Braskem LL6802N is a butene-copolymer linear low-density polyethylene blown film extrusion grade with a published nominal density of 0.918 g/cm³ and a melt index of 1.0 g/10 min determined at 190 °C/2.16 kg under ASTM D1238. Direct food-contact monolayer packaging built on this resin is converted at melt temperatures of 190–220 °C through a grooved-feed single-screw extruder with 24:1–30:1 L/D, a die gap of 1.2–1.8 mm, and a blow-up ratio of 2.0:1–3.0:1. The regulatory basis for this use is FDA 21 CFR 177.1520(c) for olefin polymers in direct contact with food and Regulation (EU) No 10/2011, under which the overall migration limit is 10 mg/dm² for general food simulants; finished film migration testing is conducted according to EN 1186-1:2002 after the converter declares the complete additive package. Formulation practice on production lines uses 100% LL6802N or a blend containing 10–30 wt% LDPE to stabilize the bubble at high frost line settings, with anti-block concentrate dosed at 0.5–1.5 wt% and erucamide slip concentrate dosed to provide 500–1200 ppm active erucamide in the final film. The downstream process includes a barrier screw with a Maddock mixing section and an air-cooled collapsing frame, producing pillow pouches, wicketed bread bags, cereal box liners, and produce transport films. The operational boundary is that raising the die gap above 2.2 mm on a single-lip air ring can allow bubble drift because of the low melt strength of butene LLDPE; anti-block below 0.5 wt% causes blocking at the surface winder.

Why does frozen-food packaging convert LL6802N at higher blow-up ratios than ambient dry-goods film?

At frozen-food gauges below 50 µm, converters run LL6802N at blow-up ratios higher than those used for ambient snack packaging to increase lateral processability and balance machine-direction tear. The conversion difference is driven by low-temperature dart impact and by the need to suppress film splitting at seal corners when packs are frozen to -18 °C or below. The regulatory basis remains FDA 21 CFR 177.1520(c) and Regulation (EU) No 10/2011, but the test plan adds cold-conditioned mechanical testing under ASTM D1709 Method A and ASTM D1922 tear-propagation testing after conditioning according to the converter's distribution temperature profile. Because no harmonized frozen-food film standard exists, the converter's specification is the primary qualification document. In three-layer coextruded structures, LL6802N is dosed at 55–70 wt% of the total film through the skin layers, while EVA at 5–10 wt%, tie resin at 5–10 wt%, and polyamide or EVOH barrier at 5–8 wt% complete the structure. The production line uses a die gap of 1.5–2.0 mm, a blow-up ratio of 2.2:1–3.0:1, melt temperature of 190–210 °C, and internal bubble cooling, with frost line height maintained at 8–12 times the die diameter. Terminal product types include frozen vegetable bags, seafood pouches, ice bag film, and frozen meat overwrap. The operational boundary is that film dart impact measured at 23 °C does not reliably predict -20 °C seal-area fracture; production qualification must include cold-room drop tests on filled packs rather than relying only on ASTM film tests.

For silage bale wrap, LL6802N is used as the base resin rather than as a minority blend component because its tear propagation resistance after repeated bale expansion compensates for lower tack in butene-copolymer LLDPE; surface tack is then supplied by VLDPE or EVA modifiers. Where the film is placed on the EU agricultural market, declarations of conformity conventionally reference EN 13207, while weathering stability is screened under ISO 4892-2 accelerated xenon-arc exposure against a converter-defined ΔE limit rather than a universal endurance target. Formulation on production lines typically starts with 75–85 wt% LL6802N, 10–20 wt% VLDPE or EVA, 3–5 wt% UV masterbatch, and 1–3 wt% tackifier masterbatch; when EVA exceeds 15 wt%, converters report higher tack but an increased tendency to plate-out on the die lip over extended runs. The downstream process uses a blown film line with a die gap of 1.8–2.2 mm, a blow-up ratio of 2.5:1–3.5:1, and a film thickness of 25–35 µm. Finished product types include silage bale stretch film, agricultural tunnel covers, and temporary greenhouse covers. Published data for LL6802N in multi-season greenhouse exposure is limited; field validation under the intended UV index remains the boundary condition before specification.

