Abstract
A mesoscopic tiling pattern with 12-fold symmetry has been observed in a three-component polymer system composed of polyisoprene, polystyrene, and poly(2-vinylpyridine) which forms a star-shaped terpolymer, and a polystyrene homopolymer blend. Transmission electron microscopy images reveal a nonperiodic tiling pattern covered with equilateral triangles and squares, their triangle/square number ratio of 2.3 (), and a microbeam x-ray diffraction pattern shows dodecagonal symmetry. The same kind of quasicrystalline structures have been found for metal alloys (), chalcogenides (), and liquid crystals (). The present result () confirms the universal nature of dodecagonal quasicrystals over several hierarchical length scales.
- Received 10 January 2007
DOI:https://doi.org/10.1103/PhysRevLett.98.195502
©2007 American Physical Society