Chemorheology investigation of a glassy epoxy thermoset on tensile plastic flow and fracture morphology

摘要: Reproducible and uncharacteristic tensile stress–strain behavior of cured glassy epoxy-amine networks produces distinctive fracture surfaces. Test specimens exhibiting plastic flow result in mirror-like surfaces, whereas samples that fail during yield or strain softening regions possess nominal mirror-mist-hackle topography. Atomic force microscopy scanning electron reveal branched nodule morphologies the 50-nm size scale may be responsible for unusual properties. Current hypothesis is thermoset occurs through existence deformation these nodular nanostructures. The thermal cure profile affects formation nanostructure. Eliminating vitrification polymerization forms a more continuous phase, reduction nodules, eliminates capacity material to flow. This maximizes nanostructure connectivity reduces failure significantly. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Phys. 2015, 53, 1333–1344.