Isabelle Roth, A. A. Jbarah, R. Holze
Feb 3, 2006
Citations
0
Influential Citations
13
Citations
Journal
Macromolecular Rapid Communications
Abstract
Summary: Nucleophilic aromatic substitution of 2,6-O-dimethyl-β-cyclodextrin (β-DMCD)-complexed 4-fluoro-3-nitroaniline derivatives with poly(vinyl amine) (PVAm) in water results in 2-nitro-1,4-benzenediamine-functionalized water-soluble PVAms in one step. The 2-nitro-1,4-benzenediamine moiety linked to the polymer is solvatochromic and undergoes protonation and deprotonation as function of pH as shown by UV-Vis spectroscopy. The occurrence of an isosbestic point in the UV-Vis spectrum is suitable to directly determine the pKa value using the Henderson-Hasselbalch equation. The influence of the methyl group substitution of the polymer and the 2-nitro-1,4-benzenediamine moiety on the pKa is discussed. Structure of the 4-N,N-dimethyl-2-nitro-1,4-benzenediamine-functionalized PVAm and its solution in water at varying pH.