Recent Developments in Synthetic Rubbers by Anionic Polymerization

RECENT DEVELOPMENTS IN SYNTHETIC RUBBERS BY ANIONIC POLYMERIZATION 

Hargis, R. A. Livigni and S. L. Aggarwal GenCorp, Research Division, Akron, Ohio, USA 

The objective of this chapter is to provide a survey of the technological developments in solution rubbers prepared by homogeneous anionic polymerization. Emphasis will be on butadiene and styrene monomers, and catalyst systems based on organolithiums and their complexes with Lewis bases plus some unpubhshed work on alkahne earths from the authors laboratory. The rubbers thus obtained offer means for control of molecular structural features of polybutadiene and poly(butadiene-co-styrene) that directly relate to the functional properties of tyre rubbers. 

Early work bearing on organolithium-initiated diene polymerization was reported by Ziegler and co-workers in 1934. It was demonstrated that the organolithium adds to the diene double bond to give an intermediate capable of reacting further with the diene. 

The characteristics of the organolithium-initiated polymerization of the dienes was clearly established by Morton and co-workers. It was demonstrated that the polymerizations are of the living type, which take place without a chain termination reaction in the absence of impurities.The implications of this behaviour in preparing polymers of controlled structure are well recognized today. 

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Hargis G, Livigni RA, Aggarwal SL. Recent development in synthetic rubbers by anionic polymerization. In Whelan A, Lee KS, editors. Developments in Rubber Technology—4. Essex, UK Elsevier 1987. p 1. 

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