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The kapok (Ceibapentandra (L.) Gaertn) seed fibre is unicellular with length up to 35 mm, however, it is covered by a hydrophobic waxy layer that limits its application in paper production. In this study, the effect of various pulping methods namely mechanical, chemi-mechanical, semichemical and chemical pulping on kapok fibre properties was investigated. Each kapok pulp was then blended with the secondary fibre recovered from kraftliner board for handsheet making to examine their reinforcing ability on strength properties. The results showed that kapok mechanical pulps (with and without dewaxing (5% (v/v) diluted detergent) and chemimechanical pulp were unable to improve the strength properties of the handsheet. Kapok pulps chemically treated with 18–25% of sodium hydroxide gave a better effect on handsheet strength properties whilst fibre treated with 20% sodium hydroxide showing the highest increment. Although the reinforcing effect of the 4% native cooked starch was slightly higher than that of the 10% kapok pulp blended in recycled paper, the recycling potential of the latter was better as all strength properties retained unchanged after recycling. The findings indicated that kapok chemical pulp is a promising reinforcing fibre source with superior recycling potential.

The conventional wood-based composites contain an unreacted free formaldehyde, which causes a cancerous effect on humans. To overcome this problem, citric-acid-modified corn and oil palm starches are proposed as ecobinders for wood-based composites in this study. Experimental rubber-wood panels were made using the ecobinders. The panels were subjected to FT-IR, TGA, DSC, and X-ray diffraction analyses, and then their modulus of elasticity, modulus of rupture, bond strength, water absorption, and thickness swelling were determined experimentally. The results obtained are shown in figures and tables.

Studies of bio-nanocomposites using sustainable green materials from biomass waste are presently gain the attention worldwide. This study investigated the properties of bio-nanocomposite films from polyvinyl alcohol incorporated with 1%, 3%, and 5% via solvent casting method using various types of oil palm trunk cellulose nanocrystals isolated using various types of treatment. The produced bio-nanocomposite films were characterized for their mechanical behavior, morphological properties, thermal properties, and functionality groups and the effect of adding the oil palm trunk cellulose nanocrystals into the bio-nanocomposites films were then evaluated. The results showed that the mechanical properties and thermal stabilities of the bio-nanocomposite films increased with the incorporation of cellulose nanocrystals. The bio-nanocomposite films added with 3% cellulose nanocrystals with pre-hydrolysis treatment showed better mechanical and thermal properties and hence have a great potential to be utilized as a raw material or reinforcement in the packaging industries.

Sap from the trunk of oil palm (Elaeis guineensis) was processed into syrup in this study. Physicochemical properties of syrups produced from the sap of freshly cut oil palm trunks (OPT0syrup) and sap of trunks stored for 60 days (OPT60syrup) at ambient temperature were compared to nipa palm syrup (Nsyrup), maple syrup (Msyrup), and two commercial glucose syrups (G1syrup and G2syrup). The total soluble solids for the syrups (OPT0sy, OPT60sy, Nsy, Msy, G1sy and G2sy) were in the range of 66 to 82 ˚Brix. The sugar analysis indicated that glucose was the main sugar for OPT0sy and OPT60sy as 367 and 300 mg/g, respectively, whereby sucrose was the foremost sugar for Nsy and Msy. The colour of the syrups was ranked from the darkest to the lightest; OPT60syrup > OPT0syrup > Msyrup > Nsyrup > G1syrup > G2syrup. OPT0syrup and OPT60syrup achieved reducing capacity of 825 and 886 mg GAE/100 g, respectively, significantly higher than other syrups. The free radical scavenging activities of OPT0syrup and OPT60syrup were 74% and 70%, respectively. In conclusion, the oil palm trunk syrup has similar physicochemical properties with the commercial syrups, and it has the potential to be an alternative to the commercial sweeteners with added nutritional benefits.

