Glyceryl Stearate (and) PEG-100 Stearate

This emulsifier is manufactured by a lot of different companies, so it ends up having a lot of different names, including (but not limited to):

• Arlacel™ 165 (Croda)
• Radia 7490 (Oleon)
• Glyceryl Stearate (and) PEG-100 Stearate (Solvay Novecare)
• CreamMaker Blend (MakingCosmetics)
• HallStar® GMS SE/AS (Hallstar)
• Lexemul® 561 MB (INOLEX)
• Lonzest™ MSA Glyceryl Stearate (Lonza)
• SIMULSOL™ 165 (SEPPIC)
• TEGO® Care 165 (Evonik Operations GmbH)
• iEmul 165 (Polybase 165) (Cosphatech LLC)
• LotionPro 165 (Lotion Crafter)

Because there are so many different manufacturers of this blend of ingredients it’s important you get specific information for the ingredient you’re using from your supplier as there may be variations between products.

I typically use Glyceryl Stearate (and) PEG-100 Stearate at 9–14% of the oil phase.

Unlike emulsifying waxes like Polawax, Emulsifying Wax NF, Olivem 1000, and Ritamulse SCG, Glyceryl Stearate (and) PEG-100 Stearate does not substantially thicken emulsions, even in emulsions with very large oil phases. It is also substantially more stable in very thin emulsions.

For example, let’s imagine we have four different emulsions; 2 emulsified with Polawax, and 2 emulsified with Glyceryl Stearate (and) PEG-100 Stearate. One of each emulsifier has a 15% oil phase, and the other two have a 30% oil phase—the only ingredients in the oil phase are a liquid oil and the emulsifier. There are no added thickeners, like gums or fatty alcohols (cetyl alcohol, cetearyl alcohol, etc.)

The Polawax emulsions will have drastically different viscosities. The 15% one will be fairly thin, but still lotion-y. It would work well in a pump-top bottle, or possibly even a bottle with a treatment pump cap. The 30% one will be more like a cream; thick and rich, and much better suited to a jar or tub.

The Glyceryl Stearate (and) PEG-100 Stearate emulsions will have very similar viscosities. The 15% one will be about the consistency of partly skimmed milk, while the 30% one will be more like cream. The 30% one is more viscous because the inner phase (the oil phase) is larger, but that viscosity difference is pretty small—especially when compared to differing phase sizes in an emulsion made with Polawax. Both Glyceryl Stearate (and) PEG-100 Stearate emulsions could be packaged in a spray bottle, and are far too thin for any sort of pump bottle or jar.

Because Glyceryl Stearate (and) PEG-100 Stearate does not thicken emulsions, it gives us the ability to control the viscosity and oil phase size independently. For instance, you can create an emulsion with a 50% oil phase and decide if you want it to be a thinner, pumpable lotion or a thick, solid cream. You can also choose what you want to thicken it with, allowing you significantly more control over the skin feel of the finished product. With an emulsifying wax like Polawax, that product could only be solid, and the skin feel will be harder to adjust given the unavoidable presence of the thickeners in Polawax.

Additionally, because Glyceryl Stearate (and) PEG-100 Stearate doesn’t add viscosity to our emulsions, it has the ability to create far lighter feeling emulsions—in that way, it’s almost ‘invisible’ in your formulations. If you want to add the fluffy creaminess and weight of cetearyl alcohol, you’ll have to add it yourself—if you used Emulsifying Wax NF instead, that already contains 65–80% cetearyl alcohol, so you can’t avoid it.

Glyceryl Stearate (and) PEG-100 Stearate also works at lower rates than more common emulsifying waxes. Compared to Emulsifying Wax NF, Glyceryl Stearate (and) PEG-100 Stearate contains a higher percentage of the emulsifying ingredient. Emulsifying Wax NF contains 20–35% Polysorbate 60, while Glyceryl Stearate (and) PEG-100 Stearate contains approximately 50% PEG-100 Stearate. I’ve seen (and successfully used) Glyceryl Stearate (and) PEG-100 Stearate at 9–17% of the oil phase, compared to 20–25% for emulsifying waxes like Polawax, Emulsifying Wax NF, Olivem 1000, and Ritamulse SCG.

A thickening emulsifying wax like Emulsifying Wax NF or Olivem 1000 can work in some situations, though you will need roughly twice as much. Because these emulsifying waxes contribute fatty thickening to finished products, formulations designed to work with Glyceryl Stearate (and) PEG-100 Stearate will likely be significantly more viscous if you use a thickening emulsifying wax in its place. Depending on the formulation you may be able to adequately compensate by removing any additional fatty thickeners, but this will take some experimenting to get right.

The Body Shop uses Glyceryl Stearate (and) PEG-100 Stearate to emulsify their signature body butters!