Borealis creates new zero-gap Daplen™ grades for BMW Series 1 bumpers and rocker panels

BMW Group, seeking a zero-gap thermoplastic for its BMW Series 1 bumpers and rocker panels, turned to Borealis to create a material for its needs. BMW wanted easily moulded parts that presented a paintable, Class A surface with an extremely small gap between car body and part. At the same time, the parts had to be strong enough to meet or exceed impact specifications. On top of all this, the material had to be recyclable to conform to end-of-life requirements. By formulating application-specific Daplen thermoplastic polyolefins (TPOs) to meet BMW’s requirements, Borealis provided the carmaker with a multi-faceted solution for its high-design, high-engineering component needs in time for the Series 1's expected launch later this year.

Daplen EE109AE, a high-impact material, was developed for the BMW bumper. Daplen EE340E, a high-stiffness grade, was developed for the rocker panel. The materials share the Daplen family advantages of design freedom, weight and cost reduction, and ability to withstand minor dings and scratches.

Additionally, the two new grades by design exhibit low thermal expansion and dimensional stability necessary to maintain close tolerances with adjacent body panels. Paint adhesion and surface quality are superb. The materials also maintain excellent impact resistance even at low temperatures while (especially for the bumper) affording protection to pedestrians. Finally, thanks to high-flow characteristics, both grades favour geometrically complex mouldings with short part cycles.

“In the 1970s, automakers began moving away from steel and chrome for exterior elements, looking toward plastics," stated Walter Baumann, Vice President Borealis Engineering Applications. “BMW’s zero-gap materials are the latest in the evolution, where aesthetics and design must be underpinned by strength and long life. Daplen is an ideal solution for this application.”