Crystallization kinetics of PVDF filled with multi wall carbon nanotubes modified by amphiphilic ionic liquid

The special electric properties of the poly(vinylidene fluoride) (PVDF) is strongly dependent on its crystalline structural morphology. In this study, modification in the crystal structure of PVDF was achieved by utilizing the long alkyl chain ionic liquid (1-hexadecyl-3-methylimidazolium bromide, [C(16)mim][Br]) and ionic liquid modified multiwalled carbon nanotubes (MWCNT). The developed crystal pattern was analyzed by XRD and the compatibility and dispersion characteristics of MWCNT in the matrix was observed by FESEM. The isothermal and non-isothermal crystallization kinetics were studied by DSC and different models namely; Avrami, Jeziorny and Ozawa were applied to fit the data. The results demonstrate that crystal structure of PVDF is significantly changed and the dispersion of MWCNT was enhanced with the addition of ionic liquid (IL). Kinetically, the crystallization was influenced and became fast due to the presence of [C(16)mim][Br] at the PVDF/MWCNT interface. Furthermore, the data well fitted in the model with significant linearity. The positive effect on the crystallization of PVDF may be ascribed to not only due to the existence of pi-cation interaction between the imidazolium cation and the aromatic multiwall carbon nanotubes structure, but also due to the electrostatic interaction between the > CF2 of the polymer backbone and imidazolium cation, which speed up the crystallization kinetics.