In this study, we reported a kind of hollow poly(ionic
liquid)/α-Al2O3 composite particles prepared
by rapid microwave-assisted
Pickering emulsion polymerization using the commercial high hardness
α-Al2O3 abrasive (Mohs hardness = 9) as
a particulate surfactant. The structure and morphology were characterized
by different techniques. The as-prepared composite particles were
then used as the dispersed phase of the electrorheological polishing
fluid. Our results demonstrated that the hollow poly(ionic liquid)
core provided dispersion stability and electrorheological effect,
while the α-Al2O3 shell provided high
hardness and polishing capability. Under an electric voltage of 3
kV, the polishing fluid of the hollow poly(ionic liquid)/α-Al2O3 composite particles could improve the surface
quality of the stainless-steel workpiece with Mohs hardness of 5 from
Ra ∼270 to ∼90 nm. This polishing performance was extraordinary
and far better when compared to that of the polishing fluid consisting
of a simple mixture of poly(ionic liquid) particles and α-Al2O3 particles. During polishing, the voltage, rotation
speed, working gap, and polishing time were demonstrated to have an
effect on polishing efficiency. This study paves the way to develop
electrorheological polishing fluids with dispersion stability and
high polishing efficiency by combining hollow polymer particles and
high hardness of abrasives.