Effect of alumina tri-hydrate filler on the mechanical and optical properties of flame-retardant ultraviolet cured vinyl ester composites

Abstract

This research study is focused on the effect of alumina tri-hydrate (ATH) filler on the mechanical and optical properties of flame-retardant ultraviolet cured vinyl ester composites. In particular, vinyl ester formulations for out of die ultraviolet (UV) cured pultrusion has been analysed. Different matrix formulations varying the percentage of ATH (0 phr, 10 phr, 20 phr, 30 phr and 40 phr) have been compared. The through-thickness light transmission is critical in the studied process, in order to avoid the expansion at the exit of the die. Thus, the optical properties of the composite have been measured by a spectroradiometer during the curing process of the composites. The results show that the light transmission during the curing process is moderately affected (20%) by the presence of ATH up to 30 phr. In the case of 40 phr of ATH, the decrease of light transmission is more accused (35%). However, as the temperature of the composite increases as the ATH content increases, the curing degree is not negatively affected in these conditions. Regarding the mechanical properties, no significant differences of the interlaminar properties have been reported in the composites filled with ATH compared to the basic formulation (0 phr ATH).