Modulation of Supramolecular Interactions of Urea-based Supramolecular Polymers via Molecular Structures  

作　　者：LU Zhiyi TANG Liming 

机构地区：[1]Key Laboratory of Advanced Materials, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beifing 100084, P. R. China

出　　处：《Chemical Research in Chinese Universities》2018年第5期849-856,共8页高等学校化学研究（英文版）

基　　金：Supported by the National Natural Science Foundation of China（No.21574074）, the National Basic Research Program of China（No.2014CB932202） and the Fund of Key Laboratory of Advanced Materials of the Ministry of Education, China （No.2017AML08）.

摘　　要：Linear bis-urea D230 series and branched tris-urea T403 series of supramolecular monomers were syn- thesized using low molecular weight polyetheramine D230, T403 and isocyanates with diverse functional groups. Rheological tests reveal that the materials possess special thermal and mechanical properties due to the strong hydrogen bonding interactions between terminal urea groups and the high flexibility of the polyetheramine middle segments. By enhancing the hydrogen bonding interactions through electronic effects of the substituted urea groups, the mechanical properties of the bulk material can be increased. Moreover, the branched T403 series with higher hy- drogen bonding density also shows better performance against D230 series with the same substituted urea groups. The presence of π-π stacking between the phenyl groups in samples with phenylurea residues, which complements the hydrogen bonding, was also confirmed by fluorescence spectroscopy, therefore resulting in a stronger supramolecular polymer network.Linear bis-urea D230 series and branched tris-urea T403 series of supramolecular monomers were syn- thesized using low molecular weight polyetheramine D230, T403 and isocyanates with diverse functional groups. Rheological tests reveal that the materials possess special thermal and mechanical properties due to the strong hydrogen bonding interactions between terminal urea groups and the high flexibility of the polyetheramine middle segments. By enhancing the hydrogen bonding interactions through electronic effects of the substituted urea groups, the mechanical properties of the bulk material can be increased. Moreover, the branched T403 series with higher hy- drogen bonding density also shows better performance against D230 series with the same substituted urea groups. The presence of π-π stacking between the phenyl groups in samples with phenylurea residues, which complements the hydrogen bonding, was also confirmed by fluorescence spectroscopy, therefore resulting in a stronger supramolecular polymer network.

关 键 词：UREA Hydrogen bonding π-π Stacking Structure and property RHEOLOGY 

分 类 号：O753.2[理学—晶体学] TQ225[化学工程—有机化工]