Carbon nanotube-graft-poly(citric acid) nanocomposites

Novel biodegradable nanocomposites containing multi wall carbon nanotubes (MWCNT) and poly(citric acid) (PCA) were successfully synthesized. For preparation of nanocomposites, MWCNT was opened using a mixture of sulfuric and nitric acid and its derivative containing -COOH and -OH functional groups was obtained. Polycondensation of monohydrate citric acid in the presence of functionalized MWCNT in the melting state was lead to nanotube-graft-poly(citric acid) (CNT-g-PCA) nanocomposites. The degree of polymerization of grafted hyperbranched poly(citric acid) onto the CNTs was controlled using CNT/citric acid ratio. The CNT-g-PCA were soluble in water freely and stirring their water solution and silver nitrate at room temperature lead to the CNT-g-PCA containing encapsulated silver nanoparticles in their polymeric shell. The structure of nanocomposites was characterized by TEM, DLS and spectroscopy methods.