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100Module 7 of 15

Plastics & Flexible Packaging

PE, PP, PET, multilayer films; OTR/MVTR, seal layers, ink adhesion. Choosing mono-materials for recyclability.

7 minutes
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Lesson Video
Plastics & Flexible Packaging
Module Content

1) Executive Summary

5–7 critical insights
  1. Regulation has moved. The EU’s Packaging & Packaging Waste Regulation (PPWR) is now law as Regulation (EU) 2025/40, introducing recyclability-at-scale criteria, harmonized labelling, and eco-modulated fees tied to design for recycling. Expect delegated acts to define binding design rules and grades. [1]
  2. Mono-material is a threshold, not a slogan. For PE films, RecyClass class A requires ≥95% PE by weight; EVOH ≤5% can be tolerated with conditions; metallisation is non-compatible. Clear ceramic barriers (SiOx/AlOx without extra primers) can be compatible depending on polymer. [2]
  3. US is shifting via state-level EPR. Maine, Oregon (changes from July 2025), Colorado, and California (SB 54) are implementing producer-funded systems with registration, reporting, and eco-modulated fees. [3]
  4. UK deadlines matter. Plastic Packaging Tax rate £223.69/tonne from 1 Apr 2025 for <30% PCR; Simpler Recycling mandates kerbside collection of plastic films by 31 Mar 2027 with binary OPRL labelling. [4]
  5. Barrier science in one line. OTR/MVTR depend on material, thickness, and humidity. Indicative values: plain 20 µm BOPP OTR ≈ 2000–2500, WVTR ≈ 4–7; plain 12 µm PET OTR ≈ 100–150, WVTR ≈ 40–50; metallized PET (OD≈2.2) can reach OTR ≤2, WVTR ≤1 but harms PE/PP mono-film recyclability. [5]
  6. Seals & integrity are standardized. Specify seal strength by ASTM F88; develop windows with F2029; verify integrity via F1929 (dye), F2096 (bubble), F1140 (burst). [6]
  7. Inks stick when surfaces wet. Aim for ≥38 dynes/cm on PE/PP (ASTM D2578), then qualify adhesion (ASTM D3359 or ISO 2409). Food contact relies on EU 1935/2004 & 2023/2006, EU 10/2011; US 21 CFR 175.105 (adhesives), 177.1520 (olefins), 177.1630 (PET). [7]
3–5 actions to take next
  • Lock region-specific recyclability targets early (RecyClass/OPRL/EPR state rules) and design to mono-material thresholds. [2–4]
  • Build test plans into specs: F2029 (seal window), F88 (min seal strength), F1929/F2096/F1140 (integrity), F1249 (WVTR), D3985 or F1927 (OTR). [6,8]
  • For inks/adhesives, require EuPIA GMP and retentive inks, limit print coverage where needed for film recyclability grades; verify surface energy and adhesion. [2,9]
  • Prefer EVOH ≤5% with compliant tie-layers; avoid metallisation on PE/PP mono-films. If clear barrier is needed, evaluate SiOx/AlOx (no extra primers) against RecyClass rules. [2]
  • Prepare for EPR data: material bills, mass by region, recyclability grade, and post-market fate evidence (APR/RecyClass test reports). [3]
Risks & 12–24-month watchlist
  • EU PPWR delegated acts on recyclability-at-scale & design-for-recycling grades; UK film kerbside rollout; US FTC Green Guides update; state EPR fee tables. [1,3,4,10]

