Ultrasound-induced synthesis of an imidazolium based poly(ionic liquid) in an aqueous media: A structural, thermal and morphological study. 
Here we describe an efficient and rapid way for the polymerization of the 3-Octyl-1-vinylimidazolium Bromide using ultrasonic irradiation.  This way promoted high dispersion polymerization using a water-soluble free radical initiator namely 4,4'-Azobis (4-cyanopentanoic acid) and free of dispersant.  The ionic liquid monomer was prepared via quaternization of 1-vinylimidazole with octyl bromide also promoted by ultrasound.  The polymerization rates were compared with a conventional heating method and appeared to be higher in the case of the ultrasound method within a short reaction time.  The structural/morphological features and thermal properties of the obtained products were determined by different analytical techniques such as (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electronic microscopy (SEM, TEM), Fourier transform infrared spectroscopy (FTIR) and NMR Spectroscopy (1H and 13C NMR).  The morphology and the thermal behavior of the obtained poly(ionic liquid) were investigated and discussed.  The results indicated that self-assembled nanospherical particles of 30-80 nm in diameter were obtained through the ultrasound method, while on the other hand; worm-like/cylindrical agglomerated nanoparticles with irregular sizes 50-300 nm in diameter were obtained via the classical heating method.