Relaxation dynamics and a.c. conductivity in poly (vinyl lcohol)/hydroxypropyl cellulose

The frequency-dependent dielectric properties (dielectric permittivity, dielectric loss factor and a.c. electrical conductivity) of blends of poly(vinyl alcohol)/hydroxypropyl cellulose (PVA/HPC) prepared by the solution-cast technique is investigated in the frequency ranges from 1 to 100 kHz to examine a wide range of molecular mobility of the amorphous phase of the blend systems. The dielectric properties on certain chosen blends before and after irradiation with different fast neutron fluencies in the range from 105 to 108 n/cm2 are also studied. The obtained results noticed that, measureable changes in the behavior and values of the dielectric properties under investigation are detected. These changes may be attributed to degradation and/or cross-linking process either by the presence of HPC with different concentrations or by the irradiation with different fast neutron fluencies or both of them, which suggests that the observed dispersion depends on composition and irradiation of blend matrix.