【摘要】 以用溶胶凝胶法制备的Fe/Si O2复合颗粒作为载体负载二氯二茂锆(Cp2Zr Cl2),用聚合填充法催化乙烯聚合制备了Fe/Si O2/PE复合颗粒。用扫描电镜、X射线能谱分析、红外光谱、电感耦合等离子体光谱仪、热重分析仪和激光粒度分析仪、凝胶渗透色谱等手段对复合颗粒进行了分析和表征。结果表明,Fe/Si O2复合颗粒外层Si O2包覆完整,可用作Cp2Zr Cl2的载体;Fe/Si O2/Cp2Zr Cl2催化剂体系在乙烯聚合过程中显示出较高的活性,可聚合得到Fe/Si O2/PE复合颗粒;催化活性组分在聚合过程中不会从Fe/Si O2复合颗粒上脱离,生成的聚乙烯在载体表面包覆良好;Fe/Si O2/PE复合颗粒在聚合过程中出现了明显的团聚;Fe/Si O2/Cp2Zr Cl2催化剂颗粒和Fe/Si O2/PE复合颗粒的形状均不规则,两者之间有复制效应;改变聚合时间和聚合压力可调节Fe/Si O2/PE复合颗粒中的Fe含量;用Fe/Si O2/Cp2Zr Cl2催化剂催化乙烯聚合得到的聚乙烯,分子量分布较窄。更多还原

【Abstract】 Fe/Si O2 composites were prepared by sol- gel method firstly and further on which zirconcene dichloride(Cp2Zr Cl2) was deposited to prepare a catalyst Fe/Si O2/Cp2 Zr Cl2. Then particulates of Fe/Si O2/PE composites were produced by polymerization filling technique with ethylene and the Fe/Si O2/Cp2 Zr Cl2catalysit. The obtained Fe/Si O2/PE composite particles were characterized by scanning electron microscopy(SEM), energy dispersive X- ray spectroscopy(EDX), infrared spectroscopy(IFR), inductively coupled plasma spectroscopy(ICP), thermal gravimetric analysis(TGA) and laser particle size analyzer,respectively. The results show that the Fe core was perfectly coated by a Si O2 layer for the Fe/Si O2 composites, which could act well as a supporter for the deposition of Cp2 Zr Cl2. The Fe/Si O2/Cp2 Zr Cl2catalyst showed a high activity for the ethylene polymerization process. PE chains grew and attached on the Fe/Si O2/Cp2 Zr Cl2composites gradually, until the Fe/Si O2 composites were entirely coated. Moreover, the Fe/Si O2/PE particles were found to agglomerate significantly during ethylene polymerization. Both the Fe/Si O2/Cp2 Zr Cl2catalysts and Fe/Si O2/PE composites had irregular shapes, and the latter tended to duplicate the shape of the former. The Fe content in the Fe/Si O2/PE composites can be adjusted by varying the time and pressure of the polymerization process. Finally, the range of the molecular mass distribution of the PEs produced by this process is narrow.更多还原