Preparation and thermal properties of some mixtures of fatty acids and liquid paraffin as PCMs used for energy-storing wallboard

Abstract

Mixtures of liquid paraffin and stearic acid, myristic acid, lauric acid and palmitic acid were prepared and investigated. The thermal properties of several mixtures were studied experimentally by a differential scanning calorimeter. The experimental results show that the phase-change temperatures and the phase-change latent heats of mixtures decrease with the increasing mass content of liquid paraffin. The phase-change temperatures of mixtures of liquid paraffin and palmitic acid, myristic acid and stearic acid are more than 30 °C, so they are not suitable for wallboard. When the mass contents of liquid paraffin are 60–80%, the phase-change temperatures of the mixture of liquid paraffin and lauric acid are 20.7–28.6 °C and the phase-change latent heats are 35–90 J/g. So mixtures of liquid paraffin and lauric acid are suitable phase-change materials (PCMs) used for wallboard. The results in this paper can provide references and a basis for the application of PCMs in wallboard.