murphyC30-45 Alkyldimethylsilyl Polypropylsilsesquioxane
molecular structure · PubChem
AKA: Silicone Resin
Synthetic
Occlusive
Not Clean
OriginSynthesized from alkyl silicones and polypropylsilsesquioxane polymers, belonging to the silicone chemical family. Produced through condensation polymerization of siloxane monomers with alkyl chains and propyl groups.
C30-45 Alkyldimethylsilyl Polypropylsilsesquioxane is a cosmetic ingredient used as film forming. Assessed as safe by the CIR.
CAS #
-
Form
Powder
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
Functions
Film Forming
Creates a physical seal on skin to lock moisture in and keep irritants out. The "slugging" ingredient — barrier protection.
Creates Protective Barrier
The paper trail
🔬Peer-reviewednone on file
⚖️Regulatory1 listing →
🛡️Safety-assessed1 review →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
EWG
4
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
Not a Sensitizer
1 study / 1 not sensitizing (CIR 743)
Concentration Guide
Leave-on0.2–4.9%
Rinse-offNot reported
0%50%100%
CIR reported use · 2016 survey
Regulatory Agencies
Verified Jun 2026
Data: CosIng · EWG · CIR