Low-Density Polyethylene CAS 9002-88-4
Chelora Chemicals supplies film, extrusion coating and injection grades of low-density polyethylene to converters and compounders worldwide. Every consignment leaves with a batch-specific COA covering melt flow index, density, additive package and volatiles, the current SDS and full export documentation.
Also known as: LDPE · Low density PE · High pressure polyethylene · PE-LD · Polythene
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Price, lead time and a sample COA for Low-Density Polyethylene, usually within one working day. We ship worldwide.
Request a Quote Email the DeskDocumentation
- Batch-specific COA (MFI, density, additive package)
- Safety Data Sheet (SDS)
- Transport and export documents
- Third-party inspection on request
- Certificate of origin
What is Low-Density Polyethylene?
Low-density polyethylene is the original polyethylene, made at very high pressure by free radical polymerisation of ethylene. The process produces long chain branches that prevent close packing, giving a density of 0.915 to 0.935 g/cm³.
Those long branches are what distinguish LDPE commercially. They give melt strength, clarity and processability that linear grades cannot match, which is why LDPE survives alongside cheaper LLDPE.
Film is the dominant application: shrink film, liquid packaging, lamination film and agricultural film. Extrusion coating, wire insulation, injection moulding and blow moulding take the rest.
LDPE is chemically inert, food-contact approved in the right grades, and entirely non-hazardous in handling. The practical issues are dust, pellet containment and correct grade selection.
Why LDPE specifically
- Long chain branching. Gives high melt strength for bubble stability in blown film and for extrusion coating.
- Optical clarity. Better than LLDPE or HDPE at the same thickness, which matters in packaging film.
- Easy processing. Runs at lower pressures and motor loads than linear grades on the same equipment.
- Excellent sealing. Low seal initiation temperature and broad sealing window for packaging.
How Low-Density Polyethylene is Manufactured
LDPE is made by free radical polymerisation of ethylene at extremely high pressure, in autoclave or tubular reactors.
- Ethylene compression. Polymer-grade ethylene is compressed to 1500 to 3000 bar, among the highest pressures in industrial practice.
- Initiator injection. Organic peroxides or oxygen initiate free radical polymerisation at 150 to 300 °C.
- Autoclave or tubular reactor. Autoclaves give more long chain branching and higher melt strength; tubular reactors give narrower distribution and better optics.
- Chain transfer control. A chain transfer agent sets the melt flow index.
- Separation and recycle. Unreacted ethylene is separated in high and low pressure separators and recycled.
- Extrusion and pelletising. The polymer is compounded with antioxidant, slip and antiblock additives as required, then pelletised.
Typical Commercial Specification
Figures below are representative of a general-purpose film grade LDPE. Each grade has its own data sheet — tell us the application and we will send the matching one.
| Parameter | Typical Value |
|---|---|
| Appearance | Translucent cylindrical or lenticular pellets, free of contamination |
| Melt flow index (190 °C / 2.16 kg) | 0.3 – 70 g/10 min depending on grade |
| Density | 0.915 – 0.935 g/cm³ |
| Volatiles | 0.05% max |
| Additive package | Antioxidant, slip and antiblock to grade |
| Tensile strength at break | Typically 10 – 25 MPa |
| Elongation at break | Typically 300 – 700% |
| Vicat softening point | Typically 85 – 100 °C |
| Ash content | To grade, typically 0.02% max |
Physical & Chemical Properties
| Property | Value |
|---|---|
| Chemical formula | (C₂H₄)ₙ |
| Appearance | Translucent to opaque white pellets |
| Density | 0.915 – 0.935 g/cm³ |
| Melting range | About 105 to 115 °C |
| Crystallinity | Typically 45 to 55% |
| Water absorption | Negligible, under 0.01% |
| Chemical resistance | Excellent to acids, alkalis and salts; swollen by hydrocarbons |
| Dielectric strength | Excellent, which is why it is used in cable insulation |
| Processing temperature | Typically 160 to 220 °C |
| Thermal stability | Degrades above about 300 °C, releasing hydrocarbons |
| Incompatibilities | Strong oxidisers; swelling by aromatic and chlorinated solvents |
Behaviour in the process
LDPE is a forgiving polymer to process, with a few characteristic behaviours:
- High melt strength. The bubble is stable in blown film and the melt curtain holds in extrusion coating, both consequences of long chain branching.
