Research on electron donor-acceptor (EDA) association reaction of PVKs characterized by special tacticity with polynitrofluorenone

The electron donor-acceptor (EDA) association constants for the reaction of poly (N-vinylcarbazole) (PVK) samples, prepared under three conditions respectively, or their model compound, N-ethenylcarbazole (NECA), as a donor, and polynitrofluorenone as an acceptor and the molar absorption coefficients of their products have been determined. By analysis of ¹H NMR of PVK quantitatively, the isotactic sequence's percentage X₁ is estimated. The association constants K may be given by K=K₁X₁+K₂X₂, where the subscripts 1 and 2 denote the isotactic and syndiotactic sequence of the polymer respectively. From the principle of spectral analyses has been deduced the following relationship: Kε =K₁X₁ε₁ +K₂X, ε₂, and estimated the values for K₁, K₂, ε₁ and ε₂ where ε is the molar absorption coefficient.