Effect of milling time on the microstructure and dielectric properties of chitosan nanopowder

The effect of milling time on the microstructure of chitosan nanopowder had been investigated. This study fabricated chitosan nanopowder via ball milling at different milling time. The milling time used were 0, 60, 180 and 360 minutes, indicated by CHO, CH60, CH180 and CH360, respectively. From the SEM results, the milling time not only resulted in the homogenous dispersion but also the reduction of particle clustering and the reduction of distances between the particles. The optimal grain and crystallite size of CH180 is 8.5 nm and 20.1 nm, respectively. The chitosan nanopowder showed that the milling time does affect the crystallite size. The average crystallite size of chitosan nanopowder is 20 nm. The dielectric constant and loss values decrease with the frequency and increase with the milling time. Thus, the effect of milling time on microstructures and dielectric properties of chitosan nanopowder could increase the internal structure of the granules and applied to synthesis the solid electrolyte.