High-Density Polyethylene CAS 9002-88-4
Chelora Chemicals supplies blow moulding, injection, pipe and film grades of high-density polyethylene to converters and compounders worldwide. Every consignment leaves with a batch-specific COA covering melt index, density, ESCR and additive package, the current SDS and full export documentation.
Also known as: HDPE · PE-HD · High density PE · PE100 / PE80 (pipe grades) · Polythene
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Price, lead time and a sample COA for High-Density Polyethylene, usually within one working day. We ship worldwide.
Request a Quote Email the DeskDocumentation
- Batch-specific COA (melt index, density, ESCR)
- Safety Data Sheet (SDS)
- Transport and export documents
- Third-party inspection on request
- Certificate of origin
What is High-Density Polyethylene?
High-density polyethylene is the linear, minimally branched form of polyethylene, made at low pressure over Ziegler-Natta or chromium catalysts. Density runs from 0.940 to 0.965 g/cm³.
The linear chains pack closely, giving high crystallinity and with it stiffness, barrier properties and environmental stress crack resistance that LDPE cannot approach.
Applications split across blow moulded bottles and containers, pressure pipe, injection moulded crates and closures, and HMHDPE film for carrier bags and liners.
Pipe grades are a specialised sub-family, classified as PE80 and PE100 by long-term hydrostatic strength, and they carry certification requirements that ordinary grades do not.
Why HDPE specifically
- Linear, highly crystalline chains. Give stiffness, tensile strength and moisture barrier well above LDPE.
- Environmental stress crack resistance. Bimodal grades resist cracking under load and chemical contact, which is what makes 50-year pipe possible.
- Chemical inertness. Resistant to acids, alkalis and most solvents at ambient temperature.
- Recyclability. One of the most widely and successfully recycled plastics, with established HDPE recyclate streams.
How High-Density Polyethylene is Manufactured
HDPE is made by low-pressure catalytic polymerisation of ethylene, with bimodal technology used for the demanding grades.
- Ethylene feed. Polymer-grade ethylene, with a small amount of butene or hexene comonomer for density control.
- Catalyst system. Ziegler-Natta or chromium catalysts, with bimodal processes using two reactors in series.
- Slurry or gas phase polymerisation. Slurry loop and gas phase fluidised bed are the dominant routes at 20 to 40 bar.
- Bimodal grades. Two reactors produce a blend of high and low molecular weight fractions in one resin, giving stiffness and ESCR together.
- Degassing. Residual monomer is stripped from the polymer powder.
- Compounding and pelletising. Antioxidants, UV stabilisers and carbon black for pipe grades are added before pelletising.
Typical Commercial Specification
Figures below are representative of a general-purpose blow moulding grade. Each grade has its own data sheet — tell us the application and we will send the matching one.
| Parameter | Typical Value |
|---|---|
| Appearance | Translucent to opaque pellets, free of contamination |
| Melt index (190 °C / 2.16 kg or 5 kg) | 0.03 – 25 g/10 min depending on grade |
| Density | 0.940 – 0.965 g/cm³ |
| ESCR (F50) | To grade data sheet, critical for containers and pipe |
| Tensile strength at yield | Typically 22 – 32 MPa |
| Flexural modulus | Typically 900 – 1500 MPa |
| Volatiles | 0.05% max |
| Carbon black content (pipe grades) | 2.0 – 2.5% |
| Additive package | Antioxidant and UV stabiliser to grade |
Physical & Chemical Properties
| Property | Value |
|---|---|
| Chemical formula | (C₂H₄)ₙ |
| Appearance | Translucent to opaque white pellets; black for pipe grades |
| Density | 0.940 – 0.965 g/cm³ |
| Melting range | About 125 to 135 °C |
| Crystallinity | Typically 60 to 80% |
| Water absorption | Negligible, under 0.01% |
| Chemical resistance | Excellent to acids, alkalis, salts and most solvents at ambient |
| Service temperature | Typically −50 to 80 °C |
| Processing temperature | Typically 180 to 240 °C |
| Thermal stability | Degrades above about 300 °C |
| Incompatibilities | Strong oxidisers; swelling by hydrocarbons at elevated temperature |
Behaviour in the process
HDPE's crystallinity gives it both its strengths and its characteristic processing behaviours:
- High shrinkage. Crystallinity means more shrinkage on cooling than amorphous polymers; mould design must allow for it.
