Physical Properties of Flexible Polyurethane Foams Manufactured by Varying Toluene Diisocyanate Contents

Polyurethane foams have a wide range of industrial applications. In this study, two types of isocyanates (TDI and MDI) were used in manufacturing the polyurethane foams by varying TDI contents. The cavity diameter of the foams increases with increasing TDI contents, but the cell wall area ratio shows the highest value at 70 wt% TDI content. The cell wall area ratio plays a crucial role in understanding the hysteresis loss and compression stress of the foams. The sag factor and compression set are strongly related to the modulus of the foams depending on the TDI contents. The sag factor decreases but the compression set increases with increasing the TDI contents. These physical properties of the foams are also related to the results of dynamic mechanical analysis under temperature sweep mode.