Large-Scale Synthesis of Reactive Janus Inorganic/Polymer Colloidal Dimer

A new method is proposed to large-scale synthesize reactive Janus inorganic/polymer colloidal dimers by electrostatics-mediated intramolecular crosslinking of the tethered diblock copolymer single-chain of PVSt-b-PmSt at an example inorganic NP of Fe3O4@SiO2. Tethering the single-chain is achieved by terminating the anionic living polymer onto the chloromethylphenyl- group capped NP. While the electrostatic interaction is introduced by complexation of the mercaptoacetic acid (MA) clicked PVSt block with 1-methylimidazole (MI), the intramolecular crosslinking is achieved with 1,6-hexanediisothiocyanate (HDI). The example dimer of cPVSt-b-PmSt-Fe3O4@SiO2 could be synthesized in a highly concentrated dispersion up to 100 mg/mL. The amphiphilic Janus colloidal dimer is effective to manipulate the stabilized emulsion droplets with a magnet. The parent colloidal dimer is highly reactive with residual chloromethylphenyl-, cyanate, and carboxylic acid groups at different sites to assist deriving a family of functional dimers by simple modifications.