Search

This article aims to shed the light about the important geographical factors that influence the localization of Peninsular Malaysia timber mills to further understand the employment of sustainable timber industry practice as well as proposing the general raw materials’ supply chain in Peninsular Malaysia timber industry. This study is performed by using secondary data from Moderate Resolution Imaging Spectroradiometer land cover V6 MCD12Q1 data of NASA LPDAAC Collections from US Geological Survey and Malaysia Timber Industry Board for geographical factors as well as primary, secondary and tertiary timber mills’ information, respectively. The analysis from negative binomial regression analysis reveals that the geographical location for logs’ storage and transportation is affecting the primary timber mills’ localization, while a number of primary mills and secondary mills are affecting by the locations of raw materials’ supplies. This study gives an impactful insight for the Peninsular Malaysia timber industry in creating the timber industry’s policy regarding the roles of timber mills as the linkages in coordinating a sustainable timber industry.

Forests represent a substantial part of global socio-economy platforms. As the wood-based industry contributes large revenue to Malaysia’s economy, the readiness of Peninsular Malaysia towards sustainable wood-based industry was measured based on the different types of wood processing industries and Sustainable Forest Management (SFM) practice. Surveys (1,447) from all operating timber mills according to their raw materials type for wood products processing in Peninsular Malaysia were analyzed using multiple correspondence analysis (MCA). Results showed that the sustainable practice in wood industry by SFM practitioners and non-practitioners were similar. All industries are using outdated technologies and consume local raw materials in producing wood products. The furniture industry is largely aware of SFM and consumes the least amount of logs to produce furniture.

The empty fruit bunch (EFB) and kenaf polypropylene (PP) nonwoven composites in this study were prepared via needle punching nonwoven process followed by compression moulding. As compare to the fine kenaf fibre, the thick and rough fibre such as EFB is uncommon in the nonwoven process although it could be a cheap alternative material. To establish EFB as a new raw material in needle punching nonwoven composite, the effect of type of fibre, fibre content, fabric direction and fabric weight on mechanical properties of polypropylene nonwoven preform and composite was studied. Statistical Analysis of Variance (ANOVA) has been used to analyse the effects of the parameter to the preform and composite properties. The punching density, fabric weight and natural fibre content were set at 0, 150 and 300 punches/cm2; 300, 400 and 700 g/m2; 40, 50 and 60%, respectively. This study showed that type of fibre has significant influence on the tensile strength of the nonwoven preform especially at 60% fibre content as compare to the nonwoven composite. The fibre content and fabric direction were also the main factors affecting the tensile strength and the tensile elongation of the nonwoven preform. It was proven that EFB has great potential applications as nonwoven fabric and alternative reinforcement material in nonwoven composites.

This study evaluated a new method of producing phenol–urea–formaldehyde (PUF) adhesives formulated differently under actual “in-situ” resin synthesis conditions. This was carried out by co-polymerizing urea formaldehyde (UF) resin with phenol–formaldehyde resin in the core layer of low molecular weight (LMW) phenol–formaldehyde (PF) resin treated Elaeis palm trunk veneers during the gluing process of Elaeis palm plywood. Matrix assisted laser desorption Ionization time of flight (MALDI-TOF) mass spectrometry (MS) illustrated and confirmed a series number of the phenol–urea co-condensates repeating unit in the prepared PUF resins which corroborated well with its mechanical properties (modulus of elasticity and modulus of rupture), bonding quality (dry test and weather boil proof or WBP test) and physical properties. A series of PF, UF and PUF resins oligomers forming repeating units up to 1833 Da were identified. Besides that, the solid state 13 Carbon nuclear magnetic resonance (NMR) interpretation identified that the signal at 44–45 ppm and 54–55 ppm corresponding to methylene bridges were co-condensated in between phenol and urea in the PUF resin system. The 13 C NMR investigation showed that the synthesis process of PUF resin contained no free formaldehyde elements. Furthermore, the proportion of urea and methylolureas in the mixture to synthesis PUF resin were sufficient and incorporated well into the formulation by reacting with LMWPF units to form co-condensed methylene bridges. This study showed a new and useful method to synthesize PUF resin during the gluing process of manufactured Elaeis palm plywood which can also enhance the performance of Elaeis palm plywood panels for structural instead of utility grade applications.

The possibility of manufacturing rubberwood and kenaf (Hibiscus cannabinus L.) stem medium density fibreboard (MDF) panels at different pressure and resin content were investigated. The effect of mechanisms of interacted independent variables (resin content and pressure) on MDF properties was analyzed. The board performance was evaluated by measuring internal bond (IB) strength, modulus of rupture (MOR), modulus of elasticity (MOE), water absorption (WA) and thickness swell (TS). The test results were statistically analyzed by using response surface method (RSM) to determine the significant independent variables that influenced MDF properties. A mathematical simulation or response surface models were developed to predict the MDF properties (MOR, MOE, IB, WA and TS). The obtained results showed that MDF density and all interactions between the experimental variables were significant factors that influenced the mechanical properties of MDF. At 8 bar and 14 % resin content, the MDF recorded WA of 83.12 % and TS of 20.2 %. It can be inferred that two parameters (resin content and pressure) had positive effect on physical and mechanical properties of MDF. We concluded that resin content show more significant effects on MDF manufacturing as compared to pressure parameters.

