Last week, Innventia’s Jasna Stevanic Srndovic submitted her thesis on interactions between polymers in the cell wall of spruce wood fibres. The new knowledge in this area contributes to making existing paper industry processes more efficient and to develop new materials from biopolymers. The driving force behind her work is to find means to make better use of the earth’s resources in a sustainable way.
The threat of global warming and limited fossil resources calls for ways to better use our resources. One way could be to streamline industry processes, such as in the paper industry, by reducing energy consumption in the production of thermomechanical pulp (TMP). This can be done by applying various chemical and / or enzymatic pretreatments of wood. Jasna’s thesis presents results that provide a better understanding of polymer interactions within the primary cell wall of spruce wood fibres and its implications for the energy demand in the refining process. She demonstrates how applying a low degree of sulphonation pre-treatment to spruce wood chips caused a weakening of these molecular interactions, as well as an increased softening and swelling of the material, thereby reducing the energy consumption within the refining process.
Another way to better protect the environment is to use renewable resources to a greater extent. Large quantities of polymers, such as cellulose, hemicelluloses and lignin, recovered from residual materials from the paper industry and agriculture, can be used to produce new renewable packaging materials. In her work, Jasna has investigated the ultrastructure of the secondary cell wall of spruce wood fibres, and has tried to imitate the structures found in wood fibres by preparing biocomposites and evaluating these as packaging materials.
“Nature’s unique material structures have many excellent qualities,” explains Jasna. “For example, they can withstand variations in climatic conditions. By attempting to imitate these synthetically, it may be possible to develop new bio-based materials with adapted qualities. I’ve produced hemicellulose films with improved mechanical properties by strengthening these with nanocellulose.”
“Increased knowledge regarding the interactions between the wood polymers is very important in order to be able to separate these in a better way, for use in new materials and other applications,” says Lennart Salmén, head of the Fibre and Material Science group at Innventia.
“Working towards a more sustainable society is the driving force behind my work and I hope the results will find an application in the industry”, concludes Jasna.
Jasna Stevanic Srndovic work is largely financed by Formas Wood Wisdom NET and the Wallenberg Wood Science Centre.