Molecular structure modulated properties of azobenzene-substituted polydiacetylene LB films: Chirality formation and thermal stability
Molecular structure modulated properties of azobenzene-substituted polydiacetylene LB films: Chirality formation and thermal stability
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偶氮苯取代聚二乙炔LB膜的分子结构调节特性：手性形成和热稳定性
DOI：
10.1016/j.polymer.2010.03.029
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发表时间：
2010-05
期刊：
影响因子：
4.6
通讯作者：
Iwamoto, Mitsumasa
中科院分区：
文献类型：
--
作者：
Manaka, Takaaki;Zou, Gang;Zhang, Qijin;Wang, Yali;Kohn, Hideki;Iwamoto, Mitsumasa
制备了三种新型偶氮苯取代的二乙炔单体（DA 1、DA 2和DA 3）的LB膜，并通过紫外-可见（UV-vis）光谱和圆二色性（CD）光谱研究了它们的光学和手征性质。非手性DA 1分子可以通过偶氮苯部分的过度拥挤堆积形成手性LB膜，而非手性DA 2和DA 3分子则不能。当暴露于左旋或右旋圆偏振紫外光（CPUL）时，观察到聚合的DA 1（PDA 1）和DA 2（PDA 2）LB膜的偶氮苯发色团和聚二乙炔链的引人注目的左旋或右旋（相反）CD信号。然而，在这种情况下，DA 3 LB膜几乎不能聚合，并且只能观察到偶氮苯发色团的相反CD信号。结果表明，分子间的空间位阻和偶氮苯生色团的不规则排列不利于聚二乙炔骨架的拓扑聚合和手性形成。进一步研究了热处理对上述三种LB膜超分子手性的影响。强的集体非共价相互作用（π-π堆积）被认为是手性超分子组装体热稳定性的原因。
Langmuir–Blodgett (LB) films of three novel azobenzene-substituted diacetylene monomers (DA1, DA2 and DA3) were fabricated and their optical and chiroptical properties were investigated in detail by ultraviolet–visible (UV–vis) spectra and circular dichroism (CD) spectra. Achiral DA1 molecules could form chiral LB films through overcrowded packing of the azobenzene moiety, while achiral DA2 and DA3 molecules not. When exposed to left-or right-handed circular polarized UV light (CPUL), striking left- or right-handed (opposite) CD signals for azobenzene chromophores and polydiacetylene chains were observed for the polymerized DA1 (PDA1) and DA2 (PDA2) LB films. However, DA3 LB films could hardly be polymerized in this case, and only striking opposite CD signals for azobenzene chromophores could be observed. It was demonstrated that the intermolecular steric hindrance and irregular arrangement of azobenzene chromophores were not favorable for the topo-polymerization and chirality formation of polydiacetylenes backbone. Further, the effects of thermal treatment on the supramolecular chirality of above three LB films were studied. Strong collective noncovalent interactions (π–π stacking) were believed to be responsible for the thermal stability of chiral supramolecular assemblies.
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DOI：
10.1016/b978-0-12-391927-4.10024-6
发表时间：
1985
期刊：
The European Physical Journal C
影响因子：
--
作者：
J. Israelachvili
通讯作者：
J. Israelachvili
影响因子：
3.9
作者：
Guijun Wang and;R. Hollingsworth
通讯作者：
Guijun Wang and;R. Hollingsworth
影响因子：
1.3
作者：
M. Ivanov;I. Naydenova;T. Todorov;L. Nikolova;T. Petrova;N. Tomova;V. Dragostinova
通讯作者：
M. Ivanov;I. Naydenova;T. Todorov;L. Nikolova;T. Petrova;N. Tomova;V. Dragostinova
DOI：
10.1039/f29767201525
发表时间：
1976-01-01
期刊：
JOURNAL OF THE CHEMICAL SOCIETY-FARADAY TRANSACTIONS II
影响因子：
--
作者：
ISRAELACHVILI, JN;MITCHELL, DJ;NINHAM, BW
通讯作者：
NINHAM, BW
影响因子：
3.3
作者：
Spitz, C;Dähne, S;Abraham, HW
通讯作者：
Abraham, HW