Preparation and characterization of soy polyols‐based PU shell microencapsulated phase change materials for reliable thermal energy storage

Abstract

Summary Microencapsulated phase change materials (MEPCMs) have attracted extensive attention due to their ability to encapsulate and protect core materials. Herein, this paper presents the successful preparation of an environmentally friendly bio‐based polyurethane (PU) by utilizing soy polyols as raw material and utilizing it innovatively to achieve the microencapsulation of phase change materials (PCMs). The surface morphology, thermal properties, particle size and particle size distribution of MEPCMs were comprehensively characterized and analyzed. Especially, a systematic study was conducted on MEPCMs in terms of their structure and properties, depending on different preparation conditions. According to the results, microcapsules obtained with a core‐shell ratio of 1:1 and mechanical stirring speed of 300 rpm display good spherical shape, smooth surface, and narrow particle size distribution. Moreover, the melting enthalpy of microcapsules can reach 91.4 J/g when the core material content is 48.4%. Moreover, compared to pure paraffin, the prepared microcapsules have superior thermal stability and high reliability, which shows promising energy storage efficiency of 91.5% even after 50 hot‐cold cycles.

Microencapsulation of Phase Change Materials with a Soy Oil-Based Polyurethane Shell via Pickering Emulsion Polymerization

“…Pickering emulsions are required to achieve a stable state under the dual action of M-SiO 2 and mechanical stirring . We investigate in this paper the variation in performance of MEPCMs by changing the stirring speed during preparation.…”

“…Pickering emulsions are required to achieve a stable state under the dual action of M-SiO 2 and mechanical stirring. 34 We investigate in this paper the variation in performance of MEPCMs by changing the stirring speed during preparation. The microscopic pictures of MEPCMs obtained at various stirring speeds are shown in Figure 3a−d. As shown in the figure, the particle size of MEPCMs reduces along with increasing stirring speed in the range of 200−500 rpm.…”

Phase Change Composite Microcapsules with Low-Dimensional Thermally Conductive Nanofillers: Preparation, Performance, and Applications

“…In particular, the initial reaction rate between diisocyanate and polyol is relatively lower, and the elasticity of MEPCMs shell can be improved by adjusting the soft segment structure of PU, which is very beneficial to the mechanical properties and compactness of MEPCMs [ 62 ]. Therefore, in the previous study, our team has realized the microencapsulation of methyl laurate with PU shell through interfacial polymerization [ 63 , 64 , 65 ]. In addition, some polymers including polystyrene (PS) [ 66 , 67 , 68 , 69 , 70 ] and starch [ 71 ], etc are also used as organic shell materials to prepare MEPCMs.…”