Polyethylene Terephthalate Resin CAS 25038-59-9
Chelora Chemicals supplies bottle, sheet and film grades of PET resin to preform moulders, sheet extruders and converters worldwide, including food-contact and recycled-content grades. Every consignment leaves with a batch-specific COA covering intrinsic viscosity, colour, acetaldehyde and moisture, the current SDS and full export documentation.
Also known as: PET · PET resin · Polyester resin chip · PET chips · Bottle grade PET
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Price, lead time and a sample COA for Polyethylene Terephthalate Resin, usually within one working day. We ship worldwide.
Request a Quote Email the DeskDocumentation
- Batch-specific COA (IV, colour, acetaldehyde, moisture)
- Safety Data Sheet (SDS)
- Transport and export documents
- Third-party inspection on request
- Certificate of origin
What is Polyethylene Terephthalate Resin?
Polyethylene terephthalate is the polyester of terephthalic acid and ethylene glycol, supplied as clear chips or pellets. It combines clarity, strength, gas barrier and food-contact acceptability in a way no other commodity polymer matches.
Bottle grades are produced by melt polymerisation followed by solid-state polycondensation, which raises intrinsic viscosity and strips acetaldehyde.
Intrinsic viscosity is the defining grade property: around 0.80 dL/g for carbonated soft drink bottles, 0.76 to 0.78 for water, and lower for sheet and fibre.
PET is strongly hygroscopic and hydrolyses in the melt if not dried, which makes drying the single most important processing discipline for every PET converter.
Why PET specifically
- Clarity with strength. Biaxial orientation during blowing gives a clear, tough bottle at low weight.
- Gas barrier. Carbon dioxide retention is good enough for carbonated drinks, which polyolefins cannot achieve.
- Food contact acceptance. Approved worldwide, with established recycled-content streams for bottle-to-bottle recycling.
- Solid-state polycondensation. Allows high IV and very low acetaldehyde, both essential for bottles.
How Polyethylene Terephthalate Resin is Manufactured
PET is made by esterification and polycondensation, with bottle grades taking a further solid-state step.
- Esterification. PTA is slurried with MEG and esterified at about 250 °C without catalyst, releasing water.
- Prepolymerisation. The oligomer is built up under moderate vacuum.
- Melt polycondensation. High vacuum and antimony or titanium catalyst build molecular weight, with glycol removed overhead.
- Pelletising. The melt is extruded, quenched and cut to amorphous chip.
- Crystallisation. Chip is crystallised before solid-state treatment to prevent sticking.
- Solid-state polycondensation. Chip is held at 200 to 220 °C under nitrogen or vacuum to raise IV and strip acetaldehyde to bottle-grade levels.
Typical Commercial Specification
Figures below are representative of a bottle-grade PET resin. Sheet, film and fibre grades differ — tell us the application and we will send the matching sheet.
| Parameter | Typical Value |
|---|---|
| Appearance | Clear colourless chips or pellets, free of contamination |
| Intrinsic viscosity | 0.60 – 0.86 dL/g depending on grade |
| Acetaldehyde content | 1 ppm max for bottle grade |
| Colour L value | Typically 75 min |
| Colour b value | Typically −2 to +2 |
| Moisture as delivered | 0.3% max |
| Melting point | 245 to 255 °C |
| Diethylene glycol content | Typically 1.2 to 1.5% |
| Carboxyl end groups | To grade, typically 25 to 40 mmol/kg |
| Chip size and dust | To grade, low fines |
Physical & Chemical Properties
| Property | Value |
|---|---|
| Chemical formula | (C₁₀H₈O₄)ₙ |
| Appearance | Clear chips; white when crystallised |
| Density | 1.33 to 1.40 g/cm³ |
| Melting point | 245 to 255 °C |
| Glass transition temperature | About 75 to 80 °C |
| Moisture absorption | Strongly hygroscopic, up to 0.6% at equilibrium |
| Drying requirement | To below 50 ppm before processing |
| Chemical resistance | Good to acids and most solvents; attacked by strong alkalis |
| Processing temperature | Typically 270 to 290 °C |
| Gas barrier | Good CO₂ and O₂ barrier for a commodity polymer |
| Incompatibilities | Strong alkalis, hot water over long exposure, strong oxidisers |
Behaviour in the process
PET's hygroscopicity dominates every conversation about processing it:
- Hydrolysis in the melt. Moisture above about 50 ppm causes chain scission at processing temperature, dropping IV and ruining bottle strength.
- Strongly hygroscopic. Dried chip reabsorbs moisture from air within minutes, so the dryer must feed the extruder directly.
- Acetaldehyde regeneration. Excessive melt temperature or residence time regenerates acetaldehyde in the preform.
