How to Disperse Powder in Oil

Dispersing powder in oil is often challenging because most powders are hydrophilic or lipophobic, making them difficult to disperse evenly in oil and prone to clumping or settling.

To achieve good and stable dispersion of powder in oil, the following methods are commonly used:

• Use a Dispersing Agent: This is the most crucial method. Dispersing agents help reduce the surface tension between the powder particles and the oil, allowing the particles to disperse uniformly in the oil. The choice of dispersing agent depends on the type of powder and oil being used.
• High-Speed Mixing: Using a high-shear mixer, such as a Homogenizer or high-speed stirrer, helps break down powder aggregates and disperse particles more finely in the oil.
• Add Powder Gradually: Add the powder to the oil little by little while continuously stirring or mixing to prevent clumping.
• Use Coated Powder: Some powders, like Zinc Oxide for sunscreens, may be surface-treated with substances compatible with oil, such as silicones, making them easier to disperse in oil.
• Use an Anti-Settling Additive: Certain additives, such as BYK 410, can help prevent dispersed powder particles from settling over time.

In the case of Zinc Oxide, which you previously inquired about, if you intend to use it directly in an oil-based formulation, choosing a Zinc Oxide product that is already supplied as a dispersion in an oil base is an easier and highly effective approach, such as:

• Zinc Oxide Transparent Dispersion (C12-15 alkyl benzoate Base): This is nano Zinc Oxide dispersed in C12-15 Alkyl Benzoate, a type of oil. It can be directly incorporated into the oil or silicone phase of your formulation.
• Zinc Oxide Transparent Dispersion (Isopropyl Palmitate Base): Similar to the above, but dispersed in Isopropyl Palmitate, another type of oil. It is also easy to use.

Powder forms of Zinc Oxide, such as Zinc Oxide (Micronized) or Zinc Oxide (Ultra-Fine, Non-Yellow, Non-Coated, USP), are often recommended for dispersion in water (with the help of high HLB emulsifiers) or for use in emulsion formulas rather than 100% oil formulas.

Therefore, if your formulation is oil-based, choosing a Zinc Oxide dispersion in an oil base or using an appropriate dispersing agent along with good mixing will help you effectively disperse the powder in oil.