2) Definitions & Concepts

  • PE / PP / PET. Polyethylene, Polypropylene, Poly(ethylene terephthalate).
  • OTR / MVTR (WVTR). Gas/vapour transmission rates under specified conditions (e.g., OTR 23 °C/50% RH; WVTR 37.8 °C/90% RH). [8]
  • SIT. Seal Initiation Temperature; lowest jaw temperature for continuous peelable seal; developed via ASTM F2029. [6]
  • Dyne level. Surface energy (dynes/cm). PE/PP typically need ≥38 dynes/cm for good adhesion (ASTM D2578). [7]
  • EVOH / PA / PVDC. Common barrier layers; recyclability depends on % and structure. [2]
  • SiOx / AlOx. Clear ceramic barriers; compatibility varies by polymer and primers. [2]
  • Retentive inks. Inks formulated to remain with the film matrix during washing/sorting to protect recyclate quality. [2]
Concept map (bullet network)
  • Structure: Substrates (PE/PP/PET) → Tie/adhesives → Seal layer → Inks/primers → Coatings/barrier.
  • Performance: Barrier (OTR/MVTR) ↔ Thickness & humidity ↔ Product shelf-life. [5,11]
  • Convertibility: Sealing window, COF, curl, shrink.
  • Compliance: FCM (EU/US), GMP (EU 2023/2006), inks (EuPIA), adhesives (21 CFR 175.105). [7]
  • Sustainability: Mono-material threshold (RecyClass/APR), EPR fees, labels (How2Recycle/OPRL). [2,3,12]

3) Standards, Regulations, and Governance

EU (priority)
  • PPWR: Regulation (EU) 2025/40 overhauls packaging rules, sets design-for-recycling and EPR harmonization, and enables recyclability grades via delegated acts. [1]
  • Food contact: EC 1935/2004; GMP 2023/2006; plastics measure EU 10/2011; inks via GMP (Swiss Ordinance practice pending EU inks measure). [7]
  • Barrier tests: ISO 15105-2 (OTR), ISO 15106-3 (WVTR) as EN/ISO adoptions. [8]
US
  • FCM rules: 21 CFR 177.1520 (olefins), 177.1630 (PET), 175.105 (adhesives). [7]
  • FTC Green Guides: 2012 edition in force; revision underway (watch recyclability/recycled content). [10]
  • State EPR: Maine, Oregon, Colorado, California progressing producer registration, reporting, and fees. [3]
UK
  • Plastic Packaging Tax: £223.69/tonne from 1 Apr 2025 for <30% PCR. [4]
  • OPRL & Simpler Recycling: Kerbside films by 31 Mar 2027; spec PE/PP films to be kerbside-ready. [4]
What differs by region (snapshot)
TopicEUUSUK
Core lawPPWR (Reg. 2025/40)21 CFR FCM; state EPRPPT + Simpler Recycling
Recyclability criteriaHarmonized via PPWR delegated acts; gradedAPR Design Guide & How2RecycleOPRL criteria; kerbside films 2027
LabelsEU-wide PPWR labellingHow2Recycle (voluntary, evidence-based)OPRL binary labels

Evidence gap: PPWR delegated-act details on grading thresholds/test methods are pending; treat 2025–2027 as a transition period. [1]

4) Evidence Base & Benchmarks

Barrier benchmarks (indicative, common spec conditions)
Film (thickness)OTR @23 °C/50%RHWVTR @37.8 °C/90%RHNotes
BOPP, plain (20 µm)2000–2500 cc/m²·d4–7 g/m²·dTypical snack wrapper core. [5]
PET, plain (12 µm)100–15040–50High stiffness, printable. [5]
PET, metallized (OD≈2.2)≤2≤1Excellent barrier; recyclability issues in PE/PP streams. [5]
EVOH coex layer (~29 µm)~1–1.5~4.5Barrier collapses with humidity; select grade/ratio carefully. [5,11]
Humidity effect on EVOH

EVOH barrier degrades as RH increases; lower-ethylene grades retain better barrier at normal humidity. Use supplier curves when sizing layer thickness and % of total. [11]

Test methods (select)
  • OTR: ASTM D3985 (coulometric), ASTM F1927, ISO 15105-2. [8]
  • WVTR: ASTM F1249, ISO 15106-3 (ASTM E96 not equivalent for thin films under packaging conditions). [8]

Evidence gap: LDPE/LLDPE OTR/MVTR vary widely by density/crystallinity/gauge; use current supplier datasheets at your thickness and conditioning.

