Ester plasticizers for high-temp AEM elastomers

摘要

Ethylene acrylic elastomers traditionally have been used in applications requiring high level of performance under extreme temperature conditions. They are typically used in a wide variety of automotive applications, such as turbo chargers, oil cooler hoses, seals and gaskets. Recent advancements in ethylene acrylic elastomers by DuPont have pushed this performance to higher temperatures and longer periods of time through their Vamac-brand VMX 5000 series of polymers. Low temperature improvements, however, are traditionally achieved through the addition of high performance ester plasticizers. While many of these plasticizers have been used in Vamac compounds to great effect in the past, the need for performance at higher temperatures necessitates the development of new materials to improve on permanence and volatility. This paper provides information on newly developed plasticizers intended to improve high temperature resistance without sacrificing low temperature performance. Test data include heat aging for varying durations at high temperatures as well as comparative changes in physical and low temperature properties before and after aging. The information provided indicates that the permanence of the plasticizer is key to maintaining compound performance after extended exposure to high temperatures.