聚离子液体作为吸附材料的研究进展

聚离子液体(Polymeric ionic liquid,PIL)兼具离子液体和聚合物的双重优点,克服了离子液体在吸附过程中无形貌、高粘度、难回收及其使用中易流失等问题。通过聚合物设计和制备,不仅可以得到各种结构、尺寸和形貌的PIL材料,还可以提高PIL中离子液体功能基团的利用率。因此,PIL作为一类新型的高分子吸附材料迅速成为分离领域的热点。在介绍PIL的性质、分类和主要合成途径的基础上,总结了国内外近年来PIL在水相吸附中的研究进展。主要讨论了不同聚合物结构,如线性、超支化、交联结构等,对PIL吸附有机吸附质的影响,并分析了PIL功能基团与不同吸附质之间的相互作用机制,如离子交换、静电作用、氢键以及π-π堆叠等。最后,总结了离子液体功能基团和吸附剂结构与PIL吸附效果之间的关系,并对PIL吸附材料的发展进行了展望。

Recent Advances of Polymeric Ionic Liquids as Adsorbents

Polymeric ionic liquid (PIL)combines the advantages of both ionic liquid and polymer,and can over-come the problems during the use of ionic liquids,such as lack of morphology,high viscosity,inconvenient recovery and environmental risk by the loss of ionic liquid in water.By the design of polymer structure and preparation proce-dure,the PIL adsorbents with highly utilizable binding sites and different morphologies and shapes can be obtained. Based on the above advantages,PIL receive worldwide attentions in separation field.In this review,the properties, classification,and synthetic route of PIL are described in detail.Then their applications in adsorption fields in aqueous phase are summarized.The influence of PIL structure,such as linear,cross-linked and highly branched structure on the adsorption capacity is discussed emphatically.Moreover the adsorption interactions such as ion-exchange,H-bon-ding,electrostatic interaction andπ-πstacking are also analyzed.Consequently,the relationship between the functio-nal groups of ionic liquids,the material structure and the adsorption capability is summarized,and the further develop-ment of PIL adsorbents is proposed as well.