Low-Temperature Phase-Change Microcapsules for Modified Asphalt Binder: Preparation, Characteristics, and Performance Evaluation

Low-temperature phase-change microcapsules (MPCMs) are environmentally friendly materials that have been used as a modifier for improving the low-temperature performance of asphalt binder. However, there are some problems with the production and application of MPCMs, i.e., difficult preparation procedures and undefined effects on the properties of asphalt binder. In this study, the impact of resin-shell material synthetic melamine–urea–formaldehyde and core materials n-tetradecane on the properties of MPCMs and corresponding modified binders have been investigated, respectively. The results showed that the largest latent heat of microcapsules was 117 J/g with the optimized preparation parameters of MPCMs (10% emulsifier concentration, 3,000/rpm emulsification speed, core/wall mass ratio of 1:1, oil/water ratio of 1:10, 120 min reaction time, 75°C synthesis temperature). Based on the optimized parameters, the exothermic and heat absorption ranges of MPCMs were from −5°C to −20°C and 0°C to 20°C, respectively. After using MPCMs, the modified binder had a higher enthalpy latent heat of 5.1 J/g without any other affects. This study identifies the using potential application value of the temperature-changing modified binder for the anti-icing and temperature regulation pavement.