Utilization of paraffin/expanded perlite materials to improve mechanical and thermal properties of cement mortar

• Paraffin has good compatibility with expanded perlite.
• The optimal cement of paraffin/expanded perlite materials in cement mortar is determined as 20 wt%.
• The heat storage/release curves of cement mortar with paraffin/expanded perlite materials changed slightly after 100 cycles.
• Cement mortar with 20 wt% paraffin/expanded perlite materials has good heat storage and thermal stability.

In this study, cement mortar with paraffin/expanded perlite materials was prepared by direct mixing method. The effect of paraffin/expanded perlite material content on mechanical and thermal properties of cement mortar were investigated. The experimental results showed that the paraffin was confined in the porous structures of expanded perlite by capillary force. The average mass percentages of paraffin in paraffin/expanded perlite material reached as high as 65%. It was a physical interaction between paraffin and expanded perlite. Compressive strength and flexural strength of cement mortar decreased with increasing amount of paraffin/expanded perlite materials. Cement mortar with 20 wt% paraffin/expanded perlite materials had good heat storage property and thermal stability compared to ordinary cement mortar.