论文部分内容阅读
以Mg(OEt)2和TiCl4作为钛镁体系聚乙烯催化剂的代表，在不同反应条件下制备了Ti-Mg体系负载型聚乙烯催化剂，并用扫描电镜(SEM)技术对其亚微观结构进行研究，证实其具有分形特征。应用分形理论及其改进的盒子维法对催化剂的亚微观结构进行了详细的分析计算，给出了催化剂表面结构的分维数。结果发现：催化剂分维值Df随着催化剂表面的不规则度及催化剂内部孔隙的增多而增大，而其聚合活性与催化剂表面分维值的关系较为复杂，只有在适宜的催化剂分维值范围内, 才可获得较高的聚合活性。研究证明了分维值可作为比较两个分形无规则度对象的表征参量。
Ti (Mg (OEt) 2) and TiCl4 (TiCl4) were used as representatives of Ti-Mg system polyethylene catalysts. Ti-Mg system supported polyethylene catalysts were prepared under different reaction conditions and their submicroscopic structures were studied by scanning electron microscopy (SEM) Confirmed that it has fractal features. The fractal theory and its improved box dimension method were used to analyze and calculate the submicroscopic structure of the catalyst in detail. The fractal dimension of the catalyst surface structure was given. The results show that the fractal dimension Df increases with the irregularity of the catalyst surface and the increase of pores in the catalyst. The relationship between the polymerization activity and the fractal dimension of the catalyst surface is complex. Only in the range of suitable fractal dimension In order to obtain higher polymerization activity. The research proves that fractal dimension value can be used as a characterization parameter to compare two fractal irregularity objects.