Physical, structural and antimicrobial properties of poly vinyl alcohol–chitosan biodegradable films

Chitosan (CH) was blended with poly vinyl alcohol (PVA) in different compositions to obtain biodegradable films (PVA90:CH10, PVA80:CH20, PVA70:CH30). Blends and neat polymer films (PVA100, CH100) were characterized for their thermal behavior, structural, mechanical and barrier properties as well as antimicrobial activity. Both polymers showed good compatibility, as demonstrated by FESEM images and thermal behavior. A reduction in crystallinity of the blend was observed as the chitosan content was increased. Moreover, chitosan addition strongly reduced the film stretchability while increased the film rigidity and resistance to fracture, mainly at 70:30 PVA:CH ratio. Additional advantages of chitosan incorporation to PVA films are the reduction of the UV-transmittance while providing antimicrobial properties.