Title: Fast Vs Tough; the Effect of Faster Cure Cycles on the Fracture Properties of Toughened Epoxies

Authors: Daniele Incerti, Declan Carolan, and Alexander Fergusson

DOI: 10.33599/nasampe/s.19.1491

Abstract: Epoxy resin systems are widely used in composite materials. Epoxy resins can exhibit high moduli and strengths for polymers, whilst being easy to process into fiber reinforced composites. They can also be considered brittle, when compared to many other polymers. Enhancing the toughness of epoxy-based matrices can lead to significant improvements in the toughness and, therefore, damage resistance of fiber reinforced composites. These improvements in toughness can be achieved through the incorporation and/or formation of nano-scale particles or structures in the matrix by the addition of core-shell rubber particles or block copolymers, for example. However, the efficacy of these toughening agents in increasing the toughness of these materials is heavily influenced by their ability to produce a coherent microstructure within the epoxy. It was observed that the fracture energy of toughened epoxies, determined via testing on single edge notched beams, decreased with higher cure temperatures. A loss of coherency in the microstructures, as cure temperature increased, was observed via electron microscopy. This was linked to the reduction in toughness enhancements attained as systematically varied resin formulations were cured more rapidly.

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Conference: SAMPE 2019 - Charlotte, NC

Publication Date: 2019/05/20

SKU: TP19--1491

Pages: 13

Price: FREE