Indirect functionalization of multiwalled carbon nano tubes through non-covalent interaction of functional polyesters

Synthetic approach was demonstrated to obtain a series of polyesters containing electron deficient internal alkyne units stemmed from acetylene dicarboxylic acid in the main backbone. Consequently, polyesters were made use of a polymeric platform in copper free cycloaddition reaction like, Huisgen type 1,3-dipolar cycloaddition in order to have pendant functional groups, pyrene, pyrene/COOH, pyrene/OH, and pyrene/C≡CH using organic azides. A pyrene pendant unit of these polyesters was non-covalently interacted with the surface of multiwalled carbon nanotubes (MWCNTs) via π–π stacking as shown by high-resolution transmission electron microscopy (HRTEM), thermogravimetric analysis (TGA) and UV–visible spectroscopy. Therefore, MWCNTs were indirectly functionalized using pre-functional polyesters that possess pendant functional groups: pyrene or pyrene together with -COOH, -OH, and -C≡CH. Moreover, the dispersion stability of modified CNTs was investigated in frequently used organic solvents.