Table of Contents
Reviewed and updated by ICD - Week 44/2026
PE film is soft, tough and stretchy; PET film is stiff, clear and a much better gas barrier. PE is the choice for bags, wrapping film and pallet stretch wrap; PET is the choice for bottles, trays and packaging that must hold in gas or needs clarity. The two do not replace each other: PE wins on flexibility and on the price of commodity resin, PET wins on stiffness, clarity and oxygen barrier. This article compares them with sourced figures so you can choose correctly for PE film or PET packaging.
1. Quick comparison of PE and PET
| Criterion | PE film | PET film |
|---|---|---|
| Density | 0.910 - 0.940 g/cm³ (LDPE), from 0.941 (HDPE) | about 1.39 g/cm³ (oriented film) |
| Melting point | LDPE 105 - 115 °C; HDPE 120 - 130 °C | about 253 °C |
| Oxygen barrier, OTR (cc/m²/day) | LDPE 2,000 - 8,000 | 45 - 65 |
| Water vapour barrier, WVTR (g/m²/day) | LDPE 10 - 30 | 3 - 5 |
| Stiffness | Soft, stretchy | Stiff, strong in tension |
| Clarity | From hazy to clear | Very clear, glossy |
| Heat sealing | Yes, used as the sealing layer | Does not seal to itself like PE; needs a coating or lamination |
Density and melting point of PE are from Wikipedia, Polyethylene; of PET from Kunststoff-Profi and Breil (2016). OTR and WVTR are from the Polfilm comparison table and are typical ranges for commodity films, not for a specific batch of film, so when an exact figure is needed, check the manufacturer’s datasheet.
2. Why PET is a better gas barrier than PE
In numbers, oxygen passes through LDPE film about 30 to 180 times faster than through PET according to the table above. That is why carbonated drink bottles and coffee packaging need PET or another barrier layer, while plastic bags and pallet wrap do not need a gas barrier. On water vapour, by contrast, PE is not weak: both block moisture well, and PE is often used as the final sealing layer in multi-layer laminated films. According to CEFLEX, PE blocks moisture well but gas poorly, which suits its role as the inner layer of laminated packaging.
3. Temperature: do not confuse melting point with usable temperature
LDPE melts at 105 to 115 °C but should only be used continuously up to about 80 °C; the heat deflection temperature of LDPE under load is only about 45 °C (CP Lab Safety). PET melts at about 253 °C and has a glass transition at about 75 °C, so above that PET bottles usually start to soften and deform even though they have not melted. Oriented PET film used in cook-in or ovenable laminated packaging can withstand over 200 °C for a short time according to CEFLEX; that figure does not apply to PET bottles. So a fair comparison must use the same product form: film with film, bottle with bottle.
| Temperature | PE | PET |
|---|---|---|
| Glass transition (Tg) | about -25 °C | about 75 °C |
| Melting (Tm) | LDPE 105 - 115 °C; HDPE 120 - 130 °C | about 253 °C |
| Maximum usable temperature usually stated | LDPE about 80 °C | depends on form, bottles usually under 75 °C |
PE has a very low Tg, so it stays flexible in the cold. The Tg of PE is from CP Lab Safety, the Tg of PET from Kunststoff-Profi.
4. Printing and clarity
PET has a flat surface and a higher surface energy, so it takes ink well and gives sharp colour; Breil gives the surface tension of BOPET as 50 to 55 dyn against 40 dyn for BOPP. PE generally needs corona surface treatment before printing for the ink to adhere. On clarity, oriented PET gives a higher gloss than PE, so films that must show off the goods, such as bakery trays, salad boxes and bottles, are usually PET.
5. Which to choose for your job
Choose PE when you need softness, stretch and easy heat sealing: bags, wrapping film, impact-resistant packaging, and above all pallet stretch wrap. Pallet wrap is made from LLDPE because it must stretch, cling to itself and hold the load tight; PET is too stiff and does not cling, so it cannot do this job. ICD Vietnam supplies hand stretch film 17 micron thick, 500 mm wide, and machine stretch film rolls 20 to 30 micron thick; to estimate the cost, see how to calculate PE film weight.
Choose PET when you need stiffness, clarity and a gas barrier: carbonated drink bottles, food trays, multi-layer coffee packaging, and film with sharp printed colour. If you need both a gas barrier and heat sealing, packaging in practice often laminates PET with PE in the same film rather than choosing one of the two.
Frequently asked questions
How do PE film and PET film differ?
PE is soft, tough, stretchy and a poor oxygen barrier; PET is stiff, clear and a better oxygen barrier by about 30 to 180 times according to the usual OTR ranges (45-65 against 2,000-8,000 cc/m²/day). The difference comes from the structure of the molecular chains.
Which is more heat resistant, PE or PET film?
PET melts at about 253 °C, far higher than LDPE at 105-115 °C. However, PET bottles start to soften at about 75 °C, so the comparison should use the same product form.
Which resists UV better?
Neither resists UV on its own. For outdoor use a UV stabiliser must be added.
Which is used for food?
Both have food contact grades, but it must be the right virgin grade with the proper certification. Do not use film of unknown origin for food.
Why is pallet stretch wrap made from PE and not PET?
Pallet wrapping needs film that stretches, clings to itself and holds the load tight. LLDPE can do this; PET is stiff and does not cling, so it is not suitable.
Contact ICD Vietnam for advice
ICD Vietnam Industrial Manufacturing Co., Ltd.
North: 3rd Floor, Thang Long A1 Building, Bau Hamlet, Thien Loc Commune, Hanoi, 0983 797 186 / 090 345 9186 / 090 5859 186
South: 551/212 Le Van Khuong Street, Tan Thoi Hiep Ward, District 12, Ho Chi Minh City, 098 6784 186
Email: sales@icdvietnam.com.vn
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References
- Wikipedia, Polyethylene (classification by density, melting point, UHMWPE, PEX, 34% market share) - en.wikipedia.org
- Kunststoff-Profi, Glass Transition & Melting Temperature of Plastics (Tg and Tm table by DSC) - kunststoff-profi.de
- Polfilm, Comparison of Packaging Films by OTR and WVTR (PET, LDPE, BOPP, PA, EVOH) - polfilm.net
- J. Breil, Oriented Film Technology (properties table of BOPP, BOPET, BOPA; BOPET density 1.393 g/cm³) - kinampark.com
- CEFLEX, Separate Materials and their properties (PE, PP, PET, PA in flexible packaging) - guidelines.ceflex.eu
- CP Lab Safety, Temperature and Permeability Chart (LDPE maximum 80 °C, HDT 45 °C) - cplabsafety.com
