Intercalated clay nanocomposites: Morphology, mechanics, and fracture behavior

TLDR

Intercalated montmorillonite clays were incorporated into a glassy epoxy via aliphatic diamine crosslinking, and fracture surfaces were characterized by SEM and AFM to link morphology to mechanical behavior. The composites exhibited higher Young’s modulus but lower ultimate strength and strain, unchanged compressive behavior with altered failure modes, and a 100 % increase in fracture toughness compared to the unmodified resin. © 2001 John Wiley & Sons, Inc., J Polym Sci B: Polym Phys 39:1137–1146.

Abstract

Abstract Intercalated nanocomposites of modified montmorillonite clays in a glassy epoxy were prepared by crosslinking with commercially available aliphatic diamine curing agents. These materials are shown to have improved Young's modulus but corresponding reductions in ultimate strength and strain to failure. The results were consistent with most particulate‐filled systems. The macroscopic compressive behavior was unchanged, although the failure mechanisms in compression varied from the unmodified samples. The fracture toughness of these materials was investigated and improvements in toughness values of 100% over unmodified resin were demonstrated. The fracture‐surface topology was examined using scanning electron and tapping‐mode atomic force microscopies and shown to be related to the clay morphology of the system. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 1137–1146, 2001