Figure 19.

(a) Schematic of the electric field driven swelling of a silica-PFS PhC composite. (b) Optical responses of the PS-b-QP2VP photonic gel film (left) depending on UV irradiation dose and multicolor patterns created using a photomask having gradient pattern density to control local crosslink density (right). Reproduced with permission.³²⁸ (c) Schematic of writing and erasing of opal photonic paper by UV induced ring-opening and temperature induced ring-closing reaction of RhBMA dye 3 (top) and optical images of a patterned elastomeric opal film after activation of RhBMA-labeled beads (right) and temperature-induced reversible erasing (left). Reproduced with permission.³¹⁷ Copyright 2013, American Chemical Society.