Strategies for the Functionalization of Polyhydroxyalkanoate Chains. Toward New Polyhydroxyalkanoate-Based Graft Copolymers

In recent years, biodegradable bio-based polymers have attracted significant attention as potential alternatives to petroleum-derived plastics. Among them, poly (lactic acid) (PLA) is the most well-known and widely utilized; however, its biodegradability, especially in marine environments, has been frequently questioned. In contrast, polyhydroxyalkanoates (PHAs) -notably polyhydroxybutyrate (PHB)- are bio-based and biodegradable polyesters that do not present this limitation. To expand the scope of PHAs applications, researchers have explored the strategy of grafting polymer chains onto the PHA backbone. Since the PHA backbone lacks inherent functional groups, it’s sometimes necessary to functionalize it to introduce reactive sites that allow for subsequent grafting of polymer chains. This review outlines the various synthetic approaches used to obtain functionalized PHAs and PHA-based graft copolymers, as well as their potential applications in the biomedical sector.