Fish gelatin-nanoclay films. Part I: Effect of a kind of nanoclays and glycerol concentration on mechanical and water barrier properties of nanocomposites

摘要

The aim of work was the improvement of the mechanical and water barrier properties of nanocomposites prepared from fish gelatin and nanoclays (5-15%), plasticized with glycerol at different concentrations. The effect of hydrophilic Cloisite Na~+ and Nanomer®PGV was compared with that exerted by organically modified more hydrophobic Nanofil®2 and NanoBent ZR-1. Antimicrobial activity of nanocomposites containing hydrophobic nanoclays was also investigated. In a nanocomposite with 5% Cloisite Na~+ and 15% glycerol, the Tensile strength (TS) was by 20% higher than that for plasticized films without nanoclay. The improvement of TS was also evidenced for plasticized nanocomposites containing 5% of hydrophobic NanoBent ZR-1 and Nanofil®2. Nanocomposites containing 5% of Cloisite Na~+ with 15% glycerol, and these containing 5% Nanofil ®2 or NanoBent ZR-1 with 20% glycerol, showed 23% and about 15%, respectively, lower water vapor permeability than gelatin films. Gelatin-NanoBent ZR-1 nanocomposite caused complete inactivation of gram-positive bacteria S. aureus and L. innocua.