Effects of Green Silica on Nitrile Butadiene Rubber Composite on Its Enhanced Mechanical Characteristics

ABSTRACT The silica‐filled nitrile butadiene rubber (NBR) composites are oil resistant, and they are frequently employed in oil seals. Both the composite compositions and the curing environment have a significant impact on the properties of oil seals. Silica loading (10–50 phr) is recognized to have a significant impact on composites mechanical properties. The silane coupling agent treatment on silica is to enhance compatibility with the NBR matrix; the composites were made in a two‐roll mill. In addition to their mechanical characteristics, the effect of silica loading on NBR composites cure and scorch times was studied. The mechanical characteristics, such as hardness, tensile strength, elongation at break, oil resistance property, rubber‐to‐filler interactions, and cross‐link studies have been discussed. The results showed that increasing the amount of green silica from 10 to 50 phr in the composite improved its strength and durability. The Si189‐GS fillers were uniformly distributed and compatible in the NBR matrix at low loading (10 and 30 phr), but agglomeration became apparent at 40 phr. In view of the strong silica‐NBR matrix contact that limits rubber chain segmental motion, silica‐filled NBR composites have higher silica loading, and the composites are tougher and harder.