Dynamic-mechanical properties as a function of luffa fibre content and adhesion in a polyester composite

In this work, the characteristics of a vegetable fibre (luffa cylindrica) polyester composite are studied as a function of fibre surface treatment (with NaOH, Ca(OH)2 and silane) and fibre content (30%, 40% and 50%). Composites were prepared through compression moulding and characterized with thermogravimetric and dynamic-mechanical analyses. Higher storage modulus was obtained with Ca(OH)2 treated composites, reaching nearly 70% increase. Higher loss modulus (E”) was noted in for silane treated fibre (at 50%) and a high peak in damping factor was noted for Ca(OH)2 treated fibre (at 50%). Cole-cole plot showed highest homogeneity for the Ca(OH)2 treated composites. Electron microscopy revealed the fracture modes in static tested composites. The general properties obtained indicate that the composites can only be used for low loading applications