Vermicious thermo-responsive Pickering emulsifiers

摘要: Thermo-responsive vermicious (or worm-like) diblock copolymer nanoparticles prepared directly in n-dodecane via polymerisation-induced self-assembly (PISA) were used to stabilise water-in-oil Pickering emulsions. Mean droplet diameters could be tuned from 8 117 μm by varying the worm concentration and water volume fraction very high adsorption efficiencies (∼100%) obtained below a certain critical (∼0.50%). Heating dispersion up 150 °C led worm-to-sphere transition, which proved irreversible if conducted at sufficiently low concentration. This affords rare opportunity compare emulsifier performance of chemically identical worms spheres. It is found that former are markedly more efficient, since worm-stabilised droplets always smaller than equivalent sphere-stabilised under conditions. Moreover, latter emulsions appreciably flocculated, whereas stable. SAXS studies indicate mean thickness adsorbed layer surrounding comparable cross-section diameter determined for non-adsorbed dispersed continuous phase. Thus form monolayer shell around droplets, rather ill-defined multilayers. Under conditions, demulsification occurs on heating as result partial morphological transition.