Effect of Varying Mixing Ratios and Pre-Heat Temperature on the Mechanical Properties of Polyurethane (PU) Foam

The continuous growth of the usage of Polyurethane foams requires that designers and manufacturers investigate the appropriate factors that affect their production and full usage in order to exploit their full potential. This research reports the effects of the mixing ratio of the main constituents (polyol and diisocyanate) which form the polyurethane foams and different pre-heat temperatures of the separate chemicals before mixing. The work has documented that there is a significant reduction of foaming time of 452 seconds at 20oC to 54 seconds at 100oC when the main constituents are pre-heated before mixing. Both tensile and compressive strengths are improved with increasing the ratio of diisocyanate to polyol. The density of the foam also increases when the concentration of polyol is increased.