Development of Ionic Liquid-Mediated Antibacterial Cellulose-Chitosan Films

The solubility of cellulose, chitosan and their composites has been investigated to understand their roles in the formulation of antibacterial cellulose-chitosan composite films and their contributions to the performance of the films. Antibacterial and homogeneous cellulose-chitosan composite films with high mechanical property were successfully prepared by co-dissolving cellulose and chitosan in 1-ethyl-3-methylimidazolium acetate (EmimAc) ionic liquid. The composite films were further characterized by using XRD, TGA, FTIR, SEM, mechanical strength and antibacterial ability measurements. XRD analysis of the films suggested that the structure of crystalline as well as crystallinities of both polymers changed during the processes of dissolution and regeneration, although their solubility varies considerably. The developed films were thermally more stable than the regenerated cellulose or chitosan itself. Hydrogen bonding between cellulose and chitosan in the blend films was determined by FTIR. SEM images also revealed a homogeneous and compact structure of the blend films. In addition, cellulose-chitosan composite films showed highly inhibitory effects on the bacteria of E. coli. and S. aureus.