INZEA FH11S Flexible 40% Bio-Based Retail Bag Film Polylactic Acid is a compounded polylactic acid resin modified for thin-gauge blown film in retail bag formats. The grade designation carries a stated bio-based carbon content of 40% when measured according to EN 16640 or ASTM D6866. The material is positioned between unplasticized PLA and fossil-derived low-density polyethylene, with flexibility introduced through a non-disclosed modifier system. Because the product name identifies bio-based carbon rather than full polymer composition, converter evaluations must separate renewable content from end-of-life certification; a 40% bio-based carbon value does not by itself establish industrial compostability under EN 13432.

Publicly available single-point datasheets for this grade are limited; extrusion trials should therefore generate values under ISO 527-3 for tensile properties, ISO 6383-2 for trouser tear, and ISO 1133-1:2022 for melt mass-flow rate. Comparative positioning is drawn from the broader class of flexible PLA film compounds and from downstream converting practice rather than from a certified FH11S datasheet.

Why does bubble stability govern gauge uniformity in PLA-based retail film?

Blown film conversion of flexible PLA compounds requires a low-shear single-screw extruder with 24:1 to 30:1 L/D and a compression ratio of 2.5:1 to 3.5:1. Barrel temperatures from feed to die are typically set between 150°C and 180°C, and melt temperature is held below 190°C to limit lactide reformation and molecular weight loss. A reverse temperature profile is used from feed to metering to prevent bridging of low-melting modifiers; a typical profile is 145°C feed, 160°C compression, 170°C metering, and 175°C die. The die gap is widened to 0.8 mm to 1.2 mm, compared with 0.5 mm to 0.8 mm for low-density polyethylene, to reduce shear heating and preserve melt strength. Blow-up ratio is limited to 2:1 to 3:1 because PLA-based melts exhibit lower extensional viscosity than LDPE. Frost line height is maintained at 1 to 2 die diameters using chilled air at 10°C to 20°C to stabilise bubble geometry. Melt pressure at the screen pack should remain below 250 bar; a 60/80/60 mesh pack is commonly used to trap gels without excessive backpressure. Grooved-feed extruders designed for polyolefins increase screw torque and melt temperature; use without supplier validation is not recommended.

At shear rates of 100 s⁻¹ to 500 s⁻¹, flexible PLA compounds typically show apparent viscosity of 300 Pa·s to 800 Pa·s at 190°C, while LDPE often shows 800 Pa·s to 1500 Pa·s. The lower viscosity reduces screw pressure but also reduces bubble stability. Extensional viscosity data for this grade are not widely published; however, bubble instability is observed when draw-down ratio exceeds 5:1 or when frost line height exceeds 2 die diameters. Suppliers often recommend adding 0.5% to 2% of a PLA-compatible melt-strength modifier in high-BUR operations, but this must be validated for food contact if used.

Predrying is performed in a desiccant wheel dryer with dew point ≤ -40°C and inlet air temperature of 65°C to 75°C for 4 h to 6 h. Residual moisture must be reduced below 250 ppm before extrusion. Hydrolysis of the polyester backbone occurs at higher moisture loadings, producing a measurable drop in melt viscosity, film haze, and gel formation. The hopper should be blanketed with dry air or nitrogen when ambient relative humidity exceeds 60%.

Film property targets for flexible PLA grades of this configuration typically fall within a tensile strength range of 25 MPa to 45 MPa and elongation at break of 100% to 300% under ISO 527-3 at 23°C and 50% relative humidity. Trouser tear resistance under ISO 6383-2 is lower than LDPE but higher than unmodified PLA film; the exact value depends on modifier type and loading. Seal initiation temperature is commonly 80°C to 95°C for flexible PLA-based compounds, which places the material below LDPE but within the operating range of rotary and impulse sealers. Static and dynamic coefficients of friction require slip and antiblock masterbatch adjustment during film production; corona treatment to at least 38 mN/m is required for water-based flexographic ink adhesion.

Unlike PBAT-rich films, the product may require corona treatment and antistatic addition because PLA has higher surface resistivity than PBAT. Static charge retention can cause bubble collapse and poor layflat. A surface resistivity below 10¹¹ Ω/sq according to IEC 61340-2-3 is often targeted for high-speed bag conversion.

Oxygen transmission rate for PLA-based film is moderate under dry conditions but humidity-sensitive. At 23°C and 0% RH, OTR is commonly 300–600 cm³/m²·day·bar at 25 µm; at 80% RH, the value can increase by a factor of 2 to 3. This limits use in modified-atmosphere packaging unless a barrier coating or lamination is added. Published data for this specific configuration is limited.

Comparative Profile Against PBAT, LDPE, and Rigid PLA Film

INZEA FH11S occupies an intermediate position between unplasticized PLA and PBAT-based compounds. Relative to standard PLA film, the flexible grade trades modulus and oxygen barrier for increased elongation and lower seal initiation. Relative to fossil LDPE, the grade raises renewable carbon but lowers heat resistance and moisture barrier; water vapour transmission of PLA-based films is generally one to two orders of magnitude higher than LDPE at equivalent thickness. Relative to PBAT/PLA blends, FH11S specifies 40% bio-based carbon but may require the same industrial compostability testing if the film is marketed as compostable. The product is not a drop-in replacement for LDPE on the same extrusion line because lower melt strength reduces maximum line speed and BUR.

Regulatory compliance for retail bag film in food contact requires confirmation that the final compounded product meets FDA 21 CFR 175.300 or EU Regulation (EU) No 10/2011 with simulant-specific migration limits. INZEA FH11S is not a standard polyolefin resin; converters must verify that the plasticizer, nucleating agent, and slip/antiblock additives are covered by positive lists. For industrial composting destinations, bio-based carbon content alone is not a certification. EN 13432 requires ≥ 90% biodegradation by ISO 14855-1 within 180 days, disintegration, and ecotoxicity testing. The 40% bio-based carbon designation should be reported separately from compostability claims to avoid greenwashing.

When Downstream Bag-Making Equipment Exposes Thermal and Edge Limitations

Downstream conversion on high-speed bag machines imposes constraints that are not present in film production. INZEA FH11S film exhibits lower heat resistance than LDPE, so sealing jaws and hot knives must be profiled to avoid film puckering above 60°C. Hot-wire cutter settings should be reduced by 15°C to 25°C relative to LDPE settings because PLA-based films have a lower melting point and a narrower thermal sealing range. Intermittent sealing dwell times of 0.3 s to 0.8 s are usually adequate, but seal strength should be verified under ASTM F88/F88M after 24 h ageing because PLA-based seal strength can decline with post-seal crystallisation. Slitting should use razor blades maintained at low cut pressure; dull blades initiate machine-direction tears along oriented crystalline regions.

Storage of pellets and finished roll stock should be in sealed moisture-barrier packaging at 15°C to 25°C and relative humidity below 50%. Opened pellet containers should be used within 8 h when ambient dew point exceeds 10°C. Roll stock should be conditioned at 20°C to 23°C for 24 h before printing to prevent dimensional change from moisture uptake. The film is not recommended for direct contact with high-acid foods above 40°C without migration testing under the intended food simulant.