Cationization of <i>Eucalyptus</i> Kraft LignoBoost Lignin: Preparation, Properties, and Potential Applications
Patrícia I. F. Pinto, Sandra Magina, Enkhjargal Budjav, Paula Pinto, Falk Liebner, Dmitry V. Evtuguin
Abstract
C NMR spectroscopy of the product obtained at this limit reactant concentration suggest introduction of 1.2 quaternary ammonium groups per C9 unit and substitution of 75% of the initially available phenolic OH groups. The possible contribution of benzylic hydroxyls to the introduction of quaternary ammonium moieties through a quinone methide mechanism has been proposed. Since both molecular characteristics and degree of substitution, and hence solubility or count of surface charge, of colloidal particles can be adjusted within a wide range, cationic kraft lignins are promising materials for a wide range of applications, as exemplarily demonstrated for flocculation of anionic dyes.