Establishment of Self-assembled Rotaxane Ultrathin Film Chemistry

自组装轮烷单分子膜的制备建立了一种由紫精功能化的烷硫醇和α-环糊精(CD)组成的自组装轮烷单分子膜(轮烷-SAM)的简单制备工艺。用拟轮烷制备轮烷-SAM时，由于过量的Cd分子在电极表面的物理吸附，影响了轮烷-SAM的制备。相反，使用假轮烷的电位扫描方法可以简单地制备轮烷-SAM，因为CD分子在负电位下从电极表面解吸。合成和表征了三种含偶氮二(二苯并-24-冠-8醚)1的机械键合交联点的聚氨酯(PU0、PU11和PU33)，除PU0外，其余都是[3]轮烷结构。PU0和PU11可溶于DMF和DMSO，而PU33在这两种溶剂中均可溶胀，表明PU33通过机械键合交联形成了三维网状结构。从ATR-FT-IR测试结果来看，1的引入导致了PU中氨酯键部分之间以及氨酯键上的羰基与PU中铵单元之间的氢键断裂，这是由于1形成了[3]轮烷结构的空间位阻。PUS的热性能表明，玻璃化转变的比热随着PU33含量比的增加而增加，这表明PU33比PU0含有更多的非晶区。PU33在Tg后没有出现转变峰，而PU11出现了结晶和熔融的峰。动态粘弹性能测试也证实了PU11的玻璃化转变和熔体的热性能。

Preparation of a self-assembled rotaxane monolayerSimple fabrication technique of a self-assembled rotaxane monolayer (rotaxane-SAM) consisting of a viologen-functionalized Alkanethiol and a-cyclodextrin (CD) using potential sweep has been established. Use of a pseudorotaxane to prepare the rotaxane-SAM often suffers with physical adsorption of excess CD molecules onto electrode surface that interferes with fabrication of the rotaxane-SAM. In contrast, use of the potential sweep for the pseudorotaxane method results in simple fabrication of the rotaxane-SAM because of desorption of the CD molecules form the electrode surface at negative potential.Synthesis and characterization of polyurethanes cross-linked with a rotaxaneThree polyurethanes (PU0, PU11 and PU33) containing azobis (dibenzo-24-crown-8 ether) 1 as a molecule for a mechanical bonding cross-link point with a [3]rotaxane structure except PU0 were synthesized. PU0 and PU11 were soluble in DMF and DMSO whereas PU33 swelled in both the solvents, suggesting that PU33 forms a 3D-network structure via the mechanical bonding cross-links. From the result of ATR-FT-IR measurements, introduction of 1 causes break of hydrogen bonds between urethane bond moieties as well as between carbonyl of urethane bond and ammonium unit in the PUs due to steric hindrance of 1 forming the [3]rotaxane structure. Thermal properties of the PUs revealed that specific heats of glass-transitions increased with increase in the content ratio of 1, suggesting that PU33 contains more amorphous region than PU0. PU33 showed no transition peaks after Tg, whereas PU11 gave the peaks for crystallization and melt. Thermal properties of glass-transition and melt for PU11 were also confirmed by dynamic viscoelastic property measurement.