Database/Viscosity Controlling/Polyurethane-39
Mostly petroleum · ISO 16128

Is Polyurethane-39 natural?

Mostly not. A PEG/diisocyanate polyurethane thickener; only the terminal fatty-alcohol portion of its Pareth end-caps is natural, diluted across a mostly petrochemical high-molecular-weight chain.

INCI namePolyurethane-39
FunctionViscosity Controlling
FeedstockMade by reacting petrochemical PEG-140 with hexamethylene diisocyanate…

How we scored it

PEG-140 backbone plus hexamethylene diisocyanate links, both fully petrochemical (~7500 Da), end-capped with Pareth surfactants whose fatty-alcohol portions (~500 Da total) are oleochemical → 500/8000 ≈ 0.06.
What counts. ISO 16128-2 scores the atoms that remain in the final ingredient. Reagents, solvents, catalysts and protecting groups used during manufacture leave no mass behind and are not counted.

Where it comes from

Made by reacting petrochemical PEG-140 with hexamethylene diisocyanate and end-capping the polymer with ethoxylated fatty-alcohol (Pareth) surfactants. The fatty-alcohol tails are oleochemical but a small fraction of this high-molecular-weight polymer.

In plain English

A synthetic thickening polymer used to control viscosity in liquid formulas. It's built mainly from petrochemical PEG and a synthetic isocyanate, with only a small natural fatty-alcohol portion at each chain end.

CosIng definition: Polyurethane-39 is a copolymer of PEG-140 and hexamethylene diisocyanate end-capped with C12-14 Pareth-10, C16-18 Pareth-11, and C18-20 Pareth-11

Natural alternatives with the same function

Agar 100% natural origin

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 Agarose 100% natural origin

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 Algin 100% natural origin

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 Alginic Acid 100% natural origin

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 Aluminum Behenate 100% natural origin

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 Aluminum Distearate 100% natural origin

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References

  1. 1ISO 16128-1:2016 and ISO 16128-2:2017 — Guidelines on technical definitions and criteria for natural and organic cosmetic ingredients and products. ISO, Geneva.
  2. 2POLYURETHANE-39. CosIng — European Commission cosmetic ingredient database. ec.europa.eu/cosing ↗
  3. 3POLYURETHANE-39. CosIng u2014 European Commission database for information on cosmetic substances and ingredients. https://ec.europa.eu/growth/tools-databases/cosing/search?search=POLYURETHANE-39