WEB EXCLUSIVE: BMW Group is the world’s first car maker to use PP expandable-bead foam as a visible contour material on a center console. Neopolen P EPP foam from BASF, Florham Park, N.J., played a key role in this joint project which resulted in first-place 2013 SPE award in the Body Interior category.
Neopolen P foam reportedly helps reduce weight by around 30% compared with the previous solution. The foam also boasts very good noise insulation and high thermal resistance. The particle foam combines high energy absorption—even after multiple impact loads, with good resilience and isotropic deformation performance. Molding technology specially developed for this purpose is said to eliminate steps otherwise necessary for the conventional process, so that production now consists of a single step. This foam also allows integration of additional functions into the center console. For example, the molding process can provide for ventilation channels for the air-conditioning system serving the rear of the car’s interior.
The one-step process begins with laying of thermoplastic substrate into the mold, filling its cavity with foam beads, and using steam pressure to weld these two elements into a molded part. Also during this step, movable bars place smooth sheeting on the molded part and firmly bond it with the material. At the same time, the bars’ grain structure and the heat from the steam lend the sheeting its texture for an appealing surface with a softer feel. BMW Group will be selecting the models to use this lightweight structural element in future production.