Biohybrid barrier films from fluidized pectin and nanoclay

The work was aimed at studying the effects of nanosized montmorillonite on the barrier properties of the unmodified sugar beet pectin films as a function of relative humidity. 0.5, 1 or 2 wt% nanoclay was dispersed in an aqueous 5 wt% pectin solution using high pressure fluidizer. Nanoclay-pectin hybrid film formation and high shear induced orientation of nanoclay platelets were investigated by means of model surfaces which were prepared using high shear spincoating. After fluidization, the nanoclay formed uniform and laterally oriented stacks consisting of approximately 15 individual nanoclay layers. Pectin films with the final nanoclay concentrations of 0, 10, 20 and 30 wt% were prepared by casting. Nanocomposite films made of pectin and montmorillonite showed improved barrier properties against oxygen, and water vapour. Films were also totally impermeable to grease. The developed biohybrid material can be potentially exploited as a safe and environmentally sound alternative for synthetic barrier packaging materials.