Vegetable oils distinguishing from animal fats

The combination of properties that distinguishes butyl rubbers from highly unsaturated elastomers such as NR, SBR and NBR includes exceptionally low permeability to gases and vapours outstanding ability to absorb mechanical energy and excellent stability when exposed to ozone, wet and dry heat, all climatic conditions, aqueous corrosive chemicals, and animal and vegetable fats and oils. 

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