Dynamic Colloidal Photonic Crystal Hydrogels with Self-Recovery and Injectability
(a) Synthesis of the PBA-microgels. (b) Dynamic crosslinking of the preassembled PBA-microgel colloidal crystals via photoinitiated polymerization of cis-diol-containing glycomonomers. (c) Dynamic light scattering (DLS) analysis of the PBA-microgels. Inserts: SEM images showing the morphology of the dry PBA-microgels (average diameters of the PBA-microgels in corresponding SEM images from left to right were 130, 160, and 190 nm). . (d) FT-IR spectra of the PBA-microgels and PC hydrogels. The reaction between PBA and cis-diol groups in GMAPMA resulted in a weakened peak of B-O stretching (1366.8 cm-1). (e) Reflection spectra and the corresponding photos of three typical colloidal PC hydrogels. (f) The linear relation between the diameter of PBA-microgels and photonic stopband of the corresponding colloidal PC hydrogels. The reflection peak (λ) of PC materials can be estimated by Bragg’s equation, , in which d111 is the interplanar distance of (111) diffracting planes and naverage is the average refractive index of the materials. (g) Photos of the three PC hydrogels. Hydrogel sizes: .. (h) SEM images of the lyophilized hydrogels with short-range order in the assembled microgels. Scale bar is 500 nm.