On the ageing behaviour of NBR: chemomechanical experiments, modelling and simulation of tension set

Rubber components produced from nitrile butadiene rubber (NBR) are changing their material properties due to environmental influences. This is caused by irreversible changes occurring in the elastomer network which is known as chemical ageing. In this paper, ageing behaviour of NBR is investigated and modelled under the influence of different surrounding media as air and oil. Based on the previous works, in which chemical ageing was also modelled, a continuum mechanical approach is introduced here, whereby the rubber viscoelasticity is taken into account. Simulations using FEM are then carried out under different chemical and mechanical boundary conditions, and the proposed modelling approach is validated by means of tension set measurements.