2-D Columnar Assemblies of Diblock Rod-Coil Molecules Incorporating Cholesteryl Group
作者:Yang Liu、Yirong Pei、Zhuoshi Wang、Junjie Cui、Tie Chen、Jingzhe Xu、Long Yi Jin
DOI:10.14233/ajchem.2014.16021
日期:——
Rod-coil molecules have a strong tendency to self-organize into supra-molecular nanostructures in the bulk state. In this article, we report synthesis and self-assembling behaviour of rod-coil molecules 1-3, consisting of a biphenyl and cholesteryl group as a rod segment and poly(ethylene oxide) (PEO) with a degree of polymerization of 7, 12 and 17 coil segments. Self-organization behaviour of these molecules investigated by means of differential scanning calorimetry, thermal polarizing optical microscopy and small-angle X-ray scattering in the bulk state reveal that volume fraction of PEO coil segments containing alkyl chain of cholesteryl group dramatically influence the self assembling behaviour of rod building block in the liquid crystalline phase. Molecules 1-3 self-assemble into 1-D bilayered structures with different d-spacing according to the lengths of coil domains in the solid state. While, self-organized molecular structures transfer into oblique columnar structure for molecule 1 and 2 from the crystalline to the liquid crystalline phase, further increasing coil to rod volume fraction, molecule 3 self assemble into hexagonal columnar aggregate through p-p stacking of rod building blocks.
棒卷分子在体态下具有自组织成超分子纳米结构的强烈倾向。本文报告了杆卷分子 1-3 的合成和自组装行为。杆卷分子 1-3 由联苯基和胆固醇基作为杆段,聚合度为 7、12 和 17 的聚环氧乙烷(PEO)作为卷段。利用差示扫描量热法、热偏振光学显微镜和小角 X 射线散射法研究了这些分子在块状状态下的自组织行为,结果表明,含有胆固醇基烷基链的 PEO 线圈段的体积分数极大地影响了液晶相中杆状构件的自组装行为。分子 1-3 在固态下可根据线圈畴的长度自组装成具有不同 d 距的一维双层结构。分子 1 和分子 2 的自组织分子结构从结晶相转移到液晶相时变成了斜柱状结构,进一步增加了线圈与杆的体积分数,而分子 3 则通过杆构件的 p-p 堆积自组装成六角柱状集合体。