DQ预聚合催化剂的研究

用DQ催化剂制备了DQ预聚合催化剂,考察了不同条件制备的DQ预聚合催化剂对丙烯聚合活性、聚合动力学行为及聚丙烯性能的影响。实验结果表明,DQ预聚合催化剂可以改善聚丙烯的颗粒形态,并使聚合动力学曲线更加平稳,DQ催化剂-DQ预聚合催化剂-聚丙烯之间存在良好的复形关系;采用10℃下制备的DQ预聚合催化剂进行丙烯淤浆聚合时得到的聚丙烯颗粒形态最好,采用在20℃下制备的DQ预聚合催化剂进行丙烯淤浆聚合时活性(以每克催化剂计)最高,达到30.4kg/(g.h);预聚合时,n(Al)∶n(Ti)=0.8～2.0时聚丙烯的颗粒粒径较均匀;随预聚合倍数的增大,DQ预聚合催化剂的活性(以每克钛计)提高。

Study on DQ Prepolymerization Catalyst for Propylene Polymerization

DQ prepolymerization catalyst was prepared using DQ catalyst.Effects of different DQ prepolymerization catalysts obtained under different conditions on propylene polymerization activity,polymerization kinetics and morphology of polymer particles were investigated.Improved morphology of polymer particles,steady polymerization kinetic curves and high activity of the catalyst are all greatly attributed to the use of prepolymerization catalyst.When DQ prepolymerization catalyst obtained at 10 ℃ is used in slurry polymerization,morphology of polymer particle is the best;when DQ prepolymerization catalyst obtained at 20 ℃ is used,activity of the catalyst(based on 1 g catalyst)is the highest,which can reach 30.4 kg/(g·h).In prepolymrization when n(Al)∶n(Ti)=0.8-2.0,morphology of polymer particle is more uniform.Along with the increasing prepolymerization degree the activity of DQ prepolymerization catalyst based on Ti improves.