الفهرس 
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Abstract
This work reports on the synthesis of silver and gold nanoparticles
embedded within PVA matrix to provide new materials that displayed
enhanced catalytic properties. Versatile and robust approaches to the
synthesis of PVA/Ag and PVA/Au have been developed.
PVA/Ag nanocomposites were fabricated using gamma-irradiation.
The irradiated samples are compared with unirradiated ones to investigate
the mechanism of silver nanoparticle formation and the effect of gamma
irradiation and AgNO3 on the size of the particles. The metal centers of a
metallopolymer were used as the seed point for size controlled
nanoparticles growth. By growing the nanoparticles directly in the
backbone of the PVA polymer, use of surfactants, solvents and reductant
of metallic ions is eliminated which allows for direct interaction between
the two materials. The particle size increased when the silver salt
concentration was increased.
The integration of highly monodispersed gold (Au) nanoparticles
into polyvinyl alcohol (PVA) film is developed through a new seededgrowth
pathway. Silver (Ag) nanoparticles are used during the synthesis
as the reactive seeds to induce the reduction of Au under the UVirradiation.
The narrow surface plasmon resonance confirms the success
of preparing gold nanoparticles with narrow size and shape distribution.
The as-prepared PVA/Au nanocomposite films show sturdy cohesion
between the PVA chains and/or between PVA network and gold
nanoparticles. This has led to interest in their use as brand-new product in
catalytic reduction of 4-nitrophenol with NaBH4. The catalytic activity of
the prepared nanocomposites on the reduction of some organic pollutants
was examined. The samples were analyzed using UV–Visible
spectroscopy, X-ray diffraction; Transmission Electron Microscopy and
Fourier transform infrared spectrometry.