Stereo rubbers

The first synthetic rubbers to be commercially available in United States were Thiokol (1930) and Neoprene (1931). Both of these are still being produced commercially because they have special properties that are not matched by natural rubber. Various types of synthetic rubbers were introduced during (1939-43) World War II. After world war, stereo rubbers have been made using stereo specific catalysts. 

The Stereo Rubbers, W. M. Salt man, ed., Wiley-Interscience, New York, 1977. 

The coordination catalysts were quickly extended to dienes and found to produce the long-sought objective of a "synthetic natural rubber, i.e., cis-1,4-polyisoprene. cis-1,4-Polybutadiene was also quickly produced. These were, and still are, erroneously referred to as stereo rubbers. They are actually unique geometric isomers rather than stereoisomers, but the name stereo rubber became established probably because of the relationship in time and catalyst usage to stereo olefin polymerization. 

Saltman WM (ed) (1977) The stereo rubbers. John Wiley, New York... 

Duck EW, Locke JM. Polydienes by anionic cataiysts. In Saltman WM, editor. The Stereo Rubbers. New York Wiley Interscience 1977. p 139. 

R. M. Murray and D. C. Thompson, The Neqprenes, Elastomer Chemicals Department, E. L Du Pont de Nemours, Wilmington, DeL, 1964 W. M. Saltman (ed.). The Stereo Rubbers, Wiley, New York, 1977... 

Whilst for various reasons these rubbers, often referred to as stereo rubbers because of the stereospecific action of the catalysts during polymerization, and which include not only polyisoprenes and polybutadienes but also ethylene-propylene rubbers, have not yet seriously challenged the predominance of SBR and natural rubber, they have become important and successful materials. 

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