Styrene monomer is often characterised by the ASTM D2827-95 specification which establishes the following requirements:
| Property | Specification | ASTM Test Method |
|---|---|---|
| Purity, weight %, min | 99.7 | ASTM D 5135 |
| Aldehydes, weight %, max as benzaldehyde | 0.02 | ASTM D 2119 |
| Peroxides, mg/kg, max as H2O2 | 100 | ASTM D 2340 |
| Polymer, mg/kg, max | 10 | ASTM D 2121 |
| Inhibitor, mg/kg | 10 to 15 (or as required) | ASTM D 4590 |
| Colour, Pt/Co scale, max | 10 | ASTM D 1209 |
Styrene monomer is inhibited with para-tertiary-butylcatechol, abbreviated as p-TBC. Special quality requirements can be made upon agreement.
