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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.

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.

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, 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.