Preparation of palmitic acid/decanoic acid-decanoic acid/cetyl alcohol eutectic mixtures and investigation of phase changing materials (PCMS) properties

In this study, palmitic acid (C16H32O2), decanoic acid (C10H20O2), cetyl alcohol (CH3(CH2) 15OH) and palmitic acid-decanoic acid and decanoic acid-cetyl alcohol eutectic mixtures were prepared. Of these eutectic mixtures having the property of phase-changing material (PCM) prepared in the first step, the thermally and structurally best mixture was determined as the main mixture. In the second stage of the study, a series of insulating materials, which are commonly used, were added to the mixtures with barite, boron nitrite, diatomite and silica fume. Thermal and structural properties of composite PCMs obtained at the last stage were analyzed using DSC, TGA, FT-IR and SEM techniques. Thermal cycling test was also applied to these mixtures. The thermal and structural properties of the mixtures were compared before and after the thermal cycle. Their usability as an insulating material was investigated. According to the comparison of structural and thermal properties, one of the most suitable materials is palmitic acid/decanoic acid eutectic mixture in which diatomite added. The other one is decanoic acid/cetyl alcohol eutectic mixture in which silica fume added. Key Words: PCMs (Phase Change Materials), palmitic acid, decanoic acid, cetyl alcohol, eutectic mixture, barite, boron nitrite, diatomite, silica fume