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Novel bionanocomposite films of chitosan/montmorillonite (CS/MMT) activated with ginger essential oil (GEO) were produced and characterized in terms of their physical and morphological properties. The homogenization process led to a good interaction between the chitosan and the nanoparticles, however the exfoliation was diminished when GEO was incorporated. Film glass transition temperature did not statistically change with the incorporation of either MMT or GEO, however the value was slightly reduced, representing a relaxation in the polymer chain which corroborated with the mechanical and barrier properties results. Pristine chitosan films showed excellent barrier properties to oxygen with a permeability of 0.184 × 10−16 mol/m·s·Pa being reduced to half (0.098 × 10−16 mol/m·s·Pa) when MMT was incorporated. Although the incorporation of GEO increased the permeability values to 0.325 × 10−16 mol/m·s·Pa when 2% of GEO was integrated, this increment was smaller with both MMT and GEO (0.285 × 10−16 mol/m·s·Pa). Bionanocomposites also increased the UV light barrier. Thus, the produced bioplastics demonstrated their ability to retard oxidative processes due to their good barrier properties, corroborating previous results that have shown their potential in the preservation of foods with high unsaturated fat content.

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The glass transition and crystallization kinetics of a glass with a molar composition 60BaO-30B 2 O 3-10SiO 2 were investigated by differential scanning calorimetry (DSC) under non-isothermal conditions. DSC curves exhibited an endothermic peak associated with the glass transition and two partially overlapped exothermic peaks associated with the crystallization of the glass. The dependence of the glass transition temperature (T g) and of the maximum crystallization temperature (T p) on the heating rate was used to determine the activation energy associated with the glass transition (E g), the activation energy for crystallization (E c), and the Avrami exponent (n). X-ray diffraction (XRD) revealed that barium borate (b-BaB 2 O 4) was the first crystalline phase to be formed followed by the formation of barium silicate (Ba 5 Si 8 O 21). The variations of activation energy for crystallization and of Avrami exponent with the fraction of crystallization (v) were also examined. When the crystallization fraction (v) increased from 0.1 to 0.9, the value of local activation energy (E c (v)) decreased from 554 to 458 kJ/mol for the first exothermic peak and from 1104 to 831 kJ/mol for the second exothermic peak. The value determined for the Avrami exponent was near 2 indicating a similar one-dimensional crystallization mechanism for both crystalline phases. This was confirmed by the morphological studies performed by scanning electron microscopy (SEM) on glass samples heat-treated at the first and at the second crystallization temperatures. V