What Is Melamine?
Melamine, CAS 108-78-1, chemically 1,3,5-triazine-2,4,6-triamine, is a white crystalline, nitrogen-rich heterocyclic compound. It is the key raw material for melamine-formaldehyde (MF) resins and a building block for coatings, laminates and flame-retardant systems.
Melamine is a small, highly symmetrical molecule: a six-membered triazine ring bearing three amino (-NH2) groups. That structure gives it a very high nitrogen content (about 66% by weight) and makes it react readily with formaldehyde to form hard, heat-resistant thermoset resins. PolyBlueChem supplies melamine to a controlled specification (99.8% min purity) with per-batch COA and SDS, REACH-registered for Europe and with lower EU anti-dumping duty exposure.
| CAS number | 108-78-1 |
| Chemical name | 1,3,5-Triazine-2,4,6-triamine |
| Synonyms | Melamine; cyanuramide; 2,4,6-triamino-1,3,5-triazine; triaminotriazine |
| Molecular formula | C3H6N6 |
| Molecular weight | 126.12 g/mol |
| Appearance | White crystalline powder |
| Nitrogen content | About 66% by weight |
Chemistry and Structure
Melamine is a 1,3,5-triazine: a six-membered aromatic ring of three carbon and three nitrogen atoms, with an amino group on each carbon. This structure is the source of its properties:
- The symmetrical triazine ring is thermally and chemically robust, which is why MF resins are hard and heat-resistant.
- The three amino groups react with formaldehyde (and other agents), forming the crosslinked network of an MF resin. Three reactive sites make melamine highly functional.
- The high nitrogen content (~66%) makes melamine useful in nitrogen-bearing chemistry and, historically, it is also why it was misused as a nitrogen “filler” (see the safety note below).
Melamine is only slightly soluble in water and in common organic solvents; it dissolves in hot water and some polar solvents, and it sublimes/decomposes on strong heating rather than melting cleanly at ambient pressure. These properties shape how it is handled, stored and reacted.
How Melamine Is Produced
Commercial melamine is made almost entirely from urea. Under heat and pressure, urea is converted to melamine, releasing ammonia and carbon dioxide:
6 CO(NH2)2 -> C3H6N6 + 6 NH3 + 3 CO2
- Urea conversion – urea is heated (typically 350 – 400 °C) under pressure, with or without a catalyst, to form melamine.
- Quench and recovery – the product is cooled/quenched and the melamine is crystallised or purified from the reaction gases (ammonia and CO2 are recovered and recycled, often back to urea).
- Purification – the crude melamine is refined (for example by recrystallisation or by a gas-phase/quench process) to reach a high-purity, low-colour product.
Two main process families are used: high-pressure (HP) processes and low-pressure (LP, catalytic) processes. Both start from urea; they differ in pressure, catalysis and the recovery train, and both are aimed at a product with the low turbidity and colour values (or low oxygen content) that resin and coating makers require.
Specifications and Quality Control
Melamine is supplied as a white crystalline powder to the following specification:
| Parameter | Specification |
|---|---|
| Appearance | White crystalline powder |
| Purity | 99.8% min |
| Water | 0.1% max |
| pH | 7.5 – 9.5 |
| Ash | 0.03% max |
| Turbidity (Kaolin) | 20 max |
| Colour (Hazen, Pt-Co) | 20 max |
| Parameter | What it controls |
|---|---|
| Purity (99.8% min) | Assay; a high value means fewer by-products (for example ammeline/ammelide) that can affect resin colour |
| Water (0.1% max) | Moisture; affects weighing, caking and reaction consistency |
| pH (7.5 – 9.5) | Acidity/alkalinity of the aqueous extract; affects resin reaction |
| Ash (0.03% max) | Inorganic residues |
| Turbidity (Kaolin, 20 max) | Insoluble matter / clarity in solution |
| Colour (Hazen, 20 max) | Colour, which carries through to the resin and laminate |
The turbidity and colour limits are critical for resin and coating use: a melamine that is discoloured or turbid gives a cloudy or yellow resin. A specification sheet and a per-batch certificate of analysis (COA) are available on request.
