Innovative solutions and challenges to increase the use of Poly(3-hydroxybutyrate) in food packaging and disposables

Poly(3-hydroxybutyrate) (PHB) has gain in recent years a huge interest in the food packaging field due to its renewable origin from waste as well as non-food crops, high mechanical strength, medium-to-high barrier performance, and inherent biodegradability in natural environments. Despite these advantages, PHB also shows a narrow processing window and high brittleness since this homopolyester shows low thermal stability and high crystallinity, limiting its industrial application. The present review provides an updated state of the art of the most relevant aspects in terms of processing and properties of PHB materials with a particular emphasis for their use in sustainable food packaging. It also describes the most potential strategies that can be applied to improve both the processability and mechanical properties of PHB, including the melt blending with green plasticizers and flexible biodegradable polymers as well as the development of more ductile co-polyesters. Finally, the waste management of the newly developed PHB-based articles is discussed, from their potential compostability to develop more biopolymers to more economically favored alternatives such as mechanical and chemical recycling technologies.