Photon absorption parameters such as mass attenuation coefficients ( $${\mu }_{\mathrm{m}}$$ ), molar extinction coefficients ( $$\varepsilon$$ ), total molecular ( $${\sigma }_{\mathrm{t},\mathrm{m}}$$ ), atomic ( $${\sigma }_{\mathrm{t},\mathrm{a}}$$ ) and electronic ( $${\sigma }_{\mathrm{t},\mathrm{el}}$$ ) cross sections, half-value layers $$({X}_{1/2})$$ , tenth-value layers ( $${X}_{1/10}$$ ), mean free paths $$(\lambda )$$ , effective atomic numbers ( $${Z}_{\mathrm{eff}}$$ ), and effective electron densities ( $${N}_{\mathrm{el}}$$ ) were estimated for defatted soy flour (DSF), soy protein concentrate (SPC), and soy protein isolate (SPI)-based Rhizophora spp. particleboard composites substituted with 10 wt% sodium hydroxide (NaOH) and 0, 5, 10, and 15 wt% itaconic acid polyamidoamine-epichlorohydrin (IA-PAE) adhesives. Elemental composition was assessed using ultrahigh-resolution field emission scanning electron microscopy-energy dispersive X-ray spectrometry (UHR-FESEM-EDX). The interaction parameters were evaluated for $${\mathrm{K}}_{\mathrm{\alpha }1}$$ photons at 16.59, 17.46, 21.21, and 25.26 keV, employing a low-energy germanium (LEGe) detector system and an 241Am $$\gamma$$ -ray source. X-ray diffraction characterization revealed an amorphous phase in the developed particleboard composites. Samples DSF15′, SPC15′, and SPI15′ exhibited the highest values of $${\mu }_{\mathrm{m}}$$ , $$\varepsilon$$ , $${\sigma }_{\mathrm{t},\mathrm{m}}$$ , $${Z}_{\mathrm{eff}}$$ , and $${N}_{\mathrm{el}}$$ among all of the studied particleboard samples, within the range of measured photon energies. In addition, all of the modified samples exhibited lower $${X}_{1/2}$$ , $${X}_{1/10}$$ , $$\lambda$$ , $${\sigma }_{\mathrm{t},\mathrm{a}}$$ , and $${\sigma }_{\mathrm{t},\mathrm{el}}$$ than the unmodified samples, with DSF-, SPC-, and SPI/NaOH/Rhizophora spp./IA-PAE (15 wt%), indicating insignificant changes. The current results of the particleboard samples’ analysis can be useful for medical radiation applications and shielding research.

Some researchers formerly provided the mechanical, physical, and attenuation properties of the fabricated Eremurus–Rhizophora spp. particleboard phantom. In this study, the percentage depth dose (PDD) and the half value layer (HVL) of fabricated Eremurus–Rhizophora spp. particleboard phantom were determined and compared with those of Perspex and water phantoms, with the same standard phantom size (30 cm × 30 cm × 30 cm) in the diagnostic energy range using TLD 100H. In addition, the energy range of X-ray was in diagnostic range of energy. The results indicated that the PDD and HVL of the fabricated Eremurus–Rhizophora spp. particleboard phantom were close to those of the Perspex phantom. Likewise, the PDD and HVL of the fabricated Eremurus–Rhizophora spp. particleboard phantom were found in good agreement with those of water phantom. According to the results of this study, the fabricated Eremurus–Rhizophora spp. particleboard phantom can be used as medical phantoms.

Particleboard from renewal agricultural residues or waste offers a significant effect toward ecological problem. However, hygroscopic nature of waste material contributes to a lower dimensional stability and lower strength properties in comparison to conventional particleboard. Therefore, the objective of this study was to convert oil palm waste, namely oil palm trunk, into particleboard with the addition of polylactic acid (PLA), a type of biodegradable thermoplastic, as a natural binder. Particleboard of oil palm trunk made with a target density of 0.8 g/cm3, at a pressing temperature of 180 °C, a pressing time of 20 min, and a pressure of 5 MPa was added with 10% of PLA. The PLA was added into different thickness particleboards, namely 5 mm, 10 mm, and 15 mm. The mechanical and physical properties of particleboards with the addition of PLA in comparison to binderless particleboards made from oil palm trunk were then evaluated. Thus, thermal degradation, spectroscopic characterization, crystallinity properties, and morphological properties of such types of boards were also examined. The mechanical properties, such as modulus of rupture and internal bond strength, and physical properties, such as thickness swelling and water absorption, had significantly improved with the addition of PLA compared to binderless particleboard. Particleboard with the addition of PLA exhibited satisfactory mechanical properties based on Japanese Industrial Standard for Particleboard Type 8. The thermal stability, spectroscopic characterization, crystallinity, and morphological results indicated that the addition of PLA improved the basic properties of the particleboards made of oil palm trunk.

