Investigation of Mechanical Properties, Antibacterial Features, and Water Vapor Permeability of Polyvinyl Alcohol Thin Films Reinforced by Glutaraldehyde and Multiwalled Carbon Nanotube

Polyvinyl alcohol (PVA) thin films were reinforced by glutaraldehyde and multiwalled carbon nanotubes (MWCNTs) and then mechanical, water solubility, water swelling, water uptake, water vapor permeability, and antibacterial properties of the films were examined. Cross-linking by glutaraldehyde or incorporation of MWCNT caused a significant increase in tensile strength, decrease in elongation at break, and increase in Young's modulus of the PVA films, while MWCNTs were more effective rather than that of glutaraldehyde. Cross-linking by glutaraldehyde or incorporation of MWCNT caused a significant decrease in water solubility, water swelling and water uptake, with a similar manner. Cross-linking by glutaraldehyde or incorporation of MWCNT caused a significant increase in the light absorbance, while maximum absorbance was at 400 nm. Only PVA/MWCNT films but no PVA/glutaraldehyde showed significant antibacterial activities in a dose-dependent manner against both Gram-positive and Gram-negative bacteria. Thus, noncovalent improvement by MWCNT was more effective on the PVA thin films rather than covalent cross-linking by glutaraldehyde. Our results suggest that the PVA/MWCNT composites films could be used as a very attractive alternative to traditional materials for different biomedical and food applications. (C) 2013 Society of Plastics Engineers