【作者】 王卓识；

【导师】 金龍一；

【作者基本信息】 延边大学 ， 有机化学， 2014， 博士

【摘要】 获得纳米尺寸的新型超分子材料以及研究这些结构的性质受到人们的广泛关注,由刚性芳香核及柔性链组成的刚棒-线团三嵌段低聚物能在纳米尺度上自组装出多种纳米液晶超分子结构。本论文设计合成了一系列T型,H型,直线型的刚棒-线团三嵌段液晶低聚物,并研究了这些分子在固态、液晶态和溶液中的自组装行为,主要讨论了在刚柔界面引入支链对这类三嵌段液晶低聚物自组装结构的影响。对含有二苯并吩嗪的T型刚棒线团三嵌段低聚物,从改变刚棒末端的聚环氧乙烷链长度,改变刚棒顶端烷基链的长度,在刚棒和柔性链界面引入甲基等支链方面对其自组装结构的影响进行了研究,研究结果表明：(1)随着聚环氧乙烷链的增长,分子固态时的自组装结构由层状到矩形柱状；(2)T型刚棒中心引入不同长度的烷基链,使分子自组装结构形成了六方穿孔层状结构或倾斜柱状结构；(3)随着T型分子刚柔界面侧甲基的引入,固态时自组装结构由层状结构、矩形柱状结构到三维体心四方结构。对于一系列π-共轭的倾斜的H型刚棒-线团低聚物自组装行为的研究结果表明：(1)H型分子随着柔性链的增长,固态时分子的自组装结构由层状到倾斜柱状；(2)随着H型分子刚柔界面侧甲基的引入,固态时自组装结构由一维层状,二维倾斜柱状到三维体心四方结构。对于在刚柔界面含有侧甲基的四个系列的直线型刚棒-线团三嵌段液晶分子,通过调控柔性链体积分数和刚棒嵌段中心支链的长度,可以在液晶态时控制三维超分子纳米结构的形成,研究结果表明：随着刚柔界面甲基支链的引入,液晶态时自组装结构由六方穿孔层状结构到六方紧密堆积结构、由矩形柱状结构到体心四方结构、由六方穿孔层状结构到双连续立方结构、由六方穿孔层状结构到体心四方结构、由倾斜柱状结构到体心四方结构。更多还原

【Abstract】 The development of novel supramolecular materials with nanometer-scale architectures and these architectures’properties are currently of great interest in molecular design. Liquid crystalline assemblies of Rod-coil tri-block oligomers containing rigid rod segment and flexible coils(rod-coil molecules)provide a rich variety of different liquid crystalline structures with nanoscale dimensions. This thesis mainly discusses the self-assembly behaviors at solid state, liquid crystalline state and in solution of T-shaped, H-shaped and linear shaped rod building block oligomers, as well as the influence of side chain of molecular on the self-assembly behaviors of such tri-block oligomers.T-shaped coil-rod-coil tri-block oligomers, consisting of a dibenzo[a,c]-phenazine unit were synthesized and the self-assembling behavior of these molecules was investigated in the crystalline phase. We summarize the influence on the self-assembly structures of the T-shaped rod-coil oligomers by changing length of the alkoxyl chains at the end of the rod; the length of alkyl chains in the center of the rod; introduction of lateral methyl groups attached to the surface of rod and coil segments. The experimental results reveal that the length of the flexible PEO coil chain influence construction of various supra-nanostructures from lamellar structure to rectangular columnar structure. It is also shown that introduction of different length of alkyl side chain groups in the backbone of the T-shaped molecules affect the self-organization behavior to form hexagonal perforate layer or oblique columnar structures. In addition, lateral methyl groups attached to the surface of rod and coil segments, dramatically influence the self-assembling behavior in the crystalline phase. T-shaped molecules containing a lateral methyl group at the surface of rod and PEO coil segments, self-assemble into3D body-centered tetragonal structures in the crystalline phase, while molecules without a lateral methyl group based on PEO coil chain self-organize into2D oblique columnar crystalline structures.A class of π-conjugated, skewed H-shaped oligomers was synthesized and the self-assembling behavior of these molecules was investigated in the crystalline phase. The results indicates that that the length of the flexible PEO coil chain influence construction of various supra-nanostructures from lamellar structure to oblique columnar structure. H-shaped molecule containing a lateral methyl group at the surface of rod and PEO coil segments, self-assembles into3-D body-centered tetragonal nanostructures in the crystalline phase, while molecules without a lateral methyl group based on PEO coil chain self-organize into1-D lamellar structure or2-D columnar nanostructures.Four categories of linear-typed molecules with lateral methyl groups in the surface of rod and coil segments self-assemble into3-D assemblies in the liquid crystalline mesophase, depending on the the length of poly(ethylene oxide) coil or lateral chain in the center of the rod. The experimental results reveal that the molecules containing a lateral methyl group at the surface of rod and PEO coil segments, self-assembles into3-D hexagonal close-packed structure or3-D body-centered tetragonal micelle or3-D bicontinuous cubic nanostructure in the liquid-crystalline phase, while molecules without a lateral methyl group based on PEO coil chain self-organize into1-D lamellar structure or2-D columnar nanostructures.更多还原