Preparation and Characterization of Films Based on Disintegrated Bacterial Cellulose and Montmorillonite

The food packaging materials from natural polymers including polysaccharides offer an ecologically important alternative to commonly used synthetic, non-biodegradable counterparts. The purpose of this work was to modify of bacterial cellulose (BC) leading to the improvement of its functional properties in terms of use as a food packaging material. Effects of disintegration of BC and addition of montmorillonite (MMT) on its water barrier, mechanical and thermal properties were investigated. Disintegration of BC increased its water vapour permeability (WVP) and thermal stability, but decreased its tensile strength (σ). These changes were closely related to the rearrangement of hydrogen-bond network in the BC structure, resulting in a partial conversion from the Iα to Iβ allomorph. The addition of 2% of MMT did not affect WVP and σ of the disintegrated BC (bBC), while the plasticization of the modified bBC generally decreased WVP, and did not increase σ. The improvement in water barrier properties of bBC modified by adding 2% of MMT in the presence of glycerol was caused by the formation of hydrogen bonds between the components of the composite. The results presented show the potential usefulness of BC modified by disintegration and adding 2% of MMT and 10–15% of glycerol as a food packaging material.