Thanawan Chaowasakoo and Narongrit Sombatsompop

pp. 217 - 230

Abstract

In this research, the effect of curing techniques and silane treatment on mechanical and morphological properties of fly ash (20 and 80 phr) filled epoxy composites were studied. The addition of N-2(amino-ethyl)-
3 aminopropyltrimethoxysilane (KBM603) coupling agent was varied 0.0, 0.5, 1.0 and 1.5 %wt of the fly ash, for surface treatment of fly ash particles. The optimum curing conditions of conventional thermal and microwave curing system were determined using a differential scanning calorimetry (DSC). The conventional hermal curing was performed at 70°C for 80 min while microwave curing was carried out at 240 watt for 18 minutes in order to achieve the optimum curing conditions of the composites. The silane concentration of 0.5 wt% was recommended for the optimum mechanical properties of the fly ash, epoxy composites. Beyond these recommended contents, the mechanical properties greatly reduced, except for the flexural moduli. By comparing microwave cured composites with conventional thermal cured composites, it was found that microwave cured composites consumed shorter cure time and had higher ultimate strengths and elongation at break than those by the conventional thermal cure. The composites with higher tensile and flexural moduli could be obtained by the conventional thermal cure. The comparative results of composites cured using different microwave powers showed that the ultimate strengths and elongation at break decreased with
increasing microwave power while the effect was opposite for the tensile and flexural moduli.