Improved Electrorheological Polishing Property of Poly(Ionic Liquid)/Al₂O₃ Composite Particles Prepared via Pickering Emulsion Polymerization

Electrorheological (ER) polishing is an electric field-assisted polishing technology, but its application is limited by the insufficient performance of ER polishing fluids. This insufficient performance is mainly because the present ER polishing fluids are prepared by simply mixing abrasive particles into ER fluids, and the phase separation is easy to occur under simultaneous action of the electric field and shear field due to the difference in the ER effect between ER particles and abrasive particles. To solve this problem, we here reported a kind of composite ER polishing particles composed of poly(ionic liquid) (PIL) ER active particles covalently attached with commercial Al2O3 nanoabrasives. The composite particles could be facilely prepared by the polymerization of a Pickering emulsion with vinyl ionic liquid as the oil phase and silane-modified Al2O3 nanoparticle abrasives as the solid surfactant. Under simultaneous action of the electric field and shear field, the PIL/Al2O3 composite particles well overcome the phase separation problem of abrasive and ER active particles and exhibit a significantly better ER effect and polishing property compared to the simple mixture of the Al2O3 abrasive and PIL ER particles. This paper provides a way to solve the phase separation problem of traditional ER polishing fluids by integrating the ER effect and polishing property into a particle system.