The aim of this study was to determine the suitability of tannin-added Rhizophora spp. particleboards as phantom materials in the application of low- and high-energy photons. The tannin-added Rhizophora spp. particleboards and density plug phantoms were created with a target density of 1.0 g/cm3. The elemental composition and effective atomic number of the particleboards were measured using energy dispersive X-ray analysis. The mass attenuation coefficient of the particleboards for low-energy photons were measured using the attenuation of X-ray fluorescence. The mass attenuation coefficients of high-energy photons were measured using the attenuation of 137Cs and 60Co gamma energies. The results were compared to the calculated value of water using XCOM calculations. The results showed that the effective atomic number and mass attenuation coefficients of tannin-added Rhizophora spp. particleboards were similar to those of water, indicating the suitability of tannin-added Rhizophora spp. particleboards as phantom materials for low- and high-energy photons.

The structures of the title Indeno-imidazole compounds, have been determined by FTIR, NMR, mass and single crystal X-ray diffraction. 3a,8a-Dihydroxy-1-phenyl-1,3,3a,8a-tetrahydro-indeno[1,2-d]imidazole-2,8-dione (1) crystallizes in the monoclinic, space group P2 1/c with a = 12.0913(7) A, b = 5.7204(3) A, c = 19.8168(11) A, α= 90.00 ∘, β= 103.6650(10) ∘, γ= 90.00 ∘, V = 1331.87(13) A 3, Z = 4; while 3a,8a-Dihydroxy-1-phenyl-2-thioxo-2,3,3a,8a-tetrahydro-1H-indeno[1,2-d]imidazol-8-one (2) crystallizes in the monoclinic, space group P2 1/c with a = 11.0101(5) A, b = 6.8421(3) A, c = 21.1243(9) A, α= 90.00 ∘, β= 110.771(2) ∘, γ= 90.00 ∘, V = 1487.91(11) A 3, Z = 4. Solid-state crystal structures of compounds 1 and 2 are presented here in terms of crystal engineering and supramolecular chemistry. Replacement of oxygen atom of compound 1 by sulfur atom in compound 2 forced compound 2 to hold water molecules and formed the hydrated form.

This research aimed at investigating the effect of epoxy resin and flame retardant additives on oil palm trunk particleboard. The oil palm trunk was used as a raw material with epoxy resin as a binder, which was synthesized by a reaction of epichlorohydrin and phenolphthalein, while aluminium hydroxide and magnesium hydroxide were used as flame retardant additives to manufacture particleboards. Four different types of particleboards were produced, control board, board with 10% epoxy resin, board with 10% epoxy resin and 6% aluminium hydroxide and board with 10% epoxy resin and 6% magnesium hydroxide, based on a target density of $$0.80~\hbox {g}~\hbox {cm}^{-3}$$, at a temperature of $$180^{\circ }\hbox {C}$$, a pressure of 5 MPa and a pressing time of 20 min. The mechanical, physical, functional group, spectroscopic, morphological and elemental analysis properties were determined in comparison with control particleboard. Thermal degradation and flame retardant analyses were also carried out to analyse the thermal properties of particleboards. The results indicated that particleboard bonded with epoxy resin and flame retardant additives had improved mechanical, physical, thermal and flame retardant properties compared to control oil palm trunk particleboard. Overall results showed that epoxy resin as a binder and aluminium hydroxide and magnesium hydroxide as additives have the potential to be incorporated into the particleboard to improve flame retardant properties.

