Press release
November 19, 2015

Polyphthalamide VESTAMID® HTplus and HNBR component for automotive cooling circuit manufactured with plastic-rubber technology

Cooling circuit parts installed by renowned automotive manufacturers consist of a direct composite comprising the special polyphthalamide (PPA) VESTAMID® HTplus R1033 by Resource Efficiency Segment of Evonik, Essen, and a newly developed HNBR elastomer by KACO GmbH & Co. KG, Heilbronn. The composite is generated with the patented plastic-rubber technology.

This technology enables the firm bond of a component's plastic and rubber parts without pretreatment. Moreover, 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 outstanding initial adhesion. "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, about the use of VESTAMID® HTplus R1033.

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 for composite bonding," says Frank Lorenz, who is responsible for automotive product applications at Evonik. 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.

Company information

Evonik, the creative industrial group from Germany, is one of the world leaders
in specialty chemicals. Profitable growth and a sustained increase in the value of the company form the heart of Evonik’s corporate strategy. Its activities focus on the key megatrends health, nutrition, resource efficiency and globalization. Evonik benefits specifically from its innovative prowess and integrated technology platforms. Evonik is active in over 100 countries around the world. In fiscal 2014 more than 33,000 employees generated sales of around €12.9 billion and an operating profit (adjusted EBITDA) of about €1.9 billion.

Evonik Industries has been producing specialty chemical products in the Greater China region (Mainland China, Hong Kong and Taiwan) since the late 1970’s; with wide-ranging trading relations already in place prior to this in the region. Evonik regards Greater China as one of the driving forces of the global economy and we consequently endeavour to grow our business in the region. The company now has around 3,000 employees in the Greater China region, the regional sales reached over €1.1 billion in 2014.


In so far as forecasts or expectations are expressed in this press release or where our statements concern the future, these forecasts, expectations or statements may involve known or unknown risks and uncertainties. Actual results or developments may vary, depending on changes in the operating environment. Neither Evonik Industries AG nor its group companies assume an obligation to update the forecasts, expectations or statements contained in this release.