1/21/2011
Electrospinning of Concentrated Polymer Solutions
(10743–10746) Macromolecules 43 #24 (2010)
No Abstract (RDC 1/19/2011)

12/17/2010
Atmospheric plasma treatment of pre-electrospinning polymer solution: A feasible method to improve electrospinnability
( 115–122)Journal of Polymer Science B: Polymer Physics 49, #2 (2011)
Shu et al showed the conductivity, viscosity, and surface tension of PEO solutions increased after plasma treatment, and the plasma effect remained longer when the solution concentrate increased.  Atmospheric plasma treatment improved the electrospinnability of PEO solutions and led to less beads and finer diameter distribution in the resultant nanofibers.   (RDC 12/21/2010)

12/3/2010
How to manipulate the electrospinning jet with controlled properties to obtain uniform fibers with the smallest diameter?—a brief discussion of solution electrospinning process
(111-123) Journal of Polymer Research 18  #1 (2011)
Wang et al studied the electrospinnability of of five different polymer solutions, namely; polystyrene (PS), polyacrylonitrile (PAN), polyhydroxybutrate (PHB), poly(D-L-lactic acid) (PLA), and Nylon6,  A minimum polymer concentration 1.0–2.0 times larger than the entanglement concentration was required to prepare the bead-free fibers. Using this strategy, uniform PS fibers with the lowest ever diameter of 15 nm were successfully obtained using an MW of 3 × 107g/mol at a concentration of 0.1 vol.%.  A feasible route to predict the as-spun fiber diameter produced by the manipulation of the electrified jet is provided by experimentally measuring the jet diameter and numerically calculating the electric field for the jet whipping process.  (RDC 12/9/2010)

10/29/2010
Barb formation in electrospinning: Experimental and theoretical investigations 
(Pages 2769-2778) Polymer 51 #12 (2010)
Holzmeister et al found that electrospinning PVA nanofibers electrospun from low contration solutions (below 8 wt%) tend to be no longer smooth, but display barbs which occur regularly spaced along the nanofiber length.  Barb formation is explained as a result of relatively slow charge relaxation within the jet compared to the development of the secondary electrically driven instabilities which locally deform the jet surface.  (RDC 12/22/2010)

The role of interfacial viscoelasticity in the stabilization of an electrospun jet
(Pages 2611-2620) Polymer 51 #12 (2010)
Regev et al have proposed that a complex jet structure, composed of a liquid core surrounded by a viscoelastic interface, is formed during the spinning process, where the surface viscoelasticity is responsible for the jet stabilization.  These rheological properties of the surface are experimentally verified using novel interfacial rheometry.  It is also shown that the surface viscoelasticity is further enhanced by varying the protein conformation (unfolding), as well as its concentration in solution.  (RDC 12/22/2010)

Electrospinning fabrication of partially crystalline bisphenol A polycarbonate nanofibers: The effects of molecular motion and conformation in solutions 
(2887-2896) Polymer 51 #13 (2010)
Liao et al used a combination of a centrifugal field (1800 rpm) and an electrostatic field (25 kV) to form the nanofibers.  The BPAPC assumed a denser, more worm-like chain conformation in THF solvation.  (RDC 12/22/2010)

Formation and characterization of core-sheath nanofibers through electrospinning and surface-initiated polymerization 
(4368-4374) Polymer 51 #19 (2010)
Ji et al of North Carolina State University fabricated core-sheath nanofibers, composed of polyacrylonitrile (PAN) core and polypyrrole (PPy) sheath with clear boundary between them by electrospinning PAN/FeCl3·6H2O bicomponent nanofibers and the subsequent surface-initiated polymerization in a pyrrole-containing solution.  By adjusting the concentration of FeCl3·6H2O, the surface morphology of PPy sheath changed from isolated agglomerates or clusters to relatively uniform thin-film structure.  The PPy sheath played a role of inhibitor and retarded the complex chemical reactions of PAN during the carbonization process.  (RDC 12/19/2010)