A5054386372- Wood Treatment and Properties
- Lignin and Wood Chemistry
- Natural Fiber Reinforced Composites
- Advanced Cellulose Research Studies
- Tree Root and Stability Studies
- Mechanical Behavior of Composites
- Material Properties and Processing
- biodegradable polymer synthesis and properties
- Bamboo properties and applications
- Polymer composites and self-healing
- Adhesion, Friction, and Surface Interactions
- Catalysis for Biomass Conversion
- Epoxy Resin Curing Processes
- Enzyme-mediated dye degradation
- Force Microscopy Techniques and Applications
- Forest ecology and management
- Plant Surface Properties and Treatments
- Biofuel production and bioconversion
- Electrospun Nanofibers in Biomedical Applications
- Optical measurement and interference techniques
- Nanocomposite Films for Food Packaging
- Forest Biomass Utilization and Management
- Corrosion Behavior and Inhibition
- Structural Analysis of Composite Materials
- Metal and Thin Film Mechanics
BOKU University
2016-2025
Kompetenzzentrum Holz
2023
Max Planck Institute of Colloids and Interfaces
2022
Material Sciences (United States)
2017
Institute of Wood Science and Technology
2012
Institute of Natural Resources
2006-2010
Erich Schmid Institute of Materials Science
2010
Austrian Academy of Sciences
2010
Montanuniversität Leoben
2010
Due to their high reactivity, chemical versatility and economic competitiveness, formaldehyde-based poly-condensation adhesives are used in huge amounts - 2010 the order of 20 million metric tons around globe, primarily wood-processing industry. Since 1970s formaldehyde emissions from products made thereof came under pressure were reduced continuously. The discussion intensified again initiated by latest European CLP (classification, labelling packaging) regulation, which into force 2016,...
Besides classical utilization of wood and paper, lignocellulosic biomass has become increasingly important with regard to biorefinery, biofuel production novel biomaterials. For these new applications the macromolecular assembly cell walls is utmost importance therefore further insights into arrangement molecules on nanolevel have be gained. Cell wall recalcitrance against enzymatic degradation one key issues, since an efficient plant material probably most crucial step in conversion energy....
Lignin-phenol-formaldehyde (LPF) resoles were prepared using different types of lignin at various levels phenol replacement by (0 to 40 wt.%). Adhesive properties including thermal behavior as determined differential scanning calorimetry (DSC), time-dependent development bond strength during hot pressing automated bonding evaluation system (ABES), tensile shear solid beech wood lap-joints, and free formaldehyde content the adhesives investigated. Preparation phenol-formaldehyde (PF) resole...
The functional characteristics of plant cell walls depend on the composition wall polymers, as well their highly ordered architecture at scales from a few nanometres to several microns. Raman spectra wood acquired with linear polarized laser light include information about polymer alignment cellulose microfibrils respect fibre axis (microfibril angle). By changing polarization direction in 3 degrees steps, dependency between and orientation was investigated. Orientation-dependent changes...
Hardness and elastic modulus of spruce wood cell walls parallel to their axial direction were investigated by means nanoindentation. In the secondary wall layer S2 individual earlywood compression tracheids, a systematic pattern variability was found. Several factors potentially affecting nanoindentation results investigated, i.e. specimen orientation related indenter tip, cutting during preparation, tip geometry, fibre inclination, respectively, finally micro fibril orientation. Mechanical...
Due to the increasing interest in applying a wider range of wood species for structural purposes, nine European softwood and hardwood (ash, beech, birch, hornbeam, larch, oak, poplar, black locust spruce) were assessed their ability be bonded with three different commercial adhesive systems (melamine–urea–formaldehyde, one-component polyurethane phenol–resorcinol–formaldehyde). Tensile shear strength delamination tests conducted according standards, all including corresponding as joints...
Three-dimensional scaffolds (3D) with controlled shape, dual porosity and long-term mechanical dimensional stability in biofluids are of interest as biotemplates tissue engineering. Herein, self-standing lightweight cellulose-based biogenic a spatially structured morphology, macropores interconnected micropores were fabricated using combination direct ink writing 3D printing freeze-drying techniques. This was achieved by developing water-based low-cost bicomponent based on commercially...
Wheat gluten, soy, potato and pea protein concentrates were studied to evaluate their wood bonding performance. The aim of comparing different plant proteins was find alternatives sufficiently available in Europe with comparable performance soy. Proteins subjected alkaline hydrolysis under conditions. relation between molecular weight, viscosity, solids content, solubility dispersions using proteins, which differ properties. Viscosity pH change tracked during indicating structure alteration...
Abstract Cross sections of wood adhesive bonds were studied by scanning thermal microscopy (SThM) with the aim scrutinizing distribution in bond line region. The conductivity, as well temperature area, was measured on surface means a nanofabricated probe offering high spatial and resolution. Both conductivity measurements found suitable to differentiate between materials region, i.e., adhesive, cell walls embedding epoxy. Of two SThM modes available, mode provided images superior optical...
Abstract The elastic modulus, hardness, and creep factor of wood cell walls in the interphase region four different adhesive bonds were determined by nanoindentation. In comparison with reference unaffected adhesive, from melamine-urea-formaldehyde (MUF) phenol-resorcinol-formaldehyde (PRF) showed improved hardness reduced creep, as well modulus case MUF. contrast, polyvinylacetate (PVAc) one-component polyurethane (PUR) more but lower than reference. Considering cell-wall penetration...
Lignin phenol formaldehyde (LPF) resols were produced using depolymerized lignin fractions at various levels of substitution (50 to 70 wt %). To produce monomeric-rich (BCD-oil) and oligomeric (BCD-oligomers) bio-based phenolic compounds, softwood kraft was base-catalysed degraded. These (BCD) building blocks further used substitute in the synthesis resins characterized detail (such as viscosity, free content, chemical composition, curing bonding behaviour). The adhesive properties compared...
Comparative analysis of the chemical and rheological curing kinetics formaldehyde-based wood adhesives is crucial for assessing their respective performance. Differential scanning calorimetry (DSC) rheometry are conventional techniques used monitoring processes leading to crosslinking polymerization adhesives. However, direct comparison these inappropriate due intrinsic differences in underlying procedures. To address this challenge, two adhesive samples were sequentially cured, firstly with...
Abstract Seven different polymers used frequently as adhesives and/or matrix in wood, wood composites, and natural fiber‐reinforced composites were studied by uniaxial tensile tests nanoindentation. It was shown that the elastic modulus, hardness, creep factor, elastic‐, plastic‐, viscoelastic work of indentation seven is essentially same regardless whether tested form pure films or situ , i.e., an adhesive bond line with spruce wood. An excellent correlation found between modulus measured...
Abstract The elastic modulus and Poisson's ratio of seven different polymers frequently used as wood adhesives and/or matrix in wood‐ natural‐fibre‐reinforced composites, respectively, were determined by means tensile tests. Specimen deformation during testing was measured a mechanical extensometer an electronic speckle pattern interferometry system, respectively. results from both methods show excellent correlation for the modulus. moduli studied cover wide range 0.47 GPa polyurethane to...