Acid mediated networked cellulose: Preparation and characterization

High-yield networked cellulose (NC) material was prepared by sulfuric acid dissolution of microcrystalline cellulose (MCC) and regeneration in ethanol. The dissolution was studied by varying treatment temperature and time while acid concentration was kept constant at 70%. Dried NC material was studied using X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD data revealed that the material has mainly an amorphous phase with a crystalline portion characteristic of cellulose II. TEM images confirmed the network nature of the produced material. It was noticed that, when dried, the NC material shrinks in volume while maintaining integrity and shape with an improved hardness upon shrinkage. Hardness and elastic modulus were investigated using nanoindentation and tablet hardness testing. Hardness measured via nanoindentation was 801 Pa with an elastic modulus of 9.9 GPa. (C) 2010 Elsevier Ltd. All rights reserved.