The glass transition temperature of isolated native, residual, and technical lignin
Journal article, 2024

The glass transition temperatures (T g) of native, residual, and technical lignins are important to lignocellulose pulping, pulp processing and side stream utilization; however, how the structural changes from native to residual and technical lignin influences T g has proven difficult to elucidate. Since the T g of macromolecules is greatly influenced by the molecular weight, low-molecular-weight fractions, such as milled wood lignin (MWL), are poor representatives of lignin in the cell wall. To circumvent this problem, lignins of both high yield and purity were isolated from Norway spruce and softwood kraft pulp using the enzymatic mild acidolysis lignin (EMAL) protocol. Technical softwood kraft lignin was also fractionated into groups of different molecular weights, to acquire lignin that spanned over a wide molecular-weight range. A powder sample holder for dynamic mechanical analysis (DMA), was used to determine the T g of lignins, for which calorimetric methods were not sensitive enough. The T gs of EMAL were found to be closer to their in situ counterparts than MWL.

dynamic mechanical analysis

Thermoplastic properties

lignocellulose

Kraft pulping

Author

Åke Henrik-Klemens

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Fabio Caputo

Chalmers, Life Sciences, Industrial Biotechnology

Roujin Ghaffari

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Gunnar Westman

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Ulrica Edlund

Royal Institute of Technology (KTH)

Lisbeth Olsson

Chalmers, Life Sciences, Industrial Biotechnology

Anette Larsson

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry

Holzforschung

0018-3830 (ISSN) 1437-434X (eISSN)

Vol. 78 4 216-230

Design for Circularity: Lignocellulose based Thermoplastics - Fib:Re

VINNOVA (2019-00047), 2020-01-01 -- 2024-12-31.

Subject Categories

Wood Science

Paper, Pulp and Fiber Technology

DOI

10.1515/hf-2023-0111

More information

Latest update

4/27/2024