Dynamic and mechanical studies of diglycidyl ether of bisphenol A (DGEBA) based epoxy resins cured with a mixture of two curing agents have been performed. One of the components of the mixed curing agent was an aromatic amine, m-phenylene diamine (mPDA), and the other was a poly(propylene oxide) based amine (Jeffamine D-230 or T-403). The mPDA content was changed in the 0-100 wt% range of the curing agent. Glass transition temperatures varied linearly as a function of the mPDA content in the curing agent and they increased with the crosslink density of the cured networks. Although a low amount of aliphatic amine lowered the rigidity of the mixture cured with mPDA, it resulted in an evident increase in resistance and toughness of the mixture, thus showing the potential interest of these systems for practical applications.