Biodegradable polymers and composites: Recent development and challenges

Biodegradable polymers are highly sought after as they have the potential to reduce the issue of plastic waste and eventually lead to a circular economy. Yet, conciliating eco‐friendliness with competitive properties is often challenging. Polymerization and processing techniques have been developed and optimized to improve such factors. Some of the common polymerization methods to obtain such materials are condensation, ring‐opening, addition, and biocatalytic‐assisted polymerization. Alongside that, processing techniques such as melt mixing/extrusion, solution castings, compression, and injection molding have also been employed for the manufacture of biodegradable polymers. While these traditional techniques are viable routes to market, there is still the need to further improve their properties to make them comparable to their petrochemical‐based counterparts. To assist with that, the production of composites and blending techniques are facile approaches that demonstrated promising improvements in their properties. Based on these aspects, this review is aimed at discussing the main types of biodegradable polymers, followed by the compositing approaches reported in the recent literature, their structure–property relationships, and biodegradability mechanisms. The first section provides an introductory overview of biodegradable polymers and their composites. The second section focuses on the most prominent polymers used in the industry. Furthermore, the fabrication techniques, along with their property and application relationships are provided with an emphasis on mechanical reinforcements and the biomedical field. Finally, some future perspectives are given to clarify some of the known challenges and, possibly, provide some insights for the reader to develop novel ideas.