给电子体在制备烯烃聚合NdCl_3载体催化剂中的作用

THE ROLE OF THE DONOR IN PREPARING OF NdCl_3 SUPPORTED CATALYST FOR OLEFINS POLYMERIZATION

Martin以无水稀土氯化物为载体,与磷酸三丁酯(TBP)在庚烷溶剂中反应制得LnCl_3/TBP/TiCl_4载体催化剂,其中以NdCl_3为载体的催化剂对乙烯聚合有很高活性,但对TBP的作用和载钛结构涉及较少。NdCl_3为链状晶体结构,不同于层状晶体结构的MgCl_2和TiCl_3(α和δ型)。我们对NdCl_3/EtOH/TiCl_4催化剂进行了较为详细的研究,并与MgCl_2/EtOH/TiCl_4催化剂进行比较。

It has been investigated that the role of donor such as tributyl phosphate (TBP) and ethyl benzoate (EB) in preparing of NdCl3 supported catalyst for olefins polymerization. The surface complexes were produced when the NdCU reacted with TBP and EB. There is a TiCl4/ TBP complex occurred in NdCl3/TBP/TiCl4 catalyst, whereas only the complex of EB with NdCl3 was discovered in NdCl3/EB/TiCl4 catalyst. The polymerization activity of above mentioned two kinds of catalysts for ethylene is much higher than that for propylene. The kinetic curve of polymerization for ethylene is of the decay-type with NdCl3/TBP/TiCl4 catalyst. The interaction between NdCl3 and MgCl3 supports occurred when the NdCl3 and MgCl2 were grounded together, which accelerates the breaking of supports. A higher activky of co-support NdCl3-MgCl2 catalyst for olefins polymerization was obtained.