Ultrasonic study of PVA and PVA / PAAM film composites prepared by casting method

摘要

The PVA/PAAM composite membranes of poly vinyl alcohol and Polyacrylamide were prepared by casting method, the appropriate weights of PVA were variable (0.25, 0.5, 0.75, 1 and 1.25 gm) dissolved in (25ml) of distilled water under stirring and heat (70?C) for (30 min.) then different weights (0.15 and 0.3 gm.) of PAAM were added to each PVA . In order to evaluate the mechanical properties of PVA and PVA/ PAAM composite the ultrasonic measurements were performed at the samples. These properties are velocity of ultrasonic waves, absorption coefficient of ultrasonic waves, relaxation amplitude, specific acoustic impedance, bulk modules and compressibility. The results show that all these properties are increasing with the increase of the polymer thickness except compressibility is decreasing with increase the thickness; results also show that when adding PAAM these properties have higher values than those before increasing except compressibility is decreasing. Results also show that adding PAAM polymer to PVA enhances these properties as a result of high values after addition.