Oxidative Modification of Cellulose
PI Potthast, A.
The aim of the planned work is to achieve lean, cost-efficient and green chemical routes to improve the properties of kraft pulp for thermoplastic materials. The cellulose chain is intrinsically rigid, which is one of the causes of its high glass transition and melting temperatures. The offered research targets to increase the mobility of the cellulose chain through oxidation chain cleavage methods, that decrease H-bonds in which the anhydroglucose units are involved and induce a major release of molecular motions within and between the chains.

Lignin Binder
PI Potthast, A.
The aim of the development in the project “Lignin as a binder” is to modify or select lignin (as raw material) in such a way that it can be used alone or in combination as a binder for wood-based materials. Different lignins will be tested and analysed to establish valid structure-property relationships. In addition to the analytical characterisation, special application tests are carried out which can show suitability even outside of an analytical scale.

5D-Click-Druck zur Herstellung von Strukturen mit Mechanischen und Funktionellen Gradient
PI Beaumont, M.
The research hypothesis is the development of a novel gradient printing approach, named 5D Click Printing, combining cutting-edge bioprinting technology with state-of-the-art materials and crosslinking chemistry. This will be realized by using functional nanocellulose and polyoxazoline as ink formulations to produce 3D objects with mechanical (+1D) and functional gradients (+1D). The proposed ink formulations are based on functional cellulose nanofibrils and polyoxazolines.

Mechanical and functional gradients are reasons for the abundance of functionalities and extraordinary mechanical properties in nature. Mechanical gradients are spatial smooth transitions from mechanically weak to strong structures resulting in materials with remarkable mechanical performance. In case of the in vivo cell environment, the extra-cellular matrix, there are not only mechanical gradients present but also functional gradients, such as an increasing concentration of a bio-active molecule in one dimension. These gradients play an important role in the organization of cells into functional tissues and organs. The imitation of these multidimensional structures by biocompatible and shapeable materials in a straightforward way is a critical challenge that will be addressed in this proposal. The research hypothesis is the development of a novel gradient printing approach, named 5D Click Printing, combining cutting-edge bioprinting technology with state-of-the-art materials and crosslinking chemistry. This will be realized by using functional nanocellulose and polyoxazoline as ink formulations to produce 3D objects with mechanical (+1D) and functional gradients (+1D). The proposed ink formulations are based on functional cellulose nanofibrils and polyoxazolines. These materials were chosen because of their established biocompatibilities, printabilities and the resemblance to the two main components of the extra-cellular matrices, fiber-forming proteins and non-fibrous glycoproteins. The functional groups on the polymers were carefully selected to allow gelation by spontaneous click chemistry, which can be conducted in the presence of living cells. The 5D Click Printing technology will be further developed to fabricate multidimensional hydrogels with various functionalities. These gels will be used to assess and compare diverse characterization techniques to establish a methodology to visualize gradients in multidimensional objects. In conclusion, the developed technology will be the first straightforward avenue to shaped hydrogels with functional and mechanical gradients. 5D Click Printing will be used to fabricate, bioinspired and sophisticated tissue models for biomedical application, and to produce graded membranes for chromatographic separation of complex biopolymer mixtures.

Mid Sweden University, Sweden

Can triboelectricity provide more effective respiratory protection against viruses?
From November 2020 to May 2021
Dr Christina Dahlström
Funding agency: Vinnova (Sweden’s Innovation Agency) 
A research group at the FSCN research centre, Mid Sweden University will develop more effective filter materials for respiratory protection that can be used to reduce the spread of viruses, similar to Cov-SARS-2, to counter pandemics. The respiratory protection is based on cellulose material with triboelectric properties, which makes it easier to breathe than with today’s respiratory protection.

More info can be found on the press release, click here.
Illustration: Fredrik Dahlström.