Bioderived thermosetting polymers and their nanocomposites: current trends and future outlook

The overwhelming need for thermosetting polymers in high-end products is well-recognized in the literature. The overdependence of thermosetting polymers on the petroleum resources for their synthesis is a matter of environmental concern. Considerable efforts have been put forward by the research community for making partially or completely bio-based thermosetting polymers for various applications in accordance with sustainable development goals. One of the sustainable strategies is to maximize the utilization of naturally available sources to improve materials' properties. The use of biomass for the synthesis of thermosets not only improves performance and reduces costs but also reduces pollution and negative impact on the environment. Herein, a systematic overview of the current advancements on bio-based thermosetting polymers such as epoxy resins, polyurethanes, and phenol-formaldehyde resins has been presented. Various bioresources for the development of the monomers and crosslinking agents for these popular thermosetting polymers have been discussed. The properties of the bio-based thermosetting resins from various sources are compared with the conventional resins. Finally, the future outlook of such promising bio-based thermosets is prospected, which would satisfy the need for a sustainable society.