Ternary polybenzoxazine/POSS/SWCNT hybrid nanocomposites stabilized through supramolecular interactions

Abstract

In this study we linked zero-dimensional polyhedral oligomeric silsesquioxane (POSS) with one-dimensional single-walled carbon nanotubes (SWCNTs) as dual-dimensional nanohybrid complexes within polybenzoxazine matrices, stabilized through noncovalent supramolecular interactions. First, we synthesized a new bifunctionalized benzoxazine (Py-Bz-T), presenting thymine (T) and pyrene (Py) units, that displayed excellent thermal properties after thermal curing, because its T moieties increased the physical cross-linking density. Second, we prepared Py-Bz-T/OBA-POSS [octuply adenine (A)-functionalized POSS] nanocomposites and investigated, using nuclear magnetic resonance and Fourier transform infrared spectroscopies, the multiple hydrogen bonding A⋯T interactions between Py-Bz-T and OBA-POSS. Finally, we prepared Py-Bz-T/OBA-POSS/SWCNT ternary hybrid complexes dispersed in THF, stabilized through both multiple hydrogen bonding and π–π stacking interactions. Transmission electron microscopy revealed that the SWCNTs were highly dispersed and covered by the Py-Bz-T/OBA-POSS nanocomposites; these ternary hybrid complexes were stabilized through π–π interactions between Py-Bz-T/OBA-POSS and the SWCNTs, as evidenced using fluorescence spectroscopy.