Dissipative Processes in a Polyvinyl Alcohol–Silver Nanocomposite System

Films are prepared from an aqueous solution of polyvinyl alcohol (PVA) and silver nitrate AgNO₃ under ultraviolet irradiation (UV). The effect the filler has on their physicochemical and relaxation properties is studied via relaxation spectrometry. The resulting spectra are characterized by two local temperature peaks of dissipative losses, regardless of the state of silver in the PVA structure. With PVA–Ag⁺ chelates, the intensity of the peak responsible for vibrations of OH-groups falls and is partially restored after irradiating samples with UV light. Shear modulus G(T) for the original PVA matrix is higher than the one for the filled system (PVA–AgNO₃). The temperature of the glass transition in the region where the α peak appears is reduced in filled systems.