Improving Thermal Properties of N-Nonadecane/Expanded Dolomite Composite Phase Change Material for Thermo-Regulating Textiles

Abstract

This paper mainly addressed preparation of a new n-nonadecane/expanded dolomite (ED) composite using vacuum impregnation method. This method was first used for textile thermal protection. In this method, n-nonadecane was applied as the phase change material (PCM) and ED was used as the supporting material in order to prepare and construct form-stable composite PCM. Composite properties were determined by FTIR and SEM techniques. Also the heat transfer measurement and differential scanning calorimetric (DSC) test were used to determine the thermal properties of composite on fabrics. The DSC results showed that freezing and melting temperatures of n-nonadecane in composite PCM have changed a little, indicating that there are no strong interactions between n-nonadecane molecules and the pore walls of ED. It was found that moisture transfer properties have substantial effects on textiles comfortable attributes. That is why moisture transfer properties were measured; the results show that the more fabric pores have been filled in composite PCM, which these changes cause moisture transfer reduction. The SEM results showed that the PCM was well absorbed in the porous network of the expanded materials. The results for DSC and temperature transfer also suggested that fabric temperature range for the amount of coated PCM depends on its area; namely, the more PCM is used in the fabric, the more heat for temperature increase will be needed. This is because as PCM increases in the composite, the latent heat storage density increases too; further, by adding n-nonadecane/ED composite to the textile surface; moisture and thermal transfer could be reduced.