Dose the liquid on amide activity. A kilo of 3EO liquid is not a kilo of flake.
Activity, not drum weight
Flake CMEA is mostly amide. A 3EO or 5EO liquid carries ethylene oxide units and sometimes water. Replacing flake one-for-one by weight under-doses the amide and the viscosity curve looks weak. Calculate activity first.
Esteem lists these EO grades for shampoos, baths, gels, and cleansing formulas, as foam boosters and viscosity builders in soaps and shampoos. That is the same job as flake CMEA, with a handling difference.
Process reasons to switch
Flakes need heat and shear in the anionic phase. A liquid can be metered. Plants that scorch flake on a tank wall and then call the amide dark should look at the liquid before they change the fatty acid.
The finished haze specification still applies. A liquid amide can be clear in the drum and cloudy in a cold-filled shampoo. Fill temperature belongs on the brief.
Choosing the mole ratio
Color of the amide shows up in a clear shampoo. Specify color if the base is uncolored.
Sulfate-free systems respond less to these amides. Read the sulfate-free note before you expect a SLES salt curve.
| Form | Why it is chosen | Dose rule |
|---|---|---|
| Flake CMEA | Highest amide per kilo | Dissolve hot |
| 3EO liquid | Pumpable, closer to flake | Dose on activity |
| 5EO liquid | Easier cold handling | Recheck foam feel |
| CDEA liquid | Different amide | Do not rename it CMEA |
What ethoxylation changes
Flake CMEA is the amide of coconut fatty acid and monoethanolamine. Adding 3 or 5 moles of ethylene oxide puts a short EO chain on that molecule and drops the melting point enough for a pumpable liquid. The hydrophobe is still the coco chain, so the job on the viscosity-builder table stays foam boost and viscosity in soaps and shampoos. The EO is a handling and solubility change, not a new detergent.
More EO makes the molecule more hydrophilic. Five moles usually stays clearer and more fluid in the cold than three moles, and it is a little less efficient per gram at packing the foam film, because more of each gram is EO rather than amide. Foam feel has to be rechecked. Mildness does not follow automatically from the extra EO. Irritancy is a test, not a mole-ratio claim.
Activity is the only fair comparison
Flake CMEA is mostly amide. A 3EO or 5EO liquid carries the oxide units and sometimes water. Replacing flake one-for-one by weight under-doses the amide. The salt curve looks weak and the plant concludes the liquid “does not build.” Calculate the amide activity and match that, then compare foam and viscosity.
The same correction runs in reverse. A formulator who doses the liquid at the flake percentage on a certificate that is already quoted as activity will overshoot, haze the shampoo, and move the salt peak. Write which basis the percentage uses before the trial is scaled.
Heat, color, and the cold fill
Flake needs heat and shear in the anionic phase. A liquid can be metered, which is why plants with no flake melter switch. The liquid can still darken if a drum heater scorches it, and that color shows in an uncolored shampoo. Specify color when the base has nowhere to hide it.
A liquid that is clear in a warm drum can still cloud the finished shampoo at the fill temperature, or thicken in a cold warehouse so a volumetric meter under-doses it. Cold stability of the raw material and clarity of the shampoo are two different tests. CDEA is a different amide and does not become CMEA because both arrive as liquids.
How to Specify with Esteem
- Say whether the plant can handle a hot flake or needs a pumpable liquid.
- Pick 3EO or 5EO and record activity.
- Match foam and viscosity against flake at equal amide activity.
- Check cold stability of the liquid.
- Do not claim the EO grade is the same melting point or the same DEA story as CDEA.
The note is on viscosity builders: liquid alternatives to regular CMEA for soaps and shampoos.