Abstract
In this study, a series of aromatic hyperbranched polyester (Ar.HBPs) of different generations (G1-G4) were synthesized using one-shot solution poly condensation, and their structural, physical, thermal and optical properties were studied in detail. The formation of aromatic ester bond in the product was confirmed using spectral analyses (FTIR and NMR). Ar.HBP reaction kinetics was studied from the changes in acid-to-ester band using FTIR and the optimal reaction time is around 21 hr (G1), 26 hr (G2), 29 hr (G3) and 31 hr (G4). DSC thermal data revealed their glass transition temperature at around 120 oC. From TGA data, thermal degradation (T10, oC) of Ar.HBPs started at around 216 oC (G1), 230 oC (G2), 241 oC (G3) and 243 oC (G4). MALDI-TOF investigation confirmed the chemical structure and molecular weight of the synthesized Ar.HBPs. Their optical property was revealed in the UV region by the existence of a broad absorption peak at 580 nm. From the aforementioned characterization studies, the synthesized Ar.HBPs supported the formation of a highly branched structure and an improvement in thermal stability with increasing HBP generations from G1 to G4. Ar.HBP (G1-G4) synthesis reported in this work will serve as a guideline for understanding their reaction kinetics, and the influence of their final properties on applications such as energy materials, optoelectronic materials and devices.