Electrospinning of Polylactide and Its Composites With Carbon Nanotubes
writer：Yang, Tao，Wu, Defeng(*)，Lu, Liangliang，Zhou, Weidong，Zhang, Ming
keywords：Electrospinning etc.
source：期刊
specific source：Polymer Composites
Issue time：2011年
Electrospinning of the biodegradable polylactide (PLA)
and its composites containing carbon nanotubes (CNTs)
was studied in terms of solution concentrations and solvents
effects as well as CNT loadings. The results reveal
that the PLA fibers obtained from the solutions using
the mixed solvents of chloroform/assistant solvent (v/v
3/1) show better morphologies than those from the solutions
using chloroform as the single solvent. This is due
to the synergistic effect by the improved conductivity
and altered viscosity with addition of assistant solvent.
Moreover, the surface structure of fibers depends on the
volatility of assistant solvents strongly. Using volatile acrylonitrile
or acetone as the assistant solvents, the columned
fibers with porous surface structure are
obtained; while the flat fibers with fluted surface are
formed using nonvolatile dimethyl sulfoxide as the assistant
solvents. As for electrospinning of the PLA/CNT
composites, the morphology of obtained fibers is closely
related to the dispersion of CNTs in the fibers. At low
loading levels, the CNTs can be well embedded in the
PLA matrix and oriented along the fiber axis, forming
nanowire structure. At high loading levels, the CNTs are
mainly dispersed as entangled bundles along the fiber
axis, and as a result, the obtained fibers show tortuous
or misshaped morphologies. Compared with that of the
neat PLA fibers, the overall morphologies of the composite
fibers are more or less degraded because the
presence of some small CNT aggregates in the solutions
easily leads to the formation of beaded fiber structure
during electrospinning. The conductivity of the obtained
composite fiber mats was further studied in terms of
CNT loadings.