The usage of renewable resources has become a hot topic upon the rising global awareness against fossil feedstock consumption. Lignin, the 2^nd most abundant natural polymer on Earth, is an aromatic biomacromolecule that holds a tremendous potential for the synthesis of biobased materials. The production of monomers and polymers from lignin has been investigated for years and keeps on expanding, as proven by the flourishing literature. However, the sustainability of the synthetic reactions has not been systematically analyzed. Herein, green chemistry plays a vital role in this area and provides several tools to design eco-friendly production methods. This critical review first describes the preeminent approaches for the synthesis of biobased monomers and polymers from lignin-derived compounds. In the second part, the “greenness” aspects of the 175 key monomer synthetic methods and 32 polymerization methods are evaluated based on selected criteria, including waste generation, atom efficiency, energy efficiency, usage of safer solvents, and biocatalytic methodology. The accessible green metrics, such as environmental factor (E factor) and atom economy are calculated to measure the greenness and to provide a quantitative base for strategic decisions. Furthermore, this study provides insights for the improvement opportunities and lights up the room for further developments. This review, aiming at scientists, industries and investors, strives to provide a critical outlook for the existing synthetic methods and motivates researchers to call for the integration of sustainability factors.

The sustainability of polymer microparticle production processes was evaluated. A different viewpoint was provided to encourage researchers to use simple yet effective green chemistry metrics calculations in the development of these processes.

The quite recent, yet quickly expanding, norbornene-levoglucosenone-based monomer family was extended to include a novel bi-functional methacrylate monomer that can be readily synthesized through a chemo-enzymatic pathway. The norbornene moiety was selectively polymerized via ring-opening metathesis polymerization (ROMP) under ambient conditions where Cyrene™ was explored for the first time as a green bio-alternative organic solvent for ROMP reactions. The activity of the metathesis catalysts was finely tuned in Cyrene™, versus common and toxic solvents such as dichloromethane, resulting in highly thermostable functional polymers with a T_d5% up to 401 °C and a T_g of −16.8 °C.