METHOD FOR PRODUCTION OF SYNDIOTACTIC (CO)POLYMER OF PROPYLENE Russian patent published in 1997 - IPC

FIELD: production of plastics. SUBSTANCE: polymerization of propylene or its copolymerization with other unsaturated hydrocarbons is carried out at (-60)-200 C and at pressure 0.5-100 bar. The process takes place in the presence of two zirconocenes and linear or cyclic alumoxanes or their mixture with compound having formula $$$ where R is H, $$$-alkyl, $$$-fluoroalkyl, $$$-aryl, $$$-fluoroaryl. At least two compounds having common formula $$$ where $$$ and $$$ are the same or different $$$-alkyl, $$$-alkoxy, $$$-aryl, $$$-aryloxy, $$$-alkenyl, halogen or H; $$$ and $$$ are different single- or polycyclic hydrocarbon residues which form together with central zirconium atom sandwich-like structure, $$$ where $$$ and $$$ are the same or different halogen, hydrogen, $$$-alkyl, $$$-fluoroalkyl, $$$-fluoroalkyl, $$$-aryl, $$$-alkoxy, $$$-alkenyl are used as mentioned above zirconocenes. EFFECT: improved efficiency.