超音波による溶融ポリマー中の微細粒子モデル凝集体の分散挙動 Ultrasonic Mixing : Visualization of Agglomerate Dispersion in Polymer Melts
Here we present a basic study of agglomerate dispersion in polymer melts under ultrasonic field. For this study, we visualized dispersion behavior of the model agglomerate. An ultrasonic device featuring glass windows was developed and attached to a twin screw extruder. In this device, a horn vibrates longitudinally at a frequency of 19kHz with amplitude of 7μm, inducing a dynamic pressure field in the polymer melt. Titanium dioxide (TiO<sub>2</sub>, d=220nm) was used as a filler. Polystyrene (PS) and polycarbonate (PC) were used as the matrix polymers. Two types of model agglomerate were prepared: loose agglomerate and compressed agglomerate. The agglomerate were successfully destroyed and highly dispersed in the matrix polymers under the ultrasonic field. The agglomerate increased the diameter, repeating an intense "expansion-contraction" motion at the same frequency as the ultrasonic wave. It is presumed that the dynamic pressure field in polymer melts due to ultrasonic waves, causing intense motion and destroying the agglomerate structure within one second.
成形加工 18(11), 807-812, 2006-11-20
The Japan Society of Polymer Processing