17 March 2015, 00:00
High-tech composites for lightweight construction
The focus of LANXESS’ presence at the VDI conference “Plastics in Automotive Engineering” is on the great opportunities that designs based on the continuous-fiber-reinforced thermoplastic composite Tepex offer for the cost-effective lightweight construction of automobiles. “Using several series applications, we aim to highlight the enormous potential Tepex has to save weight both in the hybrid molding process and in various compression molding processes for fiber-reinforced thermoplastic matrices,” explains Tim Arping, head of Marketing for the EMEA (Europe, Middle East, Africa) region in the High Performance Materials (HPM) business unit. Other focal points the specialty chemicals company LANXESS will be showcasing in Mannheim include a new, highly reinforced but at the same time exceptionally easy-flow Durethan polyamide 6, various Pocan polyesters for external bodywork parts and flame-retardant Durethan polyamides for automotive electrical and electronics circuits.
Significant increase in strength and stiffness
Among other articles, LANXESS will be using the underbody protection from a German compact car to demonstrate the advantages of Tepex as the overlay for locally reinforcing thermoplastic compression molded parts. The component is created in a DLFT (direct long fiber thermoplastic) process from a polypropylene compression molding compound. “The Tepex dynalite 104-RG601 (PP&GF) inserts triple the strength and energy absorption of the DLFT component,” explains Arping. In Mannheim, LANXESS will also be showcasing a material innovation for the DLFT compression molding process in the shape of Durethan B 24 CM H2.0. This polyamide 6 has significantly better flow properties than conventional polyamide 6-based long-fiber molding compounds. It also produces no flue gases on extrusion. Furthermore, its heat resistance means the material can withstand the temperatures involved in cataphoretic painting (CP), thus offering a CP-capable alternative to polypropylenes in the DLFT process. As a sample application, LANXESS will be presenting the demonstration model of a trunk recess for a German sports car.
Examples of the hybrid molding process, where Tepex inserts are simultaneously molded and back-injected in an injection mold include the seat shell for a compact car. “In the event of a crash, the component absorbs considerably more energy than comparable designs using sheet steel or plastics reinforced with long glass fibers. This provides a greater degree of safety,” says Arping. The safety component is approximately 800 grams lighter than previous versions.
Extremely easy flowing despite 60 percent glass fibers
A new material for lightweight design being showcased in Mannheim is Durethan BKV 60 XF. Just like the series-tested Durethan DP BKV 60 H2.0 EF, this polyamide 6 is reinforced with 60 percent glass fibers. However, while its mechanical property profile is of a similarly high standard, its melt flow is more than 30 percent better. “This enables the construction of strong structural components that exhibit intricate rib structures with wall thicknesses of less than one millimeter,” says Arping.
New polyester for fuel caps that can be coated online
Pocan B 5220 XF – a glass-bead-reinforced material specifically designed for fuel caps – is one example of LANXESS’ material innovations for bodywork exteriors. It is dimensionally stable and withstands the temperatures involved in cataphoretic painting. “In this application, we see it as an alternative to polyphenylene ether and polyamide blends and mineral reinforced PBT or polyamide compounds,” explains Arping.
Flame-retardant polyamides with wide processing window
LANXESS will also be showcasing applications for halogen-free flame-retardant Durethan polyamides – including a carrier for high-voltage components in the battery system of an electric vehicle. This is made from injection-molded Durethan BKV 20 FN01. Thanks to its organophosphorus flame retardance package, this extremely tough polyamide 6 achieved the best classification, V-0 (0.75 mm), in tests to the American standard UL 94 (Underwriter Laboratories). Arping: “The special feature of this material is its wide processing window, which enables a reliable and stable injection molding process. Moreover, the material can also be processed at higher temperatures, meaning that longer and more complicated flow paths are also supported.”