Synthesis and characterization of hyperbranched aromatic poly(ether imide)s with terminal amino groups

We synthesized an AB2‐type monomer, 4‐{4‐[di(4‐aminophenyl)methyl]phenoxy}phthalic acid, which contained one phthalic acid group and two aminophenyl functionalities. The direct self‐polycondensation of the AB2‐type monomer in the presence of triphenylphosphite as an activator afforded a hyperbranched poly(ether imide) with a large number of terminal amino groups. This polymer was characterized with 1H NMR and IR spectroscopy. The degree of branching of the hyperbranched poly(ether imide) was approximately 56%, as determined by a combination of model compound studies and an analysis of 1H NMR spectroscopy integration data. The terminal amino groups underwent functionalization readily. The solubility and thermal properties of the resulting polymers depended on the nature of the chain end groups. In addition, the hyperbranched poly(ether imide) was grafted with polyhedral oligomeric silsesquioxane (POSS). Transmission electron microscopy analysis revealed that the grafted POSS molecules aggregated to form a nanocomposite material. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3726–3735, 2003 The direct self‐polycondensation of a new AB2‐type monomer, 4‐{4‐[di(4‐aminophenyl)methyl]phenoxy}phthalic acid, in the presence of triphenylphosphite as an activator afforded a hyperbranched poly(ether imide) with chain‐ending amino groups. The degree of branching was estimated to be 56% on the basis of 1H NMR spectroscopy analysis. The amino groups at the chain ends were readily accessible to reagents in solution and were converted into a variety of functional groups. Transmission electron microscopy analysis revealed that the hyperbranched polymer grafted with polyhedral oligomeric silsesquioxane aggregates to form a nanocomposite material.