Polyaniline (PANI), poly(o-anisidine), and poly[aniline-co-(o-anisidine)] were synthesized by chemical oxidative polymerization with ammonium persulfate as an oxidizing reagent in an HCl medium. The viscosities, electrical conductivity, and crystallinity of the resulting polymers (self-doped forms) were compared with those of the doped and undoped forms. The self-doped, doped, and undoped forms of these polymers were characterized with infrared spectroscopy, ultraviolet-visible spectroscopy, and a four-point-probe conductivity method. X-ray diffraction characterization revealed the crystalline nature of the polymers. The observed decrease in the conductivity of the copolymer and poly(o-anisidine) with respect to PANI was attributed to the incorporation of the methoxy moieties into the PANI chain. The homopolymers attained conductivity in the range of 3.97 ϫ 10 Ϫ3 to 7.8 S/cm after doping with HCl. The conductivity of the undoped forms of the poly[anilineco-(o-anisidine)] and poly(o-anisidine) was observed to be lower than 10 Ϫ5 J/S cm Ϫ1. The conductivity of the studied polymer forms decreased by the doping process in the following order: self-doped 3 doped 3 undoped. The conductivity of the studied polymers decreased by the monomer species in the following order: PANI 3 poly[aniline-co-(o-anisidine)] 3 poly(o-anisidine). All the polymer samples were largely amorphous, but with the attachment of the pendant groups of anisidine to the polymer system, the crystallinity region increased. The undoped form of poly[aniline-co-(o-anisidine)] had good solubility in common organic solvents, whereas doped poly[aniline-co-(oanisidine)] was moderately crystalline and exhibited higher conductivity than the anisidine homopolymer.

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Dextran-coated iron oxide nanoparticles (DIONPs) with appropriate surface chemistry exhibit many interesting properties that can be exploited in a variety of biomedical applications such as magnetic resonance imaging (MRI) contrast enhancement, tissue repair, hyperthermia, drug delivery and in cell separation. This paper reports the experimental detail for preparation, characterization and investigation of thermal and dynamical mechanical characteristics of the dextran-coated FeO magnetic nanoparticles. In our work, DIONPs were prepared in a 1:2 ratio of Fe(II) and Fe(III) salt in the HCl solution with NaOH at given temperature. The obtained dextran-coated iron-oxide nanoparticles structure-property correlation was characterized by spectroscopic methods; attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and XRD. Coating dextran on the iron-oxide proof of important peaks can be seen from the ATR-FTIR. Dramatic crystallinity increment can be observed from the XRD pattern of the iron-oxide dextran nanoparticles. The thermal analysis was examined by differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and differential thermal analysis (DTA). Dynamical mechanical properties of dextran nanoparticles were analysed by dynamic mechanical analysis (DMA). Thermal stability of the iron oxide dextran nanoparticles is higher than that of the dextran.

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