A new epoxy-based ink is reported, which enables 3D printing of lightweight cellular composites with controlled alignment of multiscale, high-aspectratio fiber reinforcement to create hierarchical structures inspired by balsa wood. Young's modulus values up to 10 times higher than existing commercially available 3D-printed polymers are attainable, while comparable strength values are maintained.

Wood cells, unlike most other cells in plants, grow by a unique combination of intrusive and symplastic growth. Fibers grow in diameter by diffuse symplastic growth, but they elongate solely by intrusive apical growth penetrating the pectin-rich middle lamella that cements neighboring cells together. In contrast, vessel elements grow in diameter by a combination of intrusive and symplastic grow...

Hot-water extraction of hemicelluloses, especially galactoglucomannans, from fractions of ground spruce wood with different particle sizes was studied at 170°C with extraction times up to 60 min. Extraction of spruce sapwood, heartwood, and thermomechanical pulp (TMP) was also compared at 160 to 180°C. Static batch extractions were carried out in an accelerated solvent extractor (ASE). The extr...

In this paper, measurement of wood grains is discussed. A number of image processing techniques are first applied to images of all four long surfaces of sawn lumber. This gives us the rates and directions of the visible grains, which enables us to estimate the actual thickness and 3D directions of wood fibers. These are very important indicators about the strength of the subject. In these exper...

The amount of wood residue is used as a measurement of the extent of wood liquefaction. Characterization of the residue from wood liquefaction provides a new approach to understand some fundamental aspects of the liquefaction reaction. Residues were characterized by wet chemical analyses, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and scanning electron microscopy (...

As wood treated with chromated copper arsenate (CCA) is removed from service, methods for eliminating toxic metals from the wood are needed. CCA-tolerant bacteria were evaluated for their ability to modify CCA-treated wood. Aerobic bacteria were isolated from a 20-year-old test plot of CCA-treated stakes. Bacteria selected for their ability to grow on nutrient agar containing CCA components, we...

The aim of the presented research work was to determine and analyze emissions volatile organic compounds (VOCs) from experimental lightweight wood fiber insulation board produced in dry technology. Until now, there have been no rigid materials made fibers such low density Among typical parameters as thermal conductivity mechanical performance board, attention also paid their influence on indoor...