超支化大分子桥联水杨醛亚胺钴催化剂催化乙烯低聚

以1.0代（1.0G）超支化大分子、水杨醛和CoCl₂·6H₂O为原料，依次经过希夫碱反应和络合反应合成了3种具有不同烷基链长度的新型超支化大分子桥联水杨醛亚胺钴催化剂。对目标产物的结构进行FT-IR、UV、MS及TG表征，考察了溶剂种类、助催化剂种类、反应温度、反应压力、Al/Co摩尔比等条件对超支化大分子桥联水杨醛亚胺钴催化剂催化乙烯低聚性能的影响。结果表明，超支化大分子桥联水杨醛亚胺钴催化剂催化乙烯低聚表现出良好的催化活性和高碳烯烃（C₁₀₊）的选择性。催化活性随反应温度和Al/Co摩尔比增加先增加后下降，随反应压力增加而增加。以甲苯为溶剂，在一氯二乙基铝（DEAC）活化下，当反应温度为25℃、反应压力为0.5 MPa、Al/Co摩尔比为500时，催化活性可达1.87×10⁵ g·（mol Co）^-1·h^-1，聚合产物中高碳烯烃的含量高达42.90%。

Ethylene oligomerization using hyperbranch-macromolecule-bridged salicylaldimine cobalt catalysts

Three novel hyperbranch-macromolecule-bridged salicylaldimine cobalt catalysts were synthesized by Schiff and complex reactions of 1.0G hyperbranched macromolecules, salicylaldehyde, and cobalt chloride hexahydrate, and were characterized by FT-IR, UV, MS and TG. The influences of solvent, co-catalyst, reaction temperature, reaction pressure, and Al/Co molar ratio on their catalytic performances in ethylene oligomerization were studied. The results showed that the hyperbranch-macromolecule-bridged salicylaldimine cobalt catalysts had excellent catalytic activities and selectivity for ethylene oligomerization of high carbon number olefins (C₁₀₊). The catalytic activity first increased and then decreased with the increase of reaction temperature and Al/Co molar ratio, however, it continuously increased with the increase of reaction pressure. The highest activity of 1.87×10⁵ g·(mol Co)^-1·h^-1 and 42.90% selectivity for high carbon number olefins were achieved under the condition of toluene as solvent, DEAC as co-catalyst, reaction temperature at 25℃, reaction pressure at 0.5 MPa, and Al/Co molar ratio at 500.