Soy protein isolate nanocomposite film enriched with eugenol, an antimicrobial agent: Interactions and properties

Nanocomposites films were designed from soy protein isolates (SPI), clays (Na+-MMT), and eugenol an antimicrobial agent. Interactions between Na+-MMT and eugenol were evidenced by a shift of the d-spacing by X-ray diffraction analysis. The addition of Na+-MMT (5 and 7.5% w/w) in SPI solution increased its shear thinning behavior and its consistency. Accordingly, a good exfoliation of clays in SPI films was observed. The glass transition temperature of SPI films was impacted by the clays addition but not the water vapor permeability. In contrast, the addition of eugenol in SPI solution did not affected the consistency but induced a decrease of the SPI film Tg and an increase of the water vapor permeability. The presence of eugenol counterbalanced the effect of clays on consistency of film-forming solution. The clay intercalation process was facilitated and the water vapor permeability and active agent release were modified. The presence of clay did not affect the antibacterial effect of eugenol/SPI films. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 135, 45941.