The effect of Nano-emulsion (NE) and Macro-emulsion (ME) of cinnamon essential oil (CEO) on the properties of carboxymethyl cellulose (CMC)-based films was investigated. MEs (diameters of 242–362 nm) and NEs (diameters of 59–80 nm) of CEO were produced through Ultra-Turrax and Ultrasonication, respectively. The scanning electron microscopy (SEM) and atomic force microscopy (AFM) images showed different morphologies in the films containing ME and NE, also a denser and more uniform microstructure was observed in the NE films in comparison with the ME ones. The higher stability of NE in the CMC matrix, increased the thickness of the resulted films. The water vapor permeability (WVP) was increased from 2.59 × 10–9 g/ ms Pa in the control film to 4.43 × 10–9 g/m s Pa in the ME film, and decreased to 1.80 × 10–9 g/ms Pa in the NE film. Adding CEO led to more flexible films with enhanced strain at break (SAB) from 53.56% in the control film to 80% and 94.77% in the ME and NE films, respectively. The antifungal indices against A. niger and M. racemous were 14.16% and 20.82% in the ME films, and were improved to 18.81% and 25% in the NE ones.
