The one flame retardant that fights fire with dripping. In unfilled nylon, 8–12% MC earns UL94 V-0 — a loading so low the mechanicals barely notice. Halogen-free, antimony-free, white, and gentle enough that even POM tolerates it. Supplied as fine powder and pre-blended packages.
Fig. MC01 — MC powder at incoming QCFine white melamine cyanurate powder before compounding.
Take melamine, pair it 1:1 with cyanuric acid, and the two lock into a salt-like adduct held together by hydrogen bonds. The result: a nitrogen store that stays put through 320 °C processing, then dumps inert gas exactly when a flame needs suffocating. No halogens, no phosphorus, no acid — which is why it fits resins other flame retardants would attack.
PA6 and PA66 without glass are MC’s home turf. V-0 at 8–12% — brominated needs more, minerals need five times more. Cable ties, connectors, housings.
In TPU, MC partners with DEPAL — the nitrogen half of the 18–22% package that keeps EV cable jackets both V-0 and flexible.
POM depolymerizes under acid — halogens and most phosphorus systems are off-limits. MC is acid-free and even scavenges the formaldehyde POM sheds.
Every other flame retardant fights dripping. MC recruits it. UL94 V-0 forbids flaming drips — not drips. MC exploits that one word.
Decomposition above ~320 °C is endothermic — energy leaves the flame zone just to break MC apart.
Released melamine and its breakdown gases are inert. They dilute oxygen and fuel vapors at the surface — drips detach before they can ignite, and stay out.
In molten PA, MC drops melt viscosity so burning material sheds fast — the flame literally falls off the part. This is why glass fiber, which anchors the melt, breaks the mechanism.
Match the row to your part before asking for pricing — the glass-fiber line changes everything.
| Application | MC Role | Typical Loading | Realistic Result | Related Page |
|---|---|---|---|---|
| Unfilled PA6 / PA66 (ties, housings) | Solo flame retardant | 8–12% | UL94 V-0, colors clean, mechanicals kept | FR nylon 66 guide |
| Glass-filled PA66 / PBT | N-synergist only — not solo | 5–10% beside DEPAL | V-0 via the phosphinate; MC alone fails on GF | DEPAL page |
| TPU cable jackets | Nitrogen half of P-N package | Part of 18–22% total | V-0 / VW-1 with flexibility kept | FR TPU guide |
| POM / acetal parts | The tolerated FR | 10–20% | V-2 class; also binds formaldehyde | FR POM guide |
| Epoxy, adhesives, thermosets | Co-flame-retardant | System-dependent | Halogen-free formulations | — |
One question decides it: is there glass in the part?
No glass, no problem: the drip mechanism works and the economics are unbeatable.
Fibers anchor the melt; the drip trick dies; the phosphinate takes over.
Particle size is the quiet variable: coarse MC weakens weld lines and shows in thin walls; fine grades cost more and disperse better. The rest is your part talking.
Fine-particle MC powder, plus the blends it belongs in: MC/DEPAL packages for TPU and glass-filled work, MC-based recipes for unfilled PA and POM. Every ladder burns in our own UL94 chamber before we quote it.
Fig. MC02 — burn verification in our labDrip behavior is judged live, not from a datasheet.
Fig. MC03 — export packagingBags, big bags and palletized supply for overseas buyers.The four questions that come up in almost every MC inquiry.
A 1:1 adduct of melamine and cyanuric acid — a halogen-free nitrogen flame retardant, stable to ~320 °C, that cools and dilutes flames with inert gas. Its signature result: UL94 V-0 in unfilled nylon at just 8–12% loading.
Because it recruits dripping instead of fighting it. MC thins the burning melt so drips shed fast and carry the flame off the part, while the nitrogen release keeps those drips from staying lit. V-0 permits non-flaming drips — MC lives in that clause.
Not as the main flame retardant — glass anchors the melt and kills the drip mechanism. Glass-filled PA and PBT run DEPAL-based systems, with MC or MPP in the supporting nitrogen role. Same molecule, different job.
It is the least-bad and usually the right one. POM unzips under acid attack, disqualifying halogens and most phosphorus chemistry; acid-free MC is tolerated and also scavenges formaldehyde. Expect V-2 class — if the spec says V-0 at thin wall, the honest answer is a resin change.
Two facts decide most MC quotes: filled or unfilled, and the UL94 class at your wall. Send those plus color and volume — we burn the ladder and reply with the grade, the loading and the proof.