Fabrication and investigation of paraffin based shape-stable composite phase change materials with styrene ethylene butylene styrene as supporting skeleton for low temperature thermal energy storage and management

Paraffin based composite phase change materials (PCMs) have gained intensive attentions in low temperature thermal energy storage (TES) and management application domains because of its suitable melting temperature range and advanced thermoproperties. Seeking decent structural supporting materials (SSM) and the associated manufacturing approaches that capable of fabricating paraffin composites at appropriate temperatures to avert the thermal decomposition of the paraffin particularly for low-molecule ones are in high demand. Herein, we developed a low-molecule paraffin (RT18HC) composite through a simple blending approach by using styreneethylene/butylene-styrene (SEBS) as SSM, and showed that such SEBS-paraffin composites could be able to fabricate at a low operation temperature of 80 degrees C, significantly lower than that required for the preparation of conventional high density polyethylene (HDPE)-paraffin composites. To enhance the composite effective thermal conductivity, a micro-sized graphite power as enhancer was also involved over the fabrication process. Owing to the desirable solubility of paraffin in SEBS, a crosslinking structure inlaying paraffin and graphite was formed, endowing the composite with ability to maintain the structure stabilization and eliminate the graphite sedimentation over the repeated thermal cycles. 10 wt% of SEBS gives the composite optimum formulation at which 10 wt% graphite can be involved, and also an excellent shape stability and thermal adjustment ability can be achieved.

Automated summary

This study developed a low-molecule paraffin (RT18HC) composite using a simple blending approach with styrene-ethylene/butylene-styrene (SEBS) as the structural supporting material. The SEBS-paraffin composites could be fabricated at a low operation temperature of 80 degrees C, significantly lower than the temperature required for conventional HDPE-paraffin composites. Micro-sized graphite powder was added to enhance the thermal conductivity of the composite. The solubility of paraffin in SEBS allowed the formation of a crosslinking structure embedding paraffin and graphite, which maintained the structure stability and eliminated graphite sedimentation over repeated thermal cycles. 10 wt% of SEBS provided the optimum formulation, allowing the inclusion of 10 wt% graphite and achieving excellent shape stability and thermal adjustment ability for the composite.