ABSTRACT
Polyurethane foam has been the material of choice for automotive seat cushions for over thirty years. Worldwide, this material is broken down into four main technologies: TDI-HR, TDI/MDI-HR, MDI-HR, and TDI-Hot Cure foam. There has been much discussion recently as to which technology is best for seat comfort and durability. These technologies have been compared in past publications, but in most cases, comparisons were not made at the same hardness and density. This type of comparison often results in misleading conclusions.
In this study, foams of different technologies were systematically prepared at equivalent density and hardness targets. The hardness/density grades were chosen based on typical industry targets. These various foam grades were subject to a battery of durability, comfort, and physical property tests. Results were analyzed and correlations developed.
The results showed that no one technology meets all criteria over all foam grades. Moreover, within certain density/hardness grades, the differences in performance between technologies were small. In addition, in many cases the results were more dependent on foam density and hardness than on the technologies that were used. Each technology had its strengths and therefore the selection of appropriate technology should be made based on the specific criteria that are trying to be met.
