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Kenaf fiber is gaining prominence because of its ability as a natural-based reinforced material in advanced composites. However, kenaf contains a hygroscopic natural waxy substance that covers the fiber layer, providing a low surface tension and preventing strong bonding with the polymer matrix. The goal of this study is to optimize the blending parameters of kenaf fiber-reinforced epoxy composites by alkali treatment concentration, length, and fiber-matrix loading using central composite design. The maximum tensile strength was obtained at 6.03 wt% of NaOH concentration, fiber loading of 26.02 wt%, and fiber length at 7.39 mm, which showed a strong correlation between experimental and predicted values. The analysis of variance function model indicated that fiber length, sodium hydroxide concentration, and fiber loading all play important roles in mechanical properties of composites. Based on the fracture surface observations, kenaf fiber composite strength was closely related to bonding at fiber-matrix interfaces. The most common failure modes in the samples were voids, matrix fracture, fiber breakage, weak bonding, and fiber pull-out.

The current work discusses ground coffee waste (GCW) reinforced high-density polyethylene (HDPE) composite. GCW underwent two types of treatment (oil extraction, and oil extraction followed by mercerization). The composites were prepared using stacking HDPE film and GCW, followed by hot compression molding with different GCW particle loadings (5%, 10%, 15% and 20%). Particle loadings of 5% and 10% of the treated GCW composites exhibited the optimum level for this particular type of composite, whereby their mechanical and thermal properties were improved compared to untreated GCW composite (UGC). SEM fracture analysis showed better adhesion between HDPE and treated GCW. The FTIR conducted proved the removal of unwanted impurities and reduction in water absorption after the treatment. Specific tensile modulus improved for OGC at 5 vol% particle loading. The highest impact energy absorbed was obtained by OGC with a 16% increment. This lightweight and environmentally friendly composite has potential in high-end packaging, internal automotive parts, lightweight furniture, and other composite engineering applications.

The mechanical properties of oxo-biodegradable high-density polyethylene (oxo-HDPE) composites reinforced betel nut husk (BNH) fibre were studied in this research. A neat oxo-HDPE laminate and four betel nut fibre reinforced oxo-HDPE composites were fabricated using hot press compression moulding method. The composites contain 7%, 12%, 17%, and 22% fibres volume fraction respectively. The cross section of the composite was observed under scanning electron microscopy (SEM) and all five laminates are put through tensile test and hardness test. The result of the study shows that adding betel nut husk (BNH) fibres as reinforcement increases its tensile strength, specific tensile strength, and hardness of the composites. The good lamination observed under scanning electron microscopy (SEM) enable good transfer and distribution of stresses from the matrix to the fibres.

Most rural locations in East Malaysia are not electricity grid connected. These places rely heavily on high-cost diesel fuels for generating electric power, which can be environmentally unfriendly. Most of all, this situation hampered the potential growth in terms of economic productivity and developments in these rural locations. However, with the vast network of streams and rivers available in Sarawak, there are high prospective of constructing micro-hydro power plant as electricity generating alternative. Efforts and studies on micro hydro power plants have been put in place. However, there exists a gap in the field of study of optimized design and construction of micro-hydropower system. This project proposed a Value Engineering (VE) study in the civil and structure sections of micro-hydro plant in Kampung Assum, Sarawak in order to achieve high functional value for the facility. Based on the literature review several VE methodologies are adopted and modified in order to achieve the objectives of this study. VE Job Plan was utilized as the backbone of this research study framework. VE calculation modelling is produced and conventional micro-hydro power plant is designed using the modelling as control baseline design. Ideas to further optimise and improve the value of the micro-hydro system are generated and evaluated, which are then compared with the control baseline design. Several cycles using the proposed VE methodology are repeated to determine the most prominent idea, which can uplift the functional value of the micro-hydro system significantly. Determination of value for micro-hydropower system is dependent on the cost incurred and the efficiency of the civil and structural components as a whole. The chosen idea is then used to the next development phase which notable changes in parameters of micro-hydro civil structures are further determined to improve the value. In this study, evaluating the micro-hydro civil components as a whole with adjustments made to modify the overall output data are discovered to be the prominent idea. From this study, the optimisation proposed could improved the functional value of the micro-hydro power plant in Kampung Assum by a significant 17%.

Natural fibre reinforced polymer composite (NFRPC) has successfully replaced other synthetic fibre for applications in automobile, sport equipment, furniture, electrical appliances, etc. Artocarpus heterophyllus or jackfruit are mass produced in most South East Asia, but most of the parts other than the fruit would go to waste. In this study, Artocarpus heterophyllus fibre reinforced high density polyethylene (HDPE) composite was fabricated and tested for its mechanical properties, such as tensile and hardness properties. Artocarpus heterophyllus fibres were made into sheets using traditional paper making process, before being laminated with HDPE films using hot press method. Different volume fraction of fibre laminates were produced: 10%, 13%, 17% and 21%. The study shows that composite with 10%, 13% and 17% fibre volume fraction exhibits better tensile strength and hardness value than neat HDPE, while composites with 13%, 17% and 21% fibre volume fraction exhibit higher tensile modulus than neat HDPE. The optimum fibre content for the Artocarpus heterophyllus composite is 17%.

