Ultrasonically synthesized organic liquid-filled chitosan microcapsules: Part 1: Tuning physical & functional properties

Abstract

This study reports the synthesis of tetradecane-filled chitosan microcapsules in acetic acid aqueous solutions using high intensity ultrasound at 20 kHz. The size, size distribution, and stability of microcapsules were tuned by varying the concentration of acetic acid from 0.2% to 25% v/v. After long-time storage at room temperature (more than 3 months), the microcapsules maintained their shell-core structure where the volume of the microcapsules at 0.2% acetic acid concentration increased by 8.3% due to leaking and coalescence. Microcapsules were consistently spherical and had a smooth shell surface, however, their shell thickness varied with acetic acid concentration. The relaxation behavi..