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Multi-walled carbon nanotubes (CNTs) were functionalized on treatment with nitric acid and the surface-modified CNT was characterized using Fourier transform infrared spectroscopy (FTIR). Isotactic polypropylene (iPP)/CNT composites at different CNT loadings (i.e., 0.1, 0.25, 1.00, and 5.00 wt%) were prepared by melt blending in a mini blender. The differential scanning calorimetric (DSC) studies showed the nucleating effect of CNTs on the crystallization behavior of iPP. Results of X-ray diffraction studies are in conformity with the results of DSC studies. Results of stress–strain measurements reveal that Young's modulus increases, while elongation at break decreases with increase in CNT loading and the ductility of the composites is adversely affected at high loading of CNTs (>1.0 wt%). Functionalization of CNTs causes an improvement in Young's modulus, at all loadings studied, but elongation at break increases only up to 0.25%. At higher loading, the elongation at break drops down. Storage modulus increases with increase in CNT loading and the effect is greater in the case of functionalized CNTs. Tan δ shows a decrease with increase in CNT loading, but the effect is less pronounced at high CNT loading (>0.1 wt%). [ABSTRACT FROM PUBLISHER]

In this work, multiwall carbon nanotubes (MWCNT) were functionalized with phenol and characterized by using Fourier transform infrared spectroscopy (FTIR). Isotactic polypropylene (iPP)/MWCNT composites of both the unfunctionalized and functionalized MWCNT were prepared by melt blending in a miniextruder at different loadings of nanotubes (i.e., 0.1, 0.25, 1.0, and 5.0 wt%). The tensile properties of the composites were found to increase with increase in nanotube loading with a maximum in Young's modulus being achieved at 1.0 wt% loading of phenol functionalized MWCNT. The differential scanning calorimetry (DSC) studies reveal the nucleating effect of MWCNT on the crystallization of iPP. Percentage crystallinity was found to increase on phenol functionalization of MWCNT. Results of X-ray diffraction studies of the composites are in conformity with that of DSC studies. Dynamic mechanical studies reveal that the functionalized MWCNT causes many fold increase in the storage modulus, and the effect is pronounced in the case of functionalized MWCNT. POLYM. ENG. SCI. 2012. © 2011 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Abstract: Nanostructured tin dioxide (SnO2) is synthesized in the form of colloidal sol. Aniline monomer is polymerized in colloidal sol of SnO2 to prepare inorganic–organic hybrid nanocomposites. Optical band gap increases from 3.74 eV to 4.23 eV with increase of polyaniline concentration. The observed nonlinear current–voltage characteristics are satisfactorily explained using the Schottky type barriers. The temperature dependence of conductivity reveals three dimensional Mott''s hopping process. [Copyright &y& Elsevier]

Abstract: Conducting polypyrrole-wide band gap semiconducting silica (SiO2) nanocomposites are prepared by polymerizing pyrrole in the presence of colloidal silicon oxide sol. The nanocomposites are characterized by Fourier transform infrared spectrometer and scanning electron microscope. Three dimensional variable range hopping conduction process is involved in electric conduction. The current density satisfies the power law, , with at voltage . Optical absorption spectra reveal that the transition of polypyrrole shifts from 3.9 eV to 4.58 eV with increase of silica concentration. [Copyright &y& Elsevier]

Presents a study that examined the mixed curing behavior of chlorosulfonated polyethylene with a combination of metal oxide and peroxide. Methodology; Results; Discussion.