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采用经预聚合处理的ＭｇＣｌ２负载的钛系催化剂进行乙烯气相聚合和淤浆聚合比较．乙烯淤浆聚合其表观动力学呈现为加速型或渐升衰减混合型，而气相聚合则为衰减型．在聚合前期阶段，气相聚合速度明显高于淤浆聚合速度．这样的差别是由于淤浆聚合中明显存在着单体在颗粒中扩散受阻的影响，气相聚合中则存在过热现象．测定了两种聚合方式中催化剂的钛价态，结果表明气相聚合条件下钛的价态分布比淤浆聚合更大程度倾向于低价态．催化剂预聚合温度和预聚合产率对气相聚合活性及表观动力学行为的影响表明预聚合工艺是气相聚合反应平稳控制有效技术．
Adopting pre-polymerized MgCl 2 -supported titanium-based catalyst for ethylene gas phase polymerization and slurry polymerization comparison. The apparent kinetics of ethylene slurry polymerization is either accelerating or gradual decay mixing, while gas-phase polymerization is decaying. In the early polymerization stage, the gas phase polymerization rate is significantly higher than the slurry polymerization rate. This difference is due to the apparent presence of monomer diffusion in the particles in the slurry polymerization hindered the influence of gas phase polymerization overheating phenomenon. The titanium valences of the catalysts in the two polymerization modes were determined. The results show that the valence distribution of titanium in the gas phase polymerization tends to be lower than that of the slurry polymerization. The influence of catalyst prepolymerization temperature and prepolymerization yield on gas-phase polymerization activity and apparent kinetic behavior indicates that prepolymerization is an effective technique for smooth control of gas-phase polymerization.