Effects of nanosilica and nanocellulose on poly(butylene adipate‐<i>co</i>‐terephthalate) nanocomposites for food packaging applications

Abstract Polymeric materials are highlighted in the global market due to their low cost, excellent properties, and diversity of applications, such as food packaging, which in addition to protecting packaged foods also promotes control and conservation against contaminants. Thus, the objective of this research is to investigate the effects of adding silica nanoparticles and cellulose nanofibers, alone and together, on the properties of poly(butylene adipate‐ co ‐terephthalate), aiming for application in food packaging. For this purpose, PBAT and the nanofillers were initially mixed in a rheometer to produce masterbatches, and, then, to be processed by a single screw extruder to generate the nanocomposites. The nanocomposites are analyzed by scanning electron microscopy, x‐ray diffraction, thermogravimetric analysis, differential scanning calorimetry, nuclear magnetic resonance, tensile testing, water contact angle, and microbial permeability. In low concentrations, it is observed that the system tends to be less heterogeneous. Nanoparticles do not interfere with thermal stability and present a barrier to microorganisms. Interestingly, in the two conditions studied, polymers with cellulose nanofibers or silica nanoparticles have filtering capacity, being effective as physical barriers to the growth of microorganisms within 60 days. However, the effect on mechanical properties is small, being more pronounced with the use of cellulose nanofibers.