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A new cross-linked shell microencapsulated phase change materials (MEPCMs) were prepared by interfacial polymerization, and butyl stearate and polyurethane was empolyed as core material and shell material respectively, while polyurethane shell was reacted by isophorone diisocyanate (IPDI), diethylene triamine (DETA) and pentaerythritol. The surface morphology, chemical structure, phase change properties and thermal stability of MEPCMs were investigated by SEM, FTIR, DSC and TGA. The results show that the prepared microcapsules are sphere with smooth and compact surface, and have good thermal storage properties. When pentaerythritol was employed, the thermal stability and compactness of the cross-linked polyurethane shell MEPCMs has been greatly improved compared to that of linear polyurea shell MEPCMs. When the continuous drying time point is at 120 °C for 5 h, the weight loss of cross-linked MEPCMs was only 4.65%. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports a study on the thermal stability of phase change material microcapsules that are incorporated with silver nano-particles (Ag-NPs). The novel microcapsules were fabricated by the technique of in situ polymerization, with aminoplast as the wall and phase change material bromo-hexadecane (PCM BrC16) as the core. Thermal gravimetry (TG) analysis was applied to measure the thermal stability of these microcapsules and surface morphology of the microcapsules was observed by means of scanning electron microscopy (SEM) after an application of curing treatment at 130°C. Comparing with conventional phase change material microcapsules (PCMMs), nano-composite phase change material microcapsules (NCPCMMs) have higher thermal stability. This can be attributed to nano-composite structure of the microcapsules, in which metal Ag-NPs distributed on the surface to increase wall toughness and strength. The possible reinforcement mechanisms of the nano-composite structure are explored. [Copyright &y& Elsevier]