The new-generation Hydrocerol, developed by the Clariant Masterbatches business unit, creates a finer, more durable foam-cell structure that allows manufacturers to achieve surface quality and mass reduction of between 5 and 20% (depending on part design and application). The results have been demonstrated in components molded from polymers such as thermoplastic olefin (TPO) elastomer, polypropylene (PP), and polyamide (PA), even parts made from up to 30% glass- and mineral-filled materials. Applications under development include door panels, ceiling panels and head liners, and instrument-panel sections (IP Lower).
"Mass reduction has become one of the most important objectives in the global automotive industry," says Rick Spring, Automotive Segment Head, Clariant Masterbatches, North America. "The newest fuel-economy mandates issued in the U.S. and Europe demand it and, although plastics account for a relatively small percentage of overall vehicle weight, every bit can help reduce demand for fossil fuels and cut greenhouse-gas emissions. Clariant is committed to supporting environmental initiatives like this."
The improved CFA technology used in the new Hydrocerol masterbatches makes it possible to achieve a highly consistent structure of cells as small as 60 microns in diameter. This compares very favorably to the 400 microns typical of first-generation foams and even the 180 microns, which was considered "fine" just a few years ago. As a result, there is virtually no appearance or performance difference between structures produced with CFA versus those made without it.
Paintability can be maintained in most materials up to 7% material reduction. A reduction in material use also leads to cost reductions. Adding just 1% Hydrocerol CFA can reduce net material costs by 5% or more. However, the savings that result from improved processing characteristics are reportedly even more impressive.
The new Hydrocerol masterbatches that have been developed for automotive applications are endothermic foaming agents. The chemical reaction that creates the foam absorbs heat so that less heat needs to be removed from the polymer after molding and processing cycles are shorter. Shorter cycle times mean machine and labor productivity can be increased by as much as 20%.
At the same time, the new Clariant CFAs incorporate proprietary scavenging technology that neutralizes the effects of moisture, CO2 and acids that are the natural byproducts of chemical foaming. Uncontrolled, these byproducts can cause corrosion in injection molds and also create surface defects in molded parts.
"The Clariant scavenging technology absorbs moisture and acid during foaming," explains Kirk Jacobs, Director, Product Line Additives. "It means the CFA is not as finicky to implement in a production environment. Corrosion becomes a non-issue and, in combination with the finer cell structure, the elimination of moisture allows processors to achieve the clean, high-quality surface their automotive customers are looking for."
Hydrocerol technology is standardized globally, with production in North America, Europe and Asia.