- Polyphthalamide (PPA) and HNBR elastomer component for automotive cooling circuit
- Dimensional stability when exposed to various cooling media and temperatures
- PPA specifically formulated for this application
A patented plastic-rubber technology enables the firm bond of a component’s plastic and rubber parts without pretreatment. In addition, the process does not require the application of an adhesion promoter. Examples are cooling circuit parts installed by renowned automotive manufacturers consisting of a special polyphthalamide (PPA) and a newly developed HNBR elastomer.
Polyphthalamide (PPA) specifically formulated for this application
“We decided in favor of this production process because the direct composites prevent undefined modifications in the component’s interior, which may result from applying a bonding agent. Given the low tolerance ranges we work with, that would be unacceptable,” says Marcus Teller, product developer of sealant parts at KACO.
The polyphthalamide (PPA) Vestamid HTplus R1033 of Evonik is specifically formulated for this purpose. The newly developed HNBR elastomer by KACO GmbH & Co. KG shows very good initial adhesion.
Dimensional stability when exposed to various cooling media and temperatures
Conversely, this implies that the plastic part cannot change its dimensions when exposed to various cooling media – the glycol-water mixtures used by different automotive manufacturers. The bond with HNBR also must remain stable when the part is in contact with various media or subjected to temperature extremes. This is ensured by the high chemical resistance of PPA as well as the special properties of Vestamid HTplus R1033. 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 transvers path.