Preparation of chitosan-PE antimicrobial bi-layer films and antibacterial activity

Chitosan-PE films were prepared by combining the excellent film property and antimicrobial activity of chitosan with good mechanical and barrier properties of PE film. The effect of the concentration of chitosan,acetic acid,glycerol(Gly) and Span 40 on tensile strength(TS) and elongation at break(E) were investigated.The optimum combine ingredients were obtained through single factor experiments and Box-Behnken Design,which were 0.94% chitosan,0.49% acetic acid,1.07% Gly and 1.41% Span 40. TS and E of chitosan-PE bi-layer films were 3.59MPa and 116.72%,respectively. Also,the antibacterial activity against E. Coli and B. Subtilis of the film were measured. Results showed that the antibacterial ratio was 80.77% and 93.02%,respectivedly.