Study of relations between viscoelasticity and tribological behaviour of filled elastomer for lip seal application

Improvement of ball-bearing performance requires an optimization of desired properties of rubbery lip seals. Such an application necessitates specific material properties such as thermomechanical and tribological behaviours. These requirements led to investigate relationship between viscoelastic properties and tribological behaviour of filled elastomers. To achieve this objective, an analysis of two nitrile rubbers (NBR), which mainly differed in their glass transition temperature (Tg) values, was performed. This difference was obtained by a modification of the matrix composition. This work is focused on the difference of their tribological behaviour in relation to their viscoelastic, thermomechanic and physicochemical characteristics. It is pointed out that the sample with higher Tg shows the formation of an oxidised protective layer on the surface, which prevents its wear. The lower Tg sample, which shows high wear, does not have such a protective layer.