Starch-based nanocomposites: A comparative performance study of cellulose whiskers and starch nanoparticles

A comparative performance study of cellulose whiskers (CW) and starch nanoparticles (SN) on plasticized starch (PS) reinforcement has been presented. In order to study the involved surface phenomena, CW and SN were extracted through acid hydrolysis using sulfuric acid to fulfill the similar surface groups and interactions. CW-filled and SN-filled nanocomposites were then prepared with relatively identical process to alleviate the effect of fabrication method for better comparison of CW and SN performance on PS reinforcement. Morphology of nanoparticles and their dispersion state in the corresponding nanocomposites were investigated by transmission electron microscopy and field emission scanning electron microscopy, respectively. X-ray diffraction was used for crystallography of nanocomposites and established the transcrystallization only in CW-filled nanocomposites. Nanocomposites comprising quasi-spherical SNs showed higher reinforcement in dynamic mechanical tests compared to the corresponding nanocomposites containing rod-like CWs, which were attributed to more efficient filler/filler and filler/matrix interactions originated from hydrogen bonding in SN-filled nanocomposites.