Coordination Polymerisation in Polymer Chemistry and

The use of coordination catalysts, especially homogeneous vanadium-based catalysts, for the copolymerisation of ethylene and propylene, with an ethylene content of 15-75 mol.-% in the feed, made it possible to produce amorphous 

In 1954, 1,4-cA-polyisoprene, the synthetic equivalent of natural rubber, was obtained in the laboratories of Goodrich-Gulf [22] by isoprene polymerisation with new catalysts developed by Natta, and later on 1,4-trans-polyisoprene, a synthetic analogue of gutta percha, was obtained by Natta et al. [23]. 

At the same time, syndiotactic polypropylene was also isolated by Natta et al. and characterised [145]. Syndiotactic polypropylene which was obtained by low-temperature polymerisation using soluble vanadium-based catalysts [146] could not be, however, commercialised, although it had a blend of interesting usable properties. 

It may be of interest that isotactic polystyrene formed by styrene polymerisation with Ziegler Natta catalysts [13] did not appear to be a polymer that could exhibit significantly better usable properties compared with atactic polystyrene produced in free radical styrene polymerisation processes. 

The Ziegler-Natta catalysts have acquired practical importance particularly as heterogeneous systems, mostly owing to the commercial production of linear high- and low-density polyethylenes and isotactic polypropylene. Elastomers based on ethylene-propylene copolymers (with the use of vanadium-based catalysts) as well as 1,4-cz s-and 1,4-tran.y-poly(l, 3-butadiene) and polyisoprene are also produced. These catalysts are extremely versatile and can be used in many other polymerisations of various hydrocarbon monomers, leading very often to polymers of different stereoregularity. In 1963, both Ziegler and Natta were awarded the Nobel Prize in chemistry. 

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