Question

The chemical formula of Ziegler- Natta catalyst is:
(A) $CuC{l_2}$
(B) $NiC{l_2}$
(C) $CrC{l_3}$
(D) $TiC{l_4}$

Answer 1

Ziegler-Natta catalyst is a catalyst used in the synthesis of polymers of $1 -$ alkenes (alpha olefins). A Ziegler-Natta catalyst, named after Karl Ziegler and Giulio Natta, is a catalyst used in the synthesis of polymers of 1-alkenes (alpha-olefins).

Complete step by step answer:
Ziegler-Natta catalyst is a mixture of triethyl aluminium and titanium tetrachloride i.e. $Al{\left( {{C_2}{H_5}} \right)_3} + TiC{l_4}$. It is used for polymerization of alkenes to produce polymers.
Ziegler-Natta catalysts are typically based on titanium compounds, for example ${\left( {{C_2}{H_5}} \right)_3}Al$.
This catalyst are used to polymerize terminal $- 1 -$ alkenes
$nC{H_2} \to {\left[ {C{H_2} - CHR} \right]_n}$

Additional Information:
Discovery and Stereochemistry:
Karl Zeiglar prepared linear polyethylene with the catalyst he discovered.
Giulio Natta used a similar catalyst to polymerize$- 1 -$ alkenes. Poly ($1 -$ alkene) can be isostatic, syndiotactic or atactic, depending upon the relative orientation of the alkyl groups in polymer chains consisting of groups $\left[ {C{H_2} - CHR} \right]$. In isostatic polymers, all chiral centres $CHR$ share the same stereochemistry. Chiral centres in syndiotactic polymers alternate their relative stereochemistry. The stereo regularity of the polymer depends upon the type of catalyst used to prepare it and once prepared the polymer’s stereochemistry doesn’t change.

Note: The Ziegler-Natta catalyst represents a major breakthrough in polymerization chemistry because they produce a variety of commercially important polymers and can be highly stereo selective.