Composite from aggregates and vetiver grass fiber using natural rubber latex as a binder

Abstract

The main objective of this research is to study the mechanical and physical properties of the composites made from aggregates (such as clay, sand, laterite and crushed stone) and vetiver grass fiber. The compositions of aggregates and vetiver grass fiber were varied at 100:0, 30:70, 50:50, 70:30 and 0:100, respectively. Latex compound with 20% dry rubber content (DRC) was used as a binder. The properties of composites including the bending test before and after aging, density and water absorption were investigated. The results indicated that composites with the ratio of aggregates and vetiver grass at 30:70 of each formula gave highest flexural strength before aging. Due to the highest flexural strength before aging (1,182 kPa) and water absorption (98.65%), composite made from laterite and vetiver grass fiber were chosen to study degradation test and the toxicity of composite on soil quality. It was found that composites made from laterite and vetiver grass fiber degraded after buried in soil for 90 days. The content of cadmium and chromium in soil were lower than those of the standard of soil quality for household and agriculture. Moreover, the degradation of composites caused an increase in the content of soil organic matter but did not alter in pH value of soil.