Delphi's TPO-skin instrument panel provides a weight reduction of 10%.
Delphi's recycling process allows for in-plant, closed-loop recycling of 100% offal directly back into the skin.
From the roof frame to the door liners to the upholstery components, numerous applications on the Audi TT utilize Bayer materials.
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A look inside the passenger compartment of virtually any vehicle shows the dominance of plastics, with nearly every solid surface or fabric a polymer. According to experts, the passenger compartment accounts for 56% of the total usage of automotive plastics. The passenger compartment is also the part of the vehicle that traditionally bears the highest assembly costs. The potential advantages of plastics in facilitating component consolidation and modular construction make them attractive interior materials. PVC was once the almost universal surface in car interiors. Although it survives as seals and as fascia coverings in combination with acrylonitrile-butadiene-styrene (ABS) and polyurethane (PUR), it has largely been displaced from seats and door panels. GM has gone so far as to announce its intention to replace PVC on all new vehicle interior panels by 2004, citing its tendency to crack, warp, and fade too quickly. Window fogging has also been a problem with PVC-based material due its plasticizer content.
Traditionally, instrument panels were made from several separate components that needed to be painted and that were all held together by a steel supporting beam that lay behind the panel. Today, thanks to modern plastics technology, instrument panels are made of ABS, ABS/PC alloys, PCs, PP, modified PPE, and styrene maleic anhydride (SMA) resins. The use of these plastics enabled the elimination of the steel support beam in some cases, providing savings of both cost and weight. Wholly integrated single-piece units can be manufactured from all-urethane and all-PP resins for a seamless instrument panel with reduced NVH levels, molded-in color, and cost and weight savings.
Delphi Automotive Systems' TPO skin instrument panel represents a new generation of TPO product technology, an instrument panel skin molded from TPO rather than from a PVC compound. TPO is a material made by combining rubber with PP and has been used in automotive applications for decades. PP is the lightest and lowest-cost form of plastic. Rubberized PP is classified as TPO when the material contains at least 20% rubber.
Delphi applied its TPO skin technology to the upper and lower panels of the 2000 Pontiac Bonneville and the 1999 and 2000 Mercedes-Benz M-Class, providing a panel with a weight reduction of 10%. The product was created by a partnership between Delphi, Mercedes-Benz, toolmaker D&E Corp., and Mytex Polymers, a partnership of ExxonMobil Chemical Co. and Mitsubishi Chemical Corp. Delphi overcame the challenge of offering deep draw capability with TPO, meaning that the material can be vacuum-formed to meet complex shape and contour demands. The material enables hidden airbag doors without seam read-through and airbag deployments without fragmentation at low temperatures.
Delphi uses water-based primer and topcoat systems on its TPO components, reducing ozone-forming volatile organic compound emissions. Delphi's process for the TPO-skin manufacturing allows for in-plant, closed-loop recycling of 100% offal directly back into the skin.
When P.L. Porter Co. switched from metal to composite components on its automotive seat-reclining mechanism, the firm chose for its swing arm component Verton RF, a long glass-fiber-reinforced nylon 66 structural composite from LNP Engineering Plastics, that had the necessary compressive and tensile strength. A swing arm component is the seat-reclining mechanism actuated by a handle on the side of the car seat. It is a locking device that allows passengers to move the seat back and forth, and must be made of a high-strength material to support normal loads, as well as extra loads such as someone stepping on the handle. In a two-door car or truck, a lever is actuated to dump the seat forward to enable passengers to climb into the back seat. For the dump lever component, the firm chose Lubricomp RFL, a glass-fiber-reinforced lubricated nylon 66 composite also from LNP. The nylon dump lever has an internal lubricant that reduces friction and wear rates. By using the two composites, P.L. Porter was able to incorporate the seat dump within the reclining mechanism for about a third of the cost of the original part.
In the interior of the Audi TT, plastic components create the link between aesthetics and functionality. The door liners are made from the ABS polymer Lustran 2443 developed by Bayer specifically for this application. Because of its good flow properties, the complex geometries of the door trim panels were produced economically and without problem by injection molding. Indentations, handle recesses, openings for switches and speakers, and the various fastening elements could all be directly integrated. The manufacturer of the moldings is Seeber Systemtechnik KG. Due to its high-impact strength, the thermoplastic lining is unlikely to splinter, reducing the risk of injury to the driver and passengers in the event of a side impact. The material also bonds well with standard solvent-based and solvent-free laminating adhesives that are used to fix decorative facings. The center console of the TT is also made of Lustran, injection molded by Peguform Bohemia.
The A- and C-pillars and the roof frame are made of Bayblend, Bayer's PC-ABS blend. This plastic is noted for its consistent mechanical properties at low wall thicknesses. Polyurethane foam padding made of Bayer's Bayfill EA and produced by Thieme is built into particularly critical areas of the A- and C-pillars, the rear section of the roof, and the rear side-trim panels. In the event of a crash, force absorption by the padding is more or less equal over a wide deformation range so that even low component thicknesses will absorb impact energy.
The upholstery components of the seats in the Audi TT are made of Bayer's flexible polyurethane molded foam, Bayfit HR-T. The properties of Bayfit enable foams of different hardness to be produced to improve seating comfort and driving safety. The front seat cushions can be given side zones with higher stability to enable safer driving around corners, and make it easier for people to get in and out.
