Temperature dependent ultrasonic and conductivity studies in aqueous polymeric solution

Sound velocities, viscosity and density of aqueous solution of PEG of average molecular weight of 4000 g/mole have been measured as a function of temperature in the range 308–338 K at different frequencies. Isentropic compressibility, ultrasonic attenuation and acoustic impedance have been derived from the data. From velocity measurements it has been found that velocity changes near melting temperature due to change in the lattice of polymer. Changes in polymer lattice can also be monitored by complex impedance spectroscopy hence, real and imaginary part of the impedance of mixture of PEG with water were measured in the frequency range 40 Hz to 100 kHz in the same temperature range. From these data bulk electrical conductivity has been calculated. The results have been discussed in terms of molecular interaction occuring in the solution.