Electrospinning is a method to produce nanofibers.

1. ELECTROSPINNING OF
NANOFIBERS
Presented by:
PREM KUMAR SR
4NI11ME088

2. OUTLINE:
• Introduction
• Background
 Apparatus
 Working principle
 Variables
 Fiber alignment
 Applications
• Future Research
• Reference

3. Introduction
• Nanofibers are created by a process called
electrospinning.
• Electrospinning is a major way to engineer (without self-
assembly) nanostructures that vary in:
▫ Fiber Diameter
▫ Mesh Size
▫ Porosity
▫ Texture
▫ Pattern Formation
Burger, Christian, et. al. Nanofibrous Materials and Their Applications. 2006. http://en.wikipedia.org/wiki/File:Taylor_cone_photo.jpg

4. An Example
• Take the distance between the
Earth and the Moon, L, to be
384,400 km.
• It takes only x grams of a polymer
fiber filament to make up this
distance
• ρ = 1 g cm-3 and the fiber diameter
d = 2r = 100 nm
• X = Vρ = πr2Lρ = π (50 nm)2
(380,000 km) (1 g cm-3 )
• ≈ 3 grams
Burger, Christian, et. al. Nanofibrous Materials and Their Applications. 2006.

5. Electrospinning

6. Schematic Representation of the Reactive
Electrospinning Apparatus
• Fibers are irradiated with UV light during spinning in order to
form crosslinked graft scaffolds

7. Electrospinning - Procedure
• An electrostatic potential is applied between a
spinneret and a collector
• A fluid is slowly pumped through the spinneret.
• The fluid is usually a solution where the solvent can
evaporate during the spinning.
• The droplet is held by its own surface tension at the
spinneret tip, until it gets electrostatically charged.
• The polymer fluid assumes a conical shape (Taylor
cone).
• When the surface tension of the fluid is overcome, the
droplet becomes unstable, and a liquid jet is ejected
Burger, Christian, et. al. Nanofibrous Materials and Their Applications. 2006.

8. Electrospinning Polymers
• The small size between the fibers allows the
capture of particles in the 100- to 300-
nanometer range
• That is the same size of viruses and bacteria
• Used as air-filter: Airplanes, office, etc.
Burger, Christian, et. al. Nanofibrous Materials and Their Applications. 2006.
Polymer Solvent Concentration Potential Application
Nylon 6,6 Formic Acid 10 wt% Protective Clothing
Polyurethanes Dimethylformamide 10 wt% Protective Clothing
Polycarbonate Dichloromethane 15 wt% Sensor, Filter
Polylactic Acid Dichloromethane 14 wt% Drug Delivery System

9. Nanofibers have large surface area per
gram

10. Electrospinning Variables
Burger, Christian, et. al. Nanofibrous Materials and Their Applications. 2006.

11. Fibre alignment
• A cylinder collector with high rotating speed
• A thin wheel with sharp edge
• An auxiliary electrode/electrical field

12. Applications
Burger, Christian, et. al. Nanofibrous Materials and Their Applications. 2006.

13. Improvements and Further Research
• Develop more precise
electrospinning techniques
▫ Mechanisms of electrospinning
 Growth rates
 Bending Instability
▫ Producing nanofabrics with
specific mechanical properties.
▫ Creating 3-dimensional shapes
 Capable of being used in controlled
release of drugs.
Burger, Christian, et. al. Nanofibrous Materials and Their Applications. 2006.

14. Improvements and Further Research
• Optimization of parameters
▫ Intrinsic properties of solution
 Polarity, surface tension of solvent,
MW of polymer, etc.
• Safety
▫ Solvents
 Dangerous to health and environment
"Electrospin Nanofibers for Neural Tissue Engineering."
http://www.rsc.org/ejga/NR/2010/b9nr00243j-ga.gif

15. References
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coalesces. Chemical Engineering Science 1985; 40(1):117–29.
• [2] Adanur S, Liao T. Computer imulation of mechanical properties of nonwoven
geotextiles in soil-fabric interaction. Textile Res J 1998; 68:155–62.
• [3] Angadjivand SA, Schwartz MG, Eitzman PD, Jones ME. US patent, 6375886. 2002.
• [4] Athreya SA, Martin DC. Impedance spectroscopy of protein polymer modified silicon
micromachined probes. Sensors and Actuators a—Physical 1999; 72(3):203–16.
• [5] Bognitzki M, Czado W, Frese T, Schaper A, Hellwig M, Steinhart M, et al.
Nanostructured fibres via electrospinning. Adv Mater 2001; 13:70–2.
• [6] Demir MM, Yilgor I, Yilgor E, Erman B. Electrospinning of polyurethane fibres.
Polymer 2002; 43:3303–9.