Stereo and Speciality Rubbers

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. 

The materials described so far in this brief review were designed largely to fit into existing rubber technology. During the past 20 years there have been two developments which have led to a radical new approach. The first is the technology of using liquid rubbers and the other the development of the thermoelastomers. 

Liquid rubber technology has largely stemmed from the development of the polyurethanes. These materials were first produced in the 1930s in fibre form in an attempt to circumvent the Du Pont patents on the nylons. During World War II this led on to the solid Vulkollan rubbers and subsequently to the rigid and flexible foams. Modern processes can be adapted for such disparate products as car tyres, car body parts and soft, printers rollers. Such technology owes little to the traditional methods of the rubber industry. 

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