Processable Poly(Keto-Imide)s Having Bulky Pendent Ether Groups

1, 3-Bis(3-aminobenzoyl)benzene (BAB), 1, 3-bis(3-amino-4-phenoxybenzoyl)benzene (BAPB) and 1, 3-bis(3-amino-4-biphenoxybenzoyl)benzene (BABB) were synthesized from 1, 3-bis(3-nitro-4-chlorobenzoyl)benzene. By using these three diamines and commercially available tetracarboxylic dianhydrides such as 3, 3′, 4, 4′-benzophenone tetracarboxylic dianhydride (BTDA) and pyromellitic dianhydride (PMDA), several kinds of poly(keto-imide)s were synthesized. Thermal properties and processability such as melt-flowability and solubility in organic solvents of the obtained poly(keto-imide)s were investigated by focusing on the chemical structures of their repeating structure units. Inherent viscosities of poly(keto-imide)s ranged from 0.54 to 0.75 dl g−1. These poly(keto-imide)s displayed glass transition temperatures (T g) between 219 and 256 °C, and only the poly(keto-imide) prepared from BAB and PMDA showed a melting point (T m)at 451 °C. Melt-flowabilities of these poly(keto-imide)s except for BAB/PMDA poly(keto-imide) were observed between 285 and 330 °C. The poly(keto-imide)s having bulky pendent ether groups were soluble in chloroform, 1, 1, 2-trichloroethane, N, N-dimethylacetamide and m-cresol at ambient temperature.