- ▸ Phosphorus-rich, char-forming intumescent flame retardant and intermediate
- ▸ Building block for halogen-free flame retardant systems in plastics and coatings
- ▸ Reactive component for fire-resistant textile and polymer finishes
A grade-specific Safety Data Sheet (SDS) — with the complete hazard classification, handling precautions, and transport information — is supplied with every shipment and available on request. Confirm all safety and regulatory details against the SDS for your specific grade.
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PEPA (a caged bicyclic phosphate) is a high-phosphorus char-forming flame retardant used in halogen-free and intumescent systems for polyolefins and engineering plastics. Its rigid cage structure makes it an efficient carbonization/char source. Identity: CAS 5301-78-0.
What it is
The caged bicyclic phosphate (CAS 5301-78-0, 2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-4-methanol 1-oxide, PEPA) is a high-melting solid with a high phosphorus content and a reactive hydroxymethyl group, so it can also be built into intumescent flame-retardant structures.
How it performs in fire
It acts in the condensed phase as a powerful char former, and its hydroxyl group lets it react into oligomeric/intumescent flame retardants. It is a building block for high-performance halogen-free FR systems.
Applications
PEPA is used as a char-forming component and intermediate in halogen-free and intumescent flame retardants for polyolefins (PP/PE) and engineering plastics, often with ammonium polyphosphate and a nitrogen source. See the flame retardants guide for intumescent systems.
Forms, grades and handling
PEPA is supplied as a high-melting white powder. Properties are typical reference values; the Certificate of Analysis (CoA) for the lot you buy governs. Handle per the current Safety Data Sheet (SDS), and confirm regulatory status and restrictions for your market and end use — flame-retardant regulation evolves. Each lot ships with CoA, TDS and SDS.
Bulk supply and RFQ
RawSource sources Caged Bicyclic Phosphate direct from producers in bulk, with CoA, TDS and SDS per lot. Tell us your polymer or system, the fire test you must pass, your maximum loading, and whether the application must be halogen-free, and we will quote the right grade. See the full range and selection logic in the flame retardants guide.
Typical Properties
Typical reference values, not a specification; the Certificate of Analysis (CoA) for the lot governs.
| Property | Typical Value |
|---|---|
| Chemical / class | Flame retardant / char former (caged bicyclic phosphate) |
| Flame-retardant type | Caged bicyclic phosphate (char former) |
| Role in fire performance | Condensed-phase char (high phosphorus) |
| CAS Number | 5301-78-0 |
| Molecular Formula | C5H9O5P |
| Molecular Weight | 180.10 g/mol |
| Handling | Refer to the current SDS |
Frequently Asked Questions
What is the caged bicyclic phosphate PEPA used for?
PEPA (CAS 5301-78-0) is a high-phosphorus caged bicyclic phosphate used as a char-forming flame retardant and intermediate in halogen-free and intumescent systems for polyolefins and engineering plastics; its hydroxyl group lets it react into intumescent FR structures.
How is bulk the caged bicyclic phosphate (PEPA) supplied and quoted?
RawSource supplies the caged bicyclic phosphate (PEPA) in bulk with CoA, TDS and SDS per lot. Pricing is quote-based on grade and volume; submit an RFQ with your target quantity, polymer/system and the fire test you must pass.