When heavy-duty industrial sacks are filled with cold granular product at -20 °C, blend ratio rather than film gauge governs gusset-crease drop impact

On sack lines that fill at low ambient temperatures, converters have observed that increasing total film thickness above 150 µm without adjusting the LDPE modifier content does not raise gusset-crease drop impact proportionally; the failure remains concentrated at the crease where frozen film loses ductility. For non-dangerous granular products, qualification is commonly based on ASTM D1709 dart impact, ASTM D1922 Elmendorf tear, and ASTM D882 tensile yield and break properties, while sacks intended for dangerous goods require testing under the applicable UN performance packaging protocol for the packaging group. No single global material standard governs all heavy-duty sack film structures. The formulation used in these thick gauge structures contains 60–80 wt% LL6802N, 20–40 wt% high-pressure LDPE selected for melt strength, 2–4 wt% carbon black masterbatch when outdoor storage is expected, and 200–500 ppm polymer processing aid to reduce die-lip deposit on long runs. The downstream production process for heavy-duty sacks uses a die gap of 2.0–2.5 mm, a blow-up ratio of 1.8:1–2.2:1, internal bubble cooling, and in-line gusseting; gusset geometry is set after the frost line but before full winder tension to avoid blocking at the crease. Terminal product types include heavy-duty sacks for resin pellets, granular fertilizers, chemical bulk intermediates, and flexible container liners. The operational boundary is that LL6802N fractions above 85 wt% on single-lip air-ring lines reduce bubble stability at low frost line height; melt-strength LDPE or a dual-lip air ring becomes necessary.

In solventless lamination, LL6802N is converted into a blown sealant web of 30–50 µm thickness and is specified primarily by hot-tack and seal-strength response, not by tear yield in the finished laminate. The compliance framework for the sealant web is the same as for direct food contact when the laminate will pack food: FDA 21 CFR 177.1520(c) for the polyethylene layer and Regulation (EU) No 10/2011 migration assessment on the entire multilayer structure. The processing formula for the blown sealant web uses 70–100 wt% LL6802N, 0–30 wt% metallocene LLDPE to lower seal initiation temperature, and 0.5–1.0 wt% anti-block concentrate; anti-block is kept lower than in monolayer packaging because the sealant web is internal and clarity must be retained after lamination. Downstream production uses a die gap of 1.2–1.5 mm, a blow-up ratio of 2.0:1–2.5:1, and corona treatment to 38–42 dyn/cm on the outer surface for adhesive anchorage; sealing performance is verified by ASTM F88 seal strength and ASTM F1921 hot tack on a heat-seal tester under converter-defined dwell and pressure conditions. Terminal product types include stand-up pouches, pre-made bag structures, and flow-wrap packaging. The limiting parameter is corona treatment above 42 dyn/cm: surface oxidation can lower seal strength and narrow the hot-tack plateau.

Air pillow cushioning film: dart impact, seal initiation, and compression creep in inflated void-fill

In inflatable void-fill, the resin is not regulated as food-contact unless the pillows are placed in food delivery packaging; under standard e-commerce use, the primary qualification references ASTM D1709 dart impact, ASTM D1922 Elmendorf tear, and converter-specific compression creep tests after inflation. Formulation for air pillow film is typically 100 phr LL6802N with 200–500 ppm polymer processing aid to reduce melt fracture at high line speed and 0.3–0.8 wt% anti-block to prevent blocking without raising seal initiation excessively. The downstream process begins on a blown film line running 30–80 µm film at a blow-up ratio of 2.0:1–2.8:1; after slitting, the film enters an air pillow machine where seal bars are set between 130 °C and 160 °C, and inflated cells are compressed under a fixed load to detect leaks or creep. Terminal product types include air pillow cushions, bubble mailers, and void-fill bags. Published data for LL6802N in this exact configuration is limited; seal-bar temperature and anti-block level must be validated on the specific pillow machine because residence time during sealing varies among equipment manufacturers.