Malaysia is one of the biggest producers of palm oil in the world but the oil palm wood is considered as waste after final harvesting. A huge and inexpensive availability of oil palm trunk (OPT) can be a sustainable source of alternative wood for various structural applications, if it can be utilized. The objective of this work was to prepare a steamed treated compressed OPT lumber and evaluate the physical, chemical and biological properties of modified wood. In this technique OPT samples were steamed at temperature 130 °C for 2 h before being compressed at high temperature. Wettability of the steam compressed OPT was analysed by contact angle method and observed it was reduced as compared to simply compressed OPT. Samples were exposed to outdoor conditions to evaluate their resistance against biological deterioration. Microscope and X-ray diffraction analyses of the samples were also carried out. Steamed compressed OPTs exhibited improved resistance against biodegradation probably due to the increase of extractives in it, as compared to simply compressed OPTs. It seems that steaming in combination of compressing at high temperature would enhance the properties of OPTs.

The existing approach of response surface methodology was extended to study the adsorption of methyl orange dye on optimized Acacia mangium wood-based activated carbon with a Brunauer, Emmett and Teller surface area of 1,767 m2/g. The experiments were carried out in a batch system, and the optimal condition was determined by means of the face-centered central composite design of response surface methodology. The effect of activated carbon dose, temperature and contact time on the adsorption capacity and percentage removal of methyl orange dye molecules were optimized. The experimental results indicated that the optimal conditions for the maximum adsorption capacity were 0.515 g/L, 55.0 °C and 24 h for adsorbent dose, temperature and contact time, respectively. Under these conditions, the maximum adsorption capacity and percentage removal were found to be 181 mg/g and 90.5 %, respectively. At optimized conditions of methyl orange dye removal, studies of the kinetic and thermodynamic behavior of adsorption revealed that it followed the pseudo-second-order rate model and was spontaneously endothermic in nature.

A study on the preparation of activated carbon from Acacia mangium wood was conducted, and the operating factors, such as activating agent concentration, activation temperature and activation time, were optimized using response surface methodology. In order to determine the effects of the operating factors namely H3PO4 concentration (6.48–48.5 %), activation temperature (364–1,036 °C) and activation time (19–146 min) on the characteristics of activated carbon, a three-level rotatable central composite design was used. The second-order mathematical model was proposed by regression analysis of the experimental data gathered from 20 batch runs. The optimum H3PO4 concentration, activation temperature and activation time were found to be 40 %, 900 °C and 45 min, respectively. At optimum conditions of the operating factors, the percent yield and surface area were 20.3 % and 1,767 m2/g, respectively. The activated carbon was found to be largely composed of mesopores. About 95 % of the total surface area was attributed to mesopores.

The objective of the study was to evaluate some properties of experimental binderless particleboards produced from various processing parameters. Three different temperatures (160, 180, 200 °C), two different hot pressing times (15, 20 min) and two different pressures (5, 10 MPa) were applied in manufacturing the binderless particleboard. Three replications of each of the 12 different types of boards with a target density of 0.60 g cm−3 were produced. The thickness swelling, dimensional changes associated with changes in relative humidity, bending strength, internal bonding strength, and soil burial decay test were evaluated. Increase of temperature, duration of hot pressing and pressure increased the properties of specimens. Thickness swelling nearly met the requirement of European Standard for use in humid condition. Some of the specimens showed promising mechanical properties and met the requirement of European Standard.

Oil palm industries produce an enormous quantity of lignocellulosic biomass; in the form of large leaves of palm tree, pruned fronds (OPF) and oil palm trunks (OPT) at the plantations site. Besides this, the processing of fresh fruit bunches in the oil mills generates empty fruit bunches (EFB), shells, kernel cake and mesocarp fibers. The proper management of this burgeoning waste and its disposal is an ardent task and creates environmental hazards. In order to deal with the biomass residues, the urgent need is that it should be transformed into resources with industrial utility. As the economic development has resulted in the significant increased demand for paper, the industry is looking for eccentric sources to fulfill the requirement. The pulp and paper industry preferred use of coniferous and deciduous trees for papermaking because their cellulose fibers in the pulp make durable paper. With improvements in pulp processing technology, fibers of almost any non-wood of plants species like bamboo, cereal straw, sugarcane, flax, hemp and jute can be used for paper pulp. Substituting this lignocellulosic material can reduce the burden on forest while supporting the natural biodiversity. The present review deals with the possibilities of using oil palm biomass as a raw material for pulp and papermaking, as this would ameliorate its waste management problem. The potential of oil palm biomass and the challenges regarding its use in papermaking are discussed. The use of oil palm biomass will apparently prove that the oil palm industry is ecofriendly in every aspect of its activities and aid in sustainability of forest ecosystem.

