Caprolactam
The seven-membered cyclic amide supplied by Chelora Chemicals — the sole monomer for nylon 6 fibre and resin — exported from Indonesia as white prill or flake with full batch documentation on every shipment.
What Caprolactam is, and why buyers source it
A working overview of the compound's chemistry, its singular role as the nylon 6 monomer, and the grade Chelora Chemicals keeps in regular supply.
Caprolactam is a cyclic amide (lactam): a seven-membered ring formed by the internal condensation of 6-aminohexanoic acid, with the ring strain and amide functionality positioned so that the ring opens readily under ring-opening polymerisation conditions. That ring-opening reactivity is essentially the entire commercial story of the molecule — almost all caprolactam produced worldwide is converted into a single product family, nylon 6.
At room temperature it is a white, hygroscopic crystalline solid supplied as prill or flake, melting to a low-viscosity liquid a little above body temperature, which is why it is often handled and dosed molten in polymerisation plants. It is highly soluble in water and most polar organic solvents.
Where it fits in the value chain
Caprolactam's defining end use is ring-opening polymerisation to nylon 6 (polycaprolactam), used across textile and carpet fibre, engineering resin for automotive and electrical components, and film. Unlike nylon 66, which is built from two different difunctional monomers (hexamethylenediamine and adipic acid), nylon 6 is built from this single monomer alone, which opens and re-links with itself to form the polyamide chain. A smaller volume of caprolactam is also used as a chemical blocking agent for isocyanate groups in blocked-isocyanate powder coatings and adhesives, where it temporarily caps reactivity until deblocked by heat during cure.
Grade we supply
Chelora Chemicals offers Caprolactam in polymer grade (99.9%+ purity) as prill or flake, suited to nylon 6 fibre and resin polymerisation and blocked-isocyanate formulation. The grade is supplied with a batch-wise certificate of analysis.
How Caprolactam is made
An overview of the production route for orientation purposes. Our manufacturing partners' own process parameters and in-process controls are proprietary and are not disclosed beyond what is needed to interpret the certificate of analysis.
Caprolactam is manufactured predominantly from cyclohexanone via its oxime. Cyclohexanone (itself produced from cyclohexane oxidation or from phenol hydrogenation) is reacted with hydroxylamine to give cyclohexanone oxime, which then undergoes the Beckmann rearrangement: under strong acid catalysis (classically oleum/concentrated sulfuric acid, with newer vapour-phase processes using solid acid or zeolite catalysts), the oxime's carbon-nitrogen framework rearranges and ring-expands, inserting the nitrogen into the six-membered carbocyclic ring to give the seven-membered caprolactam ring.
In the classical liquid-phase Beckmann route, the rearrangement product is neutralised with ammonia, generating ammonium sulfate as a large-volume co-product (useful as a fertiliser but a significant waste-handling consideration), which is why newer vapour-phase Beckmann processes over solid acid catalysts, which avoid stoichiometric ammonium sulfate formation, have gained ground. The crude lactam is purified by extraction, hydrogenation of trace unsaturated impurities, and vacuum distillation to the polymer-grade specification required for fibre and resin-grade nylon 6.
Industries and processes that use it
Caprolactam is consumed almost entirely by nylon 6 fibre and resin manufacture, with a smaller, well-established secondary use as an isocyanate-blocking agent. The fields below account for most of the demand we see through our export desk.
Nylon 6 Textile & Carpet Fibre
Ring-opened and polymerised to nylon 6, spun into textile fibre for apparel, and bulked continuous filament for carpet manufacture.
Nylon 6 Engineering Resin
Polymerised to engineering-grade nylon 6 resin, injection-moulded into automotive, electrical and industrial components.
Nylon 6 Film & Packaging
Polymerised and extruded into biaxially oriented nylon (BOPA) film used in flexible food and industrial packaging.
Blocked-Isocyanate Powder Coatings
Used as a reversible blocking agent that caps isocyanate reactivity until released by heat during powder-coating and adhesive cure.
How the molecule is typically carried forward
The strained seven-membered lactam ring governs almost all of this molecule's further reaction chemistry. Reaction classes below account for most of the ways Caprolactam is converted into a finished polymer or formulation.
Hydrolytic Ring-Opening Polymerisation
Water initiates ring-opening at elevated temperature, and the resulting open-chain amino acid repeatedly condenses with itself, building the nylon 6 polymer chain.
Anionic (Fast) Polymerisation
A strong base catalyst opens the ring anionically, giving a much faster polymerisation used in reaction-injection moulding (RIM) and monomer-casting of large nylon 6 parts.
