Butene/Propylene Copolymer

Butene/Propylene Copolymer 1
AKA: Olefin Copolymer
Synthetic
Occlusive
Not Clean
Butene/Propylene Copolymer is a copolymer of butene and propylene monomers.
CAS #
29160-13-2
Form
Liquid
State
Solid
Functions
Film Forming
Creates a physical seal on skin to lock moisture in and keep irritants out. The "slugging" ingredient — barrier protection.
Viscosity Controlling
Creates Protective Barrier
Controls Viscosity
Creates protective layer
Controls product thickness
Traditional Use
A synthetic polymer developed in the 20th century for use in cosmetic formulations as a film-former and conditioning agent. It has no natural or traditional predecessor.
EWG
4
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
Not a Sensitizer
medical-approval
all-shades-safe
Regulatory Status
USA✔ permitted
EU⚠ restricted
JAPAN⚠ restricted
CANADA⚠ restricted
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory1 listing →
🛡️Safety-assessed1 review →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
Verified Jun 2026
Data: CosIng · EWG · CIR