The oxidative chemical polymerization of o-phenylenediamine (OPDA) was studied in hydrochloric acid solution using potassium dichromate as oxidant at 5°C. The effects of potassium dichromate, hydrochloric acid, and monomer concentrations on the polymerization reaction were investigated. The order of reaction with respect to potassium dichromate, hydrochloric acid, and monomer concentration was found to be 1.011, 0.954, and 1.045, respectively. Also, the effect of temperature on the polymerization rate was studied and the apparent activation energy of the polymerization reaction was found to be 63.658 kJ/mol. The obtained polymer was characterized using XPS, IR, UV-visible, and elemental analysis. The surface morphology of the obtained polymers was characterized by X-ray diffraction and transmission electron microscopy (TEM). The TGA analysis was used to confirm the proposed structure and number of water molecules in each polymeric chain unit. The ac conductivity(σac)of (POPDA) was investigated as a function of frequency and temperature. The ac conductivity was interpreted as a power law of frequency. The frequency exponent (s) was found to be less than unity and decreased with the increase of temperature, which confirms that the correlated barrier hopping model was the dominant charge transport mechanism.

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The chemical graft copolymerization reactions were used to enhance water resistance of paper by reaction of acrylonitrile (AN) monomer onto cellulosic paper sheet in the presence of comonomer (styrene or acrylic acid or itaconic acid) 1 : 1 molar ratio in dimethyl formamide using benzoyl peroxide as free radical initiator under nitrogen atmosphere at 70 C. The infrared spectroscopy confirms that graft copolymerization reaction occurs onto the paper samples. Water absorption test was carried out following the Normal Protocol 7/81 (water absorption by complete immersion) to evaluate the protective effect of the graft treatment onto the paper sheet. It was found that the three graft copolymerization systems reduced the water absorption of the investigated paper and the reduction of water absorption is directly proportional to the grafting %. The wettability of the grafted and ungrafted paper sheet samples were investigated using the wicking time method which exhibits the decreasing of paper sheet wettability using the AN/S comonomers in the graft copolymerization reaction.

Infrared (IR) spectroscopy studies were performed for poly(methyl methacrylate) (PMMA) samples doped with an organic ligand or its cobalt(II) complex after the extraction of the dopant during ␥-radiolysis. There were no drastic changes in the IR absorption band position, but noticeable changes in the intensities were found. The relative transmission of IR absorption bands, such as those at 750, 840, 1065, and 1388 cm Ϫ1 , were measured according to the transmission of the carbonyl group band at 1717 cm Ϫ1. The degradation and recombination mechanism of different groups in the polymeric chain or backbone during radiolysis could be explained by the behavior of the relative transmission data for each group with increasing exposure dose. The tacticity of the PMMA samples was unchanged during radiolysis, and they were found to be syndiotactic. This was confirmed by the IR J values for different PMMA samples before and after irradiation. The protection efficiency of the organic ligand and its cobalt(II) complex was also investigated, and it was found that the organic ligand was more protective than the cobalt(II) complex for PMMA samples against ␥-rays.