Barb formation in electrospinning: Experimental and theoretical investigations

PVA nanofibers electrospun from solutions with relatively low polymer concentrations (below 8 wt%) tend to be no longer smooth, but display barbs which occur regularly spaced along the nanofiber length. Such structures are of interest for a number of technical applications, since they affect the fib...

Full description

Saved in:
Bibliographic Details
Published in:Polymer (Guilford) 2010-05, Vol.51 (12), p.2769-2778
Main Authors: Holzmeister, A., Yarin, A.L., Wendorff, J.H.
Format: Article
Language:English
Subjects:
Applied sciences
Barbed nanofibers
Charge
Charge (electric)
Electrical conductivity
Electrospinning
Exact sciences and technology
Instability
Machinery and processing
Mathematical models
Morphology
Nanofibers
Nonlinearity
Plastics
Polymer industry, paints, wood
Polyvinyl alcohols
Spinning
Technology of polymers
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:PVA nanofibers electrospun from solutions with relatively low polymer concentrations (below 8 wt%) tend to be no longer smooth, but display barbs which occur regularly spaced along the nanofiber length. Such structures are of interest for a number of technical applications, since they affect the fiber packing, pore sizes and the internal surfaces in the nanofiber nonwovens. This paper reports both, experimental and theoretical results, allowing to elucidate the mechanism responsible for barb formation. It is found that barb formation can be explained theoretically in terms of a relatively slow charge relaxation within the jet compared to the development of the secondary electrically driven instabilities which locally deform the jet surface. Both, the electric conductivity of polymer solutions and their viscoelasticity, are key parameters controlling the competition between charge relaxation and rate of growth of capillary and electrically driven, secondary, localized perturbations of the jet surface and thus barb formation. In this paper a nonlinear theoretical model is proposed that is able to mimic the main morphological trends recorded in the experiments. [Display omitted]
ISSN:0032-3861
1873-2291
DOI:10.1016/j.polymer.2010.04.005