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首页> 外文会议>International symposium on macro- and supramolecular architectures and materials: Biological and synthetic systems >STRUCTURE AND FUNCTION OF POLYMERIC INCLUSION COMPLEX OF MOLECULAR NANOTUBES AND POLYMER CHAINS
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STRUCTURE AND FUNCTION OF POLYMERIC INCLUSION COMPLEX OF MOLECULAR NANOTUBES AND POLYMER CHAINS

机译：分子纳米管和聚合物链的聚合物包合物的结构和功能

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Various organic supramolecules with unique structures have attracted great interests of many scientists. Harada et al. prepared a polyrotaxane supramolecule in which cyclodextrin (CD) molecules of cyclic form were threaded on a polymer chain with bulky ends and then synthesized molecular nanotubes with the diameter smaller than carbon nanotubes by crosslinking the adjacent CD units in the polyrotaxane. This molecular nanotube, highly soluble in several kinds of solvents such as water, has a constant inside diameter (0.45nm) and a longitudinal length of submicron order controllable by varying the length of the polyrotaxane. Owing to the infinitesimal inside diameter of the molecular nanotube, a polymer chain included in the nanotube has an extended conformation, such as a planar zigzag one, with no degrees of freedom other than a translational motion along its longitudinal axis. Therefore, the inclusion of a polymer chain into a molecular nanotube is entropically unfavorable and promoted by attractive interaction such as hydrophobic one between the chain and the nanotube. In other words, heating results in the dissociation of the polymer chain from the nanotube with recovery of the intrinsic entropy of random conformation as shown in Fig.1. Moreover the conformational entropy and inclusion interaction are roughly estimated to be proportional to the length of the nanotube and polymer chain. Consequently, the free energy changes drastically with inclusion or dissociation between a long molecular nanotube and polymer chain, which leads to a transitional behavior. We have recently investigated the inclusion complex formation between molecular nanotubes and polymer chains theoretically and experimentally As mentioned above, this polymeric supramolecular system has a feature that the inclusion-dissociation behavior becomes cooperative and sharp compared with the inclusion complex formation between cyclic molecule and small molecular compounds. And we have proposed some functional supramolecules such as insulated molecular wire and topological gel. In this chapter, we will introduce these theoretical and experimental works on the polymeric supramolecular system of molecular nanotubes and polymer chains.
机译：具有独特结构的各种有机超法吸引了许多科学家的极大兴趣。 Harada等。制备了一种多甲烷的Suprameolecule，其中环状形式的环糊精（CD）分子在具有体积末端的聚合物链上拧在聚合物链上，然后通过交联在多岩中的相邻的CD单元中的直径小于碳纳米管的分子纳米管。该分子纳米管高度可溶于几种溶剂如水，具有恒定的内径（0.45nm）和通过改变聚图横透明的长度来控制的亚微米顺序的纵向长度。由于分子纳米管的无限内部直径，包括在纳米管中的聚合物链具有延伸的构象，例如平面之字形α，除了沿其纵向轴线的平移运动之外的不自由度。因此，将聚合物链将聚合物链包含在分子纳米管中是熵上不利的，并且通过有吸引力的相互作用，例如链条和纳米管之间的疏水性。换句话说，加热导致来自纳米管的聚合物链的解离，随着随机构象的内在熵的回收，如图1所示。此外，构象熵和包合物相互作用大致估计与纳米管和聚合物链的长度成比例。因此，自由能量随着长分子纳米管和聚合物链之间的包含或解剖而变化，其导致过渡行为。最近我们已经调查分子的纳米管和聚合物链之间的包合配合物的形成理论和实验如上所述，该聚合超分子系统的特征在于具有环状分子和小分子之间的包合配合物的形成相比，夹杂物的解离行为变得合作和尖锐化合物。我们已经提出了一些功能性的超分子，例如绝缘分子线和拓扑凝胶。在本章中，我们将在分子纳米管和聚合物链的聚合物超分子系统上介绍这些理论和实验性。

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