Nanofibrillated pulps from Amazonian species as a potential raw material for ecological packaging

Abstract

Using cellulosic micro/nanofibrils (MFC/NFC) in developing films for coatings and packaging has aroused industrial interest to replace plastic. This study proposes functionalizing packaging films composed of hybrid suspensions of 80 % titica vine (Heteropsis flexuosa) and 20 % Pinus to improve their mechanical properties. The MFC/NFC were produced by mechanical fibrillation and adding proportions of 1, 2.5, and 5 % of nanolignin, vegetal tannin, and synthetic termite saliva. Both suspensions had concentrations of 1 % (w/w). The MFC/NFC were evaluated for energy consumption, microstructural, and stability, while the films were for physical, optical, barrier, and mechanical properties. Films with nanolignin 2.5 % obtained lower WVP and degradation in water, with greater hydrophobicity and puncture strength. The treatment with tannin 1 % obtained higher density and lower porosity, while termite saliva 1 % presented higher tensile strength at around 53.1 MPa. The additives improved the quality index of the MFC/NFC (>51.1 points). It is concluded that adding different binders can help expand the use of MFC/NFC. New studies are essential to seek pre-treatments or alternative fibrillation methods to increase their application and efficiency for fiber cell wall fibrillation, in addition to the need for a deeper analytical understanding of the interactions of additives with cellulose.