Key difference: Density of methanol ≈0.79 g/cm³; conventional dimethyl silicone oil (50‑1000 cSt) has a density of 0.96~0.97 g/cm³.
✅ No floating oil appears on the liquid surface; yet the oil phase will settle at the bottom of the container to form a bottom oil layer, which is totally different from the "floating‑oil" phenomenon in water.
1. Pure dimethyl silicone oil mixed with methanol (without any additives)
- High‑speed stirring / shaking: The liquid turns milky‑white and turbid. Silicone oil is broken into tiny oil droplets for dispersion; no floating oil can be seen on the liquid surface.
- Static placement after stirring: Silicone oil droplets gradually agglomerate, the oil phase settles at the bottle bottom, and the upper layer is clear methanol. The liquid surface stays clean, with a layer of transparent silicone oil at the bottom.
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Viscosity influence:
‑ Low viscosity (5‑20 cSt): Slow sedimentation, and the turbid state lasts longer.‑ High viscosity (350/500/1000 cSt): Rapid sedimentation and phase separation.
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