Synthesis of Stereoregular Polydienes

Ziegler-Natta stereoregular polymerisation of a-olefins and dienes was discovered in 1954. This reaction opened opportunities for the synthesis of various stereoregular olefins and dienes. It occurs in the presence of catalytic systems, formed by organic 

Various metal complex systems of Ziegler type are widely applied within industry for the production of high-density polyethylene, isotactic polypropylene, 1,4-c/s-and 1,4- rans-polymers of isoprene and 1,2-poly butadiene, and many other types of copolymers, such as ones based on ethylene and propylene, which could not be produced earlier based on traditional methods of synthesis. 

Despite tremendous success in the development of scientific fundamentals for stereospecific polymerisation and the commercial production of stereoregular polymers, three key theoretical problems are still under discussion a) the structure of AC b) the mechanism of initiation and chain growth processes and c) the reasons and factors responsible for the stereoregular products of a-olefins and 1,3- diene polymerisation in the presence of Ziegler-Natta catalysts. 

Stereospecific polymerisation of isoprene (2-methyl-butadiene-1,3) in the presence of cis-regulating catalytic Ziegler-Natta systems can be described by the following 

tubular turbulent diffuser-confusor prereactors provide a uniform distribution of catalyst particles in a reactor volume during the fast stages of macromolecule growth centre formation and the initiation reaction for the copolymerisation of olefins and dienes on microheterogeneous Ziegler-Natta catalysts. Equal conditions are provided in this case for the motion of all potential AC in a diffuser-confusor prereactor. 

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