This research was conducted to study the feasibility of producing medium density fibreboard (MDF) from 4-year old rubberwood clone RRIM 2020. The 4-year old rubberwood is obtained from different planting densities, which is 500, 1000, 1500 and 2000 trees/ha and were processed to produce MDF. The MDF is analyzed in term of its mechanical properties (static bending and densities to comply with JIS A 5905-2006 Standard (Type 30, MOR > 30.0 MPa and MOE > 2500 MPa and Type 25, MOR > 25.0 - 30.0 MPa and MOE > 2000 - 2500 MPa). MDF made from 25 year trees clone, PB260 which come from the same clone was used as a control. The results showed that the PB260 and the 4-year old rubberwood clone with planting densities of 500 trees/ha satisfied the requirement of Type 30, and the remaining passed at Type 25. It shows that it is feasible to produce an MDF using the 4-year old rubberwood clone.

The aim of this study was to develop cellulose nanofibers with hydrophobic surface characteristics using chemical modification. Kenaf fibers were modified using acetic anhydride and cellulose nanofibers were isolated from the acetylated kenaf using mechanical isolation methods. Fourier transform infrared spectroscopy (FTIR) indicated acetylation of the hydroxyl groups of cellulose. The study of the dispersion demonstrated that acetylated cellulose nanofibers formed stable, well-dispersed suspensions in both acetone and ethanol. The contact angle measurements showed that the surface characteristics of nanofibers were changed from hydrophilic to more hydrophobic when acetylated. The microscopy study showed that the acetylation caused a swelling of the kenaf fiber cell wall and that the diameters of isolated nanofibers were between 5 and 50 nm. X-ray analysis showed that the acetylation process reduced the crystallinity of the fibers, whereas mechanical isolation increased it. The method used provides a novel processing route for producing cellulose nanofibers with hydrophobic surfaces.

Totally chlorine free (TCF) and elemental chlorine free (ECF) single and multistage sequences were used to bleach whole stem kenaf pulp. The results indicated that in contrast to unbleached kraft wood pulps, kraft kenaf pulps can be easily bleached to a brightness of 91.4% using a four-stage TCF [Q1(PO)Q2P] bleaching sequence. The ECF bleaching pulps had slightly higher selectivity and yield than those of the TCF bleached pulps. The strength properties of the TCF [Q1(PO)Q2P] and ECF (D1ED2EP) bleached pulps were comparable, with the exception of tear index and tensile index, which were slightly higher and lower for TCF pulps, respectively.

The present study was focused on the effect of chitosan, a linear amino-polysaccharide, on the properties of handsheets made from bleached kenaf kraft pulp. Chitosan was incorporated into the sheets by three distinct techniques, equilibrium adsorption (pH 5), precipitation (pH 10), and spray application. The chitosan dosages tested were 0.5%, 1%, 1.5%, and 2% based on oven dry pulp. Chitosan was found to increase the dry-strength properties of paper such as tear, burst, and tensile index, but its effectiveness was strongly dependent on the method of addition. Spray application gives superior strength properties, followed by equilibrium adsorption. Chitosan is less effective under alkaline conditions. The results showed that chitosan addition improved the mechanical properties of sheets, but the rate of increase in strength properties was higher from 0% to 0.5% compared to 1% to 1.5% regardless of the treatment techniques.

In this study, an attempt is made to understand the chemical and morphological characteristics of Malaysian cultivated kenaf fractions (bast, core, and whole stem). Results based on morphologyand chemical analysis indicate that bast and core fiber fractions in the kenaf are significantly different, although the chemical composition of kenaf is quite similar to the woody mass. In the case of whole stem fibers, it is concluded that the effective length of fibers from the whole stem is reasonably good for the purpose of making printing papers.

The present paper studies the effect of chitosan, cationic starch and polyvinyl alcohol (PVA) as sizing agents to enhance surface properties of kenaf paper. The polymers were incorporated into the sheets by spray application. The results clearly showed that the addition of chitosan to a sheet formed from beaten fibres had excellent improvement in surface properties, compared to the effect of other additives. Sizing quality of cationic starch fairly matched with the sizing quality of chitosan, however, it was able to reduce the water absorption potential of paper more than chitosan at a same concentration. In most other properties, particularly the most important property for printing papers, surface smoothness, chitosan-sized papers are superior to the paper sized with cationic starch or PVA.

Kenaf and empty fruit bunch (EFB) fibre which are the important natural fibres in Malaysia were studied as nonwoven polymer composites. The effect of fibre loading on kenaf polypropylene and EFB polypropylene nonwoven composite was studied at different mixture ratio. Kenaf polypropylene nonwoven composite (KPNC) and EFB polypropylene nonwoven composite (EPNC) were prepared by carding and needle-punching techniques, followed by a compression moulding at 6 mm thickness. This study was conducted to identify the optimum fibre loading of nonwoven polypropylene composite and their effect on the mechanical strength. The study was designed at 40%, 50%, 60% and 70% of fibre content in nonwoven mat and composite. The tensile strength, flexural strength and compression strength were tested to evaluate the composite mechanical properties. It was found that the mechanical properties for both kenaf and EFB nonwoven composites were influenced by the fibre content. KPNC showed higher mechanical strength than EPNC. The highest flexural strength was obtained at 60% KPNC and the lowest value was showed by 40% EPNC. The tensile and flexural strength for both KPNC and EPNC decreased after the fibre loading of 60%.

