Fracture and Damping of Ionomer Interleaved Epoxy Composites

Abstract

A study was conducted on the effect of interleaving on laminated composites. An ethylene-based ionomer of various compositions and a silane-modified ethylene-vinyl-acetate were selected as the interleaving materials. The glass transition temperatures (Tg) of the ethylene-based polymers ranged from-24 to 50'C. The fracture toughness (GIc), impact performance, and damping properties of the composites were evaluated. G₁c of interleaved composites was about 3-5 times higher than that of non-interleaved. However, G₁c was sensitive to the composition of the interleaf. The silane-modified ethylenevinyl-acetate had the highest fracture toughness. The impact properties of the interleaved materials were superior to those of non-interleaved, as evident from CAI testing where delamination occurred at an early stage in non-interleaved samples. The damping ratio of interleaved materials was found to be more than 100 times higher than in the original material.

Keywords

composites interleave epoxy damping fracture toughness isotropic compression impact ionomer double cantilever beam (DCB)

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