Low-temperature organic phase change material microcapsules for asphalt pavement: preparation, characterisation and application

Low-temperature phase change material (PCM) is a material that stores additional heat at elevated temperatures and releases energy when the temperature is below the limit. A way to solve the low-temperature disaster of asphalt pavement is desired to be developed. In this article, a two-component organic low-temperature PCM was encapsulated by melamine-urea-formaldehyde resin and finally reinforced with polypropylene. The reinforced PCM microcapsules were mixed with 70# SBS (Styrene-Butadiene-Styrene) modified asphalt in SMA-10 (Stone Matrix Asphalt-10) to form aggregates. The results showed that after adding 6.0% (w/w) reinforced PCM microcapsules, there was a significant delay compared to a blank sample with a maximum temperature difference of 1.8 °C when the temperature dropped to 0 °C, which proved that this method has a good potential in resisting low-temperature disasters on asphalt pavement and deserves further improvement.