Synthesis of biobased monomers and polymers

The project aim is to develop sustainable reaction pathways for the synthesis of bio-based monomers and, consequently, the development of polymers of biological origin. Vegetable originated substrates deriving from the agri-food sector are of particular interest. Additional benefit comes from the upgrading of waste materials, characterized by low cost and wide availability, into high added value products. Four lines of research are presented, two focused on the production of biobased olefin monomers suitable for chain-growth polymerization processes, while the other two are devoted to the generation of monomers useful for step-growth polymerizations. Synthetic endeavors were directed towards the production of vinyl monomers (olefins) for atom transfer radical polymerization (ATRP) processes. The ATRP technique relies on the establishment of a reversible activation/deactivation equilibrium between dormant species and growing chains mediated by a complex of a transition metal, which is usually copper. 4-vinyl guaiacol was successfully synthesised from vanillin with satisfactory yields through a green Knoevenagel-Doebner condensation. Efforts towards establishing a one-pot synthesis are being made with the objectives of minimizing cost and environmental impact. A telescopic synthesis of 4-vinyl guaiacol acetate was developed, affording the hydroxyl-protected monomer in a single step. Another olefin monomer is obtained from cinnamaldehyde through a condensation reaction with allylamine. Its controlled polymerization is under study. On the step-growth polymerization side, the production of amines from renewable phenols is under study. The method involves a three-step approach, involving a Blanc-Quelet reaction and subsequent amination. Amination of furfural to furfuryl amine was also studied, together with a coupling process with carbonyl compounds. Potential application of these monomers are as building blocks for non-isocyanate polyurethanes, epoxy resins, or polyamides. Another upgrading of furfural deals with its transformation towards an unsaturated diacid monomer, through an oxidative ring opening procedure.