Impact Studies in Elastomer, Fly Ash, and Hybrid-filled Epoxy Composites: Part I - Room Temperature Curing

This study involves a system where epoxy as matrix and two reinforcements, namely an elastomer and a less dense oxide known as fly ash, differing in their response to mechanical loading to yield hybrid composite, are used. As rubber particles are known for their resistance to dynamic loading situations, poly(acrylonitrile-co-butadiene), carboxyl terminated, CTBN as the elastomer constitutes the first of the filler. The incorporation of rigid fly ash, as a second filler, has been made to see the change in the behavior in the response to the impact test. Their roles as individual fillers as well as hybrid fillers are studied at various compositions. The directly observed experimental values such as total energy and the derived data like ductility index (DI) are catalogued. While the fly ash-bearing composites show maximum absorption of energy at 3% by weight, the rubber-bearing ones display the same trend at 1%. The values recorded for the hybrid type having 1% were high. The DI showed highest values for the maximum filler bearing compositions in all cases. The scanning electron micrographs of the impact-failed samples helped in understanding the trends seen in the impact data.