Frustrated bilayer smectic phase in main-chain polymers with two different spacers
Frustrated bilayer smectic phase in main-chain polymers with two different spacers
复制标题
具有两种不同间隔基的主链聚合物中的受抑双层近晶相
DOI：
10.1051/jp2:1994149
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
K. Simizu
中科院分区：
文献类型：
--
作者：
J. Watanabe;Y. Nakata;K. Simizu
我们研究了主链型聚合物形成的近晶相的结构特征，在主链型聚合物中，介晶的联苯基团由两个不同的奇数脂肪基团以规则交替的方式相连。这项研究的第一个有趣的结果是，两种不同类型的层结构的形成取决于两个脂肪族间隔基的长度的不同。在具有两个间隔基的长度差别很小的聚合物中，作为两个不同间隔基的随机混合的结果形成单层结构。相反，如果存在足够大的长度差异，两个不同的间隔体参与到不同的层中，因此近晶相似乎具有双层特征。第二个有趣的结果是，双层近晶相在平行于层的方向上以不寻常的密度调制伪装成受挫结构。这种受挫结构被解释为是自发极化的二维逃逸造成的
We have studied the structural characteristics of the smectic phases formed by the main-chain type of polymers in which the mesogenic biphenyl moieties are linked by two different odd-numbered aliphatic spacers in a regularly alternate fashion. The first interesting result of this study is that the two different types of layer structures are formed depending on the difference in the lengths of two aliphatic spacers. In the polymers with the two spacers having a small difference in their lengths, the single layer structure is formed as a result of the random mixing of the two different spacers. In contrast, if there is a sufficiently large difference in lengths, the two different spacers participate into different layers and so the smectic phase appears to have a bilayer character. The second interesting result is that the bilayer smectic phase pretends the frustrated structure with the unusual density modulation in the direction parallel to the layer. This frustrated structure has been explained as resulting from a twodimensional escape of the spontaneous polarization