Composite phase change materials of ultra-high molecular weight polyethylene/paraffin wax/carbon nanotubes with high performance and excellent shape stability for energy storage

作者：Cao, Xianwu; Li, Chunnong; He, Guangjian; Tong, Yizhang; Yang, Zhitao^*

来源：Journal of Energy Storage, 2021, 44: 103460.

DOI：10.1016/j.est.2021.103460

• Ultra-high molecular weight polyethylene
• Composite phase change materials
• Energy storage
• Carbon nanotubes
• Microwave sintering

Ultra-high molecular weight polyethylene (UHMWPE)/carbon nanotubes (CNT) porous skeleton was prepared by microwave sintering, then paraffin wax (PW) was absorbed into UHMWPE/CNT porous skeleton by vacuum, obtaining composite phase change materials (CPCM). Differential scanning calorimetry (DSC) results showed that with CNT content of 1.5%, the PW adsorption of CPCM reached 59.91% and latent heat of the CPCM hardly changed after 20 melting/freezing cycles. Furthermore, thermal conductivity of porous matrix and CPCM from 0.1858 and 0.3012 W m (-1) K (-1) to 0.3272 and 0.4225 W m (-1) K (-1) with the CNT content increased (from 0% to 2%), respectively. In addition, the CPCM had a great shape stability. When the temperature reached 70 degrees C, PW in CPCM hardly leaked. In the photothermal conversion, CPCM realized the function of energy storage and release. Therefore, the CPCM prepared by a facile and environmentally friendly strategy with high energy storage efficiency, outstanding thermal repeatability, excellent thermal stability and high thermal conductivity had a broad prospect in the application of energy storage.