STUDY OF REDUCING DESTRUCTION OF LIGNIN BY FT-IR SPECTROSCOPY

Abstract

Lignin preparations were obtained from harsh flax fiber and material exposed to an alkaline solution of borohydride sodium using the Bjerkman extraction method. Peaks of individual vibrational processes of all types of covalent bonds in the functional groups of the biopolymer were identified. The mechanism of induced lignin destruction as a result of destabilization of the ether bond adjacent to the reduced carbonyl group in the propane link of the macromolecule was confirmed. The reduction of carbonyl is accompanied by a twofold increase in the intensity of the absorption band of alkyl hydroxyls and a fourfold increase in the number of hydroxyaryl groups, which indicates to the accumulation of structural units in the free phenolic form in the system. The dynamics of structural transformations was compared, and the duration of the serial-parallel processes of polymer reduction and destruction was estimated.