Ultrasonic studies of polycarbonate, polysulfone, and polyether sulfone

Abstract Ultrasonic attenuation and velocity measurements are reported for samples of polycarbonate, polyether sulfone, and polysulfone over a temperature range from 10° to 80°C and over a frequency range from 5 to 35 MHz. Observed relaxations are ascribed to short‐range motions of the polymer backbone—here designated the α process. The amplitude of the absorption initially decreased with increasing draw ratio, but after two years returned to the values characteristic of undrawn samples. The longitudinal wave velocity increased with draw ratio in a manner consistent with the creation of molecular order and remained constant over two years. Differences in the attenuation properties between the three polymers studies are discussed in terms of the chemical structure and the macroscopic morphology of the samples.