Valorization of Agro-waste in Bio-based and Biodegradable Polymer Composites: A Comprehensive Review with Emphasis on Europe Perspective

Bio-based and biodegradable polymer composites hold great potential as sustainable alternatives to traditional plastics, helping to address the growing issue of plastic waste accumulation. The use of agro-waste in their production adds value to this alternative, offering a promising example of a circular economy and waste valorization. Previous studies on agro-waste utilization in biocomposites have mainly focused on well-known natural fibers, often overlooking a wider variety of reinforcement options and the significance of local resource availability. This review addresses these gaps by examining agro-waste sources available in Europe and, through bibliometric analysis, evaluating their potential as biopolymer and natural reinforcement components in biocomposites. It provides an in-depth analysis of the composition and properties altered in biocomposites by a wider spectrum of agro-waste reinforcements, including particulate materials. The findings suggest that wheat straw holds significant potential for biocomposite production in Europe, given its availability and the volume of existing research. Additionally, particulate materials such as fruit peels (orange, grape), nutshells (walnut), coffee silverskin, and powders (soy flour, wheat bran), as well as agro-waste ashes, show promise as alternative reinforcement sources, warranting further investigation. The review also explores the latest findings on novel strategies to improve the performance of agro-waste-derived biocomposites, while addressing production challenges, economic feasibility, and regulatory constraints. In conclusion, agro-waste represents a valuable resource for sustainable material production in the form of biocomposites. Advancing research on local agricultural waste could unlock significant opportunities for biocomposite development and drive progress in sustainable materials.