Professor Sylvain Caillol and coworkers report on Sustainable Phenolic Thermosets from synthesis to characterization is excellent. The synthesized several phenolic resins using a dialdehyde and bio-based phenol. They way of characterization and insight determination of the mechanism is fascinating. The abstract and conclusions are also supported by the data, results, and discussion. It is worth mentioning that their findings will definitely earn much more attention to polymer society. So, it is recommended to publish in ACS Sustainable Chemistry & Engineering after minor revision listed in the comments.

Comments: 1. The synthesis of prepolymer using ethanol at the high-temperature section needs to discuss more with precaution and safety. 2. The NMR of the prepolymer needs to be assigned more precisely with the integration values. 2. The author said the rigidity of the current phenolic resin to phenol-formaldehyde resin is almost similar but is found to be different enough to mention or discuss.