Research

Considering the pressing global challenges posed by climate change and the plastic waste crisis, there is an urgent need for researchers to address environmental issues. This requires exploring alternative resources and adopting novel approaches to minimize waste generation and replace oil-based, non-degradable plastics with renewable and sustainable bio-based alternatives. A highly promising source for the latter purpose is agri-food by-products. Despite their abundance —the annual production of wheat straw and corn stover equals almost 3000 Mt—their efficient valorization and processing into shapeable and strong materials remains a major challenge. The research hypothesis of the here-submitted research project SusFoMa is that accruing lignocellulosic feedstocks can be directly processed into precursors of cellulose nanofiber-reinforced thermoplastics by a sustainable chemical approach. The proposed chemical modification is based on esterification approaches, which can be controlled to selectively modify the biopolymer matrix of locally available food waste, such as corn stover and sugarcane bagasse, transforming these secondary biomass streams into moldable biopolymers. Our proposed chemical modification is based on esterification techniques, which allow us to selectively modify the biopolymer matrix of locally available food waste, such as corn stover and sugarcane bagasse. By doing so, we aim to convert these secondary biomass streams into moldable biopolymers. What sets our method apart from previous approaches is our emphasis on preserving the structural integrity of cellulose nanofibers. These nanofibers, known for their exceptional mechanical strength, are the smallest building blocks within the cellulose fiber of plant cells. SusFoMa aims to utilize these nanofibers to create high-performance bioplastics that are competitive in the market.

Project "Flame retardant treatment of wood using supercritical carbon dioxide" (FFG, Bridge-1 program, project number FO999903628) is a network project between BOKU, Kompetenzzentrum Wood KPlus and the companies NATEX (Austria) and Fritz Kohl GmbH & Co. KG. The impregnation of technical veneers with high-performance flame retardants using supercritical CO2 as a carrier medium is to be investigated with the aim of using these veneers in aircraft, automobile and shipbuilding. In the 3-year's project, R&D work is carried out in 4 central work packages (in addition to the APs Management and Dissemination). Based on a comprehensive literature study (WP 2) on P- and N-containing high-performance flame retardants, accompanying experiments investigating their dissolution and transport behavior in scCO2 as well as experiments targeting the introduction of functional groups for improved solubility or chemical fixation in wood, a selection of promising flame retardants for further work in WP 3-5 will be made. For these compounds, investigations into the solubility and transport behavior in scCO2 will be carried out in AP 3. This work allows the identification of particularly promising FSM and impregnation conditions (p, T, relaxation regime). Subsequently, tests are carried out to impregnate wood veneers, technical veneers and small solid wood samples in order to evaluate the loading success qualitatively and quantitatively. Accordingly, these tests are accompanied by comprehensive analysis, which serves to demonstrate the homogeneity of the loading, the degree of loading and the influence of the treatment on essential material properties. Data from these experiments can be used to draw important conclusions about improving process control. Finally, in WP 5, flame protection-relevant, mechanical, olfactory, morphological and colorimetric parameters will be collected for selected samples in order to finally evaluate the practical suitability of scCO2-supported impregnation of wood veneers and its transfer to solid wood. .

The Josef Ressel Center “ReSTex – Recovery Strategies for Textiles”, addresses one of the central issues on the way to more sustainable societies and bioeconomies: the recycling of textiles. The focus is on utilization of cellulosic textiles and the separation of cellulosic blends, such as cotton / polyester, the so-called “polycotton”. The Ressel Center is located at the University of Applied Sciences Wiener Neustadt, Biotech Campus Tulln and will tackle the scientific challenges of the topic together with its scientific partners, two institutes at the University of Natural Resources (BOKU) and one at TU Vienna, and four partner companies. Two general recycling routes will be explored: first, the selective dissolution of cellulosic blended textiles aims at separating the cotton and PET fractions in polymeric form without extensive degradation. Second, cellulose hydrolysis by biotechnological methods converts cellulose to fermentable carbohydrates while purifying out the PET fraction from polycotton blends. Initial work phases address screening and characterization of the starting textile blends, as well as evaluation of requirements for recycling. A database of spectral analysis data will be established and processed by AI. Several pre-treatment methods and special cellulose solvents for separation of cotton-rich articles will be tested. Follow-up work optimizes the solvents/solvent systems towards improved selectivity, suitable conditions for minimal impact on polymer integrity in case of high cotton fractions.