Reversible Isocyanate Blocking
The lactam nitrogen-hydrogen adds across an isocyanate group to form a blocked, temporarily unreactive adduct, which deblocks again (releasing free caprolactam) on heating during cure.
Hydrolysis to 6-Aminohexanoic Acid
Under aqueous conditions the ring can open fully to the open-chain amino acid, the same building block the lactam itself is formally the cyclic condensation product of.
Caprolactam against other polyamide and polyester intermediates we supply
Buyers sourcing caprolactam for nylon 6 manufacture often also need the nylon 66 monomer pair or the polyester-chain feedstocks. A quick reference to what else is on our regular supply list.
| Product | CAS Number | Category | Notes |
|---|---|---|---|
| Caprolactam | 105-60-2 | Cyclic lactam | The product on this page — the sole monomer for nylon 6. |
| Adipic Acid | 124-04-9 | Dicarboxylic acid | The co-monomer, with hexamethylenediamine, for nylon 66 — see its product page. |
| Hexamethylenediamine | 124-09-4 | Aliphatic diamine | The other nylon 66 co-monomer, supplied alongside adipic acid — see its product page. |
| Purified Terephthalic Acid | 100-21-0 | Dicarboxylic acid | The primary raw material for PET polyester, a related condensation-polymer chain — see its product page. |
Exact physical constants and purity specifications are confirmed per batch on the certificate of analysis — treat the notes above as a sourcing guide, not a specification sheet, for products other than Caprolactam.
Safety classification at a glance
Based on GHS classification as commonly listed for this substance. This is a summary for orientation only — always work from the current safety data sheet supplied with your specific batch.
Harmful if swallowed.
Causes skin irritation.
Causes serious eye irritation.
May cause respiratory irritation.
Chemical-resistant gloves, safety goggles and dust-suitable respiratory protection are the baseline for routine handling.
Handled as prill or flake; minimise airborne dust during transfer and packing.
Handled molten above its melting point in some dosing systems; standard hot-material handling precautions apply.
Warning — GHS07 harmful pictogram applies.
This compound is harmful if swallowed, causes skin and eye irritation, and may cause respiratory irritation, particularly when handled as fine dust. It should be handled with chemical-resistant gloves, eye protection and dust control, particularly during milling and packing, and with standard hot-material precautions where handled molten. Full first-aid, storage, spill and PPE guidance is in the MSDS issued with every shipment, and should be read in full before this material is handled.
Keeping it on spec between delivery and use
General storage guidance for this grade. Site-specific storage rules, segregation requirements and re-test intervals should follow your own EHS procedures and the MSDS issued with your batch.
Store in a cool, dry area away from strong oxidising agents and strong acids, in tightly closed original packaging, protected from moisture. If handled molten, maintain even heating to avoid localised degradation and colour development. If a batch is held past its retest date, re-check assay, colour and melting point before use.
How it ships from Indonesia
Standard packing and export terms for this product. Confirm exact figures against your order — they vary slightly by destination and quantity.
What travels with every batch
Specification is agreed before the purchase order, not discovered on arrival. Every shipment of Caprolactam leaves with a documented, checkable paper trail.
Certificate of Analysis
Batch-wise assay, colour and key physical constants, issued against the agreed specification so your QC team can check it, not just file it.
Safety Data Sheet
GHS-format SDS in English covering hazard classification, handling, storage, first-aid and spill response for the exact grade shipped.
Technical Data Sheet
Reference physical and chemical properties, recommended storage and typical applications, for internal circulation to your process or R&D teams.
Certificate of Origin
Confirms Indonesian origin for customs clearance and any preferential-duty claim at your destination port.
Dangerous Goods Declaration
UN packing group, classification and shipper's declaration prepared ahead of loading so documentation never holds up customs.
Third-Party Inspection
Independent pre-shipment inspection and re-sampling can be arranged on request, at your cost, for buyers who require it as a matter of policy.
Frequently asked questions
What buyers most often ask our sales desk about this grade.
01What is Caprolactam used for?+
02What is the CAS number of Caprolactam?+
03How is Caprolactam made?+
04What purity grade does Chelora Chemicals supply?+
05Is Caprolactam hazardous?+
06Why does nylon 6 need only one monomer when nylon 66 needs two?+
07What packing options are available?+
08How long does delivery take?+
09Can I get a sample before placing a bulk order?+
10Do you supply the nylon 66 monomers as well?+
Need Caprolactam on spec, on time?
Send us your required purity, quantity, packing preference and destination port. Our desk quotes most enquiries within one working day.