HT-ACM & XT-ACM Heat and Fluid Resistant Acrylic Rubber
Abstract
In the early 21st century, we introduced a new high temperature Noxtite® ACM type family (HT-ACM’s) with significantly improved heat resistance compared to existing acrylate polymer grades. Those developments opened the scope of applications to longer lifetimes i.e. in Noxtite® ACM head cover gaskets or other sealings e.g. O-rings or precision molded parts and also in new fields of applications for turbo charger, fuel and oil hose applications.
The continuing trend for super charged engines, as a tribute to better fuel economy, along with smaller engine compartments and encapsulation of the engine block added new requirements to elastomeric parts under the hood up to 190°C where 150°C had been sufficient before or, otherwise, high cost FKM and VMQ needed to be used. Unimatec´s technology closed this new temperature gap between ACM and FKM with the newly developed Noxtite® HT-ACM types. This generation of Noxtite® HT-ACM became superior in heat-resistance up to 190°C.
This paper highlights further Noxtite® HT-ACM grade developments in regard to significantly improving agressive fluid resistance e.g. in fuels and new highly additivated engine and transmission fluids used in “blow-by”, EGR as well as engine and transmission oil hose type applications respectively. A study including heat ageing, engine and automatic transmission oil as well as fuel immersion data will also show the strengths of Noxtite® based formulations in comparison with other polyacrylate rubber compositions.