Key Properties
| Property | Behaviour | Practical value |
|---|---|---|
| Form | White crystalline powder | Free-flowing; easy to handle and dissolve |
| Nitrogen content | About 66% | Highly functional; nitrogen-rich |
| Reactivity | Reacts with formaldehyde and other agents | Basis of MF thermoset resins |
| Solubility | Low in cold water; higher in hot water | Handling and reaction considerations |
| Thermal behaviour | Robust ring; sublimes/decomposes on strong heating | Heat-resistant resins; flame-retardant chemistry |
Applications
Melamine is used mainly as a raw material for thermoset resins and as a flame-retardant additive. The table maps the main uses.
| Industry / product | Function |
|---|---|
| Decorative laminates (HPL) | Melamine-formaldehyde resin for surface and overlay layers |
| Coatings | Amino (melamine) crosslinker for industrial and automotive coatings |
| Adhesives and binders | MF resin binder in wood panels and engineered wood |
| Moulding compounds | Hard, heat-resistant mouldings and tableware |
| Flame retardants | Melamine and melamine-based (e.g. melamine cyanurate) systems |
| Concrete admixtures | Sulfonated melamine-formaldehyde (SMF) superplasticiser |
| Paper and textiles | Wet-strength and finishing resins |
- Laminates and panels – the largest use; MF resins give hard, scratch- and heat-resistant surfaces for high-pressure laminates and engineered wood.
- Coatings – melamine acts as a crosslinker, reacting with hydroxyl- or carboxyl-functional resins to give durable, hard, chemical-resistant finishes.
- Flame retardants – melamine and its salts (notably melamine cyanurate) are used in halogen-free flame-retardant systems and intumescent coatings.
- Adhesives, paper and concrete – MF chemistry also serves wood adhesives, paper treatment and concrete superplasticisers.
Melamine-Formaldehyde Resin Chemistry
The dominant use of melamine is as the amine component of MF resins. The chemistry in brief:
- Methylolation – melamine reacts with formaldehyde to form methylolated melamine (a mixture of mono- to hexa-methylol species, depending on pH, temperature and ratio).
- Condensation / cure – on heating (and often with an acid catalyst), the methylol groups condense, forming methylene and ether bridges that create a rigid, crosslinked thermoset network.
- Property outcome – because melamine is trifunctional and the ring is robust, the cured resin is hard, heat-resistant, water-resistant and clear – ideal for laminates and coatings.
| Feature | Effect on the resin |
|---|---|
| Melamine functionality (3 amino groups) | High crosslink density; hard, tough resin |
| Triazine ring | Thermal and chemical resistance |
| Purity of the melamine | Colour and clarity of the resin/laminate |
The quality of the melamine (colour, turbidity, purity) therefore shows up directly in the colour and clarity of the finished laminate or coating, which is why the specification is tight on those values.
Melamine in Flame Retardants
Melamine is an important building block for halogen-free flame-retardant systems, because the nitrogen-rich ring releases inert gases and promotes charring when it decomposes under fire conditions (a physical, gas-phase and char-forming mode of action, not a flame-suppressing “additive” claim).
| Flame-retardant use | Role of melamine |
|---|---|
| Melamine (as such) | Nitrogen donor; endothermic decomposition; gas dilution |
| Melamine cyanurate | Additive for polyamides and other polymers |
| Intumescent systems | Blowing/char-forming component with an acid source and a carbon source |
| Polyurethane / other polymers | Nitrogen-based flame-retardant chemistry |
Because melamine chemistry is nitrogen-based, it fits the trend toward halogen-free flame retardants, where it is often combined with phosphorus-based (acid source) and carbon-source components in an intumescent system.
Melamine vs Other Amino and Triazine Raw Materials
Melamine is often compared with urea, dicyandiamide and other triazine/amino raw materials.
| Material | CAS | Functionality | Typical role |
|---|---|---|---|
| Melamine | 108-78-1 | Trifunctional triazine (3 amino) | Hard, heat-resistant MF resins; laminates; coatings; FR |
| Urea | 57-13-6 | Bifunctional | Lower-cost urea-formaldehyde resins; also the melamine feedstock |
| Dicyandiamide | 461-58-5 | Nitrogen-rich | Epoxy curing, flame retardants, intermediates |
| Benzoguanamine | 91-76-9 | Triazine with phenyl | Specialty amino resins with modified properties |
Guidance: melamine gives the hardest, most heat- and water-resistant amino resin; urea resins are cheaper but less durable; dicyandiamide serves different (epoxy curing, FR) roles; benzoguanamine modifies resin properties where needed.
Regulatory, REACH and Trade Notes
- REACH – our melamine is REACH-registered for the European market, supporting EU supply.
- EU anti-dumping – melamine is subject to EU anti-dumping measures; our supply is offered with lower anti-dumping duty exposure. Confirm the current rate and origin for your order, as rates and scope are subject to change.
- Not for food or feed – melamine is an industrial raw material and must not be used in food or feed. (Melamine is a controlled contaminant in food; it is strictly an industrial chemical.)
Safety, Handling and Storage
- Low acute hazard – melamine is a stable industrial solid, but dust should be controlled and good industrial hygiene practised.
- Dust – avoid breathing the powder; use local extraction where large amounts are handled; wear eye protection and gloves.
- Not for food/feed – keep segregated from food, feed and pharmaceutical materials; label clearly as industrial.
