Preparation and performance evaluation of phase-change microcapsules and performance analysis of phase change asphalt
In this study,the impact of phase-change microcapsules(PCM)on asphalt performance was investigated through a series of orthogonal experiments.These experiments focus on the evaluation of the effect of the urea-formalde-hyde(melamine-urea-formaldehyde)resin as a shell material and n-tetradecane as a core material on the synthetic efficien-cy of PCM.The optimal preparation process for PCM was analyzed.Differential scanning calorimetry and dynamic shear rheology were employed to assess the performance of the PCM-modified asphalt(referring to as phase change bitu-men).The findings indicated that the most effective synthetic parameters were determined for PCM at an emulsifier con-centration of 7 wt.％,an emulsification speed of 2 000 r/min,a mass ratio of core to wall material of 1∶1,a 1∶7 oil-to-water volume ratio,a synthetic time of 90 min,and a reaction temperature of 80 ℃.Under such conditions,PCM exhib-ited a latent heat of 117 J/g.Furthermore,the microcapsule shell presented excellent sealing properties,ensuring the sta-bility of asphalt within the range required for construction temperature.The PCM-modified asphalt showed an exother-mic interval from-7.1 to-17.9 ℃ and an endothermic interval from 2.3 to 13.5 ℃.The PCM-modified asphalt pre-sented a phase-change enthalpy of 5.1 J/g at a microcapsule concentration of 7 wt.％.More importantly,the incorpora-tion of PCM effectively slowed down the hardening process of the PCM-modified asphalt and maintained its stability at room temperature.The developed phase-change asphalt exhibits great potential for application.
万方数据
维普
