Effect of Surfactant HLB Value on Settlement Stability of Magnetorheological Fluid

The hydrophilic-hydrophobic balance (HLB) of surfactants has a great influence on surfactants. Among them, polyethylene glycol has an HLB value of 20 and is highly hydrophilic; oleic acid has an HLB value of 1, which is very lipophilic; and sodium dodecylbenzenesulfonate has an HLB value of 10.6 between the two. This paper explores the use of these three surfactants with typical HLB values to improve the performance of magnetorheological fluids, mainly to study its effect on the stability of magnetorheological fluids. Tests have shown that the use of lipophilic surfactants in oil-based magnetorheological fluids has better sedimentation stability than the use of hydrophilic surfactants.