Polymerization of Propylene using TiCl4 Catalyst

Experiments were carried out to polymerize propylene in a slurry using a catalyst of TiCl₄, DBP (dibutylphthalate), and MgCl₂. The process was carried out in a 1 L stainless steel reactor with a stirrer that rotates at 360 revolutions per minute. The polymerization medium that was used was heptane, and 500 mL of heptane was introduced into the reactor. The propylene was saturated at a pressure of 0.3 mega Pascals (MPa) to initiate polymerization for 30 min. Then, specific amounts of an aluminum alkyl activator and CMDMS (an external donor) were added to the reactor, maintaining an Al/Si molar ratio of 4.7. Next, a specified amount of the catalyst was injected into the reactor to start the polymerization reaction at the desired temperature. CO₂, CO, and O₂ were added to the propylene supply line (look at Table 1).
After the polymerization was complete, acetone was added to stop the process, and then the suspension was transferred to a receiving flask that was kept under a nitrogen (N₂) atmosphere. The synthesized powder was washed three times with 200 mL of heptane and then dried in a vacuum at room temperature. The resulting polymer was stored under dark, nitrogen, and temperature-controlled conditions. It is essential to highlight that all the procedure steps were carried out very carefully in a nitrogen atmosphere to avoid air.
The standard polymerization conditions were as follows: polymerization temperature = 70 °C, amount of catalyst = 5 Kh/h, type of activator = TEAL, concentration of activator = 0.25 Kh/h, 30 g/h of H₂, and 1.2 TM/h of propylene at a pressure of 27 bar.