BS 6996:2003

Foreword
1 Scope
2 Normative references
3 Classification
4 Composition
5 Preparation of test sheet
6 Physical properties of the vulcanized test sheet
7 Marking
Annex A (informative) Guidance for the preparation
        and testing of products
Bibliography

Gives compositional and physical property requirements for six acrylonitrile-butadiene rubber compounds resistant to mineral oil and of hardness range 40 IRHD to 90 IRHD.

This British Standard specifies compositional and physical property requirements for six acrylonitrile-butadiene rubber compounds resistant to mineral oil and of hardness range 40 IRHD to 90 IRHD.

These compounds are intended for the manufacture of items in the form of extrusions, mouldings and sheet, and for items cut or punched from sheet, in which resistance to mineral oils without excessive shrinkage is a necessary property, and where some stiffening of the harder grades at temperatures below –20 °C can be tolerated.

NOTE Ozone, which is naturally present in the atmosphere, can cause unprotected nitrile rubber to crack when it is strained, and this can often lead to failure of the part.

The nitrile rubber compounds specified in this standard are not required to be compounded to be resistant to ozone attack and their resistance to ozone is not tested.

Potential users should seek technical advice if they are unsure as to whether ozone resistance is required for their application. There is currently no British Standard for ozone resistant nitrile rubber compounds.