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In this study, glass fiber-reinforced epoxy-nanoclay composite plates, with I.30E clay contents ranging between 0 and 5 wt.%, were manufactured by hand layup with hot pressing. Flexural strength of unexposed fiber-reinforced epoxy-nanoclay reached an optimum improvement of 11% for 1.5 wt.%. Scanning electron microscope analysis showed that at this clay loading, better interfacial adhesion of clay with glass fibers was achieved. At higher clay loadings, clay agglomeration and presence micro-voids led to less strength improvement. The maximum water uptake was found to decrease with increasing clay loading and moisture diffusion at 80℃ was about 80% higher than that at room temperature. Post exposure flexural tests revealed a behavior similar to that of unexposed samples with nanoclay loading of 1.5 wt.% leading to optimal flexural properties. Exposure to moisture resulted in degradation of fiber-reinforced epoxy-nanoclay flexural properties with about 36% reduction in strength for 80℃ and 8% for room temperature.

The wide use of petroleum-based oils raises concerns with regard to pollution, and the rising of awareness of greenhouse gases has created a demand for the use of environmentally friendly and biodegradable lubricants for industrial applications. Vegetable oils are one of the bio-oils that have been promoted as a replacement for petroleum products, in part due to their environmentally friendly characteristics; they are nontoxic, biodegradable, and easy to dispose of. Many researchers have performed studies on sunflower oil, corn oil, and soy oil, but few have studied palm oil as a lubricant. Palm oil produced in a high-throughput manner could fulfill the demand for biobased lubricants. In this study, the influence of temperature on friction and wear performance for refined, bleached, and deodorized (RBD) palm stearin and additive-free paraffinic mineral oil is presented. The experiments were conducted using a four-ball tribotester. Test temperatures of 55, 65, 75, and 85 • C were used. The sliding speeds were set to 1,200 rpm. Experiments were run for 1 h under a 392.4 N load. The results of RBD palm stearin were compared with those of paraffinic mineral oil. The experimental results showed that the RBD palm stearin had better performance compared to paraffinic mineral oil in terms of reducing frictional constraints.

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The mechanical and physical properties of epoxy-clay nanocomposites are known to be significantly affected by the dispersion and distribution of the clay particles in the epoxy matrix. The degree of dispersion of the clay particles in the epoxy matrix depends mainly on the processing parameters used to synthesize the nanocomposite.In this paper, the optimized high shear mixing parameters determined in an earlier work were used to disperse five different loadings of Nanomer I.30E nanoclay (1, 1.5, 2, 3 and 5 wt%) into DGEBA epoxy matrix. A systematic approach was adopted to optimize the degassing process of the mixture. X-Ray Diffraction (XRD) analyses showed that the optimum nanoclay dispersion was achieved for a degassing temperature of 120 °C. The flexural strength of the developed nanoclay/epoxy composite is found to increase by 15% for 1.5 wt% and due to the high stiffness of the clay, as compared with epoxy resin, the flexural modulus improved continuously with clay loading. The observed reduction in strength and fracture strain at high clay loadings is mainly attributable to the presence of clay agglomerations and voids formation. The diffusion of water molecules and maximum moisture uptake of epoxy are reduced considerably by the presence of nanoclay.

Addition of organoclay to polymer matrix has recently attracted industry attention due to improved physical properties with an overwhelming potential in crude oil and water pipe applications. In this work, electrical grade-corrosion resistant (E-CR) glass fiber mats were used to prepare glass fiber reinforced epoxy (GFRE) nanoclay composites using hand layup method. Three different hybrid GFRE composites were made using 0, 1.5 and 3 wt% loading of I.30E nanoclay. High shear mixing was used to prepare the epoxy/clay nanocomposite. XRD results revealed a disordered intercalated morphology. The effect of nanoclay on mechanical properties were investigated by carrying out flexural and fracture toughness tests. The test results showed that addition of nanoclay up to 1.5 wt% improved both flexural strength and fracture toughness. However, these properties deteriorated when the clay content increased to 3 wt%.

Daya geseran untuk minyak sawit olein yang ditapis, diluntur dan dinyahbau (RBD olein) telah dinilai dengan menggunakan alat tribotester pin-atas-cakera. RBD olein telah dipilih kerana sifat-sifat unggul tribologi dan pengeluarannya yang besar di Malaysia. Dalam kajian ini, 5ml minyak RBD olein telah digunakan pada cakera beralur. Pin yang mempunyai hujung rata telah digunakan sebagai bahan ujikaji. Cakera dan pin diperbuat daripada titanium alloy. Beban normal yang dikenakan pada pin ialah 4.96N dan 19.68N. Ujikaji telah dijalankan selama satu jam. Kadar haus pin dan pekali geseran telah dikira. Ujikaji yang sama telah dijalankan dengan menggunakan minyak hidraulik komersial dan minyak mineral jenis parafinik yang tidak mengandungi bahan tambah. Pekali geseran yang dihasilkan oleh pelinciran minyak sawit RBD olein adalah terendah berbanding minyak mineral parafinik pada kedua-dua jenis beban(4.96N dan 19.68N). Bagaimanapun, minyak sawit RBD olein menunjukkan kadar haus yang tinggi berbanding minyak mineral parafinik pada beban normal 19.68N. Kata kunci: Pin-atas-cakera; minyak sawit; palm olein; haus; pekali geseran A friction resistance of refined, bleached and deodorized (RBD) palm olein was evaluated using a modified pin-on-disk tribotester. RBD palm olein was selected due to its superior tribological properties and large production in Malaysia. In this research, 5ml of RBD palm olein was applied on the rotating grooved-disk. The flat-ended pin was used as a specimen. The material was titanium for both pin and disk. The normal loads applied are 4.96N and 19.68N. The experiments were run for one hour. The wear rate of the pin and friction coefficient was calculated. Same experiments were conducted using commercial hydraulic oil and additive-free paraffinic mineral oil. The results were compared with RBD palm olein. The friction coefficient with the lubrication of RBD palm olein was the lowest for 4.96N and 19.68N under normal load conditions. Wear rate obtained by RBD palm olein at normal load 4.96N was the lowest; however, RBD palm olein showed a high wear rate when high normal load (19.68N) was applied. Keywords: Pin-on-disk; palm oil; palm olein; wear; friction coefficient

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