Page 28 - Tailoring Electrospinning Techniques for Regenerative Medicine - Marc Simonet
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CHAPTER 1
Table 1.3
Humidity
Increase Decrease
Influence of relative humidity on the fiber diameter.
Fiber diameter
Increase Decrease Increase Decrease
E ect
Skin formation on jet due to polymer precipitation36,66,69,71
Water absorption into jet, decreasing polymer concentration70,72,89 Faster solvent evaporation and jet solidification90
Reduced polymer precipitation e ect71
Figure 1.4 SEM pictures of electrospun fibers exhibiting di erent surfaces structuring (a) smooth polystyrene fibers, spun from Dimethylformamide at 24% rel. humidity98 (b) polystyrene fiber with axial wrinkels, spun from Dimethylformamide at 22% rel. humidity98, (a & b) adapted with permission from Macromolecules, 2009, 42, Copyright 2009 American Chemical Society, (c) PLGA with distinct surface pores, spun from Chloroform at high humidity, unpublished work (d) poly(e-caprolactone) fiber with radial features due to dissolution of the blended- in poly(ethylenexoide)96 adapted with permission from the Centre National de la Recherche Scientifique (CNRS) and The Royal Society of Chemistry. Scale bar on all images is 5 mm.
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