Some of physical properties of polyvinyl alcohol dissolves in distilled water had been studied at
different concentration (0.25%, 0.5%, 0.75%, 1.0%, and 1.25%) before and after adding 1gm from
NH4Cl for all concentrations, the Rheological properties such as shear viscosity, relative viscosity and
reduced viscosity are measured and after that the ultrasonic velocity had been measured by ultrasonic
waves system at frequency 40 KHz, other mechanical properties had been calculated such as absorption
coefficient of ultrasonic waves, relaxation time, relaxation amplitude, specific acoustic impedance,
compressibility and bulk modules. Another acoustic mechanical properties were measured and
calculated at a same time such as the ultrasonic wave amplitude before and after absorption by solution
were showed on oscilloscope ,then we calculated absorption coefficient. The results show that all these
properties are increasing with the increase of the polymer concentration except velocity is decreasing
with increase the concentration; results also show that when adding NH4Cl these properties are
increasing.