Model designation Kebacomp FE 120204 defines a barrier-modified polylactic acid film grade compounded for blown film and cast film conversion in monolayer and fully compostable coextruded structures. The grade is supplied as pelletized feedstock; pellet dimensions, bulk density, and residual moisture are controlled and reported on the lot certificate of analysis. The melt phase is based on polylactic acid synthesized from lactide, with a glass transition temperature in the range of 55–60 °C and a crystalline melting endotherm between 145 °C and 175 °C when measured by differential scanning calorimetry in accordance with ISO 11357-2. Unlike conventional barrier films that combine PLA with EVOH, PVDC, or metallized substrates, FE 120204 is formulated to deliver barrier functionality without introducing non-compostable layers at the film converter. The product is intended for flexible packaging applications where industrial compostability must be demonstrated to EN 13432:2000 or ASTM D6400-21 and where oxygen, aroma, moisture, or mineral oil transfer must be reduced relative to unmodified PLA.

The role of FE 120204 in a film structure is best understood against unmodified PLA and PBAT-rich compostable blends. PLA film grades typically exhibit tensile modulus values of 2500 MPa to 4000 MPa and elongation at break below 20 % when tested to ISO 527-3; PBAT-rich films are generally below 120 MPa with elongation at break above 300 %. FE 120204 maintains a PLA-continuous matrix, giving higher stiffness and dimensional stability than PBAT-dominated compostable films. The trade-off is a more limited elongation window and a higher minimum forming temperature, which places the grade in flow-wrap, stand-up pouch web, lidding film, and label facestock rather than stretch wrap or heavily gusseted bags. The barrier modification is achieved through increased tortuosity in the diffusion path, not through polyethylene-based tie layers; as a result, laminate structures remain compatible with industrial composting standards only if the ink, adhesive, and surface coatings also meet EN 13432:2000 requirements.

Barrier improvement in PLA is generally obtained by increasing the tortuosity of the permeable phase and reducing free volume. High-aspect-ratio platelet additives dispersed in the PLA matrix can reduce the effective diffusion coefficient by a factor of 2 to 10 when exfoliation is adequate and platelets have an aspect ratio above 50. Dispersion quality is assessed by X-ray diffraction and scanning electron microscopy of cryo-fractured film. Poor dispersion leads to pinhole formation and unchanged oxygen transmission rate despite higher additive loading. The specific additive system in FE 120204 is proprietary and not disclosed in this document; therefore, no stoichiometric ratio or exact platelet aspect ratio is provided. Published data for this specific configuration is limited.

What prevents the barrier modification from suppressing compostability?

The compostability of a barrier-modified PLA film is not inferred from the base resin alone; it is established for the complete formulation and converted film. EN 13432:2000 requires that aerobic biodegradation of the film or its organic constituents reaches at least 90 % relative to a positive reference within 180 days in a controlled composting test conducted according to ISO 14855-1. Disintegration after 12 weeks in a pilot-scale compost must leave no more than 10 % of the original dry mass on a 2.0 mm sieve when tested to ISO 16929:2021. Ecotoxicity is assessed by plant germination and biomass tests in EN 13432:2000 Annex E, and heavy metals are limited by the compostability standard. For the United States market, ASTM D6400-21 specifies similar requirements for biodegradation, disintegration, and ecotoxicity. The barrier system in FE 120204 must therefore avoid additives that inhibit microbial activity or exceed the allowable inert fraction. Each converted film stack should be retested after printing and lamination because inks and adhesives can alter disintegration behavior.

Before film extrusion, the pellets are dried in a desiccant bed or hopper dryer to a residual moisture level below 250 ppm as verified by ISO 15512:2019. The recommended drying condition is 70–80 °C for at least 4 h with supply air at a dew point at or below -40 °C. In PLA, moisture above 0.025 % by mass at melt temperatures above 190 °C accelerates hydrolysis, causing melt flow index drift, lactide generation, and bubble instability. On a production-scale blown-film line using a 45 mm screw with an L/D ratio of 30:1 and a 1.0 mm die gap, stable operation is typically obtained at a melt temperature between 180 °C and 205 °C, a blow-up ratio of 2.0:1 to 3.5:1, and a frost line height of 250 mm to 350 mm above the die. Screw speed is adjusted to maintain an extruder head pressure below 350 bar; torque should not exceed 85 % of the drive rating. Cast film trials on a 25 mm cast line with a 0.5 mm die gap commonly use chill roll temperatures between 15 °C and 30 °C and an air gap of 10 mm to 20 mm. Edge tear and thickness bands above ±5 % variation have been observed when take-off ratio exceeds 8:1 or when melt temperature falls below 170 °C due to incomplete melting and high melt viscosity. These limits are class-level for PLA-based film grades; product-specific processing windows for FE 120204 should be taken from the manufacturer’s lot card.

