METHOD OF PRODUCING BRANCHED POLYPROPYLENE Russian patent published in 2011 - IPC C08F10/06 C08F4/64 C08F2/06 

FIELD: chemistry.

SUBSTANCE: described is a method of producing branched polypropylene, having branching index g' less than 1.00. The method includes a step for polymerisation of propylene and, optionally, another (other) comonomer(s) in non-critical conditions in a reaction vessel. Pressure in the polymerisation process is at least 45.4 bars (4540 kPa). Temperature in the polymerisation process is lower than 90°C. Polymerisation takes place in the presence of a catalyst system, having surface area not greater than 350 m²/g measured in accordance with ISO 9277. Said catalyst system contains a metallocene catalyst, having zirconium as a transition metal and two cyclopentadienyl rings of different chemical structure. Described also is a method of polymerisation in the presence of the catalyst system having pore volume less than 3.50 cm³/g measured in accordance with DIN 66135 (N₂).

EFFECT: method of producing branched polypropylene in mild conditions and obtaining reproducible results.

20 cl, 5 dwg, 4 tbl, 3 ex