PHOTOCONDUCTIVITY AND STRUCTURAL CHARACTERIZATION OF FULLERENATED PVKBR POLYMER

The influence of chemical modification (fullerenation) on structure an d photoconductivity in brominated poly(N-vinylcarbazole)(PVKBr) has be en described. The characterization techniques employed are UV-Visible, FT-IR, TGA, DTG, C-13 CP/MAS NMR, XRD and SEM. The fullerenated PVKBr has a visibly deep-brownish yellow cast when compared with the unreac ted polymer. PVKBr. Its UV-Visible absorption spectrum, in which the m ain bands center at 191, 195, 215, 229, 240, 265, 297, 331 and 345 nm, tends to move to the longer wavelength in compared that of the PVKBr and the peak range also extended from about 300 to 860 nm. The X-ray d iffraction evidence indicated that X-ray diffraction structure of full erenated PVKBr differs greatly from that of PVKBr arising from the cov alent attachment of C-60 to the brominated PVK backbone. The decreased photogeneration efficiency of fullerenated PVKBr might be thus linked to this conformational complication. The photo-induced discharge of p ure PVK, PVKBr, C-60-PVK, and C-60-PVKBr are found qualitatively in th e following order: 3.85% C-60-PVK >> PVKBr > 3.85%C-(60)-PVKBr > pure PVK under the same experimental conditions. Copyright (C) 1996 Elsevie r Science Ltd