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The anatomical, physical, and mechanical properties of 13 Malaysian bamboos and the trend of these properties along the bamboo culms’ height were examined. The results showed that these properties varied between the 13 species and they were also affected by the culm height. From the results obtained, the fibre morphology, as well as radial, longitudinal, and tangential shrinkage from green to oven-dry decreased from the basal to the top of the bamboo culm. In contrast, the opposite trend was observed for the density, modulus of rupture, modulus of elasticity, and percentage of the vascular bundle. The potential usage of 13 bamboo species is also considered.

Bulking treatment with low molecular weight phenol formaldehyde (LmwPF) resin has been found to successfully enhance the properties of low-density wood but emit higher formaldehyde. Incorporation of nanoparticle to the phenolic matrix could possibly reduce the use of high concentration LmwPF and thus lower the formaldehyde emission (FE) without adversely affecting the other properties. The aim of the study was to examine the characteristics of LmwPF resin and nanoclay admixture and determine its effects on the performance of impreg wood. Montmorillonite nanoclay nanomer (0.5-1.5 % w/w based on solid PF) was dispersed in LmwPF resin (10-20 % w/v) using ultrasonication technique. The dispersion of nanoclay in LmwPF was examined using X-ray diffraction (XRD) analysis and transmission electron microscopy (TEM). XRD and TEM analyses confirmed that the nanoclay dispersion in the resin was in exfoliated form. Air-dried sesenduk (Endospermum diadenum) wood was impregnated with these admixtures using vacuum pressure process followed by curing at 150°C for 30 min. The FE, dimensional stability and strength properties were evaluated and compared with impreg wood treated solely with LmwPF. The results showed that the polymer retention and density of the LmwPF/nanoclay-impregnated samples were higher than the LmwPF-impregnated samples. This admixture had successfully bulked the cell wall of the wood and imparted higher dimensional stability to the treated wood. The modulus of rupture and modulus of elasticity, compressive stress and hardness & Zaidon Ashaari

The objective of this study was to investigate the moisture content (MC), density, and amount of extractives along the height of a 32-year-old oil palm stem. The extractives were removed following TAPPI standards T-207 and T-280 for water solubility and acetone extractives. The results showed that the MC of the palm stem increased from the outer towards the inner section, while the density decreased. Along the tree height, the MC was found to increase from the bottom to the middle part, but slightly decreased towards the top. An inverse trend was obtained for the density distribution along the tree height. The results of the extractive separation showed that the middle and center sections of the oil palm stem contained the highest amount of extractives irrespective of the types of solvent. The highest amount of extractives was obtained from hot water extraction, followed by cold water and acetone extractions. The lowest amount of extractives was located at the bottom outer section of the oil palm stem which ranging from 2.0 to 9.2%, whereas the middle and center sections contained a greater amount of extractives ranged from 4.6 to 32.8% regardless of the type of solvent used.