Over the past century, there has been a dramatic increase in natural fibre composites in which natural fibre has served as reinforcement in polymer. However, the existence of moisture and defects in natural fibres has impacted the mechanical and physical properties of natural fibre polymer composites. The main objective of this study is to fabricate the buri palm fibre reinforced epoxy composite and evaluate the effects of fibre treatment on water absorption and tensile properties. The buri palm fibre were treated by using 5 wt.% NaOH for 24 h and the laminated composite of untreated and treated four-layer and five layer fibres were fabricated via hand lay-up process. The tensile specimens are prepared according to the ASTM D638 standard and the water absorption experiment was conducted by immersing the specimen in distilled water at room temperature until it reached the saturated moisture absorption. The results revealed that the percentage of moisture uptake was reduced to 69% and 95% in treated four-layer and five-layer sequences. It is observed that the thickness swelling of the composite increased with the increase of sequence layering, while the thickness swelling decreased with treated fibre. Alkali treatment affected the properties of buri palm fibre which improved the interfacial bonding between the fibre and epoxy matrix for better tensile properties and reduced water absorption. Finally, morphology examinations were carried out to analyse the fracture behaviour and fibre failure on the tensile test specimen by using microscope analysis.

The transformation of kaolin to metakaolin was studied in various state in Malaysia which is Segamat, Nitar, Lenggor, Ipoh, Bidor, Mersing, Sabah, and Sarawak. In Segamat, the kaolin has a light colour due to the high silicate composition and also contain high mineral such as kaolinite and quartz existed as impurities. Aluminum rich kaolin is bright in color with elevated plasticity and is commonly used in the ceramic, plastic, dye, fabric, pesticide, pharmaceutical and beauty industry. For Nitar and Lenggor, production of metakaolin occurs at 510°C and formation of mullite occur at 900°C. Both clays show good crystallization of pseudohexagonal to hexagonal kaolinite particles. Moreover, the classification of clay and the sizing are the significant characteristic to be determined using the method of the beneficiations. The method of beneficiations is crucially important to increase the quality of clay to meet the requirement for industry application. In Ipoh and Sarawak, the primary deposit is dominated by kaolin and the mixture of granites and diorites produced from weathering. On the other hand, in Bidor, the primary deposit is a mixture of kaolinite, muscovite and smectite also formed by weathering. The increasing amount of illite in secondary kaolin deposits in the Mersing area due to the marine deposition of those deposits where illite formed by the absorption of clay minerals from the seawater by pottasium. Kaolin in Kg Gading, Bongawan Sabah were treated with sodium hexametaphosphate to remove impurities in natural kaolin. The transformation of kaolin to metakaolin was conducted at 800°C for 5 hours.

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Titanium dioxide, TiO2 nanoparticles are being utilized in various application of science and technology including membrane, medical, electrical and chemical field for their respective worth which generally attributed to the self-cleaning and photocatalytic ability, good band gap, an antibacterial as well as physical and chemical stability. As commonly known conventional TiO2 nanoparticles synthesized using chemicals as reducing agents has become accountable for various biological risks due to their general toxicity, thus engendering the serious concern in developing environment friendly processes. Naturally derived products, such as extracts of plants that composed of biomolecules, have been used intensively recently as a reductant agent, that also sometimes can be acting as capping agents after synthesis process. These natural biomolecules mostly consisted of polyphenols have been identified to be actively play a role in this biosynthesis of nanoparticles from any plants extract that able to form different shapes and sizes of nanoparticles with better surface reactive area, characteristic and properties. Therefore, biosynthesis can be considered as a driving force for the greener, safe and environmentally friendly for many applications that have used TiO2 particles either used as additive, purely or in composite form. The present review targets on the ‘greener’ routes of synthesis TiO2 nanoparticles with an emphasis on experimental conditions based on sustainable methodologies and also explores the huge plant diversity to be utilized. The use of ‘greener’ not only reduces the cost of synthesis but also minimizes the need of using hazardous chemicals and stimulates green synthesis. This review also focuses on aspects characteristic and properties that generated from the output of this green process that make it strongly applicable to certain applications as for binding of biomolecules, to the biosynthesized is significantly benefit to biomedical fields. It is expected that these outstanding findings will encourage researchers and attract newcomers to continue and extend the exploration of possibilities offered by nature and the design of innovative and safer methodologies towards the synthesis of nanomaterials, possessing desired features and exhibiting valuable properties that can be exploited in a profusion of fields.