alpha-methylstyrene

Alpha-methylstyrene (CAS 98-83-9), commonly abbreviated as AMS, is a reactive monomer and co-monomer used in polymer chemistry and specialty chemical manufacturing. Also known as isopropenyl benzene.

Where is alpha-methylstyrene used?

• Resin synthesis: building block and chain-transfer agent or modifier
• Coatings and adhesives: incorporated into styrene-acrylic and alkyd resin formulations to improve hardness, heat resistance and film build
• Packaging materials and printing inks: co-monomer in AMS-modified resins where controlled molecular weight is a production requirement
• Elastomer and sealant compounding: tackifiers and performance modifiers
• At trace levels it is approved as a flavoring agent under FEMA guidelines.

Good to know: Inhibited grades prevent premature polymerization during storage and transport. Not to be confused with isopropenyl benzene, a recognized alternative name in some technical contexts.

Commercial specifications

• Purity: 99% to 99.5%+ depending on end-use requirements
• Clear liquid in bulk, ISO tank and drum quantities