Microwave-Assisted Synthesis of Monohydroxy Pendant Polybenzobisthiazole Thermoplastic Polymer

The microwave-assisted synthesis method is a relatively new approach employed to reduce synthesis time and increase yield. In this study, we prepared PBZT polymer containing pendent hydroxyl moieties using the microwave-assisted synthesis method and, for comparison purposes, i.e., conventional vs chemical methods. The condensation reaction between 5-hydroxy isophthalic acid and 2,5-diamino-1,4-benzene dithiol (DABDT·2 HCl) was examined. Microwave-assisted synthesis has been demonstrated to significantly reduce reaction times and conserve energy when compared to traditional heating methods. Characterization of the synthesized polymers was performed using 13C solid-state NMR, FT-IR, and thermal analysis studies. Interestingly, DSC investigations revealed no glass transition temperature (tg) for the synthesized polybenzobisthiazoles. Furthermore, according to TGA measurements, the PBZT remained stable up to 400 °C in an N2 environment.