Acrylic Acid/Stearyl Acrylate Copolymer
AKA “Acrylic polymer, Thickener
Acid
Ingredient Facts
Acrylic acid/stearyl acrylate copolymer
AKA: Acrylic polymer, Thickener
Acid · Emulsion Stabilising · EWG: 4
Plant-Derived
Occlusive
Emulsifier
Acid
Not Clean
2-Propenoic Acid, Polymer with Octadecyl 2-Propenoate
CAS #
36120-03-3
See origin →
Functions
Emulsion Stabilising
Forces oil and water to stay mixed instead of separating into layers. The unsung hero holding your lotion together.
Film Forming
Creates a physical seal on skin to lock moisture in and keep irritants out. The "slugging" ingredient — barrier protection.
Stabilizes Emulsion
Creates Protective Barrier
Fights Bacteria
Locks In Moisture
Creates protective layer
Keeps product blended
Traditional Use
A synthetic polymer created for cosmetic use to provide thickening and emulsifying properties. Used in cream and lotion formulations as an alternative to traditional natural thickeners.
Skin Types
all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
EWG
4
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
Not a Sensitizer
medical-approval
all-shades-safe
Regulatory Status
USApermitted
EUrestricted
JAPANrestricted
CANADArestricted
Verified Jun 2026
Data: CosIng · EWG · CIR