This work evaluated the effect of the combination of nanofillers: organically modified montmorillonite (MMT), sepiolite (SEP) and nano titanium dioxide (TiO2) on the oxygen and water vapor permeability coefficients, light transmission and mechanical properties of poly(butylene adipate‐co‐terephthalate) (PBAT) aiming at packaging application. The clays concentrations were chosen considering percolation threshold from the clays aspect ratio by TEM analyses. Comparing to neat PBAT, oxygen and vapor permeability coefficients showed reduction with the increase of MMT while SEP and nano‐TiO2 did not show significant influence. However, nano‐TiO2 was the only filler able to reduce UV and visible light transmission. Nanofillers and their combinations showed to be statistically significant for the increase in Young's modulus, although the tensile strength and elongation showed no influence. The results were discussed in terms of the fillers' morphology and dispersion. Nielsen's model was applied to estimate the aspect ratio of the MMT in nanocomposites.

This work is an investigation of the effect of different nanofillers: organically modified montmorillonite (MMT), sepiolite (SEP) and nano titanium dioxide (nTiO2) and combination of them in poly(butylene adipate‐co‐terephthalate) (PBAT) films. Thermal morphological and rheological analyses were conducted to explain the behavior of this nanoparticles on O2 and water vapor permeability coefficients, light transmission, and mechanical properties presented in previous study. Thermal stability of the nanocomposites was slightly decreased by the nanofillers presence. Differential scanning calorimetry and X‐ray analyses were carried out to investigate the crystallization behavior of nanocomposites. Transmission electron microscopic analysis showed regular and homogeneous dispersion of the nanoparticles, but scanning electron microscopy showed lack of adhesion in the sepiolite‐PBAT interface. Rheological measurements showed significant increase in both complex viscosity and storage modulus due to interactions between clays and PBAT and the effect of sepiolite and nTiO2 on improving the exfoliation of montmorillonite as synergism between the nanofillers.

The image of Transmission Electron Microscopy Micrographs by Mayara Pollyane Calderaro and colleagues shows the morphology of nanobiocomposites: PBAT/hybrid nanofiller‐montmorilonitte, sepiolite, and nanoTiO2. The nanocomposites with isolated nanoclays present tactoids and some agglomerates, while good dispersion of the nanoTiO2 particle is observed in the polymeric matrix. The hybrid nanocomposites show synergism on mechanical and barrier properties due to the dispersion of nanofillers, mainly for the montmorillonite that presented intercalated and exfoliated structures. Doi: https://doi.org/10.1002/app.50414