repulsion and suppressed by surface tension...

Keywords Bending instability of liquid jets Buckling of liquid jets Electrified liquid jets Electrospinning Elongational rheology Newtonian and rheologically complex liquids Quasi-one-dimensional equations of the dynamics of liquid jets Small and finite perturbations Viscoelastic polymeric liquids... 

A detailed theory of the bending instability of the electrified polymer jets in electrospinning was given in [9, 10] (see also the reviews [11, 23, 24] and references therein). Recasting the inequality (2.22) for the onset of the aerodynamic bending reveals that the destabilizing electric force overcomes the stabilizing effect of the surface tension if... 

Electrospinning It is cost-effective and gives long, continuous nanofibers. Jet instability control on fiber diameter... 

The electrical instability in the electrospinning process was compared to aerodynamic instabilities where partial differential equations of the aerodynamics of the fluid jet with electric field equations are used to describe the process. Many theoretical models have been used to describe the combination of a viscoelastic fluid driven by an electrical field. On the basis of Taylor studies and with the use of high-velocity cameras, it was proposed that the electrospinning... 

By considering axisymmetric instabilities of highly conducting viscoeleastic solutions of PEO, in the theoretical studies, a linear stability analysis combined with a model for stable electrospun jet was used to calculate the expected bead growth rate and the bead wave number for given electrospinning conditions. 

M M Hohman, G Shin, G Ruteledge, M P Brenner, Electrospinning, electrospraying and the instability of electrically forced jets . Part 1, Phys. Flui, 2001 13 2221. 

Shin, Y.M., Hohman, M.M., Brenner, M.P. and Rutledge, G.C. 2001a. Experimental characterization of electrospinning The electrically forced jet and instabilities. 42 ... 

---