Specialty Additives Available — Bulk Only

Melamine Cyanurate

MCA
CAS 37640-57-6 · Formula C6H9N9O3 · MW 255.20 g/mol

A white crystalline powder and halogen-free flame retardant for unreinforced polyamides.

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CAS Number
37640-57-6
Formula
C6H9N9O3
Molecular Weight
255.20 g/mol
Material Family
Specialty Additives
At a Glance
Material Family
Specialty Additives
Record Type
Salt
Primary Role
Flame Retardancy · Lubrication
Functional Roles
Applications & Use Cases
  • Halogen-free flame retardant for glass-filled and unfilled nylon 6 and nylon 66, where it promotes char formation and dripping suppression to help reach UL 94 V-0/V-2 ratings in electrical connectors, switches, and housings.
  • Smoke- and corrosion-reducing alternative to halogenated flame retardants in thermoplastic compounds for electrical and electronic (E&E) components.
  • Anti-dripping and intumescent co-additive in polyolefin and intumescent coating systems, contributing nitrogen-source gas evolution during combustion.
  • Solid lubricant and friction-reducing additive in engineering-plastic compounds and certain metalworking/lubricant formulations owing to its layered crystal structure.
  • Flame-retardant filler in polyurethane foams and thermoset systems requiring a non-halogen, low-toxicity additive.
Physical Properties
Appearance
white crystalline powder
Molecular Weight
255.20 g/mol
Decomposition Temperature
>320 C (sublimes/decomposes)
Bulk Density
0.2-0.5 g/cm3 (typical, grade dependent)
Water Solubility
very low (~0.01 g/100 mL, sparingly soluble)
Physical Form
fine powder
Safety & Handling
Full SDS available on request

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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Chemical Identity
CAS Number
37640-57-6
Molecular Formula
C6H9N9O3
Molecular Weight
255.20 g/mol
IUPAC Name
1,3,5-triazinane-2,4,6-trione;1,3,5-triazine-2,4,6-triamine
PubChem CID
InChI Key
ZQKXQUJXLSSJCH-UHFFFAOYSA-N
Synonyms & Trade Names
Melamine isocyanurate Melamine cyanuric acid 1,3,5-Triazine-2,4,6(1H,3H,5H)-trione compound with 1,3,5-triazine-2,4,6-triamine (1:1) Melamine-cyanuric acid adduct 2,4,6-Triamino-s-triazine cyanurate Melaminecyanurate
Full Description

Melamine cyanurate (MCA) is the standard halogen-free flame retardant for unreinforced nylon — a nitrogen-based adduct of melamine and cyanuric acid that flame-retards polyamides and also acts as a lubricant additive. Identity: CAS 37640-57-6.

What it is

Melamine cyanurate (CAS 37640-57-6, C6H9N9O3) is a white crystalline powder, a 1:1 adduct of melamine and cyanuric acid. It is halogen-free and is the go-to flame retardant for unfilled/unreinforced polyamides.

How it performs in fire

It works mainly in the condensed and gas phases for nylon: it promotes dripping of the burning polymer away from the flame and releases inert gases that dilute it, achieving high flammability ratings in unreinforced PA at modest loading. (Glass-reinforced nylon, which cannot drip, instead uses phosphinate-based systems such as aluminum diethylphosphinate.) MCA also functions as a high-performance lubricant additive.

Applications

Melamine cyanurate is used as a flame retardant in unreinforced polyamide (PA6, PA66) fibers and moldings, and in some intumescent and coating systems, and as a lubricant additive. See nitrogen synergists in the flame retardants guide.

Forms, grades and handling

MCA is supplied as a fine white powder graded by particle size in bags and bulk. 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. Each lot ships with CoA, TDS and SDS.

Bulk supply and RFQ

RawSource sources Melamine Cyanurate 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 any particle-size or grade requirement, 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 (nitrogen-based, for nylon)
Flame-retardant type Nitrogen-based (halogen-free)
Role in fire performance Gas dilution + char; for nylon
CAS Number 37640-57-6
Molecular Formula C6H9N9O3
Molecular Weight 255.2 g/mol
Handling Refer to the current SDS

Regulatory & registration requirements

  • TSCA (US):
  • REACH (EU):
  • EC number: 253-575-7

TSCA Inventory flag PMN: a commenced PMN (premanufacture notice) substance (EPA flag legend).

Source: EPA TSCA Inventory (July 2025 release) · ECHA CHEM — retrieved 2026-07-12

Frequently Asked Questions

What is melamine cyanurate (MCA) used for?

Melamine cyanurate (MCA, CAS 37640-57-6) is the standard halogen-free flame retardant for unreinforced nylon (PA6, PA66), where it promotes dripping and releases inert gases to achieve high flammability ratings; it is also used as a lubricant additive.

Can melamine cyanurate be used in glass-reinforced nylon?

Generally no — MCA relies on the polymer dripping away from the flame, which glass-reinforced nylon resists, so reinforced grades typically use phosphinate-based flame retardants such as aluminum diethylphosphinate instead.

How is bulk melamine cyanurate supplied and quoted?

RawSource supplies melamine cyanurate in bulk with CoA, TDS and SDS per lot. Pricing is quote-based on grade, particle size and volume; submit an RFQ with your polymer/system and the fire test you must pass.

What is the REACH and TSCA regulatory status of Melamine Cyanurate?

Melamine Cyanurate (CAS 37640-57-6) is subject to U.S. TSCA Inventory requirements; supplying it into the EU requires valid REACH registration ((EC) No 1907/2006). RawSource cannot verify a third-party supplier's registrations — buyers should require documented TSCA and REACH compliance for their jurisdiction and volume (EC 253-575-7).

Disclaimer. Information on this page — including properties, identifiers, hazard, transport (DOT/UN) and tariff (HS) classifications, and applications — is provided for general reference and is compiled from authoritative public sources (e.g. PubChem/ECHA, 49 CFR 172.101, the Harmonized Tariff Schedule). Values are typical and are not a guaranteed specification; the Certificate of Analysis (CoA) for the lot purchased governs. Products are sold for industrial and professional use only. Nothing here is a medical, health, or efficacy claim or advice. Always consult the current Safety Data Sheet (SDS) before handling, storage, transport or disposal, and confirm regulatory status, classification and suitability for your application and jurisdiction. Hazard, transport and tariff classifications must be verified for your specific shipment. RawSource makes no warranty, express or implied, and assumes no liability for use of this information. Trademarks. Third-party trademarks and brand names are the property of their respective owners; any reference is nominative — used only to identify a comparable product — and does not imply affiliation with, sponsorship by, or endorsement by the trademark owner.