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The inner soft portion of Borassus flabellifer L. (palmyra palm) wood was modified to study the effect of two-step densification, i.e. impregnation of thermosetting resin followed by compression through hot pressing on certain physical and mechanical properties. The phenol formaldehyde resin was impregnated into the wood using full-cell process followed by a compression process. Various physical and mechanical properties such as density, porosity, water absorption, volumetric swelling, modulus of rupture (MOR), modulus of elasticity (MOE) and compressive strength parallel and perpendicular to grain were evaluated. The results revealed that physical properties such as density, porosity, water absorption, volumetric swelling and mechanical properties such as MOR, MOE and compressive strength of the treated wood were better than untreated wood. The process can serve as a suitable method to enhance the utilisation potential of inner soft portion of palmyra palm. [ABSTRACT FROM AUTHOR]

Bamboo being a fibrous lignocellulosic material has been used in numerous applications including structural and nonstructural sectors. Currently, there has been lot of interest to use the bamboo in engineered composites such as laminated bamboo lumber (LBL) for various end uses. The processing parameters for producing bamboo composites have enormous effects on their properties and overall performance. The focus of the present work was to study the effect of two important hot pressing parameters, i.e., specific pressure (10–25 kg/cm2) and pressing duration (15–25 min) on various properties of the LBL prepared using thin strips of Dendrocalamus brandisii bonded together with phenol formaldehyde (PF) resin. Various physical and mechanical properties of LBL such as moisture, density, water absorption, thickness swelling, volumetric swelling, modulus of rupture (MOR), modulus of elasticity (MOE) and compressive strength parallel to grain and perpendicular to the glue line were evaluated. The results showed that pressure and pressing duration had significant effect on the physical and mechanical properties of LBL. For superior physical and mechanical performance, the pressure of 20 kg/cm2 along with the pressing duration of 25 min can be suggested for D. brandisii LBL bonded with PF adhesive. [ABSTRACT FROM AUTHOR]

Plantation-grown progenies of Melia composita Willd. were studied for variability in several physical properties: density, radial and tangential shrinkage, longitudinal permeability of heartwood and sapwood. Furthermore, flat-sawn planks from each of the progeny were subjected to a quick-drying test for determination of kiln-drying schedule. The mean density of the species was 0.39 g cm−3 and the wood may be categorized as light wood. Mean radial shrinkage (%) for the species was 2.8% with progeny-wise variation in radial shrinkage from 1.56 to 4.11%. Mean tangential shrinkage (%) for the species was 5.54% with progeny-wise variation in tangential shrinkage from 3.69 to 7.71%. The resultant tangential-radial shrinkage ratio was 1.98 (less than two), which suggests that the wood is relatively stable with respect to drying behavior. Mean sapwood and heartwood longitudinal permeability of the species were 3.38 and 2.02 Darcy, respectively. Higher longitudinal permeability of sapwood and heartwood indicate better drying and preservative properties of the species. Terazawa quick-drying test method suggests that the species is less susceptible to drying defects. During the test, only moderate checks and cracks were observed. A tentative kiln-drying schedule was recommended based on these results. [ABSTRACT FROM AUTHOR]