Polysorbate 60 — Frequently Asked Questions

Its fatty chain is stearic acid, an eighteen-carbon fully saturated chain. Long saturated chains pack into an ordered arrangement and raise the melting point, so the material is a waxy semi-solid at room temperature, whereas Polysorbate 20 and 80 carry shorter or unsaturated chains and remain liquid. In practice this means Polysorbate 60 must be melted into the oil phase rather than simply stirred in cold.

Every oil phase has its own required HLB value, the balance of water-loving and oil-loving character needed to emulsify it stably. A single emulsifier gives one fixed HLB. Pairing high-HLB Polysorbate 60 with a low-HLB partner such as sorbitan stearate allows the blend ratio to be adjusted until it matches the oil phase, which gives a more stable emulsion than either component alone and is standard practice.

Not reliably. Its HLB of about 14.9 sits just below the threshold at which micelles become small enough to stop scattering light, so it tends to produce opaque or hazy systems rather than clear ones. If a transparent product is the objective, Polysorbate 20 or 80 is the appropriate choice. Polysorbate 60 is specified when a stable opaque cream or lotion with real body is what is wanted.

Both the oil and water phases are normally heated to around 70 to 75 degrees Celsius before combining, which ensures the Polysorbate 60 is fully melted and can distribute itself at the oil-water interface as the emulsion forms. Combining at too low a temperature leaves undissolved material that will not contribute to stability and may appear as specks in the finished product.