Optimization of antibacterial and mechanical properties of an active LDPE/starch/nanoclay nanocomposite film incorporated with date palm seed extract using D-optimal mixture design approach.

A novel active LDPE/TPS nanocomposite films containing date palm seed extracts (Kabkab variety) were developed using D-optimal mixture design. 20 different blends of components including LDPE, TPS, Cloisite 20A, PE-g-MA, EDTA and date palm seed extracts in different proportions were prepared. Using trace and counter plots the effects of each component on the mechanical and antibacterial properties of the composites were studied. The results showed that the films containing a mixture of date seed extract and EDTA had notable antibacterial activity against E. coli and S. aureus; however, these components weakened the mechanical properties of the prepared films. At the same time Cloisite 20A nanoparticles strengthened the films mechanical properties. The optimized formulation for the overall best antibacterial and mechanical properties was 67.5 wt% for LDPE, 4.1 wt% for date seed extract, 2.8 wt% for Cloisite 20A and 2.5 wt% for EDTA. The studied properties of the manufactured film samples were close to the values predicted by the model.