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 degrees C, and only the poly(keto-imide) prepared from BAB and PMDA showed a melting point (T-m) at 451 degrees C. Melt-flowabilities of these poly(keto-imide)s except for BAB/PMDA poly(keto-imide) were observed between 285 and 330 degrees 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.