Synthesis and characterization of thermostable polyamides from unsymmetrical diamines containing flexible ether linkage and different diaryl imidazole pendants in ionic liquids

Analyzing the application of ILs in polymer synthesis proves their efficiency, so various polycondensation processes were successfully accomplished in ionic medium as well[1].Aromatic polyamides are used in applications demanding service at enhanced temperature while maintaining theirstructural integrity and an excellent combination of chemical, physical and mechanical properties. However, these polyamides encounter processing difficulty due to theirinfusibility and poor solubility in organic solvents [2]. The reasons for processing difficulty are inherent macromolecularrigidity, strong interchange forces, or semicrystallinity. Many studies have attempted to enhance their solubility and processability by introducing bulky side groups or flexiblechains into the polyamide backbone, or breaking its symmetry and regularity, or destroying the hydrogen bonding by Nsubstitutionwith certain groups such as methyl. These can increase the flexibility, lower the melt point, and improve thesolubility of polymers[3, 4].