Strong, tough and aqua-degradable poly(glycolic acid)/poly (butyleneadipate-co-terephthalate) composites achieved by interfacial regulation

Poly(glycolic acid) (PGA) has displayed excellent tensile strength, degradability and renewability, but it still faces dilemmas in practical because of its low toughness, poor melt strength and the ease of thermal degradation. In this work, in order to take full advantages of its degradability and high strength, the PGA was toughened by poly(butyleneadipate-co-terephthalate) (PBAT) and reinforced by chopped carbon fibers (CFs) through melt compounding with the help of compatibilizers which facilitated the regulation of interfacial morphology and thereby performance. The evolution of tensile properties, dispersion state of PBAT domains, interface region and rheological behaviors of the blends were analyzed to explore the intrinsic improvement mechanism. Specifically, the increased grafting density of molecular chains revealed from the blend melt viscoelasticity was proposed to be responsible for the greatly enhanced toughness, resulting in an elongation at break of ∼90.45% and a toughness of 49.65 MJ/m3 which were dozens of times higher than PGA itself. Such blend is well capable of incorporating of CFs, showing an ultimate tensile strength ∼135 MPa whereas remaining ductility and aqua-degradability. Overall, this work provided a great potential in replacing metal alloys with the reinforced and toughened PGA composites for the applications of sacrificed tools. © 2025 The Authors