As known, the existing industrial stereo regular polybutadiene rubber production processes are characterized by appearance of great amounts of waste, conditioned by a stage of washing catalyst oddments from polymer, and formation of smelling oligomers.
We have developed a new generation of high active and efficient bifunctional catalyst- stabilizers for butadiene polymerization with simultaneous stabilization of the end product. Based on Ni- and Co-dithioderivatives in combination with aluminium organics they provide the preparation of:
- low molecular ( liquid ) 1,4-cis- polybutadiene ( cat.: Ni-dithiophosphate or Ni- dithiocarbamate + alkylaluminium haloid ) ;
- high molecular 1,4-cis- polybutadiene ( cat.: Co-dithiophosphate + alkylalumi- nium haloid ) ;
- high molecular 1,4-cis+1,2 - polybutadiene ( 1,4-cis - 64-83%; 1,2 - 15-35%; 1,4-trans - 1-2% ) ( cat.: Co-dithiocarbamate + alkylaluminium haloid ) ;
- high molecular and high crystalline syndiotactic 1,2- polybutadiene ( cat.: Co- xanthogenate + trialkylaluminium ) .
The main feature of these metal complex systems is that to decrease the amount of metal complex components , sharply increase the output of the process amount, to use in the process the butadiene fraction with low content of basic substanse ( fraction C4 ). Besides, such systems are not washed out and remaining in the polymer effectively stabilize it without additional involvement of antioxidants.
Organization of the commercial manufacturing of various types of polybutadienes on the basis of the above mentioned catalyst-stabilizers allows to increase the production capacity of the existing plants ( nearly by 4-5 times ) without extra investments; considerably diminish the amount of waste waters, containing harmful metals, due to elimination of polymer washing from catalyst residues wash out stage from technological cycle; to exclude the use of the expensive antioxidants.
Nickel and Cobalt containing catalytic dithiosystems and processes for produce of various types of polybutadienes were tested starting from laboratory continuous unit to semi-industry plant and are ready for industrial applications.
Development of the technological aspects of different types butadiene rubbers production using the new bifunctional catalyst-stabilizers will allow to organize the ecologically favorable stereoregular polybutadienes preparation processes in Azerbaijan Republic.
Source : Mamedaliyev Institute of Petrochemical Processes of Azerbaijan Academy of Sciences