کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
674191 | 1459553 | 2012 | 6 صفحه PDF | دانلود رایگان |
Di-n-hexylammonium bromide ((n-C6H13)2NH2Br) undergoes a solid–solid phase transition at about 20 °C. The fact that it remains as a solid phase, yet the transition has a rather large enthalpy change (85 J g−1) suggests possible advantages as a phase change material (PCM) for integration into building materials. We investigated the phase change of (n-C6H13)2NH2Br in its pure form, and as a 30 mass% composite in gypsum. In the latter, we show that after 1000 cycles, which would correspond to about 3 years of use as a solar energy storage material, the temperature of the transition changes by less than 1 K and the enthalpy of transition is reduced by less than 3%. We also report the heat capacity and thermal conductivity of (n-C6H13)2NH2Br in the temperature range below and above the phase transition, and the volume change associated with the transition.
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► The thermal properties of (n-C6H13)2NH2Br across its solid–solid phase change have been characterized.
► (n-C6H13)2NH2Br shows good long-term stability of its phase transition over 1000 thermal cycles, even when incorporated in gypsum.
► We find that (n-C6H13)2NH2Br shows excellent potential for use of its solid–solid phase transition for heat storage and recovery.
Journal: Thermochimica Acta - Volume 531, 10 March 2012, Pages 54–59