Pushing the Limits in Alcoholysis of Waste Polycarbonate with DBU-Based Ionic Liquids under Metal- and Solvent-Free Conditions

The development of efficient and green protocol for recycling of waste plastics is of great significance in terms of sustainable society and green chemistry concepts. Several ionic liquids (ILs) with different acidity-basicity and structures were one-step synthesized and characterized. They were applied to alcoholysis of polycarbonate (PC) without metal and solvent. The IL structures and reaction conditions were optimized. Moreover, the alcohol scopes and catalyst reusability were evaluated. The results showed that 100% PC conversion and 99% bisphenol A (BPA) yield were obtained by using [HDBU] [LAc] catalyst, and the [HDBU][LAc] could keep high-activity after using for six times under the optimized conditions. Finally, the possible reaction mechanism was proposed via the FT-IR and NMR analysis technique.