Zeigler natta polymerisation

It is also called as Co-ordination polymerisation. Zeigler (1953) and Natta (1955) discovered that in the presence of a combination of transition metal halides like TCl4, ZnBr3 etc, with an organometallic compound like triethyl-aluminium or trimethyl-aluminium, stereospecific polymerisation can be carried out. Combination of metal halides and organometallic compounds are called Zeigler Natta catalyst.
It is also called as Co-ordination polymerisation. Zeigler (1953) and Natta (1955) discovered that in the presence of a combination of transition metal halides like TCl4, ZnBr3 etc, with an organometallic compound like triethyl-aluminium or trimethyl-aluminium, stereospecific polymerisation can be carried out. Combination of metal halides and organometallic compounds are called Zeigler Natta catalyst.

1. Zeigler Natta Polymerisation BY CH. SAI SRI RAMA CHANDRA MURTHY

2. Ziegler Natta Polymerisation: It is also called as Co-ordination polymerisation. Zeigler (1953) and Natta (1955) discovered that in the presence of a combination of transition metal halides like TCl 4 , ZnBr 3 etc , with an organometallic compound like triethyl -aluminium or trimethyl -aluminium, stereospecific polymerisation can be carried out. Combination of metal halides and organometallic compounds are called Zeigler Natta catalyst .

3. The π –electrons from propylene end up filling Titanium’s empty orbital. Zeigler Natta Catalyst

4. The mechanism involves three steps, Initiation Propagation Termination

5. Initiation: The catalyst from monomer catalyst complexes by reacting with monomer molecule.      

6. X   + n(                     Living polymer Propagation: The monomer catalyst complex reacts with fresh monomers resulting the chain growth as show below.

7.                     Termination: Termination is carried out with an active halogen compound. Dead polymer

8. Application: Used for p roduction of H igh and low density polyethylene. Thermoplastics. Polyolefins . Polybutylene. Crystalline. Polypropylene.

9. Carbon nanotubes. Nanocomposites. Limitations: Poly vinyl chloride cannot be generated. Acrylates.