近年來，小分子凝膠被廣泛作為基質，透過凝膠與無機物的二次作用力，合成出各種不同結構的複合材料，如螺旋、纖維和絲狀等。此種新穎的有機-無機材料，深受化學界重視。為了合成出此種新穎的複合材料，我們研究合成出光學活性凝膠體分子(cholesteryl-pyridine-carbamate, CPC)，將其分子設計上導入pyridine基團、膽固醇基團與胺酯基，藉由分子間的二次力鍵結，誘導CPC分子在有機溶劑中形成超分子凝膠體。由SEM與TEM結果顯示，此CPC分子可自組裝成奈米纖維進而組織成三維網絡的超分子凝膠(supramolecular gel)；透過XRD與分子模擬程式分析，說明超分子有機凝膠以pyridine基團及胺酯基為重疊作錯位排列。並利用FTIR與變溫1H-NMR証實分子間氫鍵和凡德瓦力為凝膠形成的主要作用力。透過凝膠化測驗可得知最小臨界凝膠濃度。進一步的以超分子凝膠為基質(matrix)，利用分子上的孤對電子對與銀離子產生螯合作用，以光化學反應還原吸附在凝膠纖維上的奈米銀粒子，使形成三維網絡的奈米銀膠。其次，凝膠分子上的pyridine 基團能與sebacic acid 形成氫鍵錯合物，經DSC、POM證實其具有熱變性液晶性質。

關鍵字：自組裝、超分子凝膠、氫鍵、模板、奈米銀粒子、液晶。

Low-molecular-weight-gelators (LMWGs) have recently been used as a matrix to construct a kind of composite materials of different shapes or structures such as helices, fibers, tapes or tubes through the secondary force interaction between gelators and inorganic materials. In order to develop this kind of novel composite materials, we synthesized and characterized the novel chiral molecule cholesteryl-pyridine-carmbamate (CPC) containing pyridine, cholesteryl and urethane group. Supramolecular organogels formed due to the secondary forces between CPC molecules and solvents. From the results of SEM and TEM analysis, self-assembly of CPC molecules form highly ordered nanofibers. Further aggregation of the ordered constructions forms 3D entangled network. XRD and molecular simulation show that arrangement of supramolecular organogel is mainly through the overlap of pyridine and urethane groups. Results of FTIR and thermal changeable 1H-NMR show that intermolecular hydrogen bond and van der Waals forces are the key factors for the formation of gels in DMSO. Furthermore, supramolecular gels were used as polymer matrices to coordinate silver ions. Silver nanoparticles embedded self-assembled nanofibers were further fabricated via photoreduction of silver ions. CPC forms complex with sebacic acid through hydrogen bond between pyridine and carboxylic group. Thermotropic liquid crystal phases of the complex were confirmed using DSC and POM analysis.
Keywords：self-assembly, supramolecular gels, hydrogen bond, matrices,silver nanoparticles, liquid crystals.

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