Phase Separation in Electrospun Nanofiber Controlled by Crystallization Induced Self-assembly
作者：W. Huang, M. J. Wang, C. L. Liu, J. You, S. C. Chen*, Y. Z. Wang, Y. Liu*
關(guān)鍵字：electrospinning, nanofiber, crystallization induced self-assembly, phase separation, poly(p-dioxanone)
論文來源：期刊
具體來源：Journal of Materials Chemistry A
發(fā)表時間：2014年
Nanofibers from poly(lactic
acid) (PLA) homopolymer and poly(p-dioxanone)-b-poly(ethylene glycol) multi-block
copolymer (PPDO-b-PEG) with different phase separation morphologies depending
on the crystallization induced self-assembly of PPDO-b-PEG are prepared by single
spinneret electrospinning. Mixing solvents of chloroform/dimethyl formamide
(CHCl3/DMF) with different composition are used for controlling the
crystallization of PPDO block and therefore the phase separation in obtained
nanofibers. The crystallization of PPDO block has very important influence on
the morphology of the PPDO-b-PEG nanoparticles in spinning solution. In
spinning solution with low DMF content, nanoparticles with irregular shape and
incompact inner structure are formed because the degree of crystallization of
PPDO block is relatively low, and a discontinuous sea-island phase separation
is formed in the obtained electrospun nanofibers. Meanwhile, in spinning
solution with high DMF content, the copolymer can form flake-like nanoparticles
with relatively high degree of crystallization. The flake-like shape is in favor
of compact aggregation of PPDO phase during formation of the nanofibers, and a continuous
core-shell phase separation of the nanofibers is obtained.