Effect of alkali treatment on ground coffee waste/oxobiodegradable HDPE (GCW/oxo-HDPE) composites was evaluated using 5%, 10%, 15%, and 20% volume fraction of GCW. The composites were characterized using structural (Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM)), thermal (thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC)), mechanical (tensile and impact test) properties, and water absorption. FTIR spectrum indicated the eradication of lipids, hemicellulose, lignin, and impurities after the treatments lead to an improvement of the filler/matrix interface adhesion. This is confirmed by SEM results. Degree of crystallinity index was increased by 5% after the treatment. Thermal stability for both untreated and treated GCW composites was alike. Optimum tensile result was achieved when using 10% volume fraction with enhancement of 25% for tensile strength and 24% for tensile modulus compared to untreated composite. Specific tensile strength and modulus had improved as the composite has lower density. The highest impact properties were achieved when using 15% volume fraction that lead to an improvement of 6%. Treated GCW composites show better water resistance with 57% improvement compared to the untreated ones. This lightweight and ecofriendly biocomposite has the potential in packaging, internal automotive parts, lightweight furniture, and other composite engineering applications.

Pandanus atrocarpus, or locally known as mengkuang plant is likely to be potential natural fibre reinforcement in composite. Both the Pandanus leaves, and fibres extracted from the Pandanus leaves were used in composite fabrication. Fibres were extracted from Pandanus leaves with water retting process. Pandanus composites were laminated using compression moulding method. The tensile properties of composite laminates based on lamination of Pandanus leaf- and extracted Pandanus fibre-reinforced polyethylene were investigated. Tensile tests have shown that composite laminates based on extracted Pandanus fibre reinforced polyethylene were more superior than using the Pandanus leaf itself without extracting its fibre. Tests exhibited that increasing the volume fraction of Pandanus fibre resulted in strength increase. This suggests that Pandanus fibre- based composites could offer a range of mechanical properties for use in the engineering industry.

Annual polymer waste generated in Malaysia has increased significantly to more than 1 million tonnes. The prolonged degradation periods required by diverse industrial polymer waste streams are a matter of significant concern, with some taking up to 1000 years to fully degrade. Pursuing a similar environmental concern, the use of bakau piles as supports for lightweight structures in Sarawak, including drainage systems, roads, sewerage, and other water-related structures, has become a matter of concern due to the deforestation of mangrove forests. Both bakau deforestation and polymer waste issues are significant environmental and global concerns. The idea of mitigating mangrove degradation and the non-biodegradable nature of polymer waste has led to the conceptualization of an alternative solution whereby recyclable thermoplastic polymer piles are utilized to supplant bakau piles in providing support for lightweight structures during civil engineering construction projects. Therefore, the study of polymer piles is conducted to examine their mechanical properties in the form of virgin (V) and recycled (R) thermoplastic polymers. In this study, high-density polyethylene (HDPE), polypropylene (PP), and polyvinyl chloride (PVC) are considered, and the possibility of being utilized in pile application has been discussed. Based on the results, all virgin types of thermoplastic polymers (HDPE, PP, and PVC), 50%V:50%R for PP, PP(R), and PVC(R), respectively, exceed the bakau ultimate tensile strength. Thermoplastic polymer piles showed great potential to be the substitution for bakau piles to serve in the construction industry, with the recorded experimental tensile and compressive strength tests. [ABSTRACT FROM AUTHOR]

Kenaf fiber is gaining prominence because of its ability as a natural-based reinforced material in advanced composites. However, kenaf contains a hygroscopic natural waxy substance that covers the fiber layer, providing a low surface tension and preventing strong bonding with the polymer matrix. The goal of this study is to optimize the blending parameters of kenaf fiber-reinforced epoxy composites by alkali treatment concentration, length, and fiber-matrix loading using central composite design. The maximum tensile strength was obtained at 6.03 wt% of NaOH concentration, fiber loading of 26.02 wt%, and fiber length at 7.39 mm, which showed a strong correlation between experimental and predicted values. The analysis of variance function model indicated that fiber length, sodium hydroxide concentration, and fiber loading all play important roles in mechanical properties of composites. Based on the fracture surface observations, kenaf fiber composite strength was closely related to bonding at fiber-matrix interfaces. The most common failure modes in the samples were voids, matrix fracture, fiber breakage, weak bonding, and fiber pull-out. [ABSTRACT FROM AUTHOR]

Considering the cost in utilization of organic natural filler as an alternative to manmade fiber and mineral inorganic filler-reinforced polymer composite is of great interest. The main reasons for using natural fillers are to reduce the dependence on petroleum-based, nonrenewable resources and are also a smarter use of environment and financial resources. Only limited research works have been done on the mechanical properties, such as tensile, flexural, and impact on particulate organic natural filler-reinforced polymer composite. The effect of particle size, particle loading, and chemical treatment on mechanical properties of organic natural filler-reinforced polymer composites is reviewed and discussed. The results show that a smaller particle size with an aspect ratio higher than its critical value provided better mechanical properties. With the assumption of good adhesion between the particle filler and matrix, mechanical properties increased with volume fraction until it reached its optimum condition or failure. Effective chemical treatments would improve the homogeneity and adhesion of the filler/matrix, thus enhancing the mechanical properties of the composites. [ABSTRACT FROM AUTHOR]