Pocan C 1202, a blend of polybutylene terephthalate and polycarbonate (PBT+PC) newly developed by LANXESS for large exterior truck components, has proven highly effective in an initial series application. It is used to manufacture the uncoated radiator grille for the FMX Construction Truck in the FM series. This was fitted with a completely new front section by Volvo Trucks Corporation that is specially adapted to the harsh operating conditions in construction site traffic, for instance. “Our material had the edge because it gives components a high-quality, sufficiently weather-resistant surface that has a fine grain pattern and no longer needs to be coated. It also demonstrates a high toughness level that makes the radiator grille resistant to stone chippings and other mechanical stresses,” explained Jürgen Horstmann, Key Account Manager for the truck industry in the Semi-Crystalline Products business unit. The radiator grille is produced by Gerhardi Kunststofftechnik GmbH in Lüdenscheid, Germany, a leading manufacturer of plastic components for vehicle interiors and exteriors in Europe.
With dimensions of around 180 x 35 x 4 centimeters, the radiator grille is very large for an injection-molded part. For that reason the relevant mold is filled using cascade technology. “This is where the excellent flowability of our non-reinforced material pays off, despite its high toughness level,” said Horstmann. Latching lugs and mounting domes can also be reproduced reliably at the end of the flow path, for example. In addition, the excellent flow behavior causes only minimal distortion and ensures the fine grain pattern can be reproduced with great precision. The ease of removal from the mold and the low and consistent shrinkage complement the material’s outstanding processing behavior.
In order to cut costs, the radiator grille is not coated. Accelerated, artificial weathering tests on test pieces with Thundergrey paint, for example, showed that the PBT blend meets the requirements for UV stability based on the Volvo standard. Good chemical resistance was also called for. “Our material shows excellent resistance to media that vehicles encounter on an everyday basis, such as road salt, grease, oil, diesel, liquid coolant, AdBlue urea solutions, battery acid, and insect and windshield cleaners,” explained Dr. Ulrich Plutowski, product developer for Pocan.
LANXESS has now developed a wide range of PBT blends for truck paneling and moldings such as fenders, wind deflectors, A pillars, bumpers and access steps. “Our materials meet specific needs in each case, enabling us to offer very stiff, low-distortion or easily coatable blend varieties,” explained Horstmann. Numerous projects on large external components in the driver’s cab are currently under way using these PBT grades in conjunction with truck manufacturers and system suppliers.
LANXESS is a leading specialty chemicals company with sales of EUR 7.1 billion in 2010 and currently around 14,850 employees in 24 countries. The company is represented at 45 production sites worldwide. The core business of LANXESS is the development, manufacturing and marketing of plastics, rubber, intermediates and specialty chemicals.