Effect of Water Absorption on Mechanical Properties of Kenaf and Kenaf Hybrid Polyester

Natural fibre composite materials have been highlighted in recent years as they have the potential to mitigate the pollution and global warming. Kenaf is a high yield and fast growing plant. Kenaf does not require a lot of energy in production. Furthermore, the kenaf plant can absorb carbon dioxide when breathing. The objective of this paper is to relate the effect of different environment to the mechanical properties of kenaf and kenaf hybrid (fiberglass) polyester composites for 60 days period. Kenaf composite (containing 20 wt% of Kenaf fibres) and kenaf hybrid (containing 20 wt% kenaf fibre and 16 wt% fiberglass) were produced in cold press hand lay-up technique and then cured for 24 hours. The specimens were cut as required in EN ISO 527. The specimens were immersed in 3 different water sources, which were rain water, salt water and tap water. Tensile and hardness test were conducted to study the mechanical properties at 10, 20, 30, 40, 50 and 60 days. Both kenaf polyester and kenaf hybrid polyester show reduction on mechanical properties after immersion in the solutions. Kenaf polyester and kenaf hybrid polyester followed fickian behaviour after 40 days water immersion.