- Crystallises on heating. Amorphous chip crystallises and sticks if heated carelessly, which is why SSP crystallises first.
PET Grades and Alternatives
PET is bought by intrinsic viscosity and grade family, with the application dictating both.
| Material | Origin / type | When it is the right choice |
|---|---|---|
| Bottle grade PET | IV 0.76 – 0.86 | Carbonated drinks, water and hot-fill bottles |
| Sheet grade PET | IV 0.70 – 0.80 | Thermoformed trays and APET sheet |
| Film grade PET | IV 0.60 – 0.65 | BOPET packaging and technical film |
| Recycled PET (rPET) | Post-consumer, food grade approved | Bottle-to-bottle recycling under content mandates |
| PETG and copolyesters | Glycol modified | Thermoforming and sheet where crystallisation must be suppressed |
Stated plainly: the IV ladder tracks the mechanical demand of the application, and substituting downward to save money will show up as bottle failure under pressure. Recycled content is now a regulatory requirement in many markets rather than a choice.
Industries We Supply Polyethylene Terephthalate Resin To
PET serves beverages, food packaging, films and fibre.
Where Polyethylene Terephthalate Resin is Used
Bottle and preform production takes the largest share of PET resin, with sheet and film behind it.
Drying and processing
PET must be dried to below 50 ppm moisture before processing, typically four to six hours at 160 to 170 °C in a desiccant dryer with a dew point of −40 °C. Undried resin hydrolyses in the melt, dropping IV and producing weak, hazy preforms. Nearly every PET processing complaint we investigate starts at the dryer.
Intrinsic viscosity selection
IV correlates with molecular weight and therefore with mechanical strength and stress crack resistance. Carbonated soft drinks need around 0.80 to 0.84 dL/g to withstand internal pressure; still water can run at 0.76 to 0.78; sheet and film run lower. IV drops by roughly 0.02 to 0.04 dL/g through normal processing, which must be allowed for.
Need a specific grade, purity and packing format?
Tell us the grade, the intrinsic viscosity and whether food contact or recycled content documentation is needed, 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 IV and acetaldehyde reported because they define bottle-grade performance.
- Intrinsic viscosity — the primary grade measure, correlating with molecular weight and strength.
- Acetaldehyde content — critical for water bottles because of taste migration.
- Colour L and b values — confirming clarity and freedom from yellowness.
- Moisture as delivered — confirming the chip was packed dry.
- DEG content and carboxyl end groups — affecting crystallisation and hydrolytic stability.
- Chip size, dust and contamination — confirming handling and melt filtration behaviour.
Common Process Problems & Likely Causes
When PET causes trouble, it is almost always drying, IV or acetaldehyde. This table is the shortcut our technical desk works through before anyone opens a complaint file.
| Symptom | Likely cause | What to check |
|---|---|---|
| Preforms hazy or weak | Moisture causing hydrolysis in the melt | Dryer dew point, temperature and residence time |
| IV drop through processing excessive | Drying inadequate or melt temperature too high | Moisture figure, dryer performance and barrel profile |
| Off-taste in bottled water | Acetaldehyde regenerated during preform moulding | Melt temperature, residence time and AA figure on the COA |
| Bottles failing pressure or stress crack test | IV too low for the application | IV against the bottle specification |
| Yellow tint in preforms | Overheating or catalyst residue | Colour b value and melt temperature profile |
| Chip bridging in the dryer hopper | Fines or moisture causing sticking | Chip dust content and hopper design |
Packaging, Storage & Shipping
- Standard packing. 25 kg bags, 1000 to 1250 kg jumbo bags and bulk containers or silo trucks.
- Moisture protection. PET is strongly hygroscopic; keep bags sealed until use and dry the chip immediately before processing.
- Drying. Dry to below 50 ppm, typically four to six hours at 160 to 170 °C with a dew point of −40 °C.
- Storage. Dry, covered warehousing at ambient temperature on pallets.
- Conveying. Dried chip must be conveyed in dry air; ambient air conveying reintroduces moisture within minutes.
- Contamination control. Keep lines and silos clean; contamination shows immediately in clear bottles.
- Shelf life. Typically 24 months in sealed bags in dry storage.
- Transport classification. Not classified as dangerous goods for transport.
Hazards & Safe Handling
PET is an inert polymer with no significant health hazard in normal handling. The practical concerns are molten polymer burns, hot dryer surfaces and pellet slip hazards.
- Inert in normal handling. Not classified as hazardous. Chips present no chemical risk in storage or transport.
- Molten polymer burns. Melt at 270 to 290 °C adheres to skin and causes severe burns; use proper PPE at the machine.
- Hot dryer surfaces. Dryers run at 160 to 170 °C with hot air; burns from hoppers and ducting are a real risk.
