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We report here a novel in-situ synthetic method for the preparation of poly (o-methoxyaniline) and palladium nanoparticle composite material. Ortho-Methoxyaniline and palladium acetate were used as the precursors; during the reaction o-methoxyaniline was oxidized and forms poly (o-methoxyaniline) and palladium acetate is reduced forming palladium nanoparticles. IR and Raman spectra provide information on the structure of the polymer. The TEM and SEM analysis are used to determine the size of the nanoparticles and the morphology of the polymer respectively.
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PMID:Formation of palladium nanoparticles in poly (o-methoxyaniline) macromolecule fibers: an in-situ chemical synthesis method. 1652 66

As with all nanomaterials, a large fraction of the atoms in carbon nanotubes (CNTs) reside at or near the surface. Consequently, surface chemistry will play a crucial role in determining the fate and transport of CNTs in aquatic environments. Frequently, oxygen-containing functional groups (surface oxides) are deliberately grafted into the CNT surface to promote colloidal stability. To study the influence that both the oxygen concentration and the oxygen functional-group distribution have on the colloidal stability of multiwalled carbon nanotubes (MWCNTs), a suite of oxidized MWCNTs (O-MWCNTs) were created using different oxidizing agents and reaction conditions. Stable colloidal suspensions were prepared by low-power sonication of O-MWCNT powders in Milli-Q water. Results from TEM, AFM, DLS, and XPS measurements revealed that, irrespective of the surface chemistry, the colloidal suspensions were composed of individual nanotubes with comparable length distributions. The critical coagulation concentrations (CCC) of O-MWCNTs that exhibited different surface chemistries were measured with time-resolved dynamic light scattering (TR-DLS) using NaCl as the electrolyte. Over a range of environmentally relevant pH values, linear correlations were found to exist between the CCC, total oxygen concentration, and surface charge of O-MWCNTs. In contrast to surface charge, electrophoretic mobility did not prove to be a useful metric of colloidal stability. Information obtained from chemical derivatization studies, carried out in conjunction with XPS, revealed that the distribution of oxygen-containing functional groups also influences the colloidal stability of O-MWCNTs, with carboxylic acid groups playing the most important role. This study highlights the fact that quantitative relationships can be developed to rationalize the influence of surface chemistry on the behavior of nanomaterials in aquatic environments.
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PMID:Influence of surface oxides on the colloidal stability of multi-walled carbon nanotubes: a structure-property relationship. 1958 26