Thin films of poly (ethylene oxide) (PEO), poly (methyl methacrylate) (PMMA) and selected blends of PEO/PMMA with and without the addition of LiClO4 were prepared using solution casting technique. The presence of a single Tg which corresponds closely to that of the Gordon Taylor equation confirms the miscibility of both the salt-free and salt-doped blends. The Tgs and the ion conductivity (σ) at room temperature of PEO, PMMA and the PEO/PMMA blends generally increase with ascending salt concentration (Y). Variations in the σ value as a function of Y for all the three systems correlate closely with their respective Tg results. PMMA-salt complex records the lowest σ value at all salt concentrations. PEO/PMMA/LiClO4 blend with 75 wt% PEO exhibits the highest σ value of 5 x 10-7 S cm-1 at Y = 0.10. The σ value of the blend-salt system is observed to be slightly lower than that of the PEO-salt system. This is due to reduced segmental motion cause by increased Tg of the blend and a decrease in free ions in the amorphous phase of PEO as a small amount of the salt is solvated by PMMA in the blend. Therefore, the percolation path lies in the amorphous PEO rich phase of the blend.

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The aim of this study is to determine the effect of alkali treatment on water absorption and tensile properties of non-woven kenaf polyester composite. Kenaf fiber mat was treated with 2, 4 and 6% of different sodium hydroxide (NaOH) concentration. The composite was fabricated using compression molding technique. It was found that treatment reduced the overall water uptake of composites. The 6% treated fibre composite was greater in moisture resistance as compared to untreated. The tensile strength of the composites was substantially improved after alkali treatment, and it was similar with the tensile modulus.

Non steady state diffusion flow is unstable movement of moisture in a material which changes with respect to time. Diffusion coefficient describes the rate at which water moves from the interior to the surface of the materials. Absorption and desorption are the variables that are used to determine the diffusion coefficient. Understanding of the water absorption and desorption is important since it affects the mechanical properties of materials such as strength and durability properties. Water absorption and desorption of the materials or products intended for drying are important for the design and operation of dryers such as kiln drying and other processing system. Nowadays, the processing of solid wood into finish product is decreasing due to increase in the cost of solid wood and insufficient supply of quality logs. Agricultural waste such as pineapple leaves is one of the potential raw materials that can be used in particleboards manufacturing. Pineapple leaves particleboards were produced and the diffusion of coefficient of water absorption, percentage thickness swelling and percentage thickness shrinking were determined. Diffusion coefficient was determined based on the absorption and desorption rate. The particleboards manufacturing followed BS EN 326 and testing of samples was in accordance with BS EN 317. The difference in thickness of particleboard has great influence on physical properties. In this study the particleboard made of 1 cm has the lowest water absorption compared with 2 cm particle board and has highest thickness shrinking.

Increase of awareness among people has increased the demand for green products. Other synthetic materials such as plastic and fibreglass has been reduced because of the environmental concern. Reinforcement with other green materials such as lignocellulosic materials has been done to reduce the dependency on synthetic material. Kenaf (Hibiscus cannabinus L.) fibres have the biggest potential to be used as a composite product and also as reinforcement in the composite products. Lignocellulosic materials including kenaf face some of problems when used as a reinforcement material with synthetic materials especially plastic based materials such as polypropylene and polyester. This problem is related to the properties of the fibres and the synthetic materials thus would reduce the mechanical properties of the product manufactured. Modification of the surface by solution treatment has been the popular method for improving the mechanical properties. In this study modification using Sodium Hydroxide or NaOH at three different concentration has been conducted to investigate the influence on the mechanical properties in terms of elasticity and strength properties of the composite material manufactured. The polyester composites were manufactured and tests according to ASTM D790-02 for bending test. Six replications of each type were tested and the values were evaluated using statistical analysis software. All the samples for both MOR and MOE showed significant differences for each type. Based on the result the highest value of the polyester composite was the kenaf that treated with 3% of NaOH solution for both MOR and MOE value.