4-Phenylethynylphthalic anhydride (PEPA, CAS 119389-05-8) is a phthalic anhydride building block carrying a phenylethynyl group at the 4-position. It is widely employed to end-cap polyimides during their synthesis and modification, including TriA-X polyimides, for high-performance polymer and separation membrane research.
When heated, the diphenylacetylene end group undergoes radical curing, producing crosslinked polyimides with enhanced thermal stability, with a 5% decomposition temperature (Td5) of 591.3 °C reported. The same diphenylacetylene unit can also take part in a Diels-Alder reaction with tetraphenylcyclopentadienone to give fully conjugated hexaphenylbenzene.
PEPA can additionally be grafted as an imide pendant onto polymer backbones bearing free amine groups; membranes modified in this way show improved gas permeability for gas separation. The material is supplied as a pale yellow to yellow powder or crystal with purity above 98%.
- End-capping reagent in the synthesis and modification of polyimides such as TriA-X polyimides.
- Producing thermally crosslinked polyimides with improved thermal stability.
- Introducing imide pendant groups onto amine-bearing polymer backbones for gas separation membranes.
- Diels-Alder reactions with tetraphenylcyclopentadienone to form hexaphenylbenzene structures.
- Building block for high-performance polymer research.
| Brand | Ossila |
|---|---|
| CAS number | 119389-05-8 |
| Molecular formula | C16H8O3 |
| Purity | >98% |
| Category | — |
| Pack sizes | 10 g, 25 g, 50 g |
| Physical form | Pale yellow to yellow powder/crystal |
| Storage | — |
- Product code: B2151
- Full Name: 4-Phenylethynylphthalic anhydride
- Molecular Weight: 248.23 g/mol
- Synonyms: 5-(Phenylethynyl)isobenzofuran-1,3-dione, 5-(Phenylethynyl)-2-benzofuran-1,3-dione
- Classification / Family: Anhydride building block, Separation membranes, High-performance polymers
- Melting Point: Tm = 152 °C
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