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Graphical abstract Highlights • An industrially-applicable and simple method to develop latent accelerators. • A one-pot system with at least 4 months shelf life. • This latent accelerator lowered the epoxy/dicyandiamide curing onset temperature to 130 °C. Abstract One-pot epoxy system is widely used in prepreg applications. Achieving a long storage life and at the same time, a low curing temperature is a real challenge in one-pot systems. To deal with these challenges, we developed adducts as latent accelerators for one-pot epoxy/dicyandiamide system through the addition reaction of epoxy, phthalic anhydride and different types of alkanolamine/phenol amines. Fourier transform infrared spectroscopy (FTIR), 13C nuclear magnetic resonance spectroscopy (NMR) and thermogravimetric analysis (TGA) showed that the so-prepared adducts were long chain tertiary amines. Non-isothermal differential scanning calorimetry (DSC) proved the effectiveness of adducts towards significant reduction of the curing peak temperature of epoxy/dicyandiamide. The analysis of variance (ANOVA) revealed that the acceleration capacity is controlled by adduct ingredients of amine type, amine and phthalic anhydride content. The activation energies (E α) projected by isoconversional methods revealed different E α - conversion profiles for each system that were in agreement with chemorheological results. According to Málek method, Šesták–Berggren model was the most appropriate to fit the experimental reaction rates. Furthermore, for all one-pot epoxy/dicyandiamide samples, no viscosity build-up and epoxide group consumption were detected after 4 months indicating for their relatively long shelf lives. [ABSTRACT FROM AUTHOR]