Use of ionic liquid as a convenient, rapid and eco-friendly method for synthesis of novel thermally stable aromatic polyamides containing imidazole pendent group

Ionic liquids (ILs) are organic salts that are generally liquid at ambient temperatures, preferably close to room temperature. Due to deterioration of the environment, green chemistry hasbeen receiving increasingly more attention since 1990s [1]. Recently, water and ILs have been recognized and areattracting attentions as eco-friendly solvents for organic and polymer synthesis. Wholly aromatic polyamides (PA)s are well known for their good mechanical properties, goodchemical resistance and excellent high-temperature stability that qualify them as high-performance polymeric materials.However, the rigidity of their backbones and strong hydrogen bonding result in high melting temperatures or glass transition temperatures and limited solubility in most organic solvents,which restrict their areas of application. Therefore, the preparation of soluble and/or thermoplastic PAs is of majorresearch interest. Many efforts have been made with the aim of making synthetic modifications of the rigid backbone byincorporation of flexible linkages, bulky pendant groups and non-coplanar or asymmetrical moieties