Innovative design ideas sprouted like daisies at K 2007, the giant plastics trade show held Oct. 24-31 in Düsseldorf, Germany. There were plenty of interesting collaborative processing innovations, which you expect to see at the K every three years. This K was a little different in the number of new materials offered that included crop-based feedstocks, partly in reaction to rising hydrocarbon costs, but also because of heightened awareness of climate change issues.
Soft Touch Simplified
Four companies joined forces to create a single-step process — combining injection molding and foaming — to produce soft-touch parts used in auto interiors. Called the Dolphin process, it allows the sandwich components used in automotive construction, such as dashboards, center consoles and glove compartments, to be manufactured quickly and cost-effectively. Engel contributed the new injection-molding machine and the Swiss company Georg Kaufmann Formenbau supplied the tool, while the plastic manufacturers BASF and P-Group provided this project with a combination of two polyesters (PBT). A PBT is injection molded and then encapsulated in a chemically related specialty polyester foam.
Bayer MaterialScience has developed polyols based up to 70 percent by weight on renewable raw materials. One exhibit on display was a high-end refrigerator from Liebherr insulated in polyurethane rigid foam that attained the German high energy efficiency classification A+. The proportion of renewable raw materials is double that of conventional polyurethane insulating foam systems. The processing and final properties of the new foam system are identical to those of the rigid foams already available on the market for this application and in some respects surpass them. Consequently, this kind of refrigerator not only lowers energy consumption but — as a result of the materials selected — also helps protect the climate.
Conductive plastic dissipates electrostatic charge
Siemens VDO has adopted Hostaform acetal copolymer from Ticona, the engineering polymers business of Celanese Corp., to dissipate electrostatic charge in the fuel supply unit of the Ford Transit. The compound is an extended-use, conductive grade developed for auto fuel systems, especially those that handle aggressive fuel blends at elevated temperature.
The Siemens' application involves an acetal holder for the contact system of a fuel level indicator and the lever arm/float assembly mounted to it. This system must operate over the life of the car in various fuels at service temperatures from -40 to 80C, which reflects the increased thermal requirements of diesel engines. Plastic fuel system components can become electrostatically charged as flowing fuel causes charge separation. The likelihood of charge build-up occurring, and thus sparking, rises as fuel systems operate at higher pressures and flow rates. Ticona's new electrostatically dissipative POM was developed to avert such charge accumulation.