5-Phenylamino-3-phenylimino-3H[1, 2]dithiole-4-carboxylic acid ethyl ester, C18H16N2O2S2, (I), has been synthesized and the structure has been solved by X–ray diffraction. The crystals are triclinic, space group $$ P\bar{1} $$ , with a = 5.7127(2) A, b = 12.1757(5) A, c = 14.0734(5) A, α = 112.1217(16)°, β = 97.786(2)°, γ = 100.694(2)°, Mr = 356.45, V = 868.11(6) A3, Z = 2 and R = 0.0373. In the title compound there is an intramolecular N–H···O hydrogen bond. The crystal structure is stabilized only by weak C–H···π and π···π interactions as well as by van der Waals forces. The geometry of the isolated molecule was optimized by ab initio quantum mechanical calculations, employing both molecular orbital Hartree-Fock (HF) and density functional theory (DFT) methods. In the DFT calculation the minimum energy was achieved for a conformation very similar to that of the solid-state molecule. The crystal packing of 3-phenylamino-5-phenylimino-[1, 2]dithiolane-4-carboxylic acid ethyl ester is stabilized only by weak interactions. Ab nitio calculations for the free molecule show that the crystal packing has little influence on the molecular conformation.

2-Chloro-1,3-dioxo-2,3-dihydro-1H-inden-2-yl acetate, C11H7ClO4 (Fig. 1), has been synthesized and the structure has been solved by IR and X-ray diffraction studies. The crystals are triclinic, space group P $$ \bar{1} $$ , with a = 7.62060(10) A, b = 11.5944(2) A, c = 13.0753(3) A, α = 97.2820(10)°, β = 101.5740(10)°, γ = 101.7930(10)°, Mr = 238.62, V = 1090.82(3) A3, Z = 4 and R = 0.0557. In the title compound there are two molecules in the asymmetric unit. The molecules are linked via weak C–H···O hydrogen bonds forming R 4 4 (28) rings. The intermolecular interactions were analysed by means of the fingerprint plots derived from the Hirshfeld surfaces. The fingerprint plots evidenced subtle differences in the intermolecular contacts for the two independent molecules. The structure of 2-chloro-1,3-dioxo-2,3-dihydro-1H-inden-2-yl acetate has two molecules in the asymmetric unit. The crystal packing is stabilized only by weak interactions. Ab nitio calculations for the free molecule show that the crystal packing has little influence on the molecular conformation.

Meranti wood, an inexpensive material, has been utilized as an adsorbent for the removal of cadmium (II) from aqueous solutions. Various physico-chemical parameters such as equilibrium contact time, solution pH, initial metal ion concentration, and adsorbent dosage level were studied. Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherms were used to analyze the equilibrium data at different temperatures. The experimental data fitted well with the Langmuir adsorption isotherm, indicating the monolayer adsorption of the cadmium (II). The monolayer adsorption capacity of meranti wood for cadmium (II) was found to be 175.43, 163.93 and 153.84 mg/g at 30, 40, and 50°C, respectively. The thermodynamics of cadmium (II) adsorption on meranti wood indicates its spontaneous and exothermic nature. Kinetic studies showed that the adsorption followed a pseudo-second-order kinetic model. The results indicated that the meranti wood could be an alternative for more costly adsorbents used for cadmium (II) removal.

