The injection-molded thinwall instrument panel retainer in the 2014 Chrysler Jeep Cherokee is reportedly the industry's first to attain 2.0 mm in thickness. It employs a long glass fiber-reinforced polypropylene (LGFPP) material supplied by Sabic Innovative Plastics (Pittsfield, MA). The Stamax 30YK270 grade has a 30% glass fiber loading).
The part is 1.68 lb. lighter (27%) that the previous version, molded from talc-filled PP but with thickness that typically varied between 2.5 mm and 4.0 mm depending on the design. The initial design of the new Jeep Cherokee instrument panel (IP) specified a conventional thermoplastic olefin (TPO) material that would have achieved a thickness of 3.0 mm. The high-flow properties of Stamax resin allowed for thinner-walled 2.0-mm parts that are structurally strong, but also light.
Thinwalling also enables a cycle time reduction of approximately 30% versus the conventional 3.0-mm-thick part due to faster cooling time. A cost saving of $3 per vehicle is also realized.