Effect of shock wave impact on natural chitosan biopolymer

Abstract

In the present study, the influence of shockwave impact on chitosan (CS) material samples is investigated. The shock tube is used to create the shock wave and the experiments are conducted for a shock Mach number of 1.6. CS material sample is exposed to the shock wave by fixing at the driven tube end flange and impacted to 30, 60 and 90 shock impulses. CS material after the impact was characterized for its structural changes by the Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and viscometer results. The FT-IR results of the treated sample indicate that the bond length is reduced as the functionality of amide increases by lowering the mass of the samples. Significant changes are observed for the CS samples exposed to 90 shock pulses. The degree of deacetylation is increased from 75% to 89%. XRD results indicate that the crystallite size is enhanced by 109% in the treated samples and significant morphological changes are noticed in the SEM images. The viscosity is decreased to 88% and the reduction in molecular weight by 92% indicates the shock-treated CS samples contain high water solubility. Results emphasized that the shock tube technique yields quick findings with favorable changes in the CS depolymerization reaction and demonstrated that it is an efficient, cost-effective and less time-consuming approach.