Effect of nanoclay and ethyl-Nα-dodecanoyl-l-arginate hydrochloride (LAE) on physico-mechanical properties of chitosan films

Abstract

Chitosan films have good barrier properties to gases, but present high water vapor permeability.The addition of a nanoclay (Cloisite®30B) was studied to improve the water vapor permeability26 and mechanical properties of chitosan films, and ethyl-Nα-dodecanoyl-L-arginate hydrochloride(LAE) was added as an antimicrobial agent. Chitosan-acetate films were prepared by solvent casting technique from chitosan solutions (20 g/L) with different combinations of nanoclay (0-5-10 g/L) and LAE (0-0.5-1 g/L) by using an experimental design of 32 . Physical properties wereevaluated and the results showed different thickness for all films (0.058-0.084 mm). Moisturecontent (25.2-34.0 g/100g), water solubility (29.0-47.2%), water vapor transmission rate(1.81×10-3-2.34×10-3 kg s-1m-2) and crystallinity decreased significantly in the films with highconcentration of nanocompound, due to clay layers constitute a barrier to gases and water. The elongation at break (49.6-66.3%) and tensile strength (6.7-9.0 MPa) increased significantly. Chitosan film with 10 g/L of nanoclay and/or 1 g/L of LAE gathered the best physico mechanical properties.