- Storage – keep sealed, cool and dry; melamine is stable but should be protected from moisture and contamination.
- Thermal – on strong heating melamine decomposes/sublimes and can release irritant nitrogen-containing vapours; avoid overheating.
Packaging, Logistics and Supply
| Item | Standard options |
|---|---|
| Packaging | 25 kg PP/PE bags; 1000 kg jumbo bags; palletised for containers |
| Documentation | Per-batch COA and SDS; REACH and trade documents on request |
| Incoterms | FOB and CIF |
| Storage | Sealed, cool and dry |
Melamine is a commodity resin raw material: price tracks the urea feedstock, energy and freight, and European delivered cost is strongly affected by anti-dumping duty. Buying on committed tonnage, and confirming the REACH and duty position, gives the best terms.
Melamine in Laminates and Engineered Wood
Decorative laminates and engineered-wood panels are the largest outlets for melamine, and they illustrate why its quality matters so much.
| Product | How melamine is used |
|---|---|
| High-pressure laminates (HPL) | Melamine-formaldehyde resin impregnates the decorative and overlay papers, then is pressed to a hard, clear surface |
| Low-pressure laminates / melamine boards | Melamine-impregnated paper pressed directly onto board |
| Engineered wood and panels | MF and MUF (melamine-urea-formaldehyde) adhesives for bonding |
| Overlays and films | Melamine resins for scratch- and heat-resistant surfaces |
In every case the melamine becomes part of a clear or translucent surface layer, so its colour (Hazen) and turbidity are visible in the finished product: a low-colour, low-turbidity melamine gives a bright, clear laminate, while impurities or colour carry straight through. That is why the specification is tight on these values, and why a resin maker will reject a batch that meets the assay but fails colour.
Melamine in Coatings: The Amino Crosslinker
In coatings, melamine (as a partially or fully alkylated melamine-formaldehyde resin) acts as the crosslinker for binder resins that carry hydroxyl or carboxyl groups – commonly polyester, acrylic and alkyd resins.
| Property | Contribution of the melamine crosslinker |
|---|---|
| Hardness | High crosslink density gives a hard, scratch-resistant film |
| Chemical resistance | Resistance to solvents, detergents and stains |
| Appearance | Clear, colour-stable films |
| Cure | Heat-cured (baking) systems with an acid catalyst |
Melamine crosslinkers are used in industrial, coil, automotive and appliance coatings, where a hard, durable, heat-cured finish is required. On cure, the melamine-formaldehyde crosslinker reacts with the binder to build the crosslinked network that gives the coating its performance.
Grade Selection and Quality for Melamine Buyers
Melamine is largely a single chemical, but grade and quality still matter.
| Consideration | Why it matters |
|---|---|
| Purity (99.8% min) | Fewer by-products; cleaner, brighter resin |
| Colour (Hazen) | Carries into the laminate, resin or coating |
| Turbidity | Clarity of the finished film or laminate |
| Water (0.1% max) | Consistent reaction and no caking |
| Particle size / form | Dissolution rate and handling |
For resin and coating makers, the practical grade question is colour and clarity: a high-purity, low-colour melamine is essential for bright laminates and clear coats, and the batch COA is the way to confirm it. For flame-retardant and non-appearance-critical uses, the colour requirement is less strict.
Frequently Asked Questions about Melamine
What is melamine used for?
Mainly as the raw material for melamine-formaldehyde (MF) resins used in laminates, coatings, adhesives and mouldings, and as a building block for flame retardants.
What is the CAS number of melamine?
108-78-1 (1,3,5-triazine-2,4,6-triamine).
Is melamine REACH-registered?
Our melamine is supplied REACH-registered for the European market.
Is melamine subject to EU anti-dumping duty?
Yes – melamine is subject to EU anti-dumping measures. Our supply is offered with lower duty exposure; confirm the current rate and origin per order.
Can melamine be used in food or feed?
No. Melamine is an industrial raw material and is not for food or feed use; it is a controlled contaminant in food.
Why do colour and turbidity matter?
Because they carry straight through into the resin, laminate or coating; a discoloured or turbid melamine gives a cloudy or yellow product.
How should melamine be stored?
Sealed, cool and dry, segregated from food, feed and pharmaceutical materials.
Related reading
- Melamine in melamine-formaldehyde resins, laminates and coatings
- Melamine in flame retardants and intumescent systems
- How to buy melamine: grade, REACH and EU anti-dumping
- Melamine (CAS 108-78-1) – product page
PolyBlueChem supplies melamine (CAS 108-78-1) to the specification above, REACH-registered with lower EU anti-dumping duty exposure, per-batch COA and SDS, and FOB/CIF delivery. Contact us with your application, tonnage and delivery port.