Enhanced superquenching of the hyperbranched conjugated polymer for the detection of nitroaromatic explosives

Carbazole-based linear conjugated polymer (P1) and hyperbranched conjugated polymer (P2), were successfully synthesized with high molecular weights and good solubilities through Sonogashira coupling reactions. Compared with P1, the charactyeristics of P2 were remarkably changed by exhibiting outstanding thermal stabilities and different emission behaviors. In this work, a superquenching effect was observed in the TNT-detection process by using PI The calculated Stern-Volmer quenching constant revealed that P2 was more sensitive than Pi towards TNT in solution, owing to the hyperbranched structure of P2 had multiple exciton migration channels and diffusion pathways via numerous branches in the two-dimensional (2D) space. Simultaneously, quenching efficiency of P2 was higher than that of P1, due to hyperbranched structure of P2 had multiple exciton migration channels. (C) 2016 Elsevier B.V. All rights reserved.