In this study, the fiber morphology and chemical constituents of a 4-year-old rubber tree (Hevea brasiliensis Muell. Arg.) from the RRIM 2000 clone series were evaluated. The effects of planting density on the fiber morphology and chemical compositions of the clone of rubber wood were also considered. It is clear that the fibers of the rubber wood samples grown under higher planting density were thicker, with a wider lumen diameter than those grown under lower planting density. There were significant interactions between planting density and the height of the tree from which the samples were taken for all measured fiber properties studied. The chemical composition of the clone of rubber wood was determined as per TAPPI standards. Each of the chemical constituents of the rubber wood displayed statistically significant (at the 95% confidence level) interactions with tree section (low, middle, or high) and planting density. Fiber morphology and chemical composition results showed that juvenile rubber trees could supply fiber to produce particleboard and medium density fiberboard. Compared to mature rubber trees (those more than 25 years old), the studied RRIM 2000 clone rubberwood trees were found to be as compatible for use in the wood industry.

In this study, blended paper was prepared by blending synthetic polyethylene (PE) via a disintegration technique. The produced paper was targeted to resist water or moisture. Unbleached kenaf whole stem pulp was used as the main source of fibre in making the paper. The pulp was blended with two types of PE: low-branched (LB) and high-branched (HB) polymers. To study the effect of PE addition to the paper, the water absorbency and mechanical properties were characterized. The pulp to PE mixtures were prepared at ratios of 9:1, 8:2, 7:3, 6:4, and 5:5. Scanning electron microscopy (SEM) showed that the PE was melted between the fibre linkages. The Cobb test determined that the blended paper absorbed less than 20 g/m2 of water within 60 s. The best water contact angle successfully achieved was at 84°, which is almost hydrophobic. The mechanical properties, such as tensile strength and tear strength, were in the range of accepted standard requirements. The obtained results indicated that blending via a disintegration technique can be applied in the process of making water-resistant paper. The produced paper is suitable for the manufacturing of water-resistant corrugated packaging materials.

This study investigated the effects of heating on the morphology, pH, and buffering capacity of bast and core kenaf fibre. The bast material yielded longer and thinner fibres (with a higher aspect ratio) compared to the core. Changes in fibre morphology were clearly visible when the temperature of pulping was increased. The morphology of the bast fibre displayed significant variations following treatment at different pulping temperature (150, 160, 170, and 180 °C), time (1, 2, and 3 hours), and with the interaction between both parameters. Core fibre also exhibited significant variation in length, width, and wall thickness in all parameters, but lumen diameter and aspect ratio were not significantly affected by the same processing conditions. The pH value of both fibres was reduced as the temperature increased; core fibre was more acidic compared to bast fibre. Bast fibre exhibited greater acid buffering capacity and core fibre greater alkaline buffering capacity.

This paper reviews several empirical studies which highlight the using of kenaf for pulp production (beating, fractionation, and recycled fiber). Kenaf is a non-wood pulp source that is alreadly used in parts of the world. Review studies showed that being a dicotyledonous plant, kenaf stem consists of bast and core fibers that are significantly different in chemical and morphological properties. Fiber properties directly influence pulping conditions applied in pulp and papermaking production. Kenaf fibers due to different nature and structure exhibit different behavior during pulping and papermaking. Core pulp due to presence of components with a high surface area coming from pith has low freeness and enhance susceptibility to refining action and pulp rapidly attains freeness value that are quite prohibitive for practical purposes. These short comings restrict the use of core pulp, which probably better used as unrefined. On the contrary, bast pulp refines easily and develops its strength. Due to difference in the quality of bast and core fiber, some researchers have proposed to fiber separation and pulping of each fraction separately and using each pulp lonely or blending refined bast pulp and unrefined core based on final product properties. These review results showed that, there is promised to use of kenaf as whole stem (bast and core together) for technical and economical advantages.

In this study, oil palm empty fruit bunch fibres (EFB) reinforced polypropylene (PP) composites were prepared by two different methods i.e. physical treatment of the composites using electron beam irradiation and chemical treatment by adding coupling agent such as maleated PP. The composites pellets were then subjected to injection moulding for preparation of test pieces for physical, mechanical and rheology properties study. Haake Rheometer RS 150 was used to study the changes in viscosities of the composites at different shear rates. The melt flows of the composites were also measured to complement and confirm the rheology behaviour of the composites. Upon irradiation, the viscosity of PP decreased due to chain scission and the sudden drop of viscosity at high shear rate was not significant. The presence of EFB fibre in the PP matrix was obviously interrupted the flow ability of PP that cause viscosity to increase. Upon irradiation of EFB/PP, the viscosity of the composites decreases. This indicate that...