丁二烯聚合中铁系催化剂烷基铝作用的研究

Function of Aluminum Alky for Butadiene Polymerization with Alkyl Iron Catalyst System

研究了在２５℃加氢汽油介质中，铁系胶体催化剂［Ｆｅ（ｎａｐｈ）２Ａｌ（ｉＢｕ）３ＣＨ２＝ＣＨＣＨ２Ｃｌ］单组分、多组分按不同配比混合，非水体系电导率与浓度的关系，结合Ｔｙｎｄａｌ效应，聚合实验结果，得出Ａｌ（ｉＢｕ）３以缔合状态存在并解离成离子对；它同环烷酸亚铁的作用是形成胶核的主要反应；与氯丙烯反应生成的氯化异丁基铝，在胶核表面参与形成活性中心；由过量Ａｌ（ｉＢｕ）３解离的离子对形成的双电层结构，使胶粒保持相对稳定。催化剂各组分较佳配比对应稳定胶粒的形成；它具有颗粒小、均匀、较高的催化活性。催化体系加入丁二烯引起电导率下降表明活性中心是正离子性的。

The relationship was studied between nonaqueous system electroconductivity of single component and multicomponent mixed by different ratios of iron system colloidal catalyst [Fe(naph)_2-Al(i-Bu)_3-CH_2-CHCH_2Cl] and their concentration in hydrogenated gasoline medium at 25℃.And through Tyndall effect and polymerization experiment Al(i-Bu)_3 existed in associate state and was dissociated into ionpair.The reaction between Al(i-Bu)_3 and Fe(naph)_2 was the main reaction which formed colloidal core;while it reacted with chlorallylene,AIR4CH2=CHCH2Cl was yielded,it joined in the formation of active center on the surface of colloidal core.The excessive Al(i-Bu)_3 was dissociated into ionpair forming a double electrode layer,and the layer kept the colloidal particles relatively stable.The optimal component tatios of catalyst corresponded with the forming of stable colloidal particles which was tiny,uniform and of high catalytic activity.While butadiene was added to the catalytic system the electroconductivity was reduced.It showd that the active center was positive ionicity.