Microstructures and toughening mechanisms of organoclay/polyethersulphone/epoxy hybrid nanocomposites

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 528; no. 27; pp. 7999 - 8005
• Main Authors: Wang, Yang, Zhang, Boming, Ye, Jinrui
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.10.2011; Elsevier
• Subjects: Applied sciences; Composites; Exact sciences and technology; Forms of application and semi-finished materials; Fracture mechanics; Fracture toughness; Hybrid nanocomposites; Mathematical analysis; Matrices; Matrix methods; Microstructure; Nanocomposites; Nanomaterials; Nanostructure; Organoclay; Polymer industry, paints, wood; Technology of polymers; Toughening mechanism; Hybrid nanocomposites; Toughening mechanism; Organoclay; Fracture toughness; Strengthening; Organic clay; Sulfone polymer; Ductility; Epoxy resin; Plastic deformation; Crack propagation; Crack bridging; Nanocomposite; Microstructure; Fractography
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2011.07.009

[Display omitted] ► Epoxy resin is synergistically toughened by polyethersulphone and organoclay. ► Hybrid nanocomposites have homogeneous matrices and ordered exfoliated nanolayers. ► Organoclay toughens epoxy resin from micron-scale to nanoscale. ► Orientation is critical for nanolayers to cause crack to bifurcate and deflect. Hybrid nanocomposites (HNCs) with high fracture toughness were successfully prepared by incorporating polyethersulphone (PES) and organoclay into epoxy resin. Their microstructures were studied. They were composed of homogeneous PES/epoxy matrices and micron-scale organoclay agglomerates. These agglomerates consisted of smaller tactoid-like regions which were comprised of ordered exfoliated nanolayers. The toughening mechanisms of the two tougheners were also studied and then related to their microstructures. For one thing, the PES which was dissolved in the epoxy resin homogeneously improved the ductility of the epoxy resin and made it easier to deform. For another, the organoclay agglomerates induced crack front bowing, crack bridging, crack deflection, crack bifurcation and plastic deformation of the matrices on the micron-scale, respectively. These toughening processes were achieved by the ordered exfoliated nanolayers with various orientations, which debonded from the matrices, bridged the cracks and induced the plastic deformation of the matrices on the nanoscale.