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The non-cross-linked and cross-linked polyvinyl alcohol (PVA) films were prepared by the casting method then irradiated with gamma rays for various doses up to 300 kGy. The structure and characterization of PVA were determined by using Infrared spectroscopy (FTIR), ultraviolet spectroscopy (UV) and X-ray diffraction (XRD). Swelling behaviour was also investigated. Mechanical properties have been examined with respect to the absorbed dose. The color of the films changed to yellowish-white after irradiation and the crystallinity of the films decreased with increasing dose. Additional changes observed by FTIR analysis of the degradation products demonstrated that the radiolysis of PVA was initiated by liberation of H and OH groups leading to scission of the main chains and formation of carbonyl and double bond groups. Thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) were performed. The FTIR, UV, XRD and mechanical properties indicate that the addition of cross-linker led to high degrees of interaction between the cross-linker and the macromolecules of polymeric chains and acted as a stabilizing agent against gamma irradiation. [ABSTRACT FROM AUTHOR]

A new polymer containing cyano groups was synthesized by ?-irradiation. The amidoximated polymer was prepared using hydroxylamine hydrochloride in basic medium. The characterization of monomer, polymer and amidoximation was confirmed by IR and NMR spectroscopy. The complex formation of the amidoxime salt towards Ag I , Cu II and Ag I /Cu II mixture in aqueous solution was studied by AAS, EDS, and ESR spectrometry. The binding capacity of these metal ions is selective in favor of silver(I) ion. The thermal stability of polymers and their complexes was investigated using TG analysis. The change in their morphology was observed by SEM. Potential biological activity of the polymer and its complexes towards some types of bacteria and fungi was tested under the same conditions. Silver (I) complexed polymer had a strong biocidal activity for all tested bacteria and fungi. [ABSTRACT FROM AUTHOR]

Appropriate eye and skin protection is a prerequisite for the safe operation of He-Ne laser in industrial and laboratory environments. This article reports on the measurement of the optical parameters of Poly(tetrafluoroethylene-perfluorovinyl ether) grafted by acrylic acid and complexed with Cu(II) when exposed to He-Ne laser beam of wavelength of 632.8 nm and power 12.5 mW. Transmittance, reflectance, and refractive index spectra are presented. The study showed that the material has a protective level 4. Environmental conditions like thermal and fading processes were tested. This suggested that the material preserves its protective features as a protective eye and skin barrier of protective level L4. This was applied for an occupational working time up to 8 h, temperature up to 50°C, and for a time of 74 days after laser irradiation. [ABSTRACT FROM AUTHOR]