DIFFERENT TYPES OF PHENOLIC UNITS IN LIGNINS
Journal article, 2011

The influence of cross-linking and branching on the number of interconnections between lignin units and the number of end groups (phenolic and non-phenolic) in the lignin molecules is discussed. Branching results in an increased number of end groups. It appears from an evaluation of the literature that p-hydroxyphenylpropane units are phenolic to a larger extent than guaiacylpropane units and that such units in turn are phenolic to a larger extent than syringylpropane units. It is proposed that this is related to the relative oxidation potentials of the lignin units. Guaiacylpropane units C-substituted in the 6-position are phenolic to a large extent. Alternative explanations for this are presented.

Lignin

thioacidolyses

End groups

Phenolic units

ray crystallographic investigations

compression

spruce lignin

model

conformation

Cross-linking

wood

ethers

spectroscopy

oxidation-products

pine compression

Author

Knut Lundquist

Chalmers, Chemical and Biological Engineering, Organic Chemistry

J. Parkas

BioResources

1930-2126 (ISSN) 19302126 (eISSN)

Vol. 6 2 920-926

Subject Categories

Chemical Sciences

More information

Created

10/7/2017