Self-assembling, macroscopically oriented, polymer filaments; a doubly nematic organogel.
Self-assembling, macroscopically oriented, polymer filaments; a doubly nematic organogel.
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自组装、宏观定向的聚合物长丝；
DOI：
10.1039/c8sm01638k
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发表时间：
2018
期刊：
影响因子：
3.4
通讯作者：
Gleeson HF
中科院分区：
文献类型：
--
作者：
Gleeson HF
液晶中的纳米级相分离和自组织导致形成显著的分级结构。存在螺旋形纳米丝结构的若干实例，包括螺旋形扭曲-弯曲（NTB）相、B4相和由B4相形成的液晶凝胶。渗透到软固体中的聚合物样结构的形成及其层次结构都很吸引人，尤其是因为可以与自然发生的结构进行类比。在这里，我们报告了一个非常简单的二元系统形成的非对称BC分子和棒状液晶，5CB。纯聚核系统表现出两种不同的液晶相，一种是黑色的，另一种是黑色的。在非常低浓度的BC材料（5-10%）下，该二元体系自发地自组装成由纳米级细丝形成的软固体，所述纳米级细丝通过其微环境排列。宏观上，软固体显示出与聚合物和凝胶相关的行为。有趣的是，丝的亚微米尺度结构似乎与自然界中的一些有组织的纤维结构（例如甲壳素、纤维素、昆虫角质层、植物细胞壁）非常相似，我们将其归因于在取向液晶环境中的自组装和自组织。细丝的纳米级结构没有显示出可以与螺旋有序到几十纳米的长度尺度相关联的特征。然而，X射线数据表明，一个亚稳的矩形柱状相，这是高度有序的一个维度最初的形式，改变到一个六方晶格的时间尺度上的几十分钟。
Nanoscale phase separation and self-organisation in liquid crystals leads to the formation of remarkable hierarchical structures. There are several examples of heliconical nanofilament structures including in the nematic twist-bend (NTB) phase, the B4 phase and liquid crystal gels formed from the B4 phase. Both the formation of the polymer-like structures that permeate the soft-solids and their hierarchical structures are fascinating, not least because of the analogies that can be drawn with naturally-occurring structures. Here, we report a remarkably simple binary system formed from a non-symmetric BC molecule and the rod-like liquid crystal, 5CB. The pure bent-core system exhibits both nematic and dark conglomerate liquid crystal phases. At very low concentrations of the BC material (5–10%) this binary system spontaneously self-assembles into a soft solid formed from nanoscale filaments that are aligned by their nematic environment. Macroscopically, the soft solid shows behaviour that can be associated with both polymers and gels. Interestingly, the sub-micron scale structure of the filaments appears remarkably similar to some organised fibrous structures in nature (e.g. chitin, cellulose, insect cuticle, plant cell walls) something we attribute to self-assembly and self-organisation in an aligned liquid crystalline environment. The nanoscale structure of the filaments shows no features that can be associated with heliconical ordering down to length scales of tens of nanometers. However, the X-ray data suggest that a metastable rectangular columnar phase which is highly ordered in one dimension initially forms, changing to a hexagonal lattice on a timescale of tens of minutes.
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热致聚醚的流变学和流动诱导液晶相变
影响因子：
4.5
作者：
D. Heberer;J. Odell;V. Percec
通讯作者：
V. Percec
了解暗砾岩相纳米结构的异常重组。
DOI：
10.1103/physreve.91.042504
发表时间：
2015
期刊：
Physical review. E, Statistical, nonlinear, and soft matter physics
影响因子：
--
作者：
Nagaraj M
通讯作者：
Nagaraj M
影响因子：
3.4
作者：
Goertz, Verena;Southern, Christopher;Goodby, John W.
通讯作者：
Goodby, John W.
影响因子：
13.6
作者：
Kim H;Ryu SH;Tuchband M;Shin TJ;Korblova E;Walba DM;Clark NA;Yoon DK
通讯作者：
Yoon DK