Abstract

This study presents an efficient method for producing biobased oligomers from waste cooking oils (WCOs), a renewable and sustainable feedstock. Epoxidized vegetable oils derived from olive (EOO), sunflower (ESO), and grape seed (EGSO) oils were copolymerized via ring-opening copolymerization (ROCOP) with cyclic anhydrides such as phthalic and maleic anhydride. The reaction was catalyzed using five ionic liquids as organo-catalysts, combined with tetrabutylammonium iodide as a cocatalyst. Among them, 1-butyl-3-methylimidazolium (ILI) showed the highest activity, allowing quantitative conversion at 80 degrees C within 1 h. The resulting oligomers (Ma(exp) 1021-1732 Da) were characterized by NMR, FT-IR, GPC, and TGA A mechanistic study supported by NMR and DFT calculations revealed that ionic liquids promote epoxy ring opening through hydrogen-bond stabilization. Overall, the work highlights ionic liquids as effective catalysts for the rapid synthesis of biobased oligoesters via ROCOP.