Bio-based films/nanopapers of banana tree pseudostem: From lignocellulosic wastes to added-value micro/nanomaterials

Abstract

The growing demand for products with lower environmental impact and the extensive applicability of cellulose nanofibrils (CNFs) have received attention in several fields of knowledge due to their attractive properties. In this study, bio-based films/nanopapers were produced with CNFs from banana tree pseudostem (BTPT) wastes and Eucalyptus kraft cellulose (EKC) and were evaluated by their properties, such as mechanical strength, biodegradability and light transmittance. The CNFs were produced by mechanical fibrillation (after 20 and 40 passages) from suspensions of BTPT (alkaline pre-treated) and EKC. Films/nanopapers were produced by casting from both suspensions with concentrations of 2% (based in dry mass of CNF). The BTPT films/nanopapers showed greater mechanical properties, with Young’s modulus and tensile strength around 2.42 GPa and 51 MPa (after 40 passages), respectively. On the other hand, the EKC samples showed lower disintegration in water after 24 h and biodegradability. The increase in the number of fibrillation cycles produced more transparent films/nanopapers and caused a significant reduction of water absorption for both raw materials. The permeability was similar for the films/nanopapers from BTPT and EKC. This study indicated that attractive mechanical properties and biodegradability could be achieved by bio-based nanomaterials, with potential for being applied as emulsifying agents and special membranes, enabling more efficient utilization of agricultural wastes.

Recovery of Banana Waste-Loss from Production and Processing: A Contribution to a Circular Economy

“…It is possible to find cellulose nanofibrils (CNF) to produce biobased materials. Among its properties are crystallinity, high capacity to form films/nano papers with low thermal expansion, high optical transparency, tensile strength, Young's modulus and barrier (to oil, oxygen and water vapor), in addition to abundancy and non-toxicity [154].…”