The influence of nano‐silica on the thermal conductivity of polyurethane foam

Abstract

Abstract This study reports the influence of nano‐silica particles (0.0–0.45 %wt) on properties of polyurethane foams (PUF) using monoglycerides, sorbitol, and glycerol as components of polyol. The morphology, density, mechanical, thermal stability, and thermal conductivity properties of samples were investigated in this study. When 0.35 %Wt of nano‐silica was used to reinforce PUF, the compression strength of PUF achieved the highest value (82.49 kPa). The thermal gravimetric analysis showed that the presence of nano‐silica can improve the thermal stability of PUF samples. Scanning electron microscopy studies indicated that PUF samples containing 0.3, 0.35, and 0.45 %Wt of nano‐silica had more uniform cell structures than pure PUF sample. Finally, the thermal conductivity of pure PUF and PUF/nano‐silica were measured at three different levels of humidity (33% RH, 57% RH and 75% RH) at 25°C. The lowest thermal conductivity value achieved was 0.034 W/mK.