Fyzikální principy tvorby nanovláken 11. Kapalinová tryska D.Lukáš 2010

Donghua University, Shanghai, China Reference: Xiao-Hong Quin & col Donghua University, Shanghai, China Effect of LiCl on electrospinning of PAN polymer solution: theoretical analysis and experimental verification Polymer, www.elsevier.com/locate/polymer

z Liquid density Volume flow rate Rovnice kontinuity, zákon zachování hmoty Applied electric field Surface Bulk + + + Rovnice kontinuity pro náboj El. current r u Surface density of the charge + + + Dimensionless conductivity + +

Bernoulli equation Zákon zachování energie Electrostatic surface force Viscous force

Scaling and dimensionless analysis mass current Allometric relation energy

m=? Nonlinear differential equation

z + + + r u + + + + +

Whipping part of the jet

a b Figure 4.4. Loops in unstable region of jet, caught on a slide glass -(a) PVA jet, (b) PEO jet.

Figure 4.6. Schematic diagram showing the Pendulum mechanism: (1) ground collector, (2) pendulum and (3) spinning electrode with a polymer.

a b Figure 4.5. Instability of Polyethylene-oxide jet - Exposed with two various exposure times of 1 ms and 18 ns.