General Motors and supplier partners Basell, Southern Clay Products and Blackhawk Automotive Plastics have teamed up to produce a nanocomposite TPO-based step-assist for 2002 GMC Safari and Chevrolet Astro vans that assists occupants in stepping into and out of the vehicle.
The innovative material is the result of advanced scientific research at the GM Research & Development Center in Warren, MI and an exclusive GM development agreement with Basell, the world’s largest producer of polypropylene resins for plastics; and Southern Clay Products, which produces the smectite clay additive. The step-assist parts are molded by Blackhawk Automotive Plastics, Inc. of Mason, OH. GM, Basell and Southern Clay have an agreement that grants mutual confidentiality, which is unprecedented in GM’s relationship with outside suppliers.
Southern Clay Products, a subsidiary of Rockwood Specialties Inc., has helped advance nanocomposite technology with its development of an ultrapure smectite clay additive with flakes that are only one nanometer thick (one-millionth of a millimeter). The smectite material is produced in a patented process.
The nanocomposites are made by introducing a solid material into a plastic resin to give it added strength and other desired properties. With the Southern Clay additive, the huge surface areas relative to other additives such as talc, result in exceptional improvements in the properties of the plastics with only a fraction of the inorganic filler. A TPO with as little as 2.5% inorganic nano-clay is as stiff and much lighter than parts with 10 times the amount of conventional talc filler. Nanocomposite parts are stiffer, lighter and less brittle in cold temperatures. They are also more easily recycled.
Rockwood’s Vern Sumner, President of Southern Clay, explains, "The potential market opportunities for our nano-clays involve parts that help GM meet its goal of lighter weight vehicles. It’s important to acknowledge that companies like GM and Basell are driving these applications and that we are working to satisfy new market demands with our technology."