Changes in wool protein structure and fabric properties with ultrasonic treatment

Wool fabrics, ultrasonically treated for different time durations, were analysed by Fourier transform infrared (FTIR), differential scanning calorimeter (DSC), and thermo-gravimetric analysis (TGA), in comparison with the wool without ultrasonic treatment. Fabric tensile and thermal properties were measured in addition to the fibre micro structure analysis. Wool protein chains in the macro fibrils were shown to be rearranged to a more regular and less flexible structure, as a result of the ultrasonically treated fabric. Prolonged ultrasonic treatment, however, significantly reduced both fabric tenacity and extensibility. Wool treated with ultrasonics was found to have less mass loss and a higher thermal degradation temperature than that of without ultrasonic treatment and prolonged treated. DSC analysis showed that while ultrasonic treatment has little effect on the fibre crystallinity, an appropriate treatment can provide wool with increased water absorption.