Mechanical and Fractrographic Studies on Fly ash-filled Hydroxyl-terminated Polyurethane-toughened Epoxy Composites

Abstract

Thermoplastic hydroxyl-terminated polyurethane (HTPU) elastomer in different proportions (1, 2, 3, 4, and 5 wt%) was incorporated into DGEBA-based epoxy resin and cured with triethylene tetramine. The several matrices involved were subjected to mechanical strength analysis, and among the combinations of blend matrices studied, the one that showed highest strength, namely, 1 wt% of HTPU in epoxy, was chosen to prepare composites. Mechanical properties of pure epoxy and HTPU-toughened epoxy composites filled with fly ash were studied with respect to varying weight fractions of fly ash loading. In this article, the mechanical properties studied are compression and impact. Fractographic studies of the toughened resin matrix and its composites have been carried out using scanning electron microscopy.

Keywords

epoxy resin hydroxyl-terminated polyurethane composites fly ash fractographic studies.

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