Microwave assisted synthesis of bacterial cellulose-calcium carbonate composites

The effect of microwave irradiation on the calcium carbonate (CaCO3) deposition on bacterial cellulose (BC) membranes was investigated. The experiments were conducted at atmospheric pressure using calcium chloride and sodium carbonate aqueous solutions as starting reactants. The following parameters varied: the exposure time at microwave irradiation and the concentrations of calcium chloride starting solutions. The BC-CaCO3 composites were characterized by means of scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). From the known polymorph of calcium carbonate, calcite and vaterite were deposed on bacterial cellulose membranes in the presence of microwave irradiation doses which were used in this work. Water vapor permeability and pencil scratch hardness were investigated for BC-CaCO3 composites and compared with control samples obtained without microwave irradiation. Significant differences between morphology and even polymorphism of the calcium carbonate crystals were observed for the irradiated samples in comparison with those obtained in the absence of microwave irradiation.