Voltage Effect in Holograms of Polyvinyl Alcohol with FeCl3

Abstract

Abstract:We show experimentally that the metallic salt, FeCl 3 , at different concentrations, provides photosensitivity and conductivity characteristics with poly(vinyl alcohol) material. The holographic recording in this photosensitive material was made in real time.The effect of applied voltage on holographic diffraction gratings in the recording process and the changes in their diffraction efficiency, depending on their composition, are shown. In addition, we describe the photo-mechanism, physicochemical processes, and water condensations involved in changes of the formation of images due to applied voltage. The results suggest that polymers doped with metallic salts may have potential as inexpensive photosensitive materials that are easy to work under normal laboratory condition.

Ferrocene/ferrocenium redox shuttling: Peroxide decomposition catalysis applied to vinyl monomers polymerization under suspension conditions

“…However, the amount of iron in the overall polymerization process must be considered carefully for several reasons: i) iron derivatives are known to affect the quality of the polymer if present in high concentration, e.g. in an amount equal or close to that of the peroxide, which may facilitate the oxidation process during the lifetime of the polymer, thus contributing to reduce its thermal stability [16,17]; ii) iron can also accelerate the termination of radical polymerization when present in its higher oxidation state [18] and iii) iron can interfere with the presence of surfactant in emulsion or suspension polymerization, typically polyvinyl alcohol (PVA), which is necessary to stabilize the medium and obtain polymer particles with the required size and appropriate properties, for example through ionic-dipole interactions between iron and hydroxyl groups (-OH) in polymeric chains of PVA [19][20][21]. The surfactant properties of the latter would be weakened, leading to a disruption of the polymerization medium and damaging the physical properties of the final polymer.…”