Flexible Packaging Materials: Films, Foils, Laminates and Barrier Materials

Flexible packaging materials are the films, foils, coatings and papers combined into pouches, wraps and lids. A mismatched barrier or sealant can shorten shelf life or leave seals unreliable. Select each layer for its job: sealing, printing, stiffness or barrier. To read any structure, you need to know what each family does well and where it falls short.

Materials come first in the site’s chain of material, properties, format, machine and application. This page maps the families. The linked pages cover each one in detail, and flexible packaging explains how the pieces fit together.

Choose a material by its role

Use these as candidates, not measured rankings. Thickness, grade and converting change the result.

The main material families

Polyolefins: PE and PP

Polyethylene (PE) is the standard sealant. It seals at relatively low temperatures, resists moisture and is tough, which is why it sits on the inside of most pouches. LDPE, LLDPE and HDPE differ in stiffness, clarity and seal behavior; see PE film, and the individual grades in LDPE film, LLDPE film and HDPE film. Polypropylene comes as cast polypropylene (CPP), used for sealing and clarity, and as biaxially oriented polypropylene (BOPP), a stiff, clear, printable film covered in BOPP film. The polypropylene film overview compares the family, and CPP film covers the cast grade in detail. Both are good moisture barriers and weak oxygen barriers.

Polyester: PET and BOPET

Oriented PET is stiff, heat resistant, dimensionally stable and prints very well. It is the usual outer layer in laminates and the base for metallized and oxide-coated films. It also has moderate oxygen barrier compared with the polyolefins. See PET film.

Polyamide: nylon and BOPA

Nylon adds puncture and flex resistance, which is why it appears in vacuum pouches and structures for sharp or heavy contents. It absorbs moisture, which changes its properties, and it is a moderate oxygen barrier. It is available as cast and as biaxially oriented film; see nylon film.

EVOH

Ethylene vinyl alcohol is among the best oxygen barrier polymers in dry conditions. It is usually coextruded as a thin inner layer and loses barrier as humidity rises, so it is typically protected between moisture-resistant layers. See EVOH film and barrier film.

PVDC coatings

Polyvinylidene chloride coatings provide both oxygen and moisture barrier in a thin layer. They are used on films like BOPP and PET and in some pharmaceutical and food packaging, though the chlorine content has led some brand owners and regions to move away from them.

Metallized films

A vacuum-deposited layer of aluminum, a fraction of a micron thick, is applied to PET, BOPP, CPP or other substrates. It improves oxygen, moisture and light barrier compared with the base film at much lower cost and weight than foil. Metallized layers can crack with flexing. See metallized film.

Oxide-coated films (AlOx and SiOx)

Aluminum oxide or silicon oxide is deposited on a film, usually PET, to produce a transparent barrier. They offer transparent oxygen and moisture barrier. A manufacturer’s transparent-barrier film description describes microwave heating and metal-detector compatibility for its non-metallic barrier film. That is a coating/film characteristic: the complete laminate, inks, adhesives, closures and intended heating conditions still need confirmation. Like metallization, they can lose barrier if flexed or creased. See high barrier film.

Aluminum foil

Foil is the benchmark for barrier. Intact foil is a complete barrier to gas, moisture and light, though thin foil can have pinholes. It is heavier and less recyclable in laminates, and it can crack when folded. See aluminum foil packaging and blister foil. Foil is also used as a heat-seal cover in lidding foil, as the forming web in cold form foil, and in full-foil alu-alu blisters.

Paper

Paper gives stiffness, a print surface and a natural look. On its own it has little barrier, so it is combined with PE, foil or other coatings. Paper-based packs are a growing part of sustainable flexible packaging, though barrier and heat-seal demands limit where paper works.

For paper-coating news, the paper-coating dispersion carbon-claim review keeps binder carbon accounting separate from complete-package performance.

For liquid sample materials, the coated-paper sachet review distinguishes the reported trial from coating, seam and recovery evidence.

Shrink films: PVC, PETG, POF

Shrink films are oriented during manufacture and shrink when heated, to wrap products tightly. PVC shrink film, PETG shrink film and POF shrink film differ in shrink behavior, clarity, seal strength and end-of-life concerns. OPS shrink film is a further option for full-body sleeves. The overview is in shrink film.

For emerging food-pack materials, the PEF agreement review separates conditional future supply from tray, lid and barrier evidence.

Choosing between similar materials

Some decisions come down to two close options. PET vs BOPP film compares the two common outer webs, while BOPP vs CPP separates oriented from cast polypropylene. Within polyethylene, LDPE vs LLDPE explains why blends are common. For shrink sleeves, compare PVC vs PETG and PETG vs OPS, and for pharmaceutical blisters, blister foil vs cold form foil sets lidding against forming foil.

From material to structure

Materials rarely stand alone. They are assembled by coextrusion or lamination into structures like PET/AL/PE or BOPP/metBOPP/CPP. Layer arrangement and bonding are covered in flexible packaging film, and the polymer-by-polymer comparison is in packaging film types. Barrier is covered in barrier film and high barrier film.

For a current coffee-pouch announcement, the coffee-pouch material evidence review separates the valve description from film, seal and recycling documents.

Choosing materials step by step

1. Start with the product. List what it must be protected from (oxygen, moisture, light, aroma loss, grease, puncture) and for how long.
2. Set barrier targets with test conditions. Use OTR and WVTR numbers measured at stated temperature and humidity, then see what each material can reach. Shelf-life testing confirms the choice.
3. Pick the sealant for the machine and the seal need. The sealant has to run on your equipment; see machine compatibility.
4. Choose the outer layer for print and stiffness. PET and BOPP are the most common options.
5. Check end-of-life. Mono-material and recyclable designs limit your combinations. Regulations and collection systems vary by market, so confirm the rules for where you sell.
6. Compare suppliers on data sheets, not names. The specification guide lists what to ask.

The property differences quoted here are general, so confirm any figure with the supplier’s data sheet for the specific grade.

Where flexible packaging fits among the types of packaging materials

There is no single standard list of “the 7 types of packaging materials”. Lists of seven usually come from splitting packaging by base material. One verifiable way to arrive at seven is the US EPA’s containers and packaging data for 2018, which reports glass, steel, aluminum, paper and paperboard, plastics, wood, and a small group of other materials such as textile bags. Other sources count differently. Eurostat’s 2023 packaging-waste data, extracted in October 2025, groups aluminium and steel together as metal. Treat any count as a framework, not an industry rule.

The common film, foil and paper structures covered on this site draw on three of those groups, and often combine them. Some flexible packs are made from other materials, such as textile bags, which the EPA counts under “other”, or cellulose-based films. This hub does not cover them:

This is why a material-by-material list fits film-based flexible packaging badly. A single pouch can be PET, aluminum foil and PE at once, so this page sorts materials by the job they do in a structure instead. Barrier packaging materials are not a separate group either: they are plastics such as EVOH, aluminum as foil or metallizing, or thin coatings such as PVDC, AlOx and SiOx. The family descriptions above cover these roles.

Sources and method

The EPA and Eurostat links above describe waste-reporting categories, not film grades. The transparent-coating link is a manufacturer’s public description, not a recommendation or a test by this site. Sources checked October 8, 2026; the role matrix organizes selection checks rather than specifying performance values.