Degradation of hydroxypropyl methylcellulose (HPMC) by acoustic and hydrodynamic cavitation.

The present study aims to investigate the degradation of HPMC on a laboratory scale by acoustic and hydrodynamic cavitation. The effects of temperature and the addition of an external oxidizing agent on the effectiveness of HPMC degradation were systematically investigated by SEC/MALS-RI, FTIR and H NMR. The results of the experiments without cavitation show that an external oxidizing agent alone reduces the weight-average molar mass at 60 °C in 30 min for 45.