Rapid Synthesis of Dual-Responsive Hollow Capsules with Controllable Membrane Thickness by Surface-Initiated SET-LRP Polymerization

We present a facile and highly effective route to construct a dual-responsive polymeric capsule with photo-cross-linkable property based on surface-initiated single electron transfer living radical polymerization (SI-SET-LRP) exploiting silica particles as templates, dimethylaminoethyl methacrylate (DMAEMA) as dual-responsive component, and 2-hydroxy-4-(methacryloyloxy)benzophenone (BMA) as an effective photo-cross-linker. This approach is highly efficient with complete monomer conversion in 15 min at ambient temperature resulting in wall thickness of 55 nm and usable in technical applications. Hollow capsules are available after photo-cross-linking of polymeric shell and removing silica particle, of which the morphology and composition were confirmed by employing a range of techniques, such as FTIR, TGA, TEM, SEM, cryo-TEM, DLS, GPC, and UV–vis spectroscopy. Thus, it represents a significant advance in the development of complex polymeric capsules synthesis usable for various applications (e.g., biotechnology and systems biology).