DSM Engineering Plastics has announced a new addition to its Arnitel line of copolyester thermoplastic elastomers (TPEs) that is designed to meet the stringent performance and compliance needs of today’s automotive designers.

“Arnitel C, a breakthrough technology for wire and cable coating, delivers the best high-heat aging performance of any TPE-E, combined with halogen-free flame retardance and hydrolysis resistance that surpasses that of other copolyester elastomers,” DSM said.
“Thanks to its excellent abrasion resistance, this new material offers designers the ability to reduce the weight and mass of wiring and cable through ultra-thin-wall coatings. In addition to automotive engine cables, Arnitel C is ideal for other extrusion applications including cable harness components, convoluted tubes and hoses,” it said.
“As auto designers try to fit more and more components into a fixed space, it becomes critical to improve wire and cable coating flexibility and reduce mass and weight,” said Francis Aussems, DSM innovation programme manager. “Additional under-the-hood content is also leading to rising temperatures that require improved heat resistance. We developed Arnitel C specifically to meet these needs. In addition to exceptional performance, our new recyclable, halogen- and plasticiser-free TPE helps OEMs and Tiers meet environmental regulations.”
DSM said Arnitel C TPE offered a number of advantages over traditional materials.
“Ethylene tetrafluorethylene (ETFE) is significantly more expensive – at a higher density – than Arnitel C and is not halogen-free. Compared to the DSM material, cross-linked polyethylenes (XPEs) resins for this temperature segment are not available in halogen-free formulations; in addition, they require post-processing E-beam treatment. Arnitel needs no plasticiser to enhance flexibility, which translates into low outgassing and no environmental issues. The combination of this polymer with the halogen-free flame retardant system also gives low toxicity and smoke in case of a fire.”
It said the new material provided the best high-heat aging properties of all TPE-Es, with a continuous operating temperature rating of 3,000 hrs at 175° C; therefore, it exceeded the requirements for temperature class D under ISO 6722. Arnitel C also was hydrolysis-resistant (>150 days at 85° C in water), and on a par with all other higher standard copolyester elastomers. In addition to its unique combination of heat and hydrolysis resistance, Arnitel provided excellent abrasion resistance (five times more cycles than ETFE or XPE in the needle test), excellent flexural fatigue resistance, and good resistance to automotive fluids and other chemicals. The material had been tested and approved according to ISO6722 and LV112.
Kromberg und Schubert GmbH, a German manufacturer of cables and wires for automotive and industrial applications, selected Arnitel C for under-hood, temperature class D coating applications. The company’s single-wire and multi-core cables benefit from the excellent abrasion, wear and chemical resistance of the product.
Heinz Paul from Kromberg und Schubert commented: “Due to a unique combination of heat stability and excellent abrasion resistance, Arnitel C affords for the first time an opportunity to design automotive wires with ultra-thin-wall insulation for under-the-hood applications. This can contribute to weight and volume reduction in automotive wiring.”
Cables coated with Arnitel C can be easily overmoulded with, for example, polybutylene terephthalate (PBT), which is a common material for connectors. Unlike ETFE and XPE, Arnitel provides waterproof adhesion to the connector.