Gallic acid derivatives as stabilizers in cellulose solutions: analysis by 31P NMR spectroscopy

Abstract Lyocell dopes for cellulosic fiber manufacture, i.e., cellulose solutions in N -methylmorpholine- -oxide monohydrate, are commonly stabilized by propyl gallate, or alternatively recently proposed gallic acid amide derivatives. In this study, the analysis of stabilizer and its major degradation products, ellagic ellagoquinone, is investigated. The stabilizer-derived compounds readily extracted from with polar aprotic solvents without solvent interference. This followed derivatization OH groups a phosphitylation agent subsequent 31 P NMR analysis—an approach frequently used to differentiate quantify lignins. chemical shifts resulting phosphites reported structures derivatives discussed. offers straightforward way analyze chemistry process. Graphical abstract