摘要
研究开发了一种新型非茂负载聚烯烃催化剂———CpTi(dbm)Cl2 /MgCl2 /THF ,分析了该催化剂的结构特征 ,研究了该催化剂的乙烯聚合活性与催化剂的组成和结构间的关系。结果表明 ,用共沉淀方法制备的MgCl2具有较大的比表面积和孔体积。CpTi(dbm)Cl2 同MgCl2 作用后 ,催化剂中的CpTi(dbm)Cl2 仍保持了原来的化学结构 ,而活化了的MgCl2 也仍然基本保持原有的晶型 ;载体型催化剂的孔体积和比表面积随着Mg/Ti比的增加而增加 ;Mg/Ti比影响载体型催化剂粒子形态、分散性以及催化活性随着Mg/Ti比增加 ,催化剂的粒子形态和分散性提高 ,催化活性线性地增加 ,MgCl2 对Ti生成活性中心起良好的化学改性作用。
A novel non-metallocene supported catalyst, CpTi(dbm)Cl 2/ MgCl 2/THF was prepared by co-precipitation and characterized by means of elemental analysis, XRD, BET and SEM technique. The results indicate that the Mg/Ti ratio has considerable influence on the polymerization activity and physical structure of the catalyst. The catalytic activity of polymerization increase with the Mg/Ti ratio within the experimental range, and the surface area, pore volume and flowability of the supported catalyst increase with the Mg/Ti ratio also. In supported catalyst, the chemical structure of CpTi(dbm)Cl 2 and the crystal structure of MgCl 2 are not changed. The effect of MgCl 2 to CpTi(dbm)Cl 2 is discussed, which suggest that the activity of Ti can be improved via the chemical action of Mg to Ti.
出处
《化工进展》
EI
CAS
CSCD
北大核心
2003年第9期976-979,共4页
Chemical Industry and Engineering Progress