- Warpage sensitivity. Differential cooling causes warping in flat injection mouldings; gate and cooling design matter.
- Stress crack sensitivity. Lower molecular weight grades crack under combined stress and surfactant contact; ESCR selection is critical.
- Poor adhesion. Non-polar surface resists printing and bonding; flame or corona treatment is normally needed.
HDPE Grades and Alternative Polymers
HDPE is bought by grade family, and the application dictates the family far more than price does.
| Material | Origin / type | When it is the right choice |
|---|---|---|
| Blow moulding HDPE | Low melt index, high ESCR | Bottles, jerricans and containers |
| Injection moulding HDPE | Higher melt index | Crates, closures and housewares |
| Pipe grade PE100 | Bimodal, black, certified | Pressure water and gas pipe with 50-year design life |
| HMHDPE film grade | Very high molecular weight | Thin, strong carrier bags and liners |
| Polypropylene | CAS 9003-07-0 | Higher stiffness and temperature resistance, lower impact at low temperature |
Stated plainly: pipe grades are not interchangeable with container grades even at similar melt index, because the certification rests on long-term hydrostatic testing of the specific resin. Substituting in a pressure application is a compliance issue, not a technical preference.
Industries We Supply High-Density Polyethylene To
HDPE serves packaging, infrastructure, consumer goods and industrial applications.
Where High-Density Polyethylene is Used
Blow moulding and pipe take the largest HDPE volumes, with injection moulding and film close behind.
In pressure pipe
PE100 pipe resins are bimodal: a high molecular weight fraction carrying comonomer gives slow crack growth resistance, while a low molecular weight fraction gives processability. Classification rests on long-term hydrostatic testing, and the carbon black package provides UV protection. This is why pipe grades are certified products rather than ordinary commodity resin.
In blow moulding
Container grades are selected on ESCR as much as on melt index, because detergent and bleach bottles fail by stress cracking rather than by bursting. Die swell and parison sag govern wall thickness distribution, and both are resin properties, so a grade change usually means re-tuning the parison programme.
Need a specific grade, purity and packing format?
Tell us the grade, the application, melt index, density and ESCR your part requires, 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 index — at 190 °C under the load specified for the grade.
- Density — defining stiffness and the grade family.
- ESCR — the critical property for containers and pipe.
- Tensile and flexural properties — to the grade data sheet.
- Carbon black content and dispersion — for pipe grades, confirming UV protection.
- Volatiles, ash and pellet appearance — confirming freedom from contamination.
Common Process Problems & Likely Causes
When HDPE causes trouble, it is usually grade selection, ESCR or processing conditions. This table is the shortcut our technical desk works through before anyone opens a complaint file.
| Symptom | Likely cause | What to check |
|---|---|---|
| Bottles cracking in service | ESCR of the grade too low for the contents | ESCR figure and grade selection against the fill |
| Warping in injection mouldings | Differential cooling and high crystalline shrinkage | Mould cooling, gate design and grade shrinkage data |
| Parison sag or uneven wall thickness | Melt index or die swell different from the previous grade | Melt index and parison programme settings |
| Pipe failing pressure test | Grade not certified for the duty, or fusion jointing fault | PE classification documentation and jointing procedure |
| Print or label adhesion poor | Untreated non-polar surface | Flame or corona treatment level |
| Black specks or gels | Contamination or degraded material in the line | Pellet appearance, purging and screw condition |
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; natural grades are UV sensitive without stabilisation.
- Temperature. Ambient storage; avoid prolonged exposure above 40 °C.
- Grade segregation. Keep pipe, blow and injection grades strictly separated; cross-contamination in pipe grades is a compliance problem.
- Conveying. Control velocity to limit fines and angel hair.
