PPG-51
AKA “Polypropylene Glycol-51, Humectant”
Synthetic
Ingredient Facts
PPG-51
AKA: Polypropylene Glycol-51, Humectant
Synthetic · Emollient · EWG: 4
Synthetic
Emollient
Skin Conditioner
Synthetic
Clean
A lightweight humectant that helps skin retain moisture, keeping it soft and smooth throughout the day.
CAS #
25322-69-4
Form
Liquid
See origin →
Functions
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Emollient
Fills in the tiny cracks between skin cells to make everything feel smooth and soft. The "silky finish" ingredient.
Viscosity Controlling
Locks in moisture
Traditional Use
A high-molecular-weight synthetic polypropylene glycol developed in the mid-20th century for use as a humectant and thickening agent in cosmetic formulations.
Skin Types
●all-skin-types
Best For
General
Melanin-Rich Skin
Suitable
Pregnancy & Breastfeeding Safe
Yes
Verified Feb 2026
Data: CosIng · EWG · CIR