Influence of acceptor functionality on charge transfer interactions in mixtures of poly(9-vinylcarbazole) with nitroaromatic compounds

Abstract

AbstractCharge transfer interactions in mixtures of poly(9-vinylcarbazole) with three nitro compounds (4,4′dinitrodibenzyl, ethyl 3,5-dinitrobenzoate and 2,2′,4,4′-tetranitrodibenzyl) were examined. GPC shows an increase of apparent polymer weight average molecular weight (MW) in mixtures compared with pure PVK. Electron acceptors show upfield 1H-NMR shifts for all mixtures. The equilibrium association constants (k) calculated from the Benesi-Hildebrand equation are 0.511, 1.371, and 1.868 L mol−1 for PVK blends with DNDB, DNBE and TNDB, respectively. Shifts of (−NO2) stretch vibrations in mixtures support charge transfer complex formation between PVK chains and electron acceptors The ability to accept electrons decreases: TNDB>DNBE>DNDB.