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Despite having remarkable features such as low density, ease of fabrication and recyclability, linear low-density polyethylene (LLDPE) has several drawbacks like poor stiffness and low creep resistance which fortunately can be improved by incorporating with other suitable nanofillers. In this study, graphene nanoplatelets (GNPs) that are well-known for its high surface area and superior stability were selected to reinforce the polymer network of LLDPE via melt blending. During mixing processing, the rotor speed, mixing temperature and mixing time parameters are manipulated with the aids of 5-level-3-factor central composite rotatable design (CCRD) in order to determine the optimization of processing parameters in preparing LLDPE/GNPs nanocomposites. The experimental data is fitted with the statistically significant quadratic model with R2 value of 0.8601. The results showed that the tensile strength of LLDPE/GNPs nanocomposites could be extended to 24.80 MPa.  The optimum processing parameters for preparation LLDPE/GNPs nanocomposites were found to be at 101 rpm rotor speed, 139.8oC of mixing temperature and 13.2 min of mixing time, resulting in LLDPE/GNPs nanocomposites with tensile strength of 24.11 MPa. Conclusively, our study has provided a novel statistical design of experiment to obtain the optimum processing parameters in preparing LLDPE/GNPs nanocomposites.

In this study, kenaf (Hibiscus cannabinus) core particleboards as insulation boards were manufactured. The boards were fabricated with three different densities i.e. 350 kg/m3, 450 kg/m3 and 550 kg/m3 at urea formaldehyde resin (UF) loadings of 8%, 10% and 12% (w/w) based on the dry weight of the kenaf core particles. The fabricated boards were evaluated for its noise acoustical coefficients (NAC) by following the ASTM E1050-98 standard requirements. The study revealed that boards with higher kenaf fiber loading and UF loading gave less NAC.

Single layer kenaf (Hibiscus cannabinus) core particleboards bonded with urea formaldehyde (UF), phenol formaldehyde (PF) and polymeric 4,4-methyl phenylmethane di-isocyanate (PMDI) resins were manufactured. The boards were fabricated with three different densities i.e 350 kg/m3, 450 kg/m3 and 550 kg/m3. Each type of the resin used was sprayed at three different resin loadings on the kenaf core particles. The boards produced was evaluated for its modulus of rupture (MOR), modulus of elasticity (MOE), internal bond (IB), screw withdrawal (SWD), water absorption (WA) and thickness swelling (TS) in accordance with the British Standards. The study revealed that boards with higher resin contents gave higher MOR, MOE, internal bond and screw withdrawal and also improved the water absorption and thickness swelling. Similar trend was also observed from boards with higher densities. It is concluded that the boards with the density of 550 kg/m3 were able to fulfill the British Standard specifications.

One layer kenaf core particleboard was treated with one of the advanced fire retardants, Dricon® . The percentage of 8 % (w/w) and 12 % (w/w) of Dricon® were incorporated into three different board densities (350 kg/m3, 450 kg/m3 and 550 kg/m3) which were fabricated with three resin loadings (w/w) of urea formaldehyde (8%, 10% and 12%). Each of treated and untreated particleboard has been tested with blow torch and fire propagation tests. The fire propagation test was evaluated by using performance index (I), which indicates the level of heat release of the tested boards. Blow torch test resulted the decreasing of sample’s weight loss of the Dricon®’s sample than the control samples. Fire propagation test indicated lower value of performances index or lower heat release of the treated samples compared with the untreated ones.

The study on the kenaf core fiber – polypropylene (PP) composites with treated and non-treated maleated polypropylene (MAPP) was done. Epolene-43 which is commercially MAPP was used to determine MAPP’s effectiveness as a coupling agent for kenaf fiber-composites. The hot pressing system for producing kenaf core-PP composite has been used. The tensile, impact and thickness swelling results of the epolene 43 treated composite samples were better than those of the untreated composites. Scanning electron microscopy micrograph proved that the interfacial region of treated composite board shows good interaction among kenaf’s wood fiber and PP components.

The curing time and the properties of urea formaldehyde (UF) resin mixed with fire retardants, BP (mixture of boric acid, guanylurea phosphate and phosphoric acid), monoammonium phosphate (MAP) and diammonium phosphate (DAP) were studied. There were two amounts used, 8% w/w and 10% w/w. The curing time of the mixed resin was determined by using thermo oil at the temperature of 170ºC. Water absorption test and physical observations were done to evaluate the properties of the fire retardant-mixed resin. The non-fire retardant UF resin samples were used as controls. The solubility of MAP and DAP in the water at different weights also has been studied. The solubility test was done with and without the involvement of heat. The study showed that UF resin mixed with MAP and BP cured faster than DAP-mixed UF and control samples. The time taken for UF resin to mix with 10 % w/w and 8 % w/w MAP were 20 s and 28 s respectively. The time taken for UF resin mixed with 10 % and 8 % w/w DAP was slightly than the controls, which are 160 s and 150 s respectively. The time taken for UF resin mixed with 10 % w/w and 8 % w/w BP was 101 s and 92 s respectively.The curing time for control samples was 140 s respectively. MAP and DAP were shown to be highly soluble, as they took less than 1 minute to be dissolved in the water without heat, but BP took 30 minutes to be dissolved in the water without heat and less than 1 minute with heat. Water absorption test showed that the higher the amount of MAP, DAP and BP mixed into the resin, the higher would be the rate of water absorbed.

The degradation of fibre-based products cannot be stopped but can only be delayed by adding additives. The strength properties of both Medium Density Fibreboard (MDF) and Particleboard will decrease parallel to the time and duration of usage due to the degradation in glue bonding. The objective of this study was to estimate the degradation of strength properties of MDF and Particleboard after being condition in an air-conditioned room and at ambient.The duration of the conditioning was three months. These studies compared different board variables (exposure condition, board thickness, resin type, board type) that affect the degradation of board strength. This study alsoexamined the effect of cold-water soaking (12,24 and 72 hours) on the strength of boards. The static bending and internal bond test were used to assess the strength properties of both panel types. The MDF and Particleboard samples were obtained from commercial plants and the test sepcimens were prepared in accordance to JIS A 5908-1994. The Modulus of Elasticity (MOE), Modulus of Rupture (MOR) and Internal Bond (IB) were determined after 0 and 3 months whereas for soaked specimens after 12, 24 and 72 hours. The results showed that all the variables studied exposure condition, board thickness, resin types and board types had great significant influence on the degradation of the board's strength properties. Among the variables studied, board types and conditioning method seems to have more dominant effect compare to resin type. Conditioning the MDF and particleboard in air-conditioned room is much better than at ambient in term of MOE, MOR and IB. The thickness of the board greatly affects the strength retention of the board when exposed either in an air-conditioned, at ambient or soaked in cold water. This shows that, the higher board thickness, the greater the degradation occured.