- Low seal initiation. Seals at lower temperature than linear grades, widening the sealing window.
- Environmental stress cracking. Lower resistance than HDPE; relevant where containers hold surfactants or oils.
- Moisture-free but dusty. Does not need drying, but pellet fines and angel hair accumulate in conveying lines.
LDPE Grades and Alternative Polyethylenes
Polyethylene is bought by grade, and the three families serve different needs even where the applications overlap.
| Material | Origin / type | When it is the right choice |
|---|---|---|
| LDPE | High pressure, long chain branched | Film clarity, melt strength, extrusion coating and sealing layers |
| LLDPE | CAS 25087-34-7, linear with short branches | Film strength, puncture and tear resistance; often blended with LDPE |
| HDPE | CAS 9002-88-4, linear | Rigidity, barrier and stress crack resistance for bottles and pipe |
| EVA | Ethylene-vinyl acetate copolymer | Where more flexibility, adhesion or lower seal temperature is needed |
| Metallocene LLDPE | Narrow distribution linear | Thin gauge film with high strength, at a premium |
Stated plainly: most film producers blend LDPE with LLDPE rather than choosing between them, because the blend gives both processability and strength. Pure LDPE remains the right choice for extrusion coating and for clarity-critical film.
Industries We Supply Low-Density Polyethylene To
LDPE goes to packaging converters, agriculture, cables and general moulding.
Where Low-Density Polyethylene is Used
Film applications take the majority of LDPE, with extrusion coating, cable and moulding sharing the rest.
In blown film
LDPE's long chain branching gives the melt strength that keeps the bubble stable at high output and allows thin gauges without breaks. Most commercial film is a blend with LLDPE: the LDPE supplies processability, optics and sealing, the LLDPE supplies tear and puncture strength. Changing the blend ratio changes both the line settings and the film properties.
In extrusion coating
A high MFI LDPE is extruded as a thin curtain onto paper, board or foil at high line speed. Melt strength and neck-in behaviour decide how well it runs, and these are properties of the branching structure rather than of MFI alone — which is why extrusion coating grades are specified separately rather than selected from a film grade list.
Need a specific grade, purity and packing format?
Tell us the grade, the application, MFI and density your line needs, the packing format you can receive and the annual quantity. We will come back with a price, a lead time, a sample COA and the full documentation set.
Quality Control & Testing
Every lot is released against a batch-specific Certificate of Analysis with the grade's defining properties, so your incoming inspection can release against the actual material.
- Melt flow index — at 190 °C and 2.16 kg, the primary processing indicator.
- Density — defining the grade family and stiffness.
- Volatiles and ash — confirming freedom from contamination and residual monomer.
- Mechanical properties — tensile strength and elongation to the grade data sheet.
- Additive package — antioxidant, slip and antiblock levels where specified.
- Pellet appearance — confirming freedom from black specks, fines and angel hair.
Common Process Problems & Likely Causes
When LDPE causes trouble, it is usually grade mismatch, contamination or moisture in conveying. This table is the shortcut our technical desk works through before anyone opens a complaint file.
| Symptom | Likely cause | What to check |
|---|---|---|
| Bubble instability in blown film | MFI or melt strength different from the previous grade | MFI and density against the previous COA; blend ratio |
| Black specks or gels in the film | Contamination in conveying or degraded material in the extruder | Pellet appearance, line purging and screw condition |
| Seal strength low | Seal initiation temperature of the grade, or contamination | Grade data sheet and seal bar temperature |
| Film optics poor | Grade substitution or blend ratio change | Density, MFI and blend composition |
| Angel hair and fines in the hopper | Pellet attrition in pneumatic conveying | Conveying velocity and line design |
| Extrusion coating neck-in excessive | Melt strength lower than the previous grade | Grade selection — coating grades differ from film grades |
Packaging, Storage & Shipping
- Standard packing. 25 kg bags, 500 to 1250 kg jumbo bags, octabins and bulk containers or silo trucks.
