Effective Encapsulation of Paraffin Wax in Carbon Nanotube Agglomerates for a New Shape-Stabilized Phase Change Material with Enhanced Thermal-Storage Capacity and Stability

Seeking new applications of carbon nanotubes (CNTs) will be important since large-scale production has made them available in many applications. Herein, aggregated CNTs (A-CNTs) with interwoven pores were prepared for shape-stabilized phase change materials (PCMs). Owning to the capillary force from the pores, paraffin was readily encapsulated into A-CNTs, and formed a new kind of shape-stabilized PCMs. As-prepared paraffin/A-CNT composites had optimal paraffin loading approaching 88 wt % and offered a storage capacity of 172.14 J g(-1) that exceeded the vale based on mixing rule. To confirm the structure effectiveness, A-CNTs were dispersed into random nanotubes; as-formed composite PCMs displayed obviously reduced loading and storage capacities. The enhanced performance was ascribed to the effective encapsulation of paraffin in the interwoven pores of A-CNTs. Moreover, the composites with improved thermal conductivities were attained and displayed enhanced thermal-storage response. The results indicated that as-prepared composites were promising candidates for thermal management systems.