加料方式对钒系催化剂MAV-01聚合性能的影响

The Effect of Feeding Method Catalyst on the Polymerization Performance of Vanadium-based Catalyst MAV-01

制备了钒系聚乙烯催化剂MAV-01,以三异丁基铝(TIBA)为助催化剂,研究了淤浆聚合体系中催化剂加料方式对其聚合性能的影响。优选了较佳的加料方式为:先将助催化剂加入氮气保护的反应系统中,加入定量氢气,然后加入乙烯到接近反应压力0.9MPa,将钒系催化剂加入聚合体系,之后补充乙烯至反应压力1.0MPa。在此条件下,钒系催化剂MAV-01的聚合活性较高,制备的聚合物具有较高的熔体流动速率和较宽的相对分子质量分布。

A novel vanadium-based polyethylene catalyst MAV-01 was synthesized. The effects of feeding method of catalyst on the polymeriza- tion performance were studied with using triisobutylaluminium （TIBA） as a cocatalyst in slurry polymerization process. The optimal feeding method was found as follows. The TIBA was introduced into the reactor under nitrogen atmosphere, followed by adding certain amount of hydrogen. Then the ethylene was fed into the reactor until the reaction pressure was close to 0.9MPa. After adding vanadium-based catalyst MAV-O1, the polymerization was initiated by adding ethylene to make the reaction pressure be 1.0MPa. Under these conditions, the polymerization activity of MAV-01 catalyst was higher, and the polymer with higher melt flow rate and wide molecular weight distribution was obtained.