Ecomp 180 is a compounded polylactic acid (PLA) formulation for blown and cast film. The grade is evaluated in downstream conversion by three coupled properties: melt strength at low moisture, heat-seal initiation temperature, and disintegration velocity under industrial composting. These properties determine whether a converter can run high-speed side-weld bag machines or must reduce line speed to avoid gauge bands and tear propagation failures. The scenarios that follow are limited to commercially active downstream segments for compostable film; they do not include rigid thermoforming, injection moulding, or foam extrusion, where the melt rheology of this compound is not technically suitable. The melt temperature window is bounded by PLA shear sensitivity: below 175°C, unmelted gel particles appear; above 220°C, molecular weight reduction becomes visible as a die-pressure drop and an MFR increase under ISO 1133-1:2022 Method A. Batch-to-batch MFR variation of 2 g/10 min can shift frost line position by 0.5 die diameters on high blow-up-ratio lines. Processing data are drawn from EN 13432:2000, ASTM D6400-23, ISO 14855-1:2012, ISO 1133-1:2022, ASTM D882-18, ASTM D1922-23, EN 17033:2018, and manufacturer technical bulletins covering L/D 32:1–44:1 extruders.

Compostable Produce and Fresh-Cut Packaging Films

Compliance for this segment is bifurcated: compostability certification under EN 13432:2000 Clause 7 or ASTM D6400-23 requires ≥90% mineralization within 180 days under ISO 14855-1:2012 controlled composting, plus ecotoxicity screening under OECD 208; food-contact verification under Regulation (EU) No 10/2011 requires overall migration below 10 mg/dm² and specific migration limits for PLA monomers, stabilizers, and slip agents. Because this segment prioritizes clarity and stiffness over tear propagation, the compound is introduced at 100 wt% on monolayer cast film lines below 40 µm. On blown film equipment, 70–90 wt% Ecomp 180 blended with 10–30 wt% of a certified compostable copolyester is used; below 10 wt% copolymer addition, transverse-direction Elmendorf tear resistance seldom exceeds 15 N/mm, and side-seal failures increase on automatic bagging equipment. A 1–3 wt% silica antiblock masterbatch is added only when film-to-film blocking on reels exceeds 40 g/cm under ASTM D3354-15 parallel-plate testing.

Cast film extrusion on a 32:1–42:1 L/D single-screw or co-rotating twin-screw machine uses a melt temperature of 185–210°C, adapter 200°C, flat die lip gap 0.4–0.8 mm, and a chrome-plated chill roll at 15–25°C. Pre-drying at 80°C for 4 h to a dew point of -40°C or residual moisture below 250 ppm is mandatory; moisture-induced hydrolysis at the die lip produces plate-out and film hazing. On blown film lines, a die gap of 1.2–1.8 mm, blow-up ratio 2.5:1–3.5:1, and frost line height of 2–4 die diameters maintain bubble stability. Corona treatment is set to 38–42 dyn/cm for water-based flexographic inks. Terminal products include perforated misting bags, unprinted produce roll-stock, wedge-shaped fresh-cut salad bags, and bakery bread bags; perforation is applied after gauge with hot-needle or laser perforators at 0.3–0.8 mm hole diameter.

Why Do Certified Checkout Bag Films Tear at Side-Seal Junctions Under High-Speed Conversion?

EN 13432:2000 and ASTM D6400-23 certification do not directly measure side-seal tear propagation, but mechanical acceptance tests for this segment use ASTM D882-18 tensile properties and ASTM D1922-23 Elmendorf tear. When the compound is run neat, machine-direction tensile strength at break is typically 35–55 MPa, while transverse tear remains below 15 N/mm; adding a certified compostable copolyester at 15–25 wt% raises transverse tear to 20–35 N/mm but reduces modulus by 30–50%. The film formulation therefore uses 75–85 wt% Ecomp 180, 15–25 wt% additional copolyester, and 0.5–1.5 wt% slip/antiblock masterbatch. Heat-seal initiation temperature is another boundary: PLA-rich film begins sealing at 95–110°C, and side-seal jaw temperature above 150°C causes sticking to the jaw and film puckering.

Blown film conversion on a 32:1–40:1 L/D extruder with internal bubble cooling uses die diameter 100–200 mm, die gap 1.4–2.2 mm, BUR 2.8:1–3.2:1, frost line 2–3 die diameters, and melt temperature 185–205°C. Pre-drying conditions are 80°C for 4–6 h at dew point -40°C; moisture above 300 ppm creates micro-bubbles and surging. The bubble is collapsed with gusseting rolls, slit in line, and transferred to a side-weld bag machine running 80–140 cycles/min. At these speeds, two failure modes dominate: angle tears at the gusset seal junction and intermittent seal leaks caused by temperature variation across the seal bar. Seal bar temperature is set 120–145°C with dwell 0.4–0.8 s, and Teflon-coated seal bars are used to reduce sticking. Operating boundary: amine-based slip agents should not be combined because reactive amines accelerate PLA hydrolysis in the presence of residual moisture; only non-amine, vegetable-based slip packages are compatible. Terminal products include T-shirt checkout bags, die-cut handle merchandise bags, block-header bags, and organic waste bin liners; die-cut handle versions require a 5–10 wt% addition of a branched compostable copolyester to resist die-cut edge propagation.