- Contamination control. Clean silos and lines between grades, particularly before pipe grade runs.
- Shelf life. Typically 24 months in sealed bags in covered storage.
- Transport classification. Not classified as dangerous goods for transport.
Hazards & Safe Handling
HDPE 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 180 to 240 °C adheres to skin and causes severe burns; use proper PPE at the machine.
- 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; clean up promptly.
- Dust and fines. Polyethylene dust 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
HDPE is unregulated for transport, with food contact, drinking water and pipe certification applying by application. 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 comply with EU 10/2011, FDA 21 CFR 177.1520 or equivalent, with declarations of compliance supplied.
- Drinking water approval. Pipe for potable water requires national approvals such as WRAS, KTW, NSF 61 or equivalent.
- Pipe classification. PE80 and PE100 classification rests on long-term hydrostatic testing under ISO 9080 and related standards.
- Pellet loss prevention. Operation Clean Sweep and equivalent programmes set expectations for pellet containment at handling sites.
We Supply High-Density Polyethylene Worldwide
Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship High-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 High-Density Polyethylene from Chelora
We are an independent sourcing and supply partner. For HDPE that means settling three things at enquiry: the application and the grade family it requires, the ESCR or pipe classification your part must meet, and whether food contact or drinking water approval documentation is needed.
- Documentation on every lot. Batch-specific COA (melt index, density, ESCR), 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. Blow, injection, pipe or film grade at the melt index, density and ESCR your application requires, with pipe classification documentation where needed.
- Inspection. Independent third-party inspection available at loading when the contract requires it.
- Related products. Low-Density Polyethylene, Linear Low-Density Polyethylene, Polypropylene and other feedstocks alongside High-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.
High-Density Polyethylene — Common Questions
The questions our technical desk is asked most often about High-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 HDPE?
The CAS number for polyethylene is 9002-88-4. HDPE is classified under HS code 3901.20. As a polymer it is exempt from REACH registration, though its monomer and additives are not.
What is HDPE used for?
For blow moulded bottles, jerricans and drums; pressure pipe for water and gas; injection moulded crates, closures and housewares; HMHDPE carrier bags and liners; geomembranes and rotomoulded tanks.
Do you supply HDPE worldwide?
Yes. Chelora Chemicals supplies and exports HDPE 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 ESCR and why does it matter?
Environmental stress crack resistance measures how a resin withstands combined mechanical stress and chemical contact. Detergent bottles and pressure pipe fail by stress cracking rather than bursting, so ESCR often matters more than tensile strength.
What is the difference between PE80 and PE100?
They are pipe classifications based on long-term hydrostatic strength: PE80 withstands 8 MPa and PE100 withstands 10 MPa over a 50-year design life at 20 °C. PE100 resins are bimodal, allowing thinner walls at the same pressure rating.
How is HDPE manufactured?
By low-pressure catalytic polymerisation of ethylene over Ziegler-Natta or chromium catalysts in slurry loop or gas phase reactors, with bimodal grades made in two reactors in series to combine stiffness and stress crack resistance.
What is the difference between HDPE and LDPE?
HDPE is linear and highly crystalline, giving stiffness, barrier and stress crack resistance. LDPE is branched, giving melt strength, clarity and easy processing but much lower rigidity and ESCR.
Is HDPE food contact approved?
Specific grades are, under EU 10/2011, FDA 21 CFR 177.1520 and equivalent regimes. Drinking water pipe additionally requires national approvals such as WRAS, KTW or NSF 61.
Is HDPE hazardous?
No. It is an inert polymer not classified as dangerous goods. The practical hazards are burns from molten polymer, fume from overheating and the slip hazard of spilled pellets.
Why does HDPE need surface treatment before printing?
Because the non-polar surface gives poor adhesion to inks and adhesives. Flame or corona treatment raises surface energy enough for printing and labelling to hold.
How should HDPE be stored?
In dry, covered warehousing away from direct sunlight, with grades strictly separated. Pipe grades in particular must not be cross-contaminated, since that undermines the pressure classification.
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.
Ready to source High-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.