Surface Characteristics and Acoustical Properties of Bamboo Particle Board Coated with Polyurethane Varnish

Using bamboo particle board as a wall divider, a furniture component, or an automotive component with a sound absorber function may be a viable option for architects and engineers seeking to achieve desired acoustical qualities, including noise reduction. However, there is still a dearth of research on the effect of particle board finishing and coatings on acoustical sound absorption and noise reduction qualities. This study, therefore, aims to determine the surface characteristics and acoustical properties of bamboo particle board, coated with polyurethane (PU). The single-layer homogeneous particle boards were constructed using particles classified as fine and coarse with two different board densities, and coated with a high-quality PU lacquer. This study found that the coating treatment of 0.3 mm 0.6 mm succeeded to significantly decrease surface roughness, as well as thickness, swelling, and water absorption, with the thickness coating as a dominant factor compared with board density and board particle size. Adding a PU coating increases sound absorption performance at low frequencies, but significantly reduces acoustical properties at high frequencies. The increase of particle board density leads to the decrease in noise reduction coefficient capability. Results obtained from this study are useful to determine the optimal coating thickness in terms of evaluating acoustical panel products.

Size Effect of Core Strands on the Major Physical and Mechanical Properties of Oriented Strand Boards from Fast Growing Tropical Species

Oriented strand board (OSB) is generally used for sheathing in residential walls, floors, and roofs. Because of its low pricing and utilisation of tiny diameter logs from fast-growing trees and thinning logs as raw materials, OSB is anticipated to gain popularity. In chapter, board properties of OSB using smaller strand size of Leucaena leucocephala as core layer had been studied. Small strand size of S3 (length = 75 mm, width = 3.2 to 6.3 mm) was located in the middle layer of the board while bigger strand sizes of S1 (length = 75 mm, width = 12.7 to 19.0 mm) and S2 (length = 75 mm, width = 6.3 to 12.7 mm) were located at the face and back layers. Utilization of smaller strands (S3) in the middle layers may yield boards that have better physical and mechanical properties. Except for MOR in the minor axis, board density and resin content were shown to have a substantial impact on physical and mechanical properties. Except for MOR in the major axis, strand size had little affected on physical and mechanical properties. The effects of board density on mechanical properties were discovered to affect significantly different. With a positive correlation, board density had a significant effect on thickness swelling. Between S1+S3 and S2+S3 strand size, there is no significant effect on bending properties, internal bond strength and thickness swelling. The effect of resin content on bending properties revealed a significant difference of MOR in major axis, as well as MOE values in both major and minor axes. Even when the resin content was as low as 5%, all treatments of OSB passed the general requirement of general purpose OSB.

Mechanical Properties of Commercial Particleboard from Rubberwood (Hevea Brasiliensis) and Recycle Mix-Tropical Wood with Different Board Density

In this study, mechanical properties of commercially manufactured hybrid particleboard from mix-tropical wood and rubberwood with four different densities at 25mm thickness have been investigated. The particleboard sample cutting and testing was in accordance to EN312:2013. The density of particleboard is identified with interval of 10kg/m3 for different densities which include 660kg/m3, 670kg/m3, 680kg/m3 and 690kg/m3. Particleboards were made with the ratio of 40:60 for mix-tropical wood particle and rubberwood particle respectively. The particleboards were prepared with urea formaldehyde (UF) with E1 formulation with addition of wax and hardener. Increment of 10kg/m3 density for each particleboard led to increase in internal bonding (IB), bending testing include modulus of rupture (MOR) and modulus of elasticity (MOE), surface soundness (SS) and screw edge (SE) withdrawal. It was found that with board increment of 10kg/m3, the improvement was not statically significant except that for MOR. All panels met the minimum requirements of standard.

Sifat Fisis dan Mekanis Oriented Strand Board Hibrida Bambu Pada Berbagai Shelling Ratio (Physical and Mechanical Properties of Hybrid Bamboo Oriented Strand Board at Various Shelling Ratios)

Hybrid Bamboo Oriented Strand Boards (OSB) were produced to improve bamboo OSB's physical and mechanical properties. Shelling ratio adjustment of the strand type combination could determine the optimal physical and mechanical properties of hybrid bamboo oriented strand boards (OSB). The purpose of this study was to evaluate the physical and mechanical properties of hybrid betung and andong bamboos OSB at various shelling ratios. Steam modified strands of betung and andong bamboo were used as an outer layer and core layer, respectively. Hybrid bamboo OSBs were prepared with 0.7 g cm-3 target density and 8% phenol-formaldehyde resin content. Three layers of OSB were made with outer: core shelling ratios of 30:70, 40:60, 50:50, and 60:40. The physical and mechanical properties of the OSB were tested referring to the JIS A 5908-2003 standard. The targeted board density was achieved and the physical properties of all hybrid bamboo OSB have met the requirement of CSA O437.0 (Grade O-1) standard criteria. The parallel modulus of elasticity (MOE) and modulus of rupture (MOR) increased with increasing outer layer ratio. However, the perpendicular MOE and MOR decreased with increasing outer layer ratio. The internal bonding (IB) of the OSB with a shelling ratio of 30:70 and 40:60 met with the requirement of the CSA O437.0 (Grade O-1) standard.

