Abstract This study focuses on gas-phase polymerization of ethylene using the titanium-based Ziegler–Natta catalysts prepared from different magnesium sources including MgCl2 (Cat A), magnesium powder (Cat B), and Mg(OEt)2 (Cat C). During polymerization, different cocatalysts were also used. It was found that Cat C with triethylaluminum as a cocatalyst exhibited the highest activity. This was likely attributed to optimal distribution of active sites on the catalyst surface. It can be observed by increased temperature in the reactor due to highly exothermic reaction during polymerization. By the way, the morphologies of the polymer obtained from this catalyst were spherical, which is more preferable. Besides the catalytic activity, crystallinity and morphology were also affected by the different magnesium sources used to prepare the catalysts.

中文翻译：

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乙烯在不同镁源制备的钛基齐格勒-纳塔催化剂上的气相聚合

摘要 本研究的重点是使用钛基齐格勒-纳塔催化剂对乙烯进行气相聚合，该催化剂由不同的镁源制备，包括 MgCl2 (Cat A)、镁粉 (Cat B) 和 Mg(OEt)2 (Cat C)。在聚合过程中，还使用了不同的助催化剂。发现以三乙基铝为助催化剂的Cat C表现出最高的活性。这可能归因于催化剂表面活性位点的最佳分布。由于聚合期间的高度放热反应，可以通过反应器中的温度升高来观察到。顺便说一下，由该催化剂得到的聚合物的形态是球形的，这是更优选的。除了催化活性外，结晶度和形态也受到用于制备催化剂的不同镁源的影响。