ABSTRACT
All-cellulose composites (ACC) represent a relatively new class of self-reinforced bio-composites that are entirely based on cellulosic materials. During synthesis of ACC, the cellulosic materials are commonly dissolved in a solvent in the presence of some undissolved cellulosic reinforcement; thereby, after regeneration of dissolved cellulose, it acts as matrix phase. The matrix phase in ACC is isotropic and the reinforcement may be isotropic or anisotropic in nature. ACC can be prepared through dissolution and regeneration of non-derivatized cellulose or through melting of derivatized cellulose. Regeneration is a step in which dissolved cellulose get transformed to solid cellulose in contact with a non-solvent or coagulant medium. During regeneration, due to hydrophilic nature of cellulose, it swells and after drying creates internal voids in the fiber–matrix interface of ACCs. Wide-angle X-ray diffraction analysis is the most useful tool for characterizing the phase of cellulose before and after preparation of ACCs as well as for observing changes in crystallinity, crystal size, and orientation.
