Thermal, conductivity, and dielectric properties of poly(2-ethyl-2-oxazoline)-polyvinylpyrrolidone blends

Bio-compatible polymer blends of poly(2-ethyl-2-oxazoline) [PEOX] and polyvinylpyrro-lidone [PVP] were prepared at various compositions (80:20, 60:40, 40:60, and 20:80 wt%). These polymer blends were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The thermal stability of the blends was evaluated by thermogravimetry. The kinetic parameters such as activation enthalpy, Delta H, activation entropy, Delta S, and free energy of activation, Delta G, were calculated using kinetic model given by Broido for all the blends. The thermal studies show that PEOX:PVP (20:80) blend has good thermal stability compared to other blends. The results show that thermal stability and decomposition temperature of PEOX was considerably improved by the addition of PVP. The electrical and dielectric properties of PEOX:PVP (80:20) blend were measured in the temperature range of 313 K - 353 K using an LCR meter for the frequency range 100 Hz - 8 MHz. The dielectric studies shows that dielectric constant, dielectric loss and electric modulus decreases with frequency and increases with temperature, whereas AC conductivity increases with frequency and temperature.