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.

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A simple method has been developed for decorating multi wall carbon nanotubes (MWCNTs) with palladium and silver nanoparticles. In this method, MWCNT was opened and functionalized using nitric and sulfuric acid mixture. Then citric acid was polymerized in the presence of functionalized MWCNT and MWCNT-graft-poly (citric acid) (MWCNT-g-PCA) was obtained. The mixing of MWCNT-g-PCA with metal salts, such as palladium chloride and silver nitrate, leads to encapsulation of metal nanoparticles in the polymeric shell ( MWCNT/Pd, AgNPs ). The structure of MWCNT/Pd and AgNPs were characterized by usual spectroscopy and microscopy methods. The influence of nanoparticles on the electrical conductivity of MWCNT was also investigated.

Polycaprolactone-polylactide block copolymers (PCL-block-PLA) were grafted onto filled multi-wall carbon nanotubes (MWCNT) successfully. In this synthesis, MWCNTs were opened and functionalized, and then they were filled by silver nanoparticles. The filled MWCNT were used as macroinitiator for ring opening polymerization of ε-caprolactone and L-lactide. Then the end hydroxyl functional groups of MWCNT-graft-PCL or MWCNT-graft-PLA were used as initiator for ring opening polymerization of lactide and ε-caprolactone and MWCNT-graft-PCL-block-PLA or MWCNT-graft-PLA-block-PCL were obtained, respectively. Length of grafted copolymer chains onto the MWCNT was controlled using CNT/monomer ratio. Nanocomposites' properties depend on the length of polymer blocks strongly. Structure of nanocomposites was evaluated by TEM and spectroscopy methods.

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The cross section of two alternating concentric double silica-gold nanoshell (DSGNS) is obtained as a function of wavelength. Numerical calculations show that two alternating concentric DSGNSs display two separated scattering peaks that the intensity and position of the scattering peaks depend on two gold shells thicknesses and silica layer thickness between them. By varying thicknesses of the layers of the gold shells, two alternating concentric DSGNS can be designed with the scattering peak from the visible to infrared regions of the spectrum.