Figure 3: Characterization of superstructure formed in patterned hydrogels.

Observation of superstructure of PBDT in patterned PDMAPAA-Q hydrogels at as-prepared (a,b) and swollen (c,d) states. The gels were observed under POM from top (a,c) and side (b,d) directions. The thickness of the observation direction from side was unified into ~2 mm. The images in column (i) were observed under the parallel polarizers, columns (ii) and (iii) were observed under the crossed polarizers without and with 530-nm tint plate, respectively. The column (iv) is a schematic illustration of the orientation of PBDT molecules within the gel, where the green bars represent PBDTs with weak orientation, the green circles represent PBDTs orientation of vertical direction to the sheet, the orange and blue bars represent highly ordered PBDTs. A: Analyzer; P: Polarizer; X′: fast axis of the tint plate; Z′: slow axis of the tint plate. Scale bar, 1 mm.