论文部分内容阅读
本文对一种典型的反应法制聚乙烯高效催化剂的各步反应产物进行了研完:第一步氯化镁加乙醇反应,生成醇合物MgCl_2·nC_2H_5OH,其作用是将氯化镁晶格破坏;第二步加烷基铝,第三步加四氯化钛,其作用是与醇合物中的醇反应使之溶解,重新生成高分散的氯化镁微晶,活性组份钛化合物高度分散在氯化镁微晶表面上,故催化剂具有高活性。用这种反应法制得的高效催化剂,载体分散度高,内部孔隙多,有利于传质,因而比一般研磨法制得的高效催化剂聚合收率高。X光衍射发现在其他一些聚乙烯高效催化剂中也存在微晶MgCl_2,说明它们的高活性机理是类似的。
In this paper, a series of reaction products of typical high-efficiency polyethylene catalysts were studied. The first step is the reaction of magnesium chloride with ethanol to form alcogel MgCl 2 · nC 2 H 5 O 5, which destroys the crystal lattice of magnesium chloride. The second step Add aluminum alkyl, the third step plus titanium tetrachloride, whose role is to react with the alcohol in the alcohol to dissolve, regenerated high-dispersion magnesium chloride crystallites, the active ingredient titanium compounds are highly dispersed in the magnesium chloride crystallite surface Therefore, the catalyst has high activity. The efficient catalyst prepared by the reaction method has high carrier dispersion degree and more internal pores, which is favorable for mass transfer and thus has higher polymerization yield than the high-performance catalyst prepared by the ordinary milling method. X-ray diffraction showed that there were also microcrystalline MgCl 2 in some other polyethylene efficient catalysts, indicating that their high activity mechanism is similar.