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超分子聚合物被认为是一种新型的动态材料,对超分子聚合过程的研究不仅有助于理解自组装规律,而且为开发智能材料提供理论支持.研究了对亚苯基桥联的双脲基嘧啶酮(UPy)衍生物M1～M3的四重氢键超分子聚合.这些单体分子之间的唯一区别是其间隔基(寡聚乙二醇)的长度不同.通过测试随单体浓度变化的1HNMR,NOESY和粘度等研究了这些单体分子基于环链平衡的超分子聚合行为.结果表明间隔基长度对开环超分子聚合过程有显著影响.其原因是环状单体中亚苯基与二聚UPy之间的π-π相互作用强度不同.具有最短间隔基的M1缺乏π-π作用,而具有最长间隔基的M3具有较弱的π-π作用,因此二者的临界聚合浓度都较低;相比之下,间隔基长度适中的M2具有较强的π-π作用,从而导致其有较高的临界聚合浓度(189 mmol·L-l).最后,进一步研究了M1～M3与缺电子环番“blue-box”之间的相互作用,显示只有M3与环番发生主客体作用.该模型促进了对分子结构与超分子聚合之间紧密关系的认识,这对精确调控超分子聚合以及开发定制材料都具有重要意义.“,”Supramolecular polymers are regarded as a new kind of dynamic materials.The study of supramolecular polymers not only helps to understand the law of self-assembly,but also provides theoretical support for the development of smart materials.Herein,three dioxyphenylene bridged ditopic ureidopyrimidinone(UPy)derivatives M1～M3 are studied.These molecules could undergo supramolecular polymerization via quadruple hydrogen bonding.The only difference in their struc-ture is the length of the oligo(ethylene oxide)chain as spacers.The supramolecular polymerization based on ring-chain equi-librium of these molecules were studied by a series of experiments including concentration-dependent 1H NMR,NOESY,and viscosity measurement,which showed that the spacer length has a big impact on the ring-opening supramolecular polymeriza-tion process.And the main reason for this is the different strengths of π-π interaction between the dioxyphenylene unit and the dimerized UPy motif in the cyclic monomer form.M1 with the shortest spacer lacks this kind of π-π interaction while M3 with the longest spacer possesses a weak π-n interaction,both leading to small value of CPCs.By contrast,M2 with a moderate length of spacer has a strongπ-πinteraction,resulting in a high CPC value(189 mmol·L-1).Finally,the host-guest complexa-tion between M1～M3 with the π-electron deficient bipyridinium-based cyclophane “blue-box” were further investigated,which shows that only M3 could perform host-guest complexation.From this interesting model,new insight into the relation-ship between molecular structure and supramolecular polymerization is discovered,which is important for creating tailor-made supramolecular polvmeric materials.