a Cellulosic fibers were efficiently disintegrated from bamboo pulp as raw material and then oxidized using sodium periodate to introduce dialdehyde groups on their surfaces. The resultant fibers were characterized using Fourier transform infrared spectroscopy (FT-IR), Xray diffraction (XRD), and thermogravimetric analysis (TGA). FT-IR spectra demonstrated that the characteristic absorption band of aldehyde groups was present at 1735 cm -1 , confirming that aldehyde groups were successfully introduced. XRD showed that the nature of bamboo pulp fibers changed slightly after oxidation, except in the reduction of crystallinity. The aldehyde content increased with the sodium periodate content and reached a maximum of 1.41 mmol/g. The yield loss maximum was 32.4 wt%. TGA results showed that the temperature at the initial and final decomposition of the oxidized fibers was subject to the periodate dosage and that the thermal stability decreased to some extent.

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Coating quality for scrimber products against exterior conditions is largely dependent on the surface properties. The wettability, morphology, and chemical composition of pine scrimber surfaces were investigated to better understand the surface properties. The scrimber was found to be a hydrophilic material because the water contact angles were less than 90°. The panels with a density of 1.20 g/cm3 had the largest angle change rate (k = 0.212). As the panel density increased, the instantaneous contact angle of each test liquid (i.e., water, formamide, and diiodomethane) on the panels decreased, and so did surface free energy. Panels with higher density showed lower surface roughness. Surface roughness across the wood grain was greater than that along the grain. SEM observations showed the high-density panels had a smoother surface with fewer irregular grooves in comparison with the low-density panels. X-ray photoelectron spectroscopy (XPS) analysis indicated that more unoxygenated groups appeared on the surface of high-density panels.

Natural wood has certain advantages such as good processability and high specific strength and thus has been used for millennium as a structural material. But the mechanical performance and water resistance, particularly for fast-growing species, are unsatisfactory for high-end applications. In this study, the “new-type” scrimber technology was introduced to radiata pine (Pinus radiata D. Don) scrimbers. The structure, mechanical properties, and dimensional stability of the scrimber panels were investigated. Results showed that OWFMs as basic units of scrimber had been very even in size and superior permeability. The scrimbers exhibited a three-dimensional porous structure, and the porosity had a decrease with increasing density. Both OWFMs and densification contributed to the high performance in terms of mechanical properties and water resistance. The flexural, compressive, and short-beam shearing strength were significantly enhanced with increasing density. As the density was 0.80 g cm−3, the flexural strength (MOR) was approximately 120 MPa, much larger than many selected wood-based panels. Moreover, the water resistance and dimensional stability also were closely related to the density. At the density of 1.39 g cm−3, the water absorption rate and thinness swelling rate of the panels in boiled water were only 19% and 5.7%, respectively.