AbstractThe dynamic mechanical and tensile deformation and ultimate properties are reported for two epoxy resins in the temperature range, from the glass transitionTgtoTg+ 100°C. The epoxy resins are stoichiometrically reacted diglycidyl ether of bisphenol A with an aromatic (Tg= 115°C.) and an aliphatic (Tg= 47°C.) diamine curing agent. Dynamic measurements were conducted on a rotating cantilever beam instrument over the frequency range from 0.01–100 cycles/sec. Tensile deformation and fracture characterization were obtained by constant rate of strain measurement at strain rates of 0.000445–0.445 sec.−1. Both dynamic and tensile modulus data as well as ultimate stress and strain response superimpose by time and temperature reduction to form unified “master curves.” The time or frequency shift factoraTfor both dynamic and tensile deformation and fracture properties follow the predictions of the familiar Williams‐Landel‐Ferry equation. The rheological and fracture master curves are discussed in terms of both monomer composition and equilibrium response of the crosslinked network. The regions of maximum dynamic dispersion are associated with rubbery state high elasticity tensile response for these epoxies and the magnitude of resp
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