Direct bonding of plastic and rubber for manufacturing automotive cooling circuits


Release Time :

2022-05-12

"This can be ensured by the high chemical resistance of PPA and the properties of VESTAMID® HTplus R1033 in terms of adhesion." says Frank Lorenz, Head of Applications for Automotive Products at Evonik. The plastic parts remain dimensionally stable even during the elastomer vulcanization process, which allows the components to be used without any failures after a million cycles.

VESTAMID® HTplus R1033, a special polyethylene terephthalamide (PPA) from Evonik Industries, and the newly developed hydrogenated nitrile butadiene rubber (HNBR) elastomer from KACO GmbH & Co. The parts are based on a patented plastic-rubber direct bonding technology and have been installed by leading automotive manufacturers. This technology allows the plastic and rubber parts of the component to be firmly bonded without any pre-treatment. In addition, no adhesive is required in the production process. To achieve this, such materials as VESTAMID® HTplus R1033 must be specially modified. The newly developed HNBR elastomers from KACO show excellent initial adhesion. Regarding the use of VESTAMID® HTplus R1033, Marcus Teller, product developer for the company's seals, says: "We decided to support this production process because direct bonding technology avoids the dimensional differences in components that are associated with the use of adhesives. Considering the low tolerance range we needed to achieve, this dimensional variation was unacceptable." In turn, this means that plastic parts cannot change their dimensions in different cooling media (the glycol-water mixtures used by different car manufacturers). The bonding of the part to the HNBR must remain stable in all media or extreme temperature conditions. "This can be ensured by the high chemical resistance of PPA and the properties of VESTAMID® HTplus R1033 in terms of adhesion." says Frank Lorenz, head of automotive applications at Evonik. The plastic parts remain dimensionally stable even during the elastomer vulcanization process, which allows the components to be used without any failures after a million cycles.