- Storage. Dry, covered warehousing away from direct sunlight; UV exposure degrades unstabilised resin over time.
- Temperature. Ambient storage. Avoid prolonged storage above 40 °C, which can cause pellet blocking.
- Conveying. Control conveying velocity to limit fines and angel hair; smooth bends and proper line sizing help.
- Contamination control. Keep silos and conveying lines clean; black specks are almost always a handling issue rather than a resin defect.
- Segregation. Keep grades clearly separated and labelled; mixed grades are a common cause of unexplained process variation.
- Shelf life. Typically 24 months in sealed bags in covered storage.
- Transport classification. Not classified as dangerous goods for transport.
Hazards & Safe Handling
LDPE is an inert polymer with no significant health hazard in normal handling. The practical concerns are molten polymer burns, pellet slip hazards and fume from overheating.
- Inert in normal handling. Not classified as hazardous. Pellets present no chemical risk in storage or transport.
- Molten polymer burns. Melt at 160 to 220 °C adheres to skin and causes severe burns; use proper PPE at the extruder.
- Thermal decomposition fumes. Overheating above about 300 °C releases hydrocarbons and irritating fumes; ventilate processing areas.
- Slip hazard. Spilled pellets are a serious slip hazard on hard floors; clean up promptly.
- Dust and fines. Polyethylene dust from conveying is combustible in high concentration; maintain extraction and housekeeping.
- Environment. Pellet loss to the environment is a recognised marine litter source; containment at every transfer point is expected practice.
Regulatory & Compliance Notes
LDPE is unregulated for transport, with food contact and packaging rules applying downstream. The notes below are orientation rather than legal advice.
- GHS classification. Not classified as hazardous.
- Transport. Not classified as dangerous goods. Standard packaged and bulk cargo documentation applies.
- Food contact. Food grades must comply with EU 10/2011, FDA 21 CFR 177.1520 or equivalent, with declarations of compliance supplied.
- Polymer exemption. Polymers are exempt from REACH registration, though monomers and additives are not.
- Packaging waste regulation. Downstream packaging is subject to recyclability and recycled content requirements in a growing number of markets.
- Pellet loss prevention. Operation Clean Sweep and equivalent programmes set expectations for pellet containment at handling sites.
We Supply Low-Density Polyethylene Worldwide
Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship Low-Density Polyethylene from India and from partner sources to customers across Asia, Europe, the Middle East, Africa, and North and South America, handling the export documentation, transport paperwork and freight so the material arrives ready to use.
- Incoterms. EXW, FOB, CIF, CFR and DAP quoted to suit your purchasing terms and freight arrangements.
- Ports. Regular shipments through Nhava Sheva (JNPT) and Mundra, with other ports arranged where routing and cargo rules allow.
- Documentation. Commercial invoice, packing list, certificate of origin, COA, SDS and the transport declaration issued as a complete set.
- Flexible volumes. From a pallet of bagged resin up to repeat bulk shipments on a supply contract.
- Supply continuity. Because we are independent of any one producer, a plant turnaround or a shipping disruption at one source does not have to become your stock-out.
Buying Low-Density Polyethylene from Chelora
We are an independent sourcing and supply partner. For LDPE that means settling three things at enquiry: the application and the MFI and density it needs, whether food contact or medical compliance is required, and the packing format your plant handles.
- Documentation on every lot. Batch-specific COA (MFI, density, additive package), plus SDS and the full transport paperwork.
- Analysis before commitment. Representative analysis shared ahead of a commercial order so your lab can qualify the material.
