Solution-electrospun poly(ethylene terephthalate) fibers: Processing and characterization

Chi Wang, Ming Feng Lee, Yi Jiun Wu

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

Electrospun poly(ethylene terephthalate) (PET) fibers were prepared from a trifluoroacetic acid (TFA)-based solvent. Rheological studies revealed the concentration (φ) dependence of the specific viscosity (ν sp) to be ν sp ∼ φ 3.7 for PET/TFA solutions in the entangled regime. The determined entanglement concentration (φ e) was higher using a lower-molecular-weight PET. To obtain bead-free fibers, the minimum concentration for the electrospinning was 0.8-1.0φ e owing to the high volatility of TFA solvent, which significantly enhanced the chain network strength during jet whipping. The double-logarithmic plots of the jet (d j) and fiber (d f) diameters versus the zero-shear viscosity (ν 0) revealed that two scaling laws existed for the present solutions, i.e., d j ∼ ν 0 0.06 and d f ∼ ν 0 0.77. The microstructural evolution of the electrospun PET fibers from stepwise annealing to crystal melting was investigated by simultaneous small-angle X-ray scattering (SAXS)/wide-angle X-ray diffraction (WAXD) measurements using synchrotron radiation sources. The conformer transformation from gauche to trans was monitored by in-situ Fourier transform infrared spectral measurement. In the absence of any WAXD reflection, the as-spun PET fibers possessed a SAXS scattering peak, indicating the presence of a mesomorphic phase with an interdomain distance of 6.8 nm. At annealing temperatures (T a) higher than 100 °C, the mesomorphic phase gradually transformed into imperfect triclinic crystals and reached its saturation at 130 °C. Further increased T a perfected the triclinic structure without altering fiber crystallinity until the initial crystal melting at 218 °C, at which a significantly increased long period was detected. When the electrospun PET fibers were embedded in an isotactic polypropylene (iPP) matrix, surface-induced crystallization occurred to develop a transcrsytalline layer of iPP monoclinic crystals at the interface.

Original languageEnglish
Pages (from-to)7939-7947
Number of pages9
JournalMacromolecules
Volume45
Issue number19
DOIs
Publication statusPublished - 2012 Oct 9

All Science Journal Classification (ASJC) codes

  • Organic Chemistry
  • Polymers and Plastics
  • Inorganic Chemistry
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Solution-electrospun poly(ethylene terephthalate) fibers: Processing and characterization'. Together they form a unique fingerprint.

  • Cite this