Thermally-expandable elastomer molding process for thermoset composite materials

This study examined the elastomer-assisted compression molding process for long-fiber reinforced thermoset composites both experimentally and theoretically. The consolidation pressure generated by a thermally-expandable elastomer was predicted thermodynamically and compared with the experimental value under both fixed-volume and variable-volume conditions during the heating and curing processes. Exhibiting non-linear viscoelastic characteristics, the pressure generated was best described using the modified KWW (Kohlrausch–Williame–Watts) equation. The model equation compared well with the experimental pressure that was measured during the curing process of epoxy matrix composites. The developed modeling methodology demonstrated its capability to predict the consolidation pressure in elastomer-assisted compression molding and autoclave processes.