Cooling circuit parts installed by automotive manufacturers consist of a direct composite comprising the special polyphthalamide (PPA) VESTAMID HTplus R1033 by the Resource Efficiency segment of Evonik, and a newly developed HNBR elastomer by KACO GmbH & Co. KG. The composite is generated with the patented plastic-rubber technology, which enables the firm bond of a component's plastic and rubber parts without pretreatment. The process does not require the application of an adhesion promoter. The plastic material, such as VESTAMID HTplus R1033, must be specifically formulated for this purpose. The newly developed HNBR elastomer by KACO shows enhanced initial adhesion. The bond with HNBR also must remain stable when the part is in contact with various media or subjected to temperature extremes, which is ensured by the high chemical resistance of PPA as well as the special properties of VESTAMID HTplus R1033 for composite bonding. The plastic part remains dimensionally stable even in the elastomer vulcanization process, which allows for trouble-free component function for a million transmission cycles depending on the transverse path. For more information, visit www.evonik.com.