Poly(butylene succinate) (PBS): materials, processing, and industrial applications

The development of biodegradable and compostable materials as alternative to fossil-based plastics is today of paramount importance. Polybutylene succinate (PBS) is a class of biodegradable aliphatic polyester that can be achieved from succinic acid and 1,4 butanediol, which is of broad scientific and industrial interest among other biodegradable polyesters due to its compostability according to ISO EN13432 standard. PBS is considered one of the most interesting compostable polymers because of the good compromise of mechanical endurance, ductility, toughness and impact resistance. It is also characterized by a remarkable thermal resistance with heat deflection temperature (HDT) of over 90 °C. Nevertheless, due to its limited Young's modulus as well as its susceptibility to sudden degradation during melt processing, especially at high temperature, PBS is often blended and reinforced with other polymers, fillers and additives to tackle the issues of better processability, higher stiffness, and improved overall mechanical strength. Most common blends of PBS include poly(lactic acid) (PLA), another widespread compostable (and biobased) polyester, which is often added, in different proportion to PBS, to achieve tailored thermo-mechanical response behavior. Other additives and compatibilizers are also frequently used in PBS blends to achieve a wider processing window with better thermal resistance and better mechanical performance thanks to its customizable composition. Thus, recent advances in polymer blending processes have rendered PBS blends an interesting material platform for applications that require a balance of mechanical strength and flexibility as well as thermal resistance together with compliance to industrial compostability standards. This manuscript reviews briefly the synthesis routes of PBS together with the main thermo-mechanical and physical properties as well as recent progress in developing PBS-based blends for industrial applications. The challenges and future perspectives for the employment of PBS blends in every-day applications are also considered.