Facile synthesis of poly(p-phenylenediamine)/MWCNT nanocomposites and characterization for investigation of structural effects of carbon nanotubes

Poly(p-phenylenediamine) (PpPD)/carboxylic acid-functionalized multiwalled carbon nanotubes (c-MWCNTs) nanocomposites were prepared by chemical oxidative polymerization using potassium persulfate (K(2)S(2)O(8)) as an oxidant. Field-emission scanning electron microscopy (FE-SEM) and field-emission transmission electron microscopy (FE-TEM) showed that a tubular layer of PpPD was coated on the surface of carbon nanotubes with a thickness of 10-20 nm. FT-IR analysis provided an evidence for the formation of nanocomposites. The thermal stability of nanocomposites was improved by addition of c-MWCNTs as confirmed by thermogravimetric analysis (TGA). XRD spectra showed that the crystalline nature of PpPD was not affected much by the addition of c-MWCNTs. As the content of c-MWCNTs was increased, the electrical conductivity of the nanocomposites increased due to the interaction between polymer and nanotubes that enhances electron delocalization.