PE Film Design Guidance

PE Film Design Guidance

PREFERRED

Polyethylene mono-material flexible packaging

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Pure polyethylene, whether bio-based or not, integrates well with flexible films collection streams and is easily recyclable into various end-use applications like new flexible films, composite lumber, and molded plastic products. With a mix of PE grades in the supply stream, individual packages could consist of different PE grades as defined by ISO 472:2013, such as HDPE, LDPE, LLDPE, MDPE, and VLDPE. Special PE grades like plastomers, mLLDPE, and ULDPE are also considered "Preferred."

APR company data and evaluation by the APR Film Committee show that EVA copolymers designed for film extrusion fall into the “Preferred” category at any weight percentage, as long as vinyl acetate (VA) levels are 5% or less of the total package weight.

One company received Critical Guidance Recognition for a branded ionomer copolymer intended for film extrusion. Based on the chemical similarities of ethylene copolymer ionomers, it was demonstrated that they don’t impact recyclability when used up to 20% in PE formulations. As such, they are listed as “Preferred” when under 20% of the total package weight.

Polybutenes (PB) are generally used in small amounts on PE "easy peel" film formulations, with no adverse effects on recycling. Therefore, PB is accepted in the "Preferred" category up to 5% of the total weight.

A minimum of 90% PE and copolymers by weight of the total packaging structure is preferred for full compatibility with the PE mechanical recycling process to maintain the quality and value of the final recyclate. This is a guideline threshold but not an absolute rule. Ethylene copolymers and other non-PE materials could be included above 10% after being properly tested for recyclability based on the APR Critical Guidance Protocol.

Postconsumer PE content

Using PCR PE in all packages is encouraged to the maximum amount that is technically and economically feasible.

DETRIMENTAL

Less than 90% PE

Structures containing 80-90% PE and copolymers by weight of the total package may pose technical challenges for the recycler’s yield, productivity, or final product quality. Such structures are considered detrimental until tested, and film designers should consult other sections for specific guidelines.

RENDERS NON-RECYCLABLE

PET, PVC, PVDC, Paper, Aluminum foil, or degradable polymers

These polymers contaminate polyolefin recycling streams, significantly degrading the quality of recycled polyolefins and disrupting the recycling process.

PET is chemically and rheologically incompatible with polyethylene and its copolymers, melting at much higher temperatures and causing film defects (“unmelts”) that compromise quality.

PVC and PVDC layers degrade at low temperatures, rendering large portions of recycled PE unusable.

Paper or aluminum-foil-containing materials are unsuitable for recycling within the polyolefin stream, causing significant issues in the recycling process.

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Degradable polymers: These polymers, including PLAs, PHAs, PHBs, PHVs, PBS, cellulose acetate, and starch-based polymers, are designed to degrade, thus diminishing the reuse life of the recycled material. If not removed during recycling, they can shorten the lifespan of products made from the recycled film, compromising their quality and durability.

REQUIRES TEST RESULTS

Less than 80% PE

Structures with less than 80% PE of the total package will likely impact the yield and quality of recycled plastic, necessitating testing to determine the appropriate APR recyclability category.

Blends, coextrusion, or lamination of PE and other resins

Blends or layers of non-PE materials at any level (%) require testing for compatibility in the PE recycling process. These materials either melt and blend with PE during recycling or need filtering. Testing must confirm that these layers do not adversely affect the recycled PE.

Specific examples requiring testing include:

• EVOH
• PVOH
• Nylon (PA)
• Polypropylene (PP)

Several compatibilizers are available that may allow non-compatible materials to blend with PE without negative effects. Successfully demonstrated for films including EVOH and nylon, providers must present evidence of effective compatibilization by testing specific formulations. One company has received Critical Guidance Recognition for a multi-layer PE film including COC content.

Other material combinations at any level also require testing for recycling eligibility. Examples include:

• COC
• PS
• EPCs
• PB (above 5%)
• Engineering thermoplastics like PBT’s and PC’s
• Crosslinked polymer layers
• Elastomeric materials
• Nonwoven (Tyvek® and others)
• Other fiber-based materials

Additionally, specific PE copolymer categories needing testing include:

• Acid copolymers (EAA & EMAA)
• Ester copolymers (EMA, EEA, EBA)
• Ionomers (above 20%)

Tie resins/layers, used for bonding incompatible layers in coextruded or laminated films, are typically grafted-polyethylene copolymers. They don't require independent testing but need to validate the recyclability of non-PE materials listed above.

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