- Quantities. From a pallet of bagged resin through to full bulk shipments on contract supply.
- Grade matching. Film, extrusion coating, injection or cable grade at the MFI and density your line requires, with food-contact documentation where needed.
- Inspection. Independent third-party inspection available at loading when the contract requires it.
- Related products. Linear Low-Density Polyethylene, High-Density Polyethylene, Polypropylene and other feedstocks alongside Low-Density Polyethylene from one supplier.
How ordering works
- Send the enquiry. Product, grade or purity, quantity, destination port and the Incoterm you buy on. If you have a spec sheet, attach it — it saves a round trip.
- We quote. Price, lead time, packing format and a sample COA, normally within one working day.
- Qualify the supply. For first orders or critical applications, we share the analysis and handling documentation so your technical and safety teams can sign off before you commit.
- Confirm the order. Proforma invoice issued; payment terms agreed against the volume and the relationship.
- Allocation and QC. Material allocated and released against a batch-specific COA, with an independent inspection where the contract calls for it.
- Ship and document. Filled, labelled and loaded with the full export document set, and tracked through to arrival.
Low-Density Polyethylene — Common Questions
The questions our technical desk is asked most often about Low-Density Polyethylene. If yours isn't here, call or email and you will reach someone who knows the chemistry.
What is the CAS number of LDPE?
The CAS number for polyethylene is 9002-88-4. LDPE is classified under HS code 3901.10. As a polymer it is exempt from REACH registration, though its monomer and additives are not.
What is LDPE used for?
Mainly for blown and cast film — shrink film, bags, liners and lamination film — plus extrusion coating of liquid packaging board, agricultural film, cable insulation, and injection and blow moulded items.
Do you supply LDPE worldwide?
Yes. Chelora Chemicals supplies and exports LDPE worldwide — across Asia Pacific, Europe, the Middle East, Africa and the Americas, as well as throughout India, in bags, jumbo bags, octabins and bulk.
What is the difference between LDPE and LLDPE?
LDPE is made at very high pressure and has long chain branches, giving melt strength, clarity and easy processing. LLDPE is made with catalysts and has short branches, giving higher tensile, tear and puncture strength. Most film blends both.
How is LDPE manufactured?
By free radical polymerisation of ethylene at 1500 to 3000 bar and 150 to 300 °C in autoclave or tubular reactors, with peroxide or oxygen initiators and a chain transfer agent to control melt flow index.
How do I choose a grade?
By MFI and density together, matched to the process: low MFI for film and high melt strength, higher MFI for injection moulding and coating. Two resins with the same MFI can still run differently, so a trial is worth doing on any grade change.
Is LDPE food contact approved?
Specific grades are, under EU 10/2011, FDA 21 CFR 177.1520 and equivalent regimes. The grade and its additive package determine compliance, and we supply the declaration of compliance with food-contact grades.
Is LDPE hazardous?
No. It is an inert polymer not classified as dangerous goods. The practical hazards are burns from molten polymer at the extruder, fume from overheating, and the slip hazard of spilled pellets.
How should LDPE be stored?
In dry, covered warehousing away from direct sunlight, at ambient temperature. Keep grades clearly separated, because mixed grades are a common cause of unexplained process variation.
What causes black specks in film?
Almost always contamination or degraded material in the conveying system or extruder rather than a resin defect. Line purging, screw condition and silo cleanliness are the places to look first.
What packing sizes are available?
25 kg bags, 500 to 1250 kg jumbo bags, octabins and bulk containers or silo trucks. Orders run from a pallet of bagged resin up to full bulk shipments.
What is the typical shelf life?
Around 24 months in sealed bags in covered storage. The limiting factor is UV exposure and additive migration rather than the polymer itself.
Ready to source Low-Density Polyethylene?
Send us your specification, grade and annual volume. You will get a price, a realistic lead time and a sample COA from someone who understands what the material has to do in your process — delivered anywhere in the world.