Ultrasonic depolymerization of aqueous polyvinyl alcohol.

摘要: Ultrasonication has proved to be a highly advantageous method for depolymerizing macromolecules because it reduces their molecular weight simply by splitting the most susceptible chemical bond without causing any changes in nature of polymer. Most effects involved controlling can attributed large shear gradients and shock waves generated around collapsing cavitation bubbles. In general, polymer degradation process become acceptable industry, is necessary able specify sonication conditions which lead particular relative molar mass distribution. This necessitates identification appropriate irradiation power, temperature, concentration time. According results this study reactors constructed worked well depolymerization was possible degrade aqueous polyvinyl alcohol (PVA) with ultrasound. The extensive took place at lowest frequency used study, i.e. 23 kHz, when input power above threshold test PVA, 1% (w/w). Thus confirms general assumption that forces rapid motion solvent following cavitational collapse are responsible breakage bonds within effect interpreted terms increase viscosity concentration, molecules less mobile solution velocity bubbles therefore smaller.