PREPARATION AND PROPERTIES OF REVERSIBLE POLYMERS AND SELF-ASSEMBLY OF CARBON NANOTUBES

Abstract

<p>A series of bismaleimide and bisfuran monomers were synthesized and then combined to produce thermally reversible polymers. Reversibility was demonstrated through multiple heating and cooling cycles, and verified using ¹H NMR spectroscopy. Variation of the spacer chemistry in the monomers was found to profoundly influence the physical properties of the resulting polymers. A tripodal maleimide and furan system was then synthesized, but it was found that the incorporation of cross-linking into the polymer network did not significantly alter the mechanical properties of the resulting polymers.</p> <p>Dilute solutions of polystyrene (PS)/poly(methyl methacrylate) (PMMA) blends containing PS- or PMMA-functionalized single-walled carbon nanotubes (SWNT) were spin cast and annealed at 180°C for 12 h. Characterization of the annealed films by scanning Raman spectroscopy confirmed that the migration of the nanotubes in the films could be controlled using the appropriate functionality on the nanotubes, thus the PS-functionalized nanotubes were found to migrate to the PS domains, while the PMMA-functionalized nanotubes migrated to the PMMA domains.</p> <p>SWNTs were then functionalized using linear reversible polymers, resulting in significant solubilization of the nanotubes. Heating of this solution resulted in the collapse of the DA polymer, and precipitation of the dissolved nanotubes, illustrating the reversible nature of the polymers, and their influence on carbon nanotube solubilization.</p>