Thermal cycle test of binary mixtures of some fatty acids as phase change materials for building applications

• Thermal cycle tests conducted for binary mixtures based on fatty acids for building applications.
• The melting temperature of materials is in the desired range of 21–30 °C.
• The latent heat of fusion is in the range of 100–170 kJ/kg.
• The PCMs had enough potential to recommend for building applications.

This paper deals with the thermal cycle tests of the binary mixtures based on fatty acids, i.e. capric acid (CA), lauric acid (LA), myristic acid (MA), palmitic acid (PA) and stearic acid (SA). Overall, 13 binary mixtures, i.e. CA–LA (40/60 wt.%, 50/50 wt.%, 60/40 wt.%, 70/30 wt.% and 80/20 wt.%), CA–MA (70/30 wt.%, 80/20 wt.% and 90/10 wt.%), CA–PA (70/30 wt.%, 80/20 wt.% and 90/10 wt.%) and CA–SA (60/40 wt.% and 90/10 wt.%) were developed as latent heat energy storage materials for the building applications. The Differential Scanning Calorimetry (DSC) technique was applied to the binary mixtures after 0, 50, 100, 150, 200, 250, 300, 600, 900, 1200 melt/freeze cycles to measure the melting temperatures and the latent heats of fusion. The DSC results showed that the changes in melting temperature were in between −1.69 °C to 4.33 °C, and the changes in the latent heat fusion was −35% to +25%. These results show that the melting temperatures and latent heat values of the PCMs are in the range of about 21–30 °C and 100–170 J/g which showed that these materials have good thermal stability up to 1200 thermal cycles and can be potentially applied for building applications.