Drying performance, as well as physical and flexural properties of oil palm wood dried via the super-fast drying method

Effects of incising parameters were studied relative to the drying performance and properties of super–fast dried oil palm wood. Different incising depths (1/3, 1/2, 2/3, and 100% of the total thickness) and distance (38 mm and 50 mm) were made on the oil palm wood boards prior to the super-fast drying procedure. All the boards achieved the desired moisture content after drying. Drying defects were minimal, as only two boards indicated end checks and surface checks defects. The board density ranged from 0.44 g/m3 to 0.60 g/m3, and the thickness swelling and water absorption of the boards ranged from 8.3% to 12.5% and 45% to 67%, respectively. The specific modulus of rupture and elasticty ranged from 0.35 N m3/kg mm2 to 0.77 N m3/kg mm2 and from 77.64 N m3/kg mm2 to 118.40 N m3/kg mm2, respectively. It can be concluded that the hole distances did not exert significant effect on the properties, with exception of specific modulus of elasticity. A hole depth of 1/3 mm was preferable, since the surface looked like no incision had been made and the sample had good physical and flexural properties.

Influence of Board Density on the Physical and Mechanical Properties of Bamboo Oriented Strand Lumber

The process of bamboo-oriented strand lumber (BOSL) represents one of the best opportunities for automation, property control and consistency, and high utilization of material from abundant, fast-growing, and sustainable bamboo. In this study, BOSLs were prepared, with reference to the preparation process of bamboo scrimber, by compressing and densifying constituent units under the action of moisture-heat-force and resin polymerization, and then the effects of density variation on their physical and mechanical properties were investigated. The results revealed that the modulus of rupture, modulus of elasticity, compressive strength and shear strength of BOSL with density of 0.78–1.3 g/cm3 ranged from 124.42 to 163.2 MPa, 15,455 to 21,849 MPa, 65.02 to 111.63 MPa, and 9.88 to 18.35 MPa, respectively. The preparation of BOSL with bamboo as raw material could retain the good mechanical properties of natural bamboo, and produce bamboo-based structural products with different properties by controlling the density. The high strength of BOSL with high density was primarily due to the increased volume fraction of elementary fibers, the reduced porosity, and the enhanced gluing interface. The performance of BOSL can be comparable to, or surpass that of, wood or bamboo products. This study provided necessary basic research for the engineering design and application of BOSL.

Distribution of Vascular Bundles and Physical Properties Analysis of Variety DxP Oil Palm Trunk Based on Various Zones and Trunk Heights

In an attempt to obtain a homogenous board density from the palm trunk, this research was carried out to analyze the distribution of vascular bundles and the physical properties of the oil palm trunk (moisture content, density, and specific gravity) in various zones and trunk heights. Oil palm trunk samples were used from 29 years old palm (Planted on 1991) which acquired from Aek Pancur Experimental plantation, Indonesian Oil Palm Research Institute (IOPRI). The oil palm trunk sample was cut based on the trunk zones (peripheral, central, and inner), and trunk heights (1, 2, 3, 4, 5, 6, 7 m). The observed parameters were vascular bundles, moisture content, density, and specific gravity. The results showed that the highest number of vascular bundles in the peripheral zone (73.66 vb/cm2). In addition that, the highest density and specific gravity also found in peripheral zone with an average 0,73 gram/cm3 and 0.53, whereas the highest moisture content was found in the inner zone with an average value 141%(w/w). Furthermore, the statistical analysis ((ANOVA and regression test (R2)) in this study showed that the trunk zone factor was more significant than the trunk height for all observed parameters (distribution of vascular bundles, moisture content, density and specific gravity).

Characteristics of particleboard manufactured from bamboo shoot sheaths

This study emphasizes on the physical, mechanical, and thermal properties of single-layer particleboard manufactured from bamboo shoot sheaths. Particleboards were produced through the hot-pressed process and glued together by Diphenylmethane Diisocyanate (MDI) adhesive. This is in order for producing specified densities of boards as 400-kg, 600-kg, and 800-kg per m3. The raw material was sieved into four sizes: No.1-No.4 mesh. The particleboards were used to find board density, water absorption, thickness swelling, modulus of elasticity, modulus of rupture in bending, and internal bonding according to the JIS standard. Coefficients of thermal conductivity (k) of boards were discovered by a heat flow meter in steady-state conditions. The results showed that the particleboard performed outstandingly in terms of tensile strength perpendicular to the surface (internal bonding) and low thermal conductivity. However, there were some weaknesses found from their characteristics that were high water absorption and thickness of swelling, low modulus of elasticity and modulus of rupture comparing to standard criteria. The results also indicated that bamboo shoot sheaths, the agricultural residue, can be produced as particleboard, and are appropriate for an indoor heat insulator, but further investigation is required to improve the strength and durability of the particleboard.

Sifat Fisis Dan Keunggulan Papan Semen Dari Limbah Kulit Batang Sagu

This research aimed to determine the physical properties and advantages of cement boards made from sago stem bark waste based on the test results of several parameters, according to JIS A 5908 (2003) standard. The results show that the physical properties of cement board from sago stem bark waste with the addition of the CaCl2 catalyst were good with the average value of cement board density ranged from 1.19-1.26 gr/cm³, water content 7,67-8,02%, water absorption after immersion 2 hours 6,03-7.65% and after 24-hour immersion 11,62-12,91%, respectively. The averages swelling value of board thickness after immersion 2 hours 1.62-12,91% and after immersion 24 hours 1.40-3.41%. Furthermore, sago bark waste in various positions of the tree trunk (tree base, middle, and top) can be utilized to manufacture the cement board. However, the board made from sago stem bark waste at the ground with the addition of a catalyst CaCl2 6% has the best physical properties and meets JIS A 5908 (2003) standard. Cement boards from sago stem bark waste have an excellent waterproof capability and can be used as outdoor materials.