The Contribution of Molded Polyurethane Foam Characteristics to Comfort and Durability of Car Seats 1999-01-0585
The major element of contact between the occupant, the vehicle and the road surface is the automobile seat. Flexible polyurethane foams are the material of choice for this application, not only because of the economies offered by large-scale molding operations, but also because the cushioning characteristics of the foam/seat assembly can be adjusted. The automotive original equipment manufacturers (OEM’s) worldwide are looking for optimization of the balance between foam weight and foam specifications, with more emphasis than ever on comfort and durability. This goes with specific requirements for the various foam pads, i.e., front cushion, rear cushion, front backrest and rear backrest.
Commercially useful foams can be made from a variety of polyurethane molding chemistries. To meet the wide range of performance targets, foam producers utilize four basic foam chemistries in production scenarios that vary widely in regards to dispensing equipment, molds and overall processing conditions.
In this paper, we present new data assessing the relative influence of formulation and processing variables on the performance of foam pads molded from each of the major chemistries. Specific data demonstrating how comfort and durability parameters vary with choice and level of polyol, copolymer polyol (CPP), isocyanate and other chemical components are presented.
Using industry standard tests, results comparing resilience and vibration damping, as well as dynamic fatigue under various combinations of temperature and humidity are presented. It is expected that the results of this study will help foam producers and seat assemblers in their efforts to further improve the in-car performance of seats based on molded flexible polyurethane foams.
Citation: Casati, F., Berthevas, P., Herrington, R., and Miyazaki, Y., "The Contribution of Molded Polyurethane Foam Characteristics to Comfort and Durability of Car Seats," SAE Technical Paper 1999-01-0585, 1999, https://doi.org/10.4271/1999-01-0585. Download Citation
F. M. Casati, P. R. Berthevas, R. M. Herrington, Y. Miyazaki
The Dow Chemical Company
International Congress & Exposition
SAE 1999 Transactions - Journal of Materials & Manufacturing-V108-5