posted on 2020-03-18, 19:37authored byLinda Härdelin, Diana Bernin, Mikaela Börjesson, Anna Ström, Anette Larsson
Native
hemicellulose lacks many of the properties that make fossil
fuel-based polymers excellent for use in today’s industrial
products and processes. The mechanical and thermal properties of the
hemicellulose can, however, be modified, and its processability increased.
We functionalized galactoglucomannan to lower its glass transition
temperature (Tg) and thereby increase
its processability. The functionalization was achieved through an
etherification reaction with butyl glycidyl ether used at three molar
ratios. Films were produced, and their mechanical and thermal properties
were evaluated. Thermogravimetric analysis showed that increased substitution
increased the degradation temperature and decreased the water content
in the sample, implying increased hydrophobicity upon modification.
Dynamic mechanical analysis indicated that butyl glycidyl ether functionalization
alters the thermal properties of the modified films both in the absolute
values of Tg and in the strength of the
films. The etherification reaction resulted in a more ductile material
than the unmodified galactoglucomannan (GGM).