5) Design & Production Implications

Rules of thumb (with standards)
  • Seal design: Build a seal window with ASTM F2029; specify minimum seal strength by ASTM F88 (method/jaw/rate) and validate integrity via F1929/F2096/F1140. mLLDPE/EVA lower SIT and widen the window; check recyclability of ionomers in PE streams. [6,9]
  • Ink adhesion & surface prep: Target ≥38 dynes/cm on PE/PP (ASTM D2578). Qualify adhesion with ASTM D3359 or ISO 2409; require EuPIA GMP inks; use retentive inks and manage print coverage per film recyclability guides. [7,2,9]
  • Barrier selection: Prefer SiOx/AlOx on PP or EVOH ≤5% with compliant tie-layers for polyolefin mono-films; avoid metallisation and PVDC for top recyclability classes. [2]
  • Adhesives/lamination: Keep adhesive % within guide limits (e.g., ≤2.5% on PE for full compatibility); for FCM, follow 21 CFR 175.105 and ensure functional barriers. [2,7]
Material/format trade-offs (qualitative)
  • Mono-PE: Excellent sealability, decent MVTR, weak OTR → add EVOH ≤5% or external barrier web (recyclability trade-off). [2,5]
  • Mono-PP: Stiffer, clearer, higher SIT; SiOx/AlOx options exist; check PP film rules. [2]
  • PET-based laminates: Great stiffness/print but not mono-polyolefin; harder to recycle in film streams; rely on bottle systems. [2,12]
Manufacturability flags
  • Specify thickness tolerances, COF, and jaw pressure/temperature/time; note OTR/MVTR drift with humidity and orientation. [8,11]
Converter/OEM expectations

Provide ink/adhesive laydown, target dyne, max web temp, seal jaw spec, and test methods in RFQs. Many OEMs require F88 seal strength targets and D2578 dyne verification on incoming film. [6,7]

6) Sustainability & Compliance Considerations

Recyclability guidance (design time)
  • RecyClass PE/PP Films (EU): ≥95% main polymer for class A; EVOH ≤5% and tie-layer ratio control; metallisation non-compatible; water-releasable label adhesives <40 °C; retentive inks. [2]
  • APR (US): Use APR Design Guide and PE Film Critical Guidance tests when claiming Store Drop-Off; How2Recycle aligns protocols. [12]
  • OPRL (UK): Plan for kerbside film collection by 2027; follow WRAP/OPRL guidance for material choices. [4]
EPR implications & substantiation
  • EU: expect modulated fees tied to recyclability grade under PPWR. [1]
  • US: PROs (e.g., Circular Action Alliance) administering registration, reporting, fees (Oregon changes 2025; Colorado plan approvals 2025). [3]
  • UK: PPT cost lever + EPR labelling timelines; collect evidence (specs, test reports, recyclability letters) per SKU. [4]

Claims risk: Substantiate “recyclable/recycled content/plastic-free” with current rules (FTC Green Guides update pending; PPWR labelling to define formats). [1,10]

7) Workflow & Tooling (ready to adapt into PDA tools)

Checklists (abbreviated)
  • Print-ready & pre-press: Film ID & thickness; target dyne (≥38 PE/PP) [D2578]; primer/topcoat; ink system & EuPIA GMP; print coverage vs recyclability; color density; trapping; registration; proof substrate match. [7,2,9]
  • Seal & integrity: Jaw T/P/t; SIT scan (F2029); strength spec (F88—method/jaw/rate); integrity test (F1929/F2096/F1140); aging/retest. [6]
  • Recyclability: % polymer by weight; barrier type & %; adhesive %; label/closure; ink type & coverage; guideline cross-check (RecyClass/APR/OPRL). [2,12]
Decision trees (examples)
  • PE pouch labels: PE facestock → water-releasable adhesive (<40 °C) → retentive inks → density <0.97 g/cm³ → RecyClass PE A/B? [2]
  • Barrier for salty/oily snack: Start BOPP//mPE → add SiOx BOPP or thin EVOH (≤5%) depending on shelf-life → check metallisation trade-off vs recyclability grade. [2,5]
Calculator blueprints
  1. Laminate OTR (series layers): Ri = Li / Pi; Rtot = ΣRi; Permeance = 1/Rtot; OTR = Permeance × Δp. Inputs: layer thickness Li, permeability Pi (match temp/RH); humidity-adjust PEVOH(RH). Outputs: OTR_total; RH sensitivity. [8,11]
  2. Seal window capture: Temperature sweep → response surface for F88 strength vs T/time/pressure; fit to select nominal & limits. [6]
  3. PPT cost (UK): If PCR <30%, Cost = mass(t) × £223.69/t (2025/26). [4]
Template specs (RFQ pack)
  • SKU, net content, target shelf-life; structure (layers % & µm); barrier targets (OTR/MVTR @ method/conditions); seal window; test methods; dyne target & verification; ink system & coverage; recyclability conformance & targeted grade; EPR/PPT attributes.