Regrind use must be controlled because PLA is susceptible to molecular weight reduction during drying and extrusion, and flake surface area is larger than that of virgin pellets. In blown-film production, regrind addition above 20 % by weight may reduce melt strength and bubble stability; a melt flow rate increase of 1.0 g/10 min to 2.0 g/10 min at 190 °C/2.16 kg is often accompanied by a decrease in tear resistance and an increase in gel particles when the flake is contaminated with dust or moisture. A dried regrind fraction can be used at up to 20 % if the flake is ground to a uniform size below 8 mm and blended before drying. Inline melt pressure and bubble diameter fluctuation should be recorded to establish the boundary for a specific line.

Corona treatment improves ink adhesion and lamination bond strength. PLA-based film surfaces are typically treated to 42–48 dyn/cm when measured by ASTM D2578. Treatment levels above 50 dyn/cm may embrittle the surface and increase extractable oligomer content. The target treatment window should be verified for the specific electrode type, line speed, and film thickness. After corona treatment, the film should be wound with controlled tension to avoid blocking and telescoping.

When oxygen transmission rate falls below 10 cm³/(m²·day·atm), coulometric sensor verification is required

Oxygen transmission rate is measured according to ASTM D3985-17 or ISO 15105-2 at 23 °C and a defined relative humidity. Unmodified PLA film at 25 µm commonly exhibits OTR in the range of 30–60 cm³/(m²·day·atm) at 0 % RH; at 80 % RH, oxygen flux increases because water plasticizes the PLA matrix, and comparison must be made under identical humidity because OTR ranking can invert between dry and humid conditions. FE 120204 is formulated to reduce OTR relative to unmodified PLA at equal thickness and humidity; the exact certified value is supplied on the lot certificate of analysis and is not reproduced here. Measurements below 10 cm³/(m²·day·atm) require linearity verification using a certified film reference standard because edge leakage and sensor background current often exceed the reported film flux at this level. The test cell should be masked to a defined test area, and the downstream oxygen sensor is calibrated with a standard gas mixture traceable to a national metrology institute.

Water vapour transmission rate is measured per ASTM F1249-20 or ISO 15106-2 at 38 °C and 90 % RH. Unmodified PLA at 25 µm is typically reported between 150 and 300 g/(m²·day). The barrier system in FE 120204 is intended to reduce WVTR but does not approach the moisture barrier of a 25 µm LDPE or oriented PP film; converters should not specify this grade where a WVTR below 20 g/(m²·day) at 38 °C/90 % RH is required unless a downstream coating or laminate layer is added. Heat seal initiation temperature and seal strength are measured under ASTM F88/F88M-21 with dwell time, jaw temperature, and sealing pressure reported in the test certificate. PLA-based films usually require seal jaw temperatures 10–20 °C above the film surface melting onset; excessive jaw temperatures above 160 °C can cause shrinkage, sticking, or loss of opacity.

Regulatory Documentation, Food Contact, and Storage Limits

Storage conditions for PLA-based compounds are determined by the glass transition temperature and hydrolysis sensitivity. Bags should be kept in a cool, dry warehouse at or below 30 °C and below 60 % RH. If the pellet moisture exceeds 400 ppm after storage, drying at 70–80 °C for 4–6 h is required before melt processing; drying above 90 °C can cause pellet agglomeration and must be avoided. The food-contact status of FE 120204 must be verified against the supplier’s Declaration of Compliance for EU Regulation 10/2011 and, where relevant, FDA 21 CFR food-contact regulations. Overall migration testing of the converted film is performed according to EN 1186-1:2002 with food simulants selected under EU Regulation 10/2011; typical simulants for aqueous, acidic, and fatty foods are 10 % ethanol, 3 % acetic acid, and 95 % ethanol or isooctane as appropriate for the intended use. The converter is responsible for verifying that printing inks, laminating adhesives, and any added slip or antiblock masterbatch do not violate the compostability or migration limits of the final package.