Properties of epoxy-resin binders and feasibility of their application in pavement mixtures

Abstract

Epoxy resins have the potential to solve the limitations faced by traditional pavement materials while meeting strict environmental regulations. In this study, taking into account the performance and structural differences of different epoxy resins, curing agents, and tougheners, we designed an optimized combination of materials that can be cured at room temperature and exhibits good low-temperature toughness. To this end, we used glass-transition temperature (Tg) as an index to design the material ratio. After synthesizing an epoxy-resin binder with a Tg of −10 °C, its curing characteristics and mechanical properties were studied. Furthermore, epoxy-resin pavement mixtures (ERPMs) were designed using this binder and its curing age, high-temperature and low-temperature characteristics, and water stability were evaluated. The results show that the epoxy-resin binder synthesized using hydrogenated bisphenol A epoxy resin AL-3040, toughener A, and polyamide 650 exhibited good workability and mechanical properties and hence is suitable for pavement mixtures. The mass ratio of the toughener to resin significantly affected the low-temperature tensile properties of the binder and the direct tensile-property of epoxy resin binder was basically unchanged with the isothermal conditioning time. The prepared ERPM exhibited good high-temperature stability, low-temperature crack resistance, and water stability, and its performance metrics were better than those of standard asphalt mixtures. Changes occurring in the binder viscosity during solidification can be used to determine the optimal parameters for ERPM preparation. Finally, the results described in this study are expected to promote the application of ERPMs in road construction and maintenance.