Effect of polyethylene glycol/polyacrylamide graft copolymerizaton phase change materials on the performance of asphalt mixture for road engineering

It is significant to make full use of solar energy to reduce the deterioration of asphalt pavements and the negative impact on the environment due to temperature changes. Using phase change materials (PCMs) in asphalt mixture could increase temperature regulation and reduce thermal degradation due to temperature cycling. In order to study the effect of a new solid–solid PCM called PPGC-PCM on the performance of asphalt mixture, a series of tests were carried out. The control group and six different contents of PPGC-PCM were added into AC-13 asphalt mixtures. The effects of PPGC-PCM on the mechanical, moisture resistance, high-temperature, and low-temperature cracking resistance properties of asphalt mixture was analyzed. The influence of PPGC-PCM on the thermal properties in asphalt mixture was analyzed by thermal conductivity test. Results showed that the addition of PPGC-PCM could improve the moisture resistance and low-temperature cracking resistance of asphalt mixtures, as well as greatly reduce the thermal conductivity of the asphalt mixture. The optimal application could be achieved by using the PPGC-PCM with 7.5% addition ratio. In addition, the cooling test proved that the addition of PPGC-PCM could significantly improve the heat preservation capacity of the asphalt mixture. The temperature difference between PPGC-PCM and control testing groups was up to 3.8°C, and the mixture was cooled from 21°C to 0°C with a delay of 18–21 min.