Styrene/Methylstyrene Copolymer

AKA: Styrene-Methylstyrene Copolymer
Synthetic
Not Clean
OriginDerived from styrene and methylstyrene monomers, both petroleum-based hydrocarbons from the aromatic chemical family. Synthesized through free radical polymerization, where monomers are chemically linked to form long polymer chains.
Ethenyl-benzene and (1-methyl-ethenyl) benzene copolymer
CAS #
9011-11-4, 37218-15-8
Form
Liquid
State
Solid
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Caution
Functions
Binding
Depilatory
Holds Formula Together
Removes unwanted hair
Holds ingredients together
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
Caution
Concentration Guide
CIR lists it as not reported to be in use.
CIR · report published 2014
Regulatory Status
USA✔ permitted
EU⚠ restricted
JAPAN⚠ restricted
CANADA⚠ restricted
Verified Jun 2026
Data: CosIng · EWG · CIR