Study on the Structure of Host-Guest Supramolecular Polymers
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- 作者：Claudia Leggio ; Massimiliano Anselmi ; Alfredo Di Nola ; Luciano Galantini ; Aida Jover ; Francisco Meijide ; Nicolae Viorel Pavel ; Victor Hugo Soto Tellini ; José ; Vá ; zquez Tato
- 刊名：Macromolecules
- 出版年：2007
- 出版时间：August 7, 2007
- 年：2007
- 卷：40
- 期：16
- 页码：5899 - 5906
- 全文大小：198K
- 年卷期：v.40,no.16(August 7, 2007)
- ISSN：1520-5835
文摘
A detailed characterization of a host-guest supramolecular copolymer, formed by adamantaneand 
mages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-cyclodextrin dimers (Ad2 and mages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD2, respectively) in aqueous solution, has been carried out by combiningsmall-angle X-ray scattering and light scattering experiments with molecular dynamics (MD) and Monte Carlo(MC) simulations. First, the solutions of the monomers were studied by a straightforward analysis of the scatteringdata. Afterward, the complex given by Ad2 and two mages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-cyclodextrin molecules was investigated by correlatingscattering results and MD simulations, to characterize the host-guest linkage. Finally, a detailed interpretationof the polymer scattering data was achieved by MC simulations. These simulations were performed on a singlesupramolecular aggregate and, in view of its peculiar shape, the complete polymer structure was consideredwithout resorting to more general but simplified chain models. The comparison between simulations with andwithout excluded volume interaction points out that, at our ionic strength (sodium azide 150 mM), the polymeris close to the theta condition. Fits by reverse MC methods show that the polymer presents a shrunk conformationin solution, but it does not close in stable cyclic structures, as generally hypothesized for this kind of smalloligomer. However, a polymerization degree of about 8 (4 Ad2 and 4 mages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD2) was estimated which does not showany concentration dependence.