Testing and Characterization of Vulcanized Nitrile Swelling Elastomers

This paper describes preliminary methodology and characterization of the vulcanized nitrile butadiene rubber (NBR) samples submitted to swelling and mechanical testing. Nitrile rubber was used to study swelling processes of swelling packer sealing element. Five different compositions for a rubber vulcanization were used trying to build the best possible combination of components applying different concentrations of each component. Both swelling and mechanical testing were done at the room temperature. Rubber samples swelling was performed in oil acquired from one of Croatian oil fields. The other part of the testing sequence refers to tensile stress-strain tests to the point of break performed on dumbbell samples. Tensile testing was rendered on non-swollen rubber samples using a tensile testing apparatus. From the obtained results it can be seen that swelling process of the nitrile rubber strongly depends on cross-link density.