Matsushita Yushu, Ohta Mitsuhiko, Suzuki Noritomo, Suzuki Makoto, Kitahara Ayane, Takano Atsushi
Toyota Physical and Chemical Research Institute, Yokomichi 41-1, Nagakute, Aichi 480-1192, Japan.
Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
ACS Nano. 2024 Jul 2;18(26):17135-17144. doi: 10.1021/acsnano.4c03782. Epub 2024 Jun 19.
Two-dimensional tiling manners as cross-sectional views of cylindrical domain assembly formed by pentablock quarterpolymers of the ABCBD type in bulk were investigated. Several binary and ternary blends from three mother polymers having different ϕ/ϕ ratios (ϕ and ϕ are the volume fractions of the B and B blocks, respectively) represent nonperiodic but ordered triangle/square tilings, where the / ratios ( and are the numbers of triangles and squares in the observed area, respectively) are all close enough to the theoretical value of 4/√3 ≑ 2.31 for the dodecagonal quasicrystalline (DDQC) state, irrespective of the total number of polygons. The TEM images, having almost the same / ratios, were proved to show 4- and 6-fold symmetries in terms of the angular appearance of equilateral polygon sides via image analyses. Among them, a ternary blend showed a nearly ideal random tiling pattern that is almost equivalent to the theoretically predicted tiling by SCFT. Moreover, the magnitude of phason strain estimated for a TEM image from the ternary blend was proved to be quite small when the observing area is narrow, while it deviates from the ideal quasicrystalline tiling with an increasing number of vertices in the observing area.
研究了由ABCBD型五嵌段四聚物在本体中形成的圆柱形区域组装体的二维平铺方式作为横截面视图。由三种具有不同ϕ/ϕ比（ϕ和ϕ分别是B和B'嵌段的体积分数）的母体聚合物组成的几种二元和三元共混物呈现出非周期性但有序的三角形/正方形平铺，其中/比（和分别是观察区域中三角形和正方形的数量）都足够接近十二边形准晶（DDQC）态的理论值4/√3 ≑ 2.31，而与多边形的总数无关。通过图像分析，具有几乎相同/比的TEM图像被证明在等边多边形边的角外观方面呈现出四重和六重对称性。其中，一种三元共混物呈现出几乎理想的随机平铺图案，几乎等同于SCFT理论预测的平铺。此外，当观察区域较窄时，从三元共混物的TEM图像估计的相子应变大小被证明相当小，而随着观察区域中顶点数量的增加，它偏离了理想的准晶平铺。
