Effect of Moisture Content on the Mechanical Property of Natural Fiber Reinforced Composite from Recycled Jute Cloth

In this study, the jute cloth from recycled coffee bags was used to fabricate ecologically friendly composites. Jute clothes with three kinds of different moisture contents were used to fabricate the natural fiber reinforced composites by hand lay up method. As the primal investigation, the effect of moisture contents of the jute cloth on the mechanical properties of the composites was discussed based on the results of 3 point bending and Izod impact tests. In particularly, acoustic emission (AE) technique was applied under a 3 point bending load to detection of the micro-failure processes in jute reinforced composite. The number of AE signals and the AE energy had been monitored by the transducer with the resonant frequency of 140 kHz. Pre- and post-failure examinations were carried out using an optical microscope and scanning electron microscope (SEM). Results showed that the strength of the jute yarn decreased with the decrease of the moisture content which is considered to a decreased of the mechanical properties of composites consequently. However, AE characteristics and observation results on the fracture surfaces indicated the composite fabricated from the low moisture content jute cloth had a relative high initial fracture stress and the resistant to the micro fractures.