Preparation and characterization of polyvinyl alcohol/chitosan blends plasticized and compatibilized by glycerol/polyethylene glycol

The synergistic plasticization/compatibilization effect of poly(ethylene glycol)/glycerol is reported for poly(vinyl alcohol) (PVA)/chitosan blends. The optimum concentration of PEG was first determined by preparation and characterization of PVA/PEG blends at different ratios (9:1, 6:1 and 3:1). The PVA/chitosan blends, plasticized with PEG, glycerol, and their combination, were also prepared and characterized. Fourier transform infrared results suggested that PEG enhances the compatibility of PVA/chitosan blends. This claim was further confirmed by the morphological results. However, PEG had a detrimental effect on the crystallinity of PVA/chitosan blends. The combination of glycerol and PEG caused a five-time enhancement in the elongation at break values as compared with the blend plasticized with glycerol. The antibacterial properties against E. coli were also evaluated. All in all, the high antibacterial properties of the blend films along with good mechanical and morphological properties could be beneficial in wound dressing and food packaging applications which need further investigation.