Ring‐opening (co)polymerization of cardanol glycidyl ether

Abstract

AbstractThe anionic ring‐opening copolymerization of commercially available bio‐based cardanol glycidyl ether (CGE) was investigated without any prior purification. As a first step, anionic‐ring‐opening homopolymerization was attempted through active chain‐end and monomer‐activated mechanisms. Both strategies were unsuccessful. Conversely, in a second step, the anionic alternating ring‐opening copolymerization (AAROP) of CGE with the renewable N‐acetyl homocysteine thiolactone (NHTL) was successfully carried out in the presence of a strong base. Anisole, a solvent classified as sustainable and rarely used in anionic ring‐opening polymerization, proved to be a suitable for the AAROP. This polymerization is an unusual example of synthesis of linear polyesters with cardanol‐based monomers. The copolymers were carefully characterized by 1H, 13C, COSY, HSQC, 1H‐15N NMR and MALDI‐ToF, demonstrating an alternating structure. Then, CGE was copolymerized with NHTL and another additional epoxide. The cardanol‐derived monomers enable the preparation of functionalizable poly(ester‐alt‐thioether) bearing multiple allyl and alkene groups. The AAROP method in anisole offers new opportunity for green anionic polymerization through the use of sustainable chemicals, witnessed by the valorization of cardanol‐derived compounds and expands the scope of synthesized renewable polyesters.