Biobased reversible network from lignin/cellulose via Diels-Alder click chemistry

This thesis aims to address the growing demand for sustainable materials by developing novel reversible thermosets suitable for surface coatings. The primary objective is to create fully biobased materials which can contribute to the reduction of fossil-based materials and at the same time promote a circular economy through post-use recovery and reutilization. The utilization of the Diels-Alder (DA) reaction offers a promising path for designing thermoreversible materials. In this context, a series of biobased (thermoreversible) gels was synthesized using lignin and cellulose as starting materials. Lignin and cellulose were selected for their abundance in nature, with lignin, typically a byproduct of the paper industry and often underutilized, presenting an excellent opportunity for valorization. Cellulose, recoverable from sewage, was chosen as a sustainable alternative to virgin raw materials. This work is focused on the synthesis of these materials and on the optimization of their reversibility by the investigation of various parameters, including the incorporation of bismaleimide bridges, reaction temperature, and crosslinking density. The ultimate objective is the production of versatile thermoset materials applicable for surface coatings, adhesives, or self-healing materials which can be easily recovered after their use and that present an eco-friendly alternative to traditional coating materials.