- Thermal decomposition. Overheating releases acetaldehyde and other volatiles; ventilate processing areas.
- Slip hazard. Spilled chip is a serious slip hazard; clean up promptly.
- Environment. Pellet loss to the environment is a recognised litter source; containment at every transfer point is expected practice.
Regulatory & Compliance Notes
PET is unregulated for transport, with extensive food contact and recycled content regulation 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. Must comply with EU 10/2011, FDA 21 CFR 177.1630 or equivalent, with declarations of compliance supplied.
- Recycled content. The EU Single-Use Plastics Directive and similar rules mandate minimum recycled content in beverage bottles, with rPET requiring EFSA or FDA process approval.
- Acetaldehyde limits. Specified contractually rather than by regulation for water bottles, because of taste rather than toxicity.
- Polymer exemption. Polymers are exempt from REACH registration, though monomers and additives are not.
We Supply Polyethylene Terephthalate Resin Worldwide
Chelora Chemicals is a supplier and export partner, not a single-plant trader. We ship Polyethylene Terephthalate Resin 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 chip 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 Polyethylene Terephthalate Resin from Chelora
We are an independent sourcing and supply partner. For PET that means settling three things at enquiry: the intrinsic viscosity your application requires, whether food contact and recycled content documentation are needed, and the drying capability at your plant.
- Documentation on every lot. Batch-specific COA (IV, colour, acetaldehyde, moisture), 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 chip through to full bulk shipments on contract supply.
- Grade matching. Bottle, sheet, film or fibre grade at the intrinsic viscosity and acetaldehyde level your application requires, virgin or with recycled content.
- Inspection. Independent third-party inspection available at loading when the contract requires it.
- Related products. Purified Terephthalic Acid, Mono Ethylene Glycol, Para-Xylene and other feedstocks alongside Polyethylene Terephthalate Resin 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.
Polyethylene Terephthalate Resin — Common Questions
The questions our technical desk is asked most often about Polyethylene Terephthalate Resin. If yours isn't here, call or email and you will reach someone who knows the chemistry.
What is the CAS number of PET resin?
The CAS number for polyethylene terephthalate is 25038-59-9, and bottle-grade resin is classified under HS code 3907.61. As a polymer it is exempt from REACH registration.
What is PET resin used for?
For beverage bottles and preforms, thermoformed food trays and sheet, BOPET packaging and technical film, polyester fibre, and industrial strapping.
Do you supply PET resin worldwide?
Yes. Chelora Chemicals supplies and exports PET resin worldwide — across Asia Pacific, Europe, the Middle East, Africa and the Americas, as well as throughout India, in bags, jumbo bags and bulk, including food-contact and recycled-content grades.
What is intrinsic viscosity and how do I choose it?
IV correlates with molecular weight and mechanical strength. Carbonated soft drinks need about 0.80 to 0.84 dL/g; still water 0.76 to 0.78; sheet and film lower. IV drops slightly through processing, which must be allowed for in the selection.
Why must PET be dried before processing?
Because PET is strongly hygroscopic and hydrolyses in the melt. Moisture above about 50 ppm causes chain scission, dropping IV and producing weak, hazy preforms. Drying is the single most important PET processing discipline.
How is PET resin manufactured?
By esterifying PTA with MEG, then polycondensing under vacuum to amorphous chip. Bottle grades are then crystallised and solid-state polycondensed at 200 to 220 °C to raise IV and strip acetaldehyde.
What is acetaldehyde and why does it matter?
A by-product generated during melt processing. It migrates into bottled water and gives a detectable off-taste at very low concentrations, so bottle grade is specified at 1 ppm or below and preform processing is tuned to limit regeneration.
Is PET food contact approved?
Yes, under EU 10/2011, FDA 21 CFR 177.1630 and equivalent regimes. Recycled PET for food contact requires separate process approval from EFSA, FDA or the relevant authority.
Is PET hazardous?
No. It is an inert polymer not classified as dangerous goods. The practical hazards are burns from molten polymer and hot dryers, and the slip hazard of spilled chip.
What are the drying conditions for PET?
Typically four to six hours at 160 to 170 °C in a desiccant dryer with a dew point of −40 °C, conveyed to the machine in dry air. Dried chip reabsorbs moisture from ambient air within minutes.
Can I use recycled PET for bottles?
Yes, where the rPET has food-contact process approval. Several markets now mandate minimum recycled content in beverage bottles, and approved rPET sometimes trades above virgin resin as a result.
What packing sizes are available?
25 kg bags, 1000 to 1250 kg jumbo bags and bulk containers or silo trucks. Orders run from a pallet of bagged chip up to full bulk shipments.
Ready to source Polyethylene Terephthalate Resin?
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.