The hybridisation of natural fibre with glass fibre provides a method to improve the mechanical properties instead of using the natural fibres alone. This research is focused on the hybridisation of glass/kenaf fibre with the addition of liquid epoxidised natural rubber to enhance the desired mechanical properties of the composite by reducing the synthetic fibre usage and encourage the natural fibre consumption. Liquid epoxidised natural rubber was added to the epoxy matrix in order to improve its mechanical properties whilst E-glass fibre and kenaf bast fibre were used as the reinforcement in the composite. Liquid epoxidised natural rubber (3%) was added as a toughening agent. Two types of kenaf fibre were prepared -untreated and treated with 6% NaOH -whilst the glass fibre was treated using a silane coupling agent. The flexural test, Izod impact test, environmental stress cracking resistance analysis and scanning electron microscopy analysis were performed to determine the effect of fibre treatment and liquid epoxidised natural rubber addition on the mechanical properties of the hybrid fibre-reinforced composite. It was found that the treatment and the addition of liquid epoxidised natural rubber contribute to the increment of the impact strength by 40% whilst the flexural properties recorded a 13% and 15% increment for both flexural strength and flexural modulus, respectively. The environmental stress cracking resistance analysis showed that the composites are more affected in acid medium followed by base medium and then with the control medium (air). The addition of liquid epoxidised natural rubber seems to improve the stability of the samples in the medium initially but tends to decrease rapidly over time due to debonding of the rubber particles.

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Glass fiber epoxy composites are widely used in industries. Liquid epoxidized natural rubber was added to epoxy as the matrix for a fiber-reinforced composite in order to improve its mechanical properties whilst E-glass fiber was used as the composite reinforcement. Flexural test, Izod impact test, tensile test, thermogravimetric analysis, and scanning electron microscopy were performed to investigate the effect of liquid epoxidized natural rubber addition and glass fiber loadings on the mechanical properties of the composite. It was observed that the flexural strength and flexural modulus of the samples increased with increasing glass fiber percentage with 9% as the maximum weight percentage recorded. The tensile strength and Young’s modulus increased with increasing glass fiber content until it reached the maximum value at 9 wt% of glass fiber. The same trend was observed with the impact value of the samples. All the tests were conducted for the composite with and without liquid epoxidized natural rubber addition. The presence of liquid epoxidized natural rubber improved the mechanical properties of the composites due to the plasticizing effect of the rubber particles in the matrix. Thermogravimetric analysis revealed the thermal stability of the composites whilst the scanning electron microscopy shows a heterogeneous dispersed phase of morphology. There was poor adhesion between the matrix polymer and glass fibers due to the use of untreated glass fibers.

Concrete currently has become a conventional material in construction of nuclear reactor due to its properties such as safety, strength and economical in cost. Boron carbide (B4C) was used as additives in concrete are characterized as a good neutron absorber for nuclear reactor applications. The effect of B4C addition on physical and strength properties of concrete samples were investigated. The samples were prepared with three different weight percent (wt%) of B4C powder. The concrete slump tests of fresh concrete have been done to investigate the workability of mixtures. Free B4C mixture shows the highest workability compare to 5 and 20 wt% B4C concrete mixture. The density of 0 wt% of B4C is the lowest compared to 5 and 20 wt%. However, after 28 days curing time, the compressive strength test of 20 wt% B4C shows the highest value compare to 5 and 0 wt% B4C concrete respectively. It is obvious that up to 20 wt% B4C can be added to concrete mixture and cause significant strength increases.