Extending bio-based and biodegradable thermoplastics in food packaging: A focus on multiphase systems

In recent decades, the thermoplastics market has experienced significant growth due to its high global consumption, ability to produce cost-effective goods, and unparalleled properties. However, increasing environmental concerns, reliance on depleting fossil reserves, and sustainability challenges have driven extensive research into bio-based and biodegradable polymers, particularly for food packaging applications. These eco-friendly alternatives offer promising strategies for managing waste and reducing environmental harm. Yet, they face limitations such as poor mechanical and barrier properties, inherent brittleness, and melting temperatures that often exceed their degradation temperatures. This article explores how advancements in multiphase systems, for instance, through methods like plasticization, blending, foaming, and the formation of composites, nanocomposites, and multilayer films, can overcome these drawbacks, enhancing both the functionality and range of applications for these polymers. It discusses how modifying bio-based and biodegradable polymers can produce more processable materials with lower melting temperatures and how blending these polymers with others can create cost-effective, high-performance systems. This review offers a comprehensive exploration of these advanced materials, highlighting their capacity to transform food packaging and promote a more sustainable future.