Cyclohexyl N-phenylcarbamate, C13H17NO2 (I), which is a useful target for biotransformations by fungi, has been synthesized and the structure has been solved by X-ray diffraction. The crystals are triclinic, space group P $$ \bar{1} $$ , with a = 5.2581 (2) A, b = 9.5080 (3) A, c = 12.6165 (4) A, α = 70.544 (2)°, β = 89.075 (2)°, γ = 80.447 (2)°, M r = 219.28, V = 585.96 (3) A3, Z = 2 and R = 0.065. In the title compound the phenyl ring makes a dihedral angle of 30.68(7)° with the carbamate group The molecules are linked into infinite chains via N–H···O hydrogen bonds along the a axis. These hydrogen-bonded chains are further linked by weaker C–H···π interactions. Quantum-mechanical ab initio calculations for the free molecule reproduce well the observed bond lengths and valency angles but show that the crystal packing might be responsible for the rotation of the phenyl ring out of the carbamate plane in the solid state conformation. In cyclohexyl N-phenylcarbamate the molecules are linked into infinite chains via N–H...O hydrogen bonds along the a axis. Ab initio calculations for the free molecule show that the crystal packing might be responsible for the rotation of the phenyl ring out of the carbamate plane in the solid state conformation.

Biopulping can be an alternative to the traditional methods of pulping. Biopulping use fungi that are known to be able to degrade wood as well as lignin constituent of wood. Amongst these white rot fungi are the most proficient biodegrader. The fungus is non sporulating and is a selective lignin degrader. It colonizes either on living or dead wood and decomposes all wood polymers including lignin and extractives making it to be extremely potential to be used in biopulping. The process of biopulping reduces the utilization of chemical in pulping industry and help in decreasing the environmental hazard caused by normal pulping. The present review deals with diverse aspects of biopulping and their ecological as well as economic significances.

The antioxidant activities, total phenols and antifungal activities of 35 extracts samples from 15 species of Malaysian timber were investigated. The methanol extracts from Mangifera indica heartwood were found to have superior antioxidant activity with an EC50 value of 4.71±0.89 μg/ml. Antioxidant activities correlated with total phenols contents. The methanol extracts from Neobalanocarpus heimii bark and Cinnamomum porrectum heartwood showed moderate antifungal activity against a brown-rot fungus, Gloeophyllum trabeum. The methanol extracts from Neobalanocarpus heimii bark and Endospermum malaccense inner wood showed the highest antifungal activity against a white-rot fungus, Pycnoporus sanguineus, at a minimum effective amount of 100 μg. The activities of these extracts were equal to the activity of the positive control, glycyrrhizic acid dipotassium salt, suggesting that they have great potential as a source of fungistats.

In this paper the title compound 3,5,4′-trihydroxy-6,7-dimethoxy-flavone (Eupalitin) has been isolated from Asparagus falcatus and characterized by UV, IR, NMR, mass spectra and X-ray single crystal diffraction. The 3,5,4′-trihydroxy-6,7-dimethoxy-flavone crystallizes in a monoclinic space group P21/n with a = 6.2527(2), b = 17.2821(6), c = 13.5476(5) A, β = 100.274(2)° and Z = 4, β = 100.274(2)° and V = 1440.48(9) A3. The crystal structure are stabilized by intra- and intermolecular O–H···O hydrogen bonds. Molecules pack into infinite zigzag-like layers with these hydrogen bonds. The title compound 3,5,4′-trihydroxy-6,7-dimethoxy-flavone (Eupalitin) has been isolated from Asparagus falcatus and characterized by UV, IR, NMR, mass spectra and X-ray single crystal diffraction.

In this study, the properties of laminated veneer lumber (LVL) made from oil palm trunks (OPT) were evaluated in comparison with rubberwood using cold setting adhesives, namely, emulsion polymeric isocyanate (EPI) and polyvinyl acetate (PVAc). The evaluations were based on either dry or after cold water, hot water and cyclic pre-treatment. The density of the OPT LVL was slightly higher than that of solid OPT. Thickness swelling and water absorption of OPT LVL were greater than of rubberwood LVL. Pre-treatment increased the water absorption and thickness swelling. The OPT LVL bonded with EPI without toluene showed greater water absorption and thickness swelling than EPI with toluene. Pre-treatment significantly reduced the tensile strength of OPT LVL. The OPT LVL bonded with EPI without toluene showed higher tensile shear strength, but a greater reduction of tensile shear strength after pre-treatment, than the OPT LVL bonded with EPI and toluene. The PVAc adhesive had greater wettability than the EPI. The EPI without toluene showed a lower contact angle than the EPI with toluene. The loose side of the OPT veneer was found to have greater wettability than the tight side.

