Core-Sheath Nanofibers

M. Wei, J. Lee, B. Kang, and J. Mead, Preparation of core-sheath nanofibers from conducting polymer blends, Macromolec. Rapid Commun., 26, 1127-1132 (2005). 

Core-sheath nanofibers of PEG-PLA and PEG can be prepared by electrospinning a water-in-oil emulsion in which the aqueous phase consists of a PEO solution in water and the oily phase is a chloroform solution of an amphiphilic PEG-PLLA diblock copolymer. The fibers obtained are composed of a PEO core and a PEG-PLA sheath with a sharp boundary in between. By adjusting the emulsion composition and the emulsification parameters the overall fiber size and the relative diameters of the core and the sheath can be changed. As shown in Fig. 5.15, a mechanism is proposed to explain the process of transformation fi-om the emulsion to the core-sheath fibers, i.e., the stretching and evaporation induced de-emulsification. In principle, this process can be applied to other systems to... 

Core-sheath nanofibers of PVDF (polyvinylidiene fluoride) around a polyimide core The nonwoven separators show better wettability with polar solvents, better thermal stability, better rate capability, and better cycle life compared to conventional PP separators. 

Jo E, Lee S, Kim KT, Won YS, Kim HS, Cho EC, Jeong U (2009) Core-sheath nanofibers containing colloidal arrays in the core for programmable multi-agent delivery. Adv Mater 21 968-972... 

How can hollow and core-sheath nanofibers be made by electrospinning ... 

Muthiah, R, Hsu, S.-H., Sigmund,W., 2010. Coaxially electrospun pvdf-teflon af and teflon af—pvdf core—sheath nanofiber mats with superhydrophobic properties. Langmuir 26. 

Srivastava Y, Loscertales 1, Marquez M, Thorsen T (2008) Electrospinning of hollow and core/sheath nanofibers using a microfluidic manifold. Microfluid Nanofluid 4 245-250... 

FIGU RE 2.6 Schematic representation of the coaxial electrospinning system for the formation of core/sheath nanofibers. 

McCann et al. [50] described the use of electrospinning in the fabrication of polymeric, ceramic, and composite nanofibers with core-sheath, hollow-fiber, or porous structure, as well as the efforts made to improve their morphological homogeneity, functionality, and device performance. Figure 12.9a shows the schematic diagram for the fabrication of core-sheath nanofibers with a coaxial spinneret, which was used by McCann et al. [50]... 

FIGURE 12.9 (a) Schematic diagram for the fahrication of core-sheath nanofibers with a... 

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