Preparation and properties of 1-tetradecanol/1,3:2,4-di-(3,4-dimethyl) benzylidene sorbitol gelatinous form-stable phase change materials

A 1-tetradecanol (TD)/1,3:2,4-di-(3,4-dimethyl) benzylidene sorbitol (DMDBS) composite was prepared as a novel form-stable phase change material (PCM), and the properties of the composites such as the gel-to-sol transition temperature, the latent heat, the microstructure and the thermal storage performance were characterized. The composite was prepared by impregnating DMDBS into TD and the maximum feasible weight percentage of TD was determined to be 94.2 wt%. The gel-to-sol transition temperature of the composite PCM was 158.3–180.0 °C, which is well above the melting point of 1-tetradecanol. Differential scanning calorimeter (DSC) was used to determine the melting and freezing enthalpies of 1-tetradecanol in the composite PCM and the values are 218.5 and 215.3 J g−1, respectively. Scanning electron microscopy (SEM) results showed that 1-tetradecanol dispersed in the three-dimensional network formed by DMDBS. The relationship between the amount of DMDBS additive and the leakage was also discussed. The thermal conductivity of the composite PCM was improved by doping with exfoliated graphite.

The 1,3:2,4-di-(3,4-dimethyl) benzylidene sorbitol can self-assemble to form three-dimensional network and immobilized the 1-tetradecanol. As a result, the gel-to-sol transition temperature of the composite PCM increased and the 1-tetradecanol leakage decreased.Figure optionsDownload as PowerPoint slideHighlights
► First used of 1,3:2,4-di-(3,4-dimethyl) benzylidene sorbitol in alcohol-based PCMs.
► A new method of doping with exfoliated graphite is presented.
► A possible mechanism for decreasing leakage has been proposed based on SEM results.
► The prepared composite PCMs showed a high-energy storage density.
► The addition of exfoliated graphite enhanced the thermal conductivity of the PCMs.