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In this study, chitosan (Ch) is adapted via green methodology including sonication induced crosslinking with different weight ratios of erythritol (Er) from (Ch-Er)1 to (Ch-Er)4. The products were casted in the form of thin films. The chemical modification was proved via FTIR spectroscopy. Then, the modified products were verified via an atomic force microscopy (AFM) investigation for their topography and surface properties. The data revealed that the optimized sample was (Ch-Er)3. This sample was further modified by different weight ratios of graphene oxide 0.1, 0.2, 0.4, and 0.8 wt./wt. (symbolized as (Ch-Er)3GO1, (Ch-Er)3GO2, (Ch-Er)3GO4, and (Ch-Er)3GO8 respectively). The prepared samples were investigated by different analytical tools. Then, the adjusted sample (Ch-Er)3GO2 was irradiated by electron beam (e-beam) at 10 and 20 kGy of irradiation doses to give samples (Ch-Er)3GO2R10 and (Ch-Er)3GO2R20, respectively. The AFM data of the irradiated samples showed that the pore size decreases, and surface roughness increases at higher energy e-beam due to the formation of more crosslinking points. The optimum samples of the prepared formulations were tested as sorbent materials for simultaneous elimination of methylene blue (MB) dye and mercury cation (Hg2+) from simulated solutions. The maximum removal of both MB dye and Hg2+ cation was achieved by (Ch-Er)3GO2R10 (186.23 mg g−1 and 205 mg g−1) respectively. Graphical abstract

A series of diols and normal alcohols were dispersed in some polymeric matrices, namely, polystyrene (PS), polyethylene (PE), and poly(methyl methacrylate) (PMMA). The dielectric properties of these systems were investigated in the frequency range of 10 2 -10 5 Hz at a room temperature of 25 o C. The experimental data were analyzed according to the Fröhlich equation into two relaxation processes: The first relaxation in the lower-frequency range could be attributed to the Maxwell-Wagner effect as a result of the difference in permittivities and conductivities of the investigated systems. The second relaxation in the higher-frequency range could be attributed to an intramolecular motion involving the rotation of various segments of the chain about the C-C bond accompanied by movement of the main dipoles for either diols or alcohols. The presence of the phenyl ring in the PS matrix may hinder such rotation when compared with the other matrices. The dielectric properties were also investigated for PMMA blended with either PS or PE at different ratios before and after the addition of small quantities of ethanediol. The interaction that might be expected between PMMA and PS in the blend may affect the rotation of the ethanediol chain in the blend matrix. The dielectric data as well as the data obtained from the calculated heat of mixing show that the investigated blends are incompatible. The addition of ethanediol to such blends gives the possibility that a large number of dipoles can be impregnated into the blend matrix and the problem of phase separation could be solved.

Poly o-anisidine (POA) was prepared by chemical oxidation polymerization, and the nanocomposite of this polymer was mixed with different nanopowder metal oxides. The size and morphology of these synthesized POA/nanocomposites were shown using a transmission electron microscope (TEM). Fourier-transform infrared (FTIR) spectroscopy has been used to investigate the microstructure of the synthesized POA/nanocomposites. Thermal stability thermogravimetric analysis (TGA) and electrical conductivity of POA/nanocomposites were studied in the temperature range 40-120 C. It was found that the nanopowder metal oxides improve the thermal stability of POAs, except TiO 2, while the POA/CuO nanocomposite has the most thermal stability. Also the thermal stability is increases when the temperature is increased. The POA/nanocomposites reveal enhanced conductivity compared to conventional bulk POA. The highest electrical conductivity is obtained when the polymer mixes with CuO.

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