کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5186420 | 1381104 | 2009 | 8 صفحه PDF | دانلود رایگان |
This study reports the synthesis of polyaniline (PANI) nanotubes with the introduction of methanol in aqueous solutions. SEM images indicate that well-dispersed PANI nanotubes are produced when the concentration of methanol increases up to 1Â M. On the other hand, polymers primarily form irregular agglomerates when only monomers and oxidant are used in the absence of methanol. Transmission electron microscopy (TEM) reveals that the resulting nanotubes have an outer diameter of about 200Â nm and an inner diameter of 0-50Â nm. Fourier transform infrared (FT-IR) spectra indicate that the intermediate samples obtained at a reaction time of around 60Â min have a structure consisting of a head of phenazine-like units and a tail of para-linked aniline units. Ultraviolet-visible (UV-vis) spectra indicate that emeraldine salt polyaniline (ES-PANI) appears in sequence as the reaction time reaches 75Â min. At the time interval of 60-75Â min, the self-curling behavior of the PANI intermediates first appears at 60Â min, and PANI nanotubes can be observed starting at 75Â min. This is the first study to observe this self-curling process and propose that it explains the formation of PANI nanotubes. Noteworthily, the nanotubes transform into irregular agglomerates after a de-doping process.
Journal: Polymer - Volume 50, Issue 3, 28 January 2009, Pages 775-782