Oil palm is the largest and most important plantation crop in Malaysia. The oil palm generally lasts for 25–30 years before the next replantation is done. Substantial amount of biomass in the form of palm trunk results from plantation cycle. This resource is simply left on the ground to decay and is not used as raw material to manufacture any kind of value-added products. The objective of this study was to investigate the possibility of manufacturing plywood from oil palm trunks and to evaluate some of the finishing properties of such experimental panels in comparison to those from Shorea sp as control samples. Three-ply plywood samples were produced from 5 mm thick veneers of oil palm using urea formaldehyde adhesive. Three types of chemicals, namely nitrocellulose, pre-catalyzed lacquer and polyurethane were used to finish experimental panels. The surface finished with nitrocellulose had the lowest contact angle on raw surface of oil palm plywood and wood. The average cross cut tape index of oil palm plywood was comparable to Shorea sp. All finishing materials of oil palm plywood produced impact rating of 4 except for surface finished with nitrocellulose while finishing on wood indicated an impact rating of 3. Oil palm plywood had higher weight loss compared to Shorea sp. Based on results from contact angle, cross cut tape index, impact rate test, weathering, and soil burial test methods it appears that the samples showed acceptable finishing properties comparable to those of solid wood.

has been studied by a successive extraction of the wood with a series of solvents with increasing polarity, followed by GC, GC/MS and DC studies of the fractions obtained. The study of the extractives of sound and affected wood with respect to yield and composition cannot explain the influence of the heartrot fungi on wood components in detail. Differences mainly have been found in the more polar fractions (acetone/water and ethanol/water, respectively). The content of lipophilic extractive constituents is with about 0.6–0.7% rather low and does not differ between sound and affected heartwood. The composition of the lipophilic extractives is not very different either.

The formation of caoutchouc in teak sapwood and heartwood was examined in an increment borer core using light microscopy after staining with osmium tetroxide. The distribution of the polyisoprenoid in untreated and extracted heartwood, its influence on surface chemistry, contact angle with water and formation of radicals before and after irradiation with sunlight, and also on decay resistance were determined. Caoutchouc was not observed in the cambial zone and outer sapwood, but occurred from the middle of sapwood as black globule. In sapwood, if available, it was mainly found in the lumen of parenchyma. In heartwood the globule were also detected in fibers and vessel elements. They usually fused into one big or irregular formed structures. SEM of untreated heartwood cuttings showed that lumen of all cell types and also the cut-surfaces were covered with extraneous materials. Extraction with acetone which removed extractives except caoutchouc did not change the surface morphology markedly. Residual caoutchouc still covered cell lumen and cut-surfaces. Successive extraction with acetone and chloroform removed extraneous materials, and lumen surfaces and cut-surfaces became clear. It revealed that caoutchouc occurred also in cell walls. The XPS spectrum of untreated teak heartwood showed a rather high C1, a moderate C2 and a low C3 peak area. After acetone extraction the C1 peak area increased slightly but the C2 and C3 area decreased. Successive extraction with acetone and chloroform caused a significant decrease of C1, but an increase of both C2 and C3 values. Untreated teak heartwood cuttings showed a high contact angle with water, indicating hydrophobic properties. Extraction with acetone increased contact angle slightly. This is explained by removal of polar compounds and redistribution and enrichment of the apolar caoutchouc on the surface. Successive extraction with acetone and chloroform removed all extractives and contact angle was significantly reduced. The ratio of ESR relative signal intensities of free radicals in untreated specimens, acetone extracted and acetonechloroform extracted specimens which were irradiated and non-irradiated showed the highest values for acetone extracted ones, followed by untreated and acetone-chloroform treated specimens. Reconstituted panels made from ethanol extracted teak heartwood meal were decay susceptible. Specimens made from wood meal successively extracted with ethanol and chloroform showed slightly less resistance that specimens made from ethanol extracted ones. The high decay resistance of untreated teak heartwood is postulated due to a synergetic effect of decay active ethanol extracts and non-active caoutchouc.