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In this study, form-stable tetradecanol (TD)/expanded perlite (EP) composites by adding Cu powder (CuP) and carbon fiber (CF) to enhance thermal conductivities have been prepared via vacuum impregnation method. The thermal conductivity enhancer (TCE) is introduced by two methods of mixing TCE with phase change materials (PCMs) and implanting TCE into matrix materials. The result demonstrates the former is better than the latter in aspects of thermal property, thermal conductivity and controllability, moreover, adding ratio of TCEs gather in more appropriate interval from 2.5% to 3% suitable for the former. For CPCMs, FT-IR results indicate it is no chemical interaction among raw materials but physical combination via two methods. CPCMs prepared by the method of mixing TCE with PCMs have better phase change latent heat and thermal stability by DSC and TGA, while thermal cycling measurements show that form-stable composite PCMs have adequate stability even after being subjected to 200 melting/freezing cycles. Therefore, the method of mixing TCE with PCMs has better thermal property and controllability than that of implanting TCE into matrix materials and the prepared CPCM has great application prospect in solar energy utilization, building material, indoor cooling instrument and so on for thermal energy storage.

Lightweight wall material (LWM) composited with EG/paraffin composite was prepared by experimental procedures of foaming, slip casting and constant temperature curing. The EG/paraffin composites were synthesized via vacuum impregnation method. The scanning electron microscope (SEM) analysis indicated that paraffin was sufficiently absorbed into the EG porous network and depicted no leakage even in the molten state. The X-ray diffractometer (XRD) and Fourier transformation infrared spectroscope (FT-IR) results revealed that paraffin and EG in the composite didn’t undergo chemical reactions but only physical combination. The compressive strength value of the sample reached 2.853 MPa, while bulk density reduced to 0.445 kg/m 3 . The differential scanning calorimeter (DSC) results revealed that the sample melts at 47.78 °C with a latent heat of 16.26 J/g and solidifies at 43.81 °C with a latent heat of 15.98 J/g. The sample with 15% EG/paraffin composites had adequate stability by contrasting mechanical property and DSC profiles before and after 200 times thermal cycles. Furthermore, the thermal conductivity of the LWM increased to 0.76 W (m K) when 20% EG/paraffin was added into the composite. This indicates that the prepared sample has a good thermal property. Hence, the LWM containing EG/paraffin composite would be useful as thermal energy storage material.