Sustainable Alternatives for Packaging: Exploring the Hygroscopicity of Biodegradable Materials Based on PLA, PBAT, and Rice Husk

This study explores the potential of sustainable materials by combining biodegradable polymers with agro-industrial waste. It aims to offer alternatives to mitigate the adverse environmental impacts of single-use food packaging. The aim is to evaluate the potential of a composite material made from a polylactic acid (PLA)/polybutylene adipate-co-terephthalate (PBAT) blend, reinforced with rice husk (RH), as a viable alternative for food packaging. Two blends containing 10–20 wt% of PBAT (BL1 and BL2) and four composites with 10–20 wt% of RH reinforcement (CO1, CO2, CO3, and CO4) are tested to determine the most suitable formulation in terms of barrier properties. The samples are characterized using Fourier-Transform Infrared Spectroscopy (FTIR), contact angle measurements, Scanning Electron Microscopy (SEM), water absorption, and moisture absorption test. FTIR and SEM analyses reveal partial immiscibility between PLA and PBAT in blends BL1 and BL2. In the SEM analyses, composites CO1 and CO3 (10 wt% RH) exhibit better RH dispersion, resulting in lower water absorption and higher moisture barrier properties. However, the hydrophilic nature of RH indicates the need to improve the interaction at the fiber–matrix interface to optimize performance. Additional studies are ongoing to evaluate additional properties and feasibility for large-scale production, aiming at sustainable industrial applications.