Dynamic mechanical properties of nonstoichiometric, amine‐cured epoxy resin

The dynamic mechanical properties of epoxy resins cured with nonstoichiometric amounts [37%–103% of stoichiometric composition (SC)] of diethylenetriamine at room temperature have been measured in the temperature range 85° to 300°K and correlated to structures of cured resins. The dynamic mechanical behavior changed above and below 62.5% of SC, at which network structures are formed. The intensities of γ‐ and β‐peaks, ∼150° and ∼250°K, respectively, depend upon the concentration of DETA used. The processes of the γ‐ and β‐peaks are discussed.