Creation of A Two-dimensional Mesoscopic Quasicrystal with Dodecagonal Symmetry from An ABC Star-shaped Terpolymer

用 ABC 星形三元聚合物创建具有十二角对称性的二维介观准晶体

基本信息

批准号：
17205021
负责人：
MATSUSHITA Yushu
金额：
$ 30.7万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2007
项目状态：
已结题

项目摘要

It is well-established that block copolymers with incompatible components form nanophase-separated structures in condensed system due to their self-assembling nature. Star-shaped terpolymers whose three polymer chains are branched at one junction point are known to construct anisotropic cylinder-like structures in bulk, since their junction points have to be aligned on one-dimensional lines. Bulk structures of two series of star-shaped terpolymers were studied in this work, i.e., I_<1.0>S_<1.0>P_x, I_<1.0>SyP_<2.0>(I:polyisoprene, S : polystyrene, P : poly (2-vinylpyridine), X, Y are variable parameters), Solvent-cast and annealed films were used as samples. Several periodic Archimedean tiling structures with regular polygons, (6.6.6), (4.8.8) and (4.6.12) were observed fro two series. A little more complex structure,(3.3.4.3.4)), was observed for the latter series and, furthermore, more complex tiling structure composed of triangles and squares has been observed with a light change of composition from the sample with(3.3.4.3.4). The diffraction pattern with dodecagonal symmetry was observed for the sample, though it did not have periodic unit cell, which is the evidence of the quasicrystal with dodecagonal symmetry. The size of the sides of polygons is about 50nm, which is hierarchically scaled-up size from calcogenide and dendron systems.

众所周知，具有不相容组分的嵌段共聚物由于其自组装性质而在凝聚体系中形成纳米相分离结构。已知星形三元共聚物的三个聚合物链在一个连接点处支化，可以大量构建各向异性的圆柱状结构，因为它们的连接点必须在一维线上对齐。本工作研究了两个系列星形三元共聚物的本体结构，即I_<1.0>S_<1.0>P_x，I_<1.0>SyP_<2.0>（I：聚异戊二烯，S：聚苯乙烯，P：聚（2 -乙烯基吡啶），X，Y是可变参数），溶剂浇铸和退火薄膜用作样品。从两个系列中观察到几个具有正多边形的周期性阿基米德平铺结构（6.6.6）、（4.8.8）和（4.6.12）。对于后一个系列，观察到了稍微复杂一点的结构，(3.3.4.3.4))，此外，随着(3.3.4)样品的成分发生轻微变化，观察到由三角形和正方形组成的更复杂的平铺结构。 4.3.4）。尽管样品不具有周期性晶胞，但观察到了具有十二边形对称性的衍射图样，这是具有十二边形对称性准晶的证据。多边形的边长约为50nm，是硫族化物和树枝状分子系统的分级放大尺寸。