Synthetic Rubber Manual

The Synthetic Rubber Manual, 12th ed.. International Institute of Synthetic Rubber Producers, Inc., 1992. 

TABLE 9.14 ASTM and IISRP Classification of Oils for Oil-Extended Elastomers (The Synthetic Rubber Manual, 1999)... 

Though natural rubber, SBR, and BR represent the largest consumption of elastomers, several additional polymers merit a brief discussion because of their economic significance—nitriles, polychloroprene, butyl, and ethylene-propylene-diene monomer (EPDM) elastomers (Datta, 2004 The Synthetic Rubber Manual, 1999). 

The Synthetic Rubber Manual, 15th Edition 2002 IISRP, Houston, Texas. 

Several other compositions that are commonly classed as crosslinked butyl rubbers are available, although they are not listed as such by their manufacturers, in The Synthetic Rubber Manual—8. They are made by partially curing compounds of unmodified butyl rubber containing additional materials such as fillers, plasticisers and resins they too are used primarily in caulks and sealants. They do not offer the high levels of resistance to sag and flow that are achievable with the terpolymers, but they are much easier to process. 

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