Starch Nanocomposites

In the recent years, because of availability, renewability, low density, high reinforcement properties, and environmental concerns, the use of cellulose nanofibers was increased. Extraction of cellulose nanofibrils (microfibrilated cellulose (MFC)) from plants cell wall has been done by different methods which almost all of these methods include a chemical purification of cellulosic fibers and a mechanical treatment for disintegration of cell wall. In this work, a chemi – mechanical method was developed and used to extract MFCs from rice straw. In acid hydrolysis steps, concentration of acid and treatment time was optimized by design of experiment (DOE) to achieve high total crystallinity index. The dimension of achieved nanofibers was investigated by SEM and optical density method. Also, chemical composition of nanofibers was determined by NREL. In second part, a composite was prepared by cellulose nanofibers and thermoplastic starch. Afterward, the effect of nanofibers on mechanical and barrier properties of TPS film were investigated.

Key word: rice straw, nano fiber, starch,composites