Synthesis of cellulose-calcium silicate nanocomposites in ethanol/water mixed solvents and their characterization

Cellulose-calcium silicate nanocomposites with calcium silicate nanoparticles homogeneously dispersed in the cellulose matrix have been successfully synthesized using cellulose solution, Ca(NO3)(2)center dot 4H(2)O and Na2SiO3 center dot 9H(2)O in ethanol/water mixed solvents at room temperature for 24 h. The cellulose solution was previously prepared by the dissolution of cellulose in a solvent system of N,N-dimethylacetamide (DMAc)/lithium chloride (LiCl). The feeding order had an influence on the morphology of the cellulose-calcium silicate nanocomposites and the size of the calcium silicate particles. The cellulose in nanocomposites showed cellulose type II crystalline structure. The products were characterized by X-ray powder diffraction (XRD), thermogravimetric analysis (TG), differential scanning calorimetric analysis (DSC), Fourier transform infrared spectrometry (FT-IR), energy-dispersive X-ray spectra (EDS), and scanning electron microscopy (SEM). (C) 2009 Elsevier Ltd. All rights reserved.