Black and white-black agricultural mulch film produced from Ecomp 180 is governed less by retail optics and more by EN 17033:2018, which sets a soil degradation period of maximum 24 months, fragmentation and ecotoxicity limits, and heavy-metal thresholds under OECD 208 germination testing. The formulation for black mulch uses 96–98 wt% Ecomp 180 with 2–4 wt% carbon black masterbatch; white-black coextruded mulch uses the same black core and a pigmented white skin at 8–15% of total thickness. The carbon black loading is not cosmetic: it must remain above 2 wt% to prevent UV embrittlement below 120 kWh/m² UV-A exposure, but above 4 wt% it raises melt viscosity and creates die lines in 15–20 µm film. Published data for white-black coextruded Ecomp 180 field degradation under tropical conditions is limited; converters should validate via EN 17033:2018 field trials.

Cast extrusion for agricultural film runs melt temperature 190–215°C with die lip gap 0.5–0.9 mm and chill roll 18–28°C; blown lines use die gap 1.6–2.2 mm, BUR 2.0:1–2.8:1, and a low frost line to maintain transverse gauge uniformity. Mechanical puncture resistance is tested under EN 14477:2004; a 15 µm black mulch film typically requires a puncture force above 3 N. The film is laid on soil with a tractor-mounted mulch layer. Terminal products include 12-month black mulch, white-black dual-layer mulch, and perforated nursery ground film. After the growing season, the film is incorporated into the top 15–20 cm of soil; disintegration under EN 17033:2018 requires ≥90% fragmentation to <2 mm within 24 months. This segment has a processing boundary: PLA-rich film stored in hot, humid warehouses above 35°C and 70% RH can begin hydrolytic embrittlement before installation.

When Cast Film Is Drawn to 20 µm Without Draw Resonance

Dry food pouches and lamination webs made from Ecomp 180 are converted on high-speed cast film lines where gauge reduction to 20 µm is possible only when draw resonance is suppressed by a small air knife at the die exit and a low melt temperature. Under the EU food-contact framework, the film must comply with Regulation (EU) No 10/2011 with overall migration below 10 mg/dm²; if the finished pouch carries the Seedling logo, EN 13432:2000 disintegration and ecotoxicity criteria apply to the final multilayer structure. The compound is used at 90–100 wt% with 0–10 wt% of a compostable copolyester for seal-layer modification; slip and antiblock masterbatch loading is 0.5–1.0 wt%. For lamination to paper or other compostable substrates, a solventless adhesive certified under EN 13432:2000 is used at 1.5–2.5 g/m²; solvent-based adhesives are incompatibility points because residual solvent can trigger haze and seal contamination.

On a 38:1 L/D cast line with a 1500 mm die, melt temperature is 185–205°C, die gap 0.45–0.7 mm, chill roll 18–24°C, and line speed 120–250 m/min. Draw resonance is controlled by positioning the air knife at 5–10 mm from the die lip with air velocity 30–60 m/s; moisture must be below 250 ppm. The edge trim is recycled at up to 15 wt%, but higher regrind levels increase gel counts and cause optical defects in the seal area. Terminal products include dry food pillow pouches, compostable coffee overwrap, inner bags for cereal cartons, and lamination film for paper-based pouches. Heat-seal strength under ASTM F88/88M-21 is the critical in-process test, with a minimum seal strength of 4 N/15 mm required before flexographic printing.

Non-food flexible mailer film is a growing conversion route for Ecomp 180 because the application does not trigger direct food-contact testing but still requires the full organic-recovery documentation under EN 13432:2000 or ASTM D6400-23. The film is formulated at 100 wt% Ecomp 180 for stiff, opaque mailers, or 75–85 wt% with 15–25 wt% biodegradable copolyester for puncture-resistant mailing envelopes. Opacification uses 2–4 wt% titanium dioxide masterbatch; a 1–2 wt% slip/antiblock package reduces mandrel release torque during film winding. Mechanical acceptance follows ASTM D882-18 for tensile, ASTM D1922-23 for tear, and ASTM D1709-16A for dart impact; because PLA-rich film has a lower dart impact than LDPE, the minimum dart impact of 250 g for heavy mailers is achieved through the copolyester blend rather than by gauge increase alone.

Blown film extrusion uses die gap 1.6–2.2 mm, BUR 2.5:1–3.0:1, frost line 2–4 die diameters, and melt temperature 185–205°C; the web is gusseted and surface-printed with water-based inks after corona treatment to 38–42 dyn/cm. Bag conversion on a bottom-seal or side-seal line runs 60–100 cycles/min with heat-seal jaw temperature 120–145°C and dwell 0.5–0.8 s. Terminal products include e-commerce mailing envelopes, garment bags, disposable shoe bags, and compostable returns mailers. A processing limitation is static charge: PLA film at line speed above 80 m/min can retain surface charge above 15 kV, so an anti-static additive at 0.5–1.0 wt% or ionizing bar is required to prevent bag mis-stacking.