Mechanically Strong and Tough Plant Oil-Based Poly(ester amide) Vitrimers with Closed-Loop Recyclability

Replacing traditional petroleum-based plastics with degradable biobased plastics has become one of the significant strategies to address energy shortages and environmental issues. Nevertheless, it still remains a scientific challenge to develop biobased plastics with ultrastrong mechanical strength and superior recyclability. Here, the catalytic conversion of Sapium sebiferum oil (SSO) to 9,10-dihydroxy-octadecanoic acid (C18-OH) monomer is first designed. Simultaneously, a novel biobased plastic, namely, PEA, is fabricated by a dual network through one-pot melt-polymerization, which exhibits mechanical performance higher than most commercial plastics and other reported PEAs. Benefiting from the synergy of the dynamic nature of H-bonds and hydroxy-ester bonds as well as the flexibility of the long aliphatic chain, the PEAs exhibit exceptional repairability and reprocessability. More importantly, PEAs can be efficiently degraded into the original reagents and the cross-linked materials can be reconstructed by the recovered monomers without losing the pristine performance. Additionally, abundant polar groups provide excellent adhesion properties for PEAs with a high shear strength of 10.29 +/- 0.21 MPa. This work unveils an elegant and efficient synthetic route to fabricate impressively robust and chemically recyclable materials as promising alternatives to conventional plastics.