Syndiotactic Polystyrene Nanofibers Obtained from High-Temperature Solution Electrospinning Process

Electrospun syndiotactic Polystyrene (sPS) fibers with a diameter of 150-400 run were successfully prepared via high-temperature electrospinning of solutions with different concentrations in an o-dichlorobenzene solvent. From the polarized FTIR spectra, the sPS chains in the as-spun fibers were amorphous and exhibited a preferential chain orientation along the fiber axis. Upon thermal annealing at a temperature lower than 270 degrees C, sPS crystals with the alpha-form modification were developed, as revealed by the electron diffraction patterns of the individual fiber segments. The orientation factor of the (002) plane was determined to be 0.94-0.97, relatively independent of the annealing temperature. Solvent-induced crystallization readily took place in these submicrometer-sized Fibers, giving rise to the delta-form sPS crystals, as revealed by the FTIR spectra and WAX D patterns. The absorbed solvents Could subsequently be expelled by boiling in ethanol, leaving the cavities available for the next solvent treatment. In contrast with the bulk films, sPS fiber mats exhibit a promising application in chemical separation and water purification due to their large surface area as well is high solvent permeation resulting from its small-fiber diameter character.