8) Category-Specific Guidance

Beauty/Personal Care. Aroma-sensitive: prefer clear barrier SiOx/AlOx over metallisation to preserve PP mono-material eligibility; check fragrance migration; ensure retentive inks. [2]
Food. Dry/crispy: WVTR dominates—BOPP platforms; metallized PET common but consider SiOx BOPP or EVOH where recyclability grades matter. High-fat or retorted: PET/foil structures—accept recyclability compromises or redesign system; validate seals/integrity rigorously. [5,2,6]
Beverage (sachets, sticks). Small formats <30 cm² can be penalized for sorting; design to exceed thresholds and keep polyolefin purity. [2]

9) Case Studies (Problem → Approach → Result)

1) Snack pouch wants “recyclable”
Problem: Metallized OPP//PE triplex fails PE-film recyclability.
Approach: Replace MET-OPP with SiOx-BOPP and keep total EVOH ≤5%; use water-releasable labels and retentive inks; adhesive ≤2.5%.
Result: Achieved PE/PP film compatibility per RecyClass (class depends on % and features) with barrier on par with metallized. [2]
2) Kerbside-ready in UK by 2027
Problem: Brand roadmap requires OPRL “Recycle” as films become kerbside.
Approach: Mono-PE with EVOH barrier (≤5%) and compliant tie-layer ratio; plan for OPRL guidance & Simpler Recycling dates.
Result: Future-proofed structure and labelling plan; PPT exposure reduced via increased PCR in rigids. [4,2]
3) US multi-state rollout under EPR
Problem: Inconsistent recyclability claims across ME/OR/CO/CA.
Approach: Align to APR Design Guide; run Critical Guidance tests for PE films; register with PROs; standardize evidence files.
Result: Reduced compliance risk and smoother access as Oregon changes start 2025 and others phase in. [12,3]

10) Common Pitfalls & Red Flags

  1. Calling metallized polyolefin film “recyclable” in EU/UK streams—non-compatible for PE/PP mono-film grades. [2]
  2. EVOH >5% or incorrect EVOH:tie-layer ratio. [2]
  3. Using non-releasable label adhesives on films. [2]
  4. Omitting method/conditions on OTR/MVTR targets. [8]
  5. Printing on low-dyne film; skipping ASTM D2578 verification. [7]
  6. Setting seal specs without ASTM references—hard to audit. [6]
  7. Assuming US rules are static—state EPR is changing labelling/procurement rapidly. [3]

15) References

Primary sources include PPWR (Reg. 2025/40), RecyClass PE/PP film guidelines (July 2025), US state EPR statutes and PRO guidance, UK PPT/OPRL/Simpler Recycling, barrier benchmarks (supplier literature), ASTM F88/F2029/F1929/F2096/F1140, ASTM F1249/D3985/F1927, ISO 15105-2/15106-3, EuPIA GMP, APR Design® Guide & Critical Guidance for PE films, and EVOH humidity dependence literature. See numbered citations [1]–[12].

Designer tip / Compliance watch / Manufacturing note

  • Designer tip: Start with numbers: shelf-life → OTR/MVTR → barrier selection → % by weight vs RecyClass/APR → tie-layer ratio → then lock top-web/inks.
  • Compliance watch: Don’t assume metallized film claims; use SiOx/AlOx or EVOH ≤5% where possible and document. [2]
  • Manufacturing note: Always state method & conditions next to targets (e.g., “OTR ≤ 10 cc/m²·d @23 °C/50%RH by ASTM F1927”).
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