Database/Binding/Hydroxypropylcellulose
Mostly petroleum · ISO 16128

Is Hydroxypropylcellulose natural?

Mostly not. Cellulose backbone from wood or cotton pulp is natural; the heavily substituted hydroxypropyl groups from petrochemical propylene oxide dominate the final mass.

INCI nameHydroxypropylcellulose
CAS9004-64-2
FunctionBinding · Emulsifying Surfactant
FeedstockWood or cotton cellulose is etherified with petrochemical…

How we scored it

Cellulose AGU C6H10O5 162 Da (natural) + MS ~4 x hydroxypropyl (propylene oxide) 58 Da petrochemical addition -> 162/(162+232) = 162/394 = 0.41.
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.

How it’s made

Alkoxide opens propylene oxide (SN2), the new alkoxide opens a second one, protonation. Each curved arrow moves one electron pair, and the film ends on the score above.

Where it comes from

Wood or cotton cellulose is etherified with petrochemical propylene oxide to a high molar substitution (about 3.5-4.5) needed for water/organosolubility. No bio-based propylene oxide route is commercial.

In plain English

A film-forming thickener derived from plant cellulose, but so heavily modified with a synthetic group that most of its final weight is petrochemical rather than plant-derived.

CosIng definition: Cellulose, 2-hydroxypropyl ether

Natural alternatives with the same function

Agar 100% natural origin

A gelling and thickening gum extracted from red seaweed. It is used to give products body and texture,…

 Algin 100% natural origin

Sodium alginate, a thickening and binding gum extracted from brown seaweed. It's harvested from algae and processed to…

 Alginic Acid 100% natural origin

A gelling and thickening gum extracted from brown seaweed, the acid form of alginate. It's harvested and purified…

 Aluminum Zinc Oxide 100% natural origin

A white mineral powder made from zinc and aluminium oxides. It adds opacity, bulk and absorbency to powders…

 Amylopectin 100% natural origin

A binding and thickening ingredient that is the highly branched component of plant starch, typically sourced from corn,…

 Astragalus Gummifer Gum 100% natural origin

A natural plant gum, known as tragacanth, harvested from a Middle Eastern shrub. Used as a thickener and…

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. 2HYDROXYPROPYLCELLULOSE. CosIng — European Commission cosmetic ingredient database. ec.europa.eu/cosing ↗
  3. 3HYDROXYPROPYLCELLULOSE. CosIng u2014 European Commission database for information on cosmetic substances and ingredients. https://ec.europa.eu/growth/tools-databases/cosing/search?search=HYDROXYPROPYLCELLULOSE