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Preparation of new FI-type catalyst for polymerization of ethylene

机译：新型用于乙烯聚合的FI型催化剂的制备

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A new FI-type Zr-based catalyst of bis[N-(3,5-dicumylsalicylidene)- anthracylaminato]zirconium(IV) dichloride was found to display a moderate ethylene polymerization activity of 42×104 g PE/mmol Zr. h with a viscosity average molecular weight (Mv) of 56×104 at the monomer pressure of 4 bars and temperature of 30 °C. HOMO (the highest occupied molecular orbital) and LUMO (the lowest unoccupied molecular orbital) energy level of the anionic phenoxyimine ligands, were calculated using HF/6-31G method. Plurality of the fused aromatic rings on the catalyst structure decreased the energy gap between the HOMO and LUMO, but could not increase the activity. The highest activity of the catalyst was obtained at about 30 °C following a sharp decrease at higher temperature. The catalyst showed the high activity at about [Al]:[Zr]=80000:1 molar ratio and further addition did not affect the activity of the catalyst. Experimental results revealed that low HOMO energy level is not a necessity to reach high activity of the catalyst. Despite low HOMO energy level, the prepared catalyst displayed moderate polymerization activity. Either the activity of the catalyst or the viscosity average molecular weight of the obtained polymer was affected by the hydrogen concentration slightly. However, activity of the catalyst showed higher sensitivity to amount of hydrogen and increased with increasing the hydrogen concentration. Higher monomer pressure increased productivity, crystallinity and the Mv values of the resulting polymer. Some specification of the obtained polymer was studied.
机译：发现一种新型的双[N-（3,5-二枯基水杨基亚基）-蒽基氨基]二氯化锆（IV）的FI型Zr基催化剂显示出42×104 g PE / mmol Zr的中等乙烯聚合活性。 h在4 bar的单体压力和30°C的温度下的粘均分子量（Mv）为56×104。使用HF / 6-31G方法计算阴离子苯氧基亚胺配体的HOMO（最高占据分子轨道）和LUMO（最低未占据分子轨道）能级。多个稠合的芳环在催化剂结构上减小了HOMO和LUMO之间的能隙，但是不能增加活性。在较高温度下急剧下降之后，在约30℃下获得催化剂的最高活性。催化剂在约[Al]：[Zr] = 80000：1摩尔比时显示出高活性，并且进一步添加不影响催化剂的活性。实验结果表明，低的HOMO能级不是达到催化剂高活性的必要条件。尽管HOMO能级低，但所制备的催化剂仍显示出适度的聚合活性。催化剂的活性或所得聚合物的粘均分子量均受氢浓度的轻微影响。然而，催化剂的活性显示出对氢量的更高的敏感性并且随着氢浓度的增加而增加。较高的单体压力提高了所得聚合物的生产率，结晶度和Mv值。研究了所得聚合物的某些规格。

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