Hydrogenated Polyisobutene

Hydrogenated Polyisobutene molecular structure
molecular structure · PubChem
AKA: UCUGLVJQUIRCPK-UHFFFAOYSA-N
Synthetic
Emollient
Skin Conditioner
Clean
Propene, 2-methyl-, homopolymer
CAS #
40921-86-6, 61693-08-1
Form
Powder
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 synthetic polymer developed in the 20th century for the cosmetics industry. Created to provide long-lasting moisturization and improved texture without the rancidity problems associated with natural oils.
EWG
1
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-assessed2 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
Verified Jun 2026
Data: CosIng · EWG · CIR