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Polyaniline/nanocarbon (PANI/NC) nanocomposites have been prepared by in situ polymerization of aniline monomer in the presence of a stable colloidal solution of nanocarbon NC using ammonium persulfate as an initiator and silver ions (Ag+) as oxidizing agents to produce PANI/NC and PANI/NC/Ag2O nanocomposites, respectively. The morphological studies of the formed nanocomposites have been elucidated via transmission and scanning electron microscopes (TEM and SEM). Further characterization of the prepared nanocomposites has been done via infrared spectroscopy (IR), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), particle size distribution analysis (PSD), fluorescence microscope (FM), UV–VIS spectroscopy, and finally surface analysis. XRD results confirmed the presence of silver oxide Ag2O nanoparticles, and the obtained data is well matched with the JCPDS card number 76–1393 of silver oxide. XPS analyses have shown two prevailing characteristic peaks for Ag 3d5/2 and Ag 3d3/2 at 367.1 and 373 eV, respectively, representing Ag2O nanoparticles, which are matchable with the XRD analysis. The PSD analysis revealed that the sizes of the prepared nanocomposites are in the size range from 60 to 140 nm. The FM measurements showed luminescence from the prepared nanocomposites upon irradiation with different lights. This recommends that the fluorophores present in the prepared nanocomposites have the potential to both absorb and emit light. The AC conductivity and the dielectric permittivity of the obtained nanocomposites at room temperature and at different frequency ranges have been investigated. At higher frequency ranges, the maximum ac conductivity obtained was 1.06 × 10–2 and 2.5 × 10–2 S.Cm-1 for the PANI/NC and PANI/NC/Ag2O, respectively. As far as we know, these new nanocomposites with superior optical and electrical characteristics have not been described yet in the literature. [ABSTRACT FROM AUTHOR]

New efficient chelating polymers (CPs) based on waste polystyrene functionalized by itaconic acid moieties in absence and presence of montmorillonite clay have been prepared using high shearing effect homogenizer. The obtained CPs have been characterized using spectrophotometric and thermal analyses. The prepared CPs have been used as potential adsorbents for removal of different toxic metal ions from their aqueous solutions. The adsorption performance of the obtained CPs was found to match well with Langmuir adsorption isotherms. The highest sorption affinity of the obtained CPs toward different metal ions was for copper and lead. [ABSTRACT FROM AUTHOR]

We report on the development of efficient infrared-active core-shell Er2O3-Si nanoparticle architecture. Sub 3-nm H-terminated Si nanoparticles are used to reduce/deposit Er3+ ions on the nanoparticles, which in an aqueous environment simultaneously oxidize to produce the core-shells. Our results show strong cathodoluminance at 1543 nm while being able to resolve the Stark splitting. The strong luminescence afforded by the core-shell architecture in which the Si-Er interspacing drops appreciably supports a sensitive interspacing-dependent dipole-dipole energy transfer interaction model, while the hydrogenated silicon-core allows increased loading and reduced segregation of Er as in amorphous silicon material. The room temperature-wet procedure, with preprepared and -sorted Si nanostructures affords promising applications in electronic and optical technologies. [ABSTRACT FROM AUTHOR]

This work exhibits the synthesis and characterization of novel polymer/hybrid coatings for concrete protection. The coatings have been prepared by polymerization of vinyl acetate, butyl acrylate, or glycidyl methacrylate with hydroxyl ethyl methacrylate and toluidine as multiple shells in presence of poly methyl methacrylate (scrap) as seed particles and silica (natural sand) as inner core forming the corresponding C1, C2, and C3 coatings, respectively. The prepared polymer coatings have been characterized via Fourier transform-infrared spectroscopy, thermogravimetric analysis, transmission electron microscope, and SEM. The prepared coats have been tested on ready-made concrete slates. The polymer coatings have been applied with ease on dry concrete slates. Test results showed that the polymer coatings have good bonding strength with dry concrete surfaces ranging between 0.78 and 0.99 MPa. No failure was observed for more than 1 year with the coated concrete slates. The acid and base resistance as well as abrasion resistance of the coated concrete slates have been also evaluated and investigated. The performance of the prepared polymer coatings in 3% sulfuric acid and 20% sodium hydroxide solutions has proved the effectiveness of the prepared coatings in protecting the concrete slates. [ABSTRACT FROM PUBLISHER]

A new type of synthesis route for the preparation of conducting chelating polymer composites (CCPCs) based on waste polystyrene grafted with acrylic (AA) and maleic (MA) acids in the presence of montmorillonite clay was investigated. The prepared composites were characterized using various techniques including Fourier-transform infrared spectroscopy, thermogravimetric analysis, light microscopy and x-ray diffraction analysis. The prepared composites of different AA and MA weight percentage (wt%) have been used as adsorbents for removal of toxic copper ions from their aqueous solutions. The copper uptake by the CCPC grafted with AA was found to be much higher than that of the CCPCs grafted with MA. The key parameters that can affect copper ion uptake such as time and pH were also investigated, and it was found that the increase in pH highly enhanced the copper uptake. The study was further extended to measure the alternating current (AC) conductivities of the prepared composites and their copper complexes which proved that the AC conductivities of the copper-free composites are higher than the AC conductivities of the composites complexed with copper ions. [ABSTRACT FROM PUBLISHER]