Magnetic-patchy Janus colloid surfactants for reversible recovery of Pickering emulsions

We present a straightforward and robust method for the synthesis of Janus colloid surfactants with distinct amphiphilicity and magnetic responsiveness. To this end, hydroxyl-functionalized amphiphilic Janus microparticles are synthesized by seeded monomer swelling and subsequent photo-polymerization. By incorporating controlled amounts of hydroxyl groups on poly (styrene-co-vinyl alcohol) seed particles, we adjust the interfacial tension between the seed polymer and the poly (tetradecyl acrylate) secondary polymer (g13). From theoretical and experimental observations, we verify that when g13 is tuned to ~8.5 mN/m in a medium with controlled solvency, which corresponds to the 0.6 volume fraction of ethanol in water, the particles bicompartmentalize to form oval or ellipsoidal Janus microparticles with controllable bulb dimensions. We also show that bulb site-specific patching of magnetic nanoparticles can be achieved using the electrostatic interaction between the polyethylenimine-coated bulb surface and the polyvinylpyrrolidone-stabilized Fe2O3 nanoparticles. Finally, we demonstrate that our magnetic-patchy Janus microparticles can assemble at the oil-water interface, enabling magnetic-responsive reversible recovery of Pickering emulsions.??? ??????????????? ???????????? ?????????????????? ????????? ????????? ???????????? ?????????????????? ???????????? ???????????? ??????. ?????????????????? ?????? ????????? ????????? ???????????? ????????? Seeded swelling ????????? UV ???????????? ???????????? ???????????????. ?????? PS-co-PVA seed ??? PVA??? ?????? ????????? ?????? seed??? PTA ?????? ????????????(g13)??? ???????????????. ????????? ??? ????????? ????????? ??????, ????????? ?????? ?????? ???????????? volume fraction ??? 0.6????????? g13??? 8.5 mN/m ??? ??? ??? ?????? ????????? ????????? ????????? ???????????? ????????? ???????????? ????????? ?????? ??? ????????? ???????????????. ?????? ?????????, ????????? ????????? ????????? ????????? ????????? ?????? ????????? ????????? ????????? ????????? PEI??? ???????????? PEI??? PVP??? ???????????? ?????? ??????????????? ??????????????? ????????? ??? ?????? ?????? site??? ???????????????. ?????? ?????? ?????? ??????????????? ????????????????????? patching ??? ?????? ????????? ????????? ????????? ??? ?????????. ????????? ????????? ?????? ????????? ???????????? ????????? ????????? ????????? ????????? ????????? ?????? ???????????? ????????? ???????????? ????????? ??? ?????? ???????????? ???????????????. ?????????, ?????? ???????????? ?????????Pd ??????????????? patching ??? ????????? ????????? ?????? ????????? ????????? ?????? catalytic ?????? ????????? ?????????????????????, ????????? ??? ??????????????? ?????? ???????????